A system and method for sharing user preferences pertaining to one or more products, without having the user reveal their identity, is described herein. The system is configured for registering a user by receiving a set of biometric samples of the user, processing the set of biometric samples to compute a Secret-Key (S1) corresponding to the user, generating a Unique-Number (N1) using a random number generation algorithm, applying a Function (F1) to the Secret-Key (S1) and the Unique-Number (N1), to compute a Public-Key (P1). Once the user is registered, the system is configured to receive a biometric sample from the user in real-time and compute the Secret-Key (S2) for authenticating the user. Once the user is authenticated, the system may recommend to the user, a candidate product from a product catalog, based on the user's preferences.

The subject matter discussed in the background section should not be assumed to be prior art merely because of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to implementations of the claimed technology.
Traditionally, software applications require people to provide their identity as well as personal information in order to receive personalized services. However, this practice has resulted in several undesirable outcomes. People end up creating a different profile for each application such as Gmail™, Twitter™, Amazon™ etc. As the number of profiles increases, it becomes difficult to manage these profiles. On an average an online user has 7.6 social media accounts. Many of these online profiles are created using fake identities. An estimated 30% of profiles on social media are based on fake identities.
Moreover, in the existing social networking platforms, there is no barrier to keep a user from creating a profile that corresponds to someone other than themselves. Furthermore, users don't always have control over their online profile's visibility to others within or outside of their own human network. User privacy is also at risk as different applications have different privacy standards.
Additionally, software applications often collect more personal information from users than is needed to provide the application's functionality. This information may be misused by these software applications for targeted advertising. Generally, the information captured by these software applications is used to run advertising campaigns targeted at social media audience cohorts whose attributes are extrapolated from their online activity. This may include the web searches they perform, the content they consume, and the social media posts they engage with. This method poses several limitations. The search and social media platforms that track users' activity often have access to users' identity. Although social media platforms mask their users' identity from advertisers and developers, there is a massive burden on the social media platforms to protect their users' identity and keep it hidden from advertisers and developers at all times. More importantly, users' identity is not hidden from the platforms themselves, thereby creating an exception for the platforms in respect of the rule applied to the advertisers that no single entity should have access to people's identity as well as activity.
Furthermore, ecommerce businesses such as Amazon™ and eBay™ capture users' activity data on one product platform and apply it to other products using shared cookies.
Users often have no visibility into which businesses have access to what part of their personal information. The collection of users' attributes and preferences is a one-way flow. Platforms gather users' activity data and retain it permanently. Users have no control over their own activity data once it has been captured by the platform. Moreover, users do not use platforms with the intention of providing the platforms with their personal information. Therefore, finding themselves to be the target of advertisements based on specific personal attributes detected by platforms makes them feel violated. Platforms algorithmically interpret people's engagement data to deduce their attributes and preferences. Hence, there is a level of abstraction between users' actual attributes and preferences, and those targeted by businesses in their advertising campaigns on platforms.
Also, there is an inherent limit to how deeply businesses can understand a user's real attributes and preferences. Users do not know how much of their personal information and preferences that they did not share with anyone intentionally is stored and shared by platforms. This causes widespread anxiety and stress among people. Conversely, in the absence of users' activity on social media platforms, there is insufficient data to extrapolate their attributes and preferences. People's attributes and preferences also change over time. Their activity on various platforms may not reflect all the changes.
Businesses may continue to target users in their advertisements even if they no longer have the attributes they are being targeted for.
Furthermore, users' identities on the internet are stored on a network server. The server requires resources to host users' identities, keep them secure, and perform regular maintenance. Users do not always have control over their digital identity stored on the server. Every identity on the server does not necessarily correspond to a unique person. In the existing art there is no known way to prevent the storage of identities. People need to manage credentials to access their own identities on the servers.
To address some of the above issues and to manage credentials of a multitude of applications, Single Sign-On mechanisms such as OAUTH and SAML are used. The Single Sign-on mechanism allows applications to use tokens and transfer the burden of authentication to federated identity providers such as Google™ and Apple™. During the handoff from a third-party authentication to the client application, typically, personally identifiable information such as name, email, profile photo, etc., is also shared with the client application in an opt-out manner. This reintroduces vulnerabilities in the client application and negates the separation of identity authentication in the first place. Even if no personally identifiable information is handed off to the client application, the third-party authentication system is still susceptible to the same security challenges and all weaknesses are passed on downstream.
Another technique adopted for security is two-factor authentication. There are several ways by which two-factor authentication can be enabled in order to provide an additional layer of security. One method is by sending a code over email or text message.
This assumes that the client application has access to the user's email or phone number which, if true, also means that they have the ability to determine the user's identity with relative ease. Additionally, if the user's phone or email are compromised, this system works in favor of the perpetrator and further injures the victim. Another method of two-factor authentication is enabled by generating a code via a separate authentication application, it assumes that the user has control over that authentication application. If the user loses access to the authenticator application, they lose access to their identity manager. Yet another method of two-factor authentication is enabled by having the user remember a pass-phrase, a visual shape, or answers that they made up for a number of personal questions, or any variant thereof. This usually results in an unreasonable barrier for the user and a bad user experience.
Thus, there is a long-felt need for managing users' profile and preferences without revealing their identity.

System and method for sharing user preferences without having the user reveal their identity


A microfinishing arm assembly for reducing taper on selected bearing journal surfaces of various workpieces rotated about a longitudinal axis. The microfinishing arm assembly includes a primary finishing arm and a taper correction means for applying a plurality of adjacent independently variable grinding pressures. A primary abrasive means for finishing a journal surface is mountable on the primary finishing arm and adapted for use in cooperation with the taper correction means. A measuring means for gauging the bearing journal surfaces at a plurality of spaced points during rotation is utilized with a processor means for receiving the gauging signals, calculating diameters of the journal surfaces and generating a plurality of output signals corresponding to the diameters of the bearing surfaces at spaced points. A comparator means compares the output signals to determine whether a taper exists on selected journal surfaces and controls the extent to which a taper correction means applies variable grinding pressure to the surfaces to correct the taper.

This invention relates to a method and apparatus for correcting diametrical taper formed on workpiece journal surfaces, which were previously ground in a large scale manufacturing grinding machine. Taper, as known in the art, is a condition in which the diameter of a bearing surface is not constant along the axial length of the surface. This condition occurs when grinding machines used to grind the workpieces are improperly maintained or when the various abrading means used to remove material from the workpiece are inadequately dressed during operation.
The prior art contains various examples of grinding processes and machines that utilize an in-process gauging system for altering or inducing modifications in a grinding process to correct taper. As it is known in the art, in-process gauging is a method of controlling a grinding or finishing operation in a machine wherein engagement of the grinding or abrading means with the workpiece is controlled in real-time by a measurement signal generated from a gauge that is likewise in contact with the workpiece surface. The grinding process can then be varied and different results achieved by modifying various controls within the grinding process in relation to the gauging signals.
Prior to this invention, in-process gauging was used to correct taper existing on a plurality of diameters on a workpiece by altering the grinding angle of the grinding wheel in relation to the workpiece during the grinding process. An example of this method is disclosed in U.S. Reissue Pat. No. 28,082 to Price, reissued Jul. 23, 1974. The Price patent discloses a multiple or wide wheel grinding machine with a means provided to vary the relative grinding angle between the surfaces of a workpiece to be ground and the grinding wheel.
In the grinding machine of the Price patent, a pair of electrical size gauges are disposed alongside the workpiece on separate axially spaced bearing surfaces. These size gauges generate electrical signals as the workpiece is being rotated about its longitudinal axis during the grinding cycle. The two signals are compared directly and a third signal is generated when the difference between the signals exceeds a predetermined value. The third signal actuates a means for deflecting the grinding wheel and varying the angle of the grinding contact point in response to the third signal, correcting the taper previously existing on the part while it is in the overall grinding process.
U.S. Pat. No. 3,271,910 to Aisch discloses a method for correcting the size and angular relation between a workpiece to be ground and the grinding wheel. Again, two size gauges are axially spaced f rom each other on two different bearing surfaces of a workpiece such as a automotive crankshaft. The two gauge signals measure the diameters at the extreme ends of the workpiece. When differences are noted in the measured diameters and an independent master diameter, a servo motor is engaged to displace the tail stock, thereby changing the angle that the grinding wheel contacts the workpiece surfaces being ground. This displacement continues until deviations from the master diameter are compensated for (i.e. until there is no longer differences between the diameters measured and the master diameter).
As energy efficiency and fuel consumption considerations become more and more important to automotive manufacturers, bearing journal surfaces on internal combustion engine components and related machine components will continue to be machined to closer and closer tolerances. Increased bearing loads, higher operating speeds and greater durability requirements in today's internal combustion engine manufacturers also further the need for precision finishing of journal bearing surfaces. Included with the requirement for more precision finishing is the need to reduce diametrical taper existing on bearing surfaces. As disclosed in the prior art patents above, taper correction was generally utilized as part of the ongoing grinding process and not as an independent operation used to generate higher quality parts.
Prior art methods utilized a modification in angular relation between the longitudinal axis of the workpiece being ground and the longitudinal axis of the grinding tool or wheel. Taper conditions were measured by taking individual diameter readings from two different bearing surfaces spaced axially apart. As disclosed in the prior art patents, the gauge points were generally spaced apart as far as possible by placing one gauge point on the bearing surface closest to one end of the workpiece and one gauge point on the bearing surface closest to the opposite end of the workpiece.
The relative positioning of these gauges is useful in determining whether there is a difference in diameter between the two surfaces being gauged but fails to measure any of the bearing surface configurations spaced axially between the two gauged surfaces on the workpiece. As is known in the art, there are numerous variables in the grinding process such as grinding means dress intervals, grinding means dress quality and the overall general maintenance of the grinding machine. Thus, utilizing in-process gauging to determine the diameters of the bearing surfaces at two axially spaced positions does not give an accurate indication of the diametrical taper conditions that may exist on bearing surfaces spaced between the two engaging positions.
In process gauging in combination with microfinishing operations is disclosed in U.S. Pat. No. 5,095,663 to Judge et al. The Judge et al patent discloses a microfinishing device using in process gauging to measure the diameter of an internal bearing system during the microfinishing process. The microfinishing process is terminated once a predetermined diameter is achieved on the part. The Judge et al patent discloses the use of size control shoes which monitor the diameter of the journal surface using stationary probes in conjunction with air gauges.
The Judge et al patent further discloses the use of an abrasive backed tape to remove material upon the journal surface upon rotation of the workpiece. A microfinishing shoe is used for pressing the abrasive coated film against a portion of a circumference of a journal surface. The microfinishing shoe disclosed is configured as a one-piece, solid, construction capable of applying only grinding forces transferred from the scissor type action of the grinding arm the shoe is affixed to.

Method and apparatus for correcting diametrical taper on a workpiece


A handheld work apparatus includes a drive motor, an operating-fluid tank and a motor carrier on which the drive motor is held. The operating-fluid tank has a first housing section and a second housing section. The first housing section is realized so as to be integral with the motor carrier. At least a portion of the second housing section is formed from light-transmitting material to permit discerning the fill level of the operating-fluid tank. The motor carrier has a light-transmitting light conductive element for conducting light into the operating-fluid tank.

In the case of handheld work apparatuses having an operating-fluid tank that is realized so as to be integral with the motor carrier and that may contain, for example, lubricating oil for lubricating a component of the work apparatus, or fuel for driving an internal combustion engine, it is desirable that the fill level of the operating-fluid be easily discernible.
Known from US 2008/0087080 A1 is an operating-fluid tank of a handheld work apparatus having a viewing window integrated into a cap part—or having a second housing section—of the operating-fluid tank.
It is also known, for the purpose of discerning the fill level of the operating-fluid tank, to realize the second housing section of the operating-fluid tank entirely from light-transmitting material.
Despite the light-transmitting material of the second housing section comprising the filling opening, the fill level of the operating-fluid tank is only discernible with difficulty.


Apparatus for removing non-condensible gas from a working fluid utilized in a thermodynamic system comprises a membrane having an upstream side operatively connected to the thermodynamic system so that the upstream side of the membrane receives a portion of the working fluid. The first membrane separates the non-condensible gas from the working fluid. A pump operatively associated with the membrane causes the portion of the working fluid to contact the membrane and to be returned to the thermodynamic system.

This invention relates generally to power generation systems in general and more specifically geothermal power generation systems.
Power generation systems or power plants are well-known in the art and are widely used to produce useful work (e.g., electricity) from heat sources. Most such power generation systems generate electricity from heat energy derived from burning fossil fuels (e.g., coal or natural gas) and are referred to herein as thermal power plants. In addition to using heat energy derived from burning fossil fuels, thermal power plants can also be used with a wide variety of other heat sources, such as solar, geothermal, and nuclear sources.
Traditionally, thermal power plants have operated in accordance with the well-known Rankine thermodynamic cycle, although other cycles are known and are being used. In the Rankine cycle, a working fluid, such as water, is heated to produce steam. The steam is then expanded, typically through a turbine, in order to convert into mechanical work the heat energy contained in the working fluid. In the case of an electric power generation system, the turbine is operatively connected to an electrical generator which produces the electricity. While power plants operating in accordance with the Rankine cycle typically use water as the working fluid, other types of working fluids are known and may be better suited to the particular type of heat source utilized and the thermodynamic cycle of the system.
For example, in a geothermal power system, useful work (e.g., electricity) is extracted from heat energy contained in geothermal brine extracted from the earth. While geothermal power generation systems have been constructed that utilize the geothermal brine as the working fluid (i.e., in a xe2x80x9cdirect flashxe2x80x9d type of geothermal system), it is sometimes advantageous to utilize a so-called xe2x80x9cbinaryxe2x80x9d system in which the heat from the geothermal brine is transferred to a recirculating working fluid. The recirculating working fluid is then used to drive the energy conversion device (e.g., the turbine). The use of a separate, recirculating working fluid dispenses with the need to design the turbine to operate with the geothermal brine.
In a binary type geothermal power generation system, a vapor generator system (e.g., a heat exchanger) receives the hot geothermal brine and allows the heat energy contained therein to heat and vaporize the recirculating working fluid. The vaporized working fluid is then expanded through the turbine to produce useful work. The working fluid exhaust stream from the turbine is then condensed, e.g., converted back into a liquid. Thereafter, the condensed working fluid is re-circulated to the vapor generator, whereupon it is re-vaporized and again expanded through the turbine.
While the working fluid for such a binary geothermal power system may comprise water, it is generally preferable to use a working fluid that comprises a volatile organic compound (VOC), such as isobutane or isopentane. Such VOC working fluids are generally better suited for use with the pressure and temperature regimes associated with geothermal power generation systems.
However, regardless of the particular type of working fluid that is utilized, one problem associated with power generation systems in general and geothermal power generation systems in particular, relates to the accumulation of so-called non-condensible gases (NCGs) in the working fluid. Such gases are referred to as xe2x80x9cnon-condensiblexe2x80x9d since they do not condense at the temperatures and pressures at which the working fluid is condensed. That is, the condensation of the working fluid in the condenser system generally does not result in the condensation of the NCGs. In a system utilizing a VOC working fluid, such non-condensible gases typically comprise air and can come from a variety of sources, including the turbine lubricant treatment and recycle system, impurities in the working fluid, air introduced during system repairs, as well as from small leaks which may be present in the system.
While the accumulation of NCGs does not pose a serious problem in the high pressure side of the power generation system (e.g., in the vapor generator and turbine systems) in which is used the working fluid, they can cause problems in the low pressure side of the system, particularly in the condenser. More specifically, the non-condensible gases (NCGs) tend to accumulate at the vapor/liquid interface in the condenser, restricting the movement of the vapor stream to the vapor/liquid interface and lowering the partial pressure of the vapor at the vapor/liquid interface. The result is a decreased heat transfer coefficient in the condenser system and a higher condenser pressure, both of which adversely affect the overall efficiency of the system and result in reduced power output.
Standard practice in binary type geothermal power plants is to allow the NCGs to accumulate until an unacceptable level is reached. The working fluid vapor is vented and the NCGs removed in a batch process. The purified working fluid is then returned to the system. While this practice is effective from a functional standpoint, it is less than ideal in that the efficiency of the power generation system is continuously reduced until such time as the accumulated NCGs are removed from the system. Then, as the NCGs again accumulate, the efficiency of the system is again gradually reduced until the NCGs are again removed or purged from the system. Depending on the specific power generation system, the gradual accumulation and periodic purging of NCGs can reduce annual production by as much as 2 to 4 percent.
Apparatus for removing non-condensible gas from a working fluid utilized in a thermodynamic system may comprise a membrane having an upstream side operatively connected to the thermodynamic system so that the upstream side of the membrane receives a portion of the working fluid. The first membrane separates the non-condensible gas from the working fluid. A pump operatively associated with the membrane causes the portion of the working fluid to contact the membrane.
Also disclosed is a method for removing non-condensible gases from a working fluid utilized in a thermodynamic system that comprises continually separating non-condensible gas from the working fluid during operation of the thermodynamic system. The step of continually separating the non-condensible gas from the working fluid may comprise the steps of contacting with a membrane a portion of the working fluid in a vapor state, the membrane separating the non-condensible gas from the working fluid in the vapor state; and returning to the thermodynamic system the working fluid separated from the non-condensible gas.

Method and apparatus for removing non-condensible gas from a working fluid in a binary power system


The invention contemplates an electrical power meter and method of operating the same, where the meter has electronic components (e.g., a power supply and a voltage sensing circuit) and receives alternating current (AC) voltage from an electrical power line. The inventive meter includes a power supply that converting the AC voltage to a direct current (DC) voltage for powering the electronic components. Also, the AC voltage provides an electrical reference potential for the electronic components. The inventive meter further includes a DC power source (e.g., a diode and/or a resistor in series connection) in a parallel circuit configuration with the AC voltage. The DC power source provides a DC bias voltage to the AC voltage. The AC voltage may create a relatively small voltage across the diode device.

Electric utility companies and power consuming industries have in the past employed a variety of approaches to metering electrical energy. Typically, a metering system monitors power lines through isolation and scaling components to derive polyphase input representations of voltage and current. These basic inputs are then selectively treated to determine the particular type of electrical energy being metered. Because electrical uses can vary significantly, electric utility companies have requirements for meters configured to analyze several different nominal primary voltages, the most common of which are 96, 120, 208, 240, 277 and 480 volts root mean squared (RMS).
Electric utility meters employing electronic components instead of electromechanical components have become more widely used in the industry. The use of electronic components including microprocessor components have made electricity metering faster and more accurate. Of course, the meters typically receive and monitor alternating current (AC) power from the power distribution system. Usually, direct current (DC) power is required to operate the meter's electronic components. Therefore, electronic meters use power supply devices to generate DC power from the already-available and constantly-present AC line voltage. As discussed in U.S. Pat. No. 5,457,621, which is incorporated herein by reference, power supply devices have been created to generate the required microprocessor DC power regardless of the value of the available line voltages (e.g., 96 to 480 volts RMS).
Unlike the former electromechanical components, electronic meters use more sophisticated electronic circuitry to accurately sense and measure AC voltage and current on the power distribution system (i.e., line voltage and line current). In order to minimize cost, however, power sensing circuitry is kept as simple as possible. For example, in lieu of more complicated circuit isolation techniques (although not excluded from scope of the invention), meters often employ power line-referenced voltage sensing techniques.
One type of power line-referenced sensing technique accomplishes voltage sensing with high value resistors in a resistive-divider circuit configuration. Resistive voltage sensing typically requires that the meter's electronic circuits use a voltage that is referenced to one side of the AC power line. In addition, the measurement of electrical power by the electronic metering circuits require that line voltage and line current be sensed very accurately. For example, typical voltage sensing accuracy is usually greater than 0.1% in order to allow the overall meter accuracy to be greater than 0.2%. Line-referenced sensing techniques, like resistive division circuitry, insure compatibility with the sensitive electronic sensing circuits required to meet the meter's rigid measurement accuracy requirements.
Because the voltage being sensed is an alternating voltage signal, the sensed voltage (and therefore also the voltage reference provided to the meter's electronic circuitry) normally swings above and below a referenced ground level. In the context of an electronic circuit that receives DC power from a power supply, for example, often the less expensive electronic circuits (e.g., amplifiers) cannot receive a signal that drops below the power supply's negative power rail (e.g., for a 5 VDC power supply the positive rail may be +5 and the negative rail may be 0 VDC). Therefore, these electronic circuits often cannot use the AC power line's voltage because it swings below the ground-referenced level or negative power rail.
Attempting to use lower cost components and reduce power consumption to keep meter costs down is relevant to any meter environment, and particularly the residential meter environment. For example, although the invention is not limited to this application alone, 240 VAC residential meters often use limited current, fixed voltage capability power supplies (e.g., a linear capacitive divider power supply), which apply even greater power constraints on the power supply.
Therefore, there is a need to adjust or bias the AC voltage inputted to the meter's electronic circuitry so as to prevent it from swinging below the referenced ground level, while maintaining the meter's required level of measurement accuracy.

Bias technique for electric utility meter


A provisioning service datacenter provides a key transfer from a web service datacenter over a first secure channel. In certain versions, the provisioning service datacenter transmits an email having a hashed link to a partner site in response to a key request provided by the partner site. Certain roles at the partner site can respond to the email, thereby returning the hashed link to the provisioning service datacenter. Thereupon, in certain versions, the request is forwarded to a web service datacenter, and a secure channel is provided over which a key can be forwarded to the provisioning service datacenter, and thereupon to the partner site. In certain versions, the key is used to establish a second secure channel.

Security forms an important aspect of network usage. Computer-generated encryption keys represent one security technique. Key distribution involves keys to be used by individuals in addition to keys to be used for companies and web sites to establish their connections to the servers that talk programmatically with the company web sites.
Keys often are distributed directly from a place of operations manually from one IT department to a "partner" site. Certain versions of partner sites are configured to establish secure communications with third-party consumers that allow the consumers to do business with that partner site. One challenge to key usage and acceptance has been key distribution in which keys are distributed to a partner site that to now has been performed largely manually. Such manual distribution includes, for example, manual generation of the key, manual insertion of the data for the key into the datacenter services, and manual transmission of the key to the partner (e.g., by courier or postal service).
This manual distribution of certain keys can result in certain problems. Incorrect keys and/or versions of keys can be sent to the wrong recipients. Delays due to transmissions and errors are frustrating to those parties involved. Additionally, key distribution processes are time-intensive and often require dedicated employees. A compromised key takes considerable time to replace. During this key replacement period, the partner remains susceptible to a large variety of attacks.
Thus, for key usage to become more accepted, improving and automating key distribution would be desirable.


In an OFDM transmission a transmission diversity technique is used without orthogonal signaling. The phases of the subcarriers received at the different antennas are compared by different techniques and then the phases of the signals for different antennas are adjusted for a subsequent transmission over the OFDM interface. The phase (and optionally amplitude) adjustment is calculated in only one (transmitting) side and no orthogonal signaling required. The number of antennas can be increased as much as necessary to get a sharper beam. The negative effects of fading and interference can be reduced so that at same time a down link transmission power can be reduced.

The present invention relates to a transmission diversity device, to a method for a wireless transmission diversity transmission as well as to a computer program for performing such a method.
From EP-0 881 782 A2 a single carrier maximum ratio synthetic transmission diversity device as shown in FIG. 8 is known. According to this known transmission diversity deice antenna elements are arranged at intervals greater than λ/2. A signal received by an antenna element is sent by way of an antenna multiplexer to a receiver, where the signal is demodulated. The thus-demodulated signal is sent to a phase- and power detection section, where a phase and power of the signal are detected. On the basis of the result of such detection, a control section calculated the phase and power of a transmission signal. On the basis of the result of the calculation, a transmission signal generation circuit transmits a transmission signal to each of the antenna elements by way of the antenna multiplexer.
Note that the technique of EP 0 881 782 A2 claiming the calculation of the phase of a signal of each antenna cannot be applied to the multicarrier case, but only to a single carrier case, as it is impossible to measure phases of received signals if there are more than two carriers.
In single carrier applications the phase of the signal changes frequently as the symbols are transmitted serially. Therefore it is difficult to compare phases between different antennas, as the phase is not varying uniformly. Therefore in singles carrier applications a phase comparison is preferably done using pilot symbols which phases are varying uniformly or which are known.
From U.S. Pat. No. 5,973,642 adaptive antenna arrays for orthongonal frequency division multiplexing systems (OFDM systems) with co-channel interference is known. According to this known technique parameters for adaptive antenna arrays in OFDM systems with co-channel interference are estimated. The channel parameter estimation is performed using a two pass process that advantageously expands the temporal scope and considers past, present and future temporal channel estimations during parameter estimation. Channel parameters are estimated by processing he signal through fast FOURIER transforms, temporal filters and inverse fast Fourier transforms. The temporal filters optimize parameters estimation based upon instantaneous correlation of the received signals. This all takes place on the receiver's side of the OFDM system.


An eye protection device for protection against a broad spectrum of incid high intensity radiation includes a beam splitter which transmits the radiation to a first focusing lens which in turn focuses the radiation on a first mirror. The first mirror has a sacrificial surface which desorbs if the radiation has a predetermined minimum intensity. A second lens receives radiation reflected from the first mirror and directs the beam orthogonally onto a second mirror. The beam reflects off the second mirror and is directed back through the second lens which refocuses the beam onto the surface of the first mirror at the original area. When the initial beam was above the minimum, reflectivity at this location will have been destroyed and the beam will pass harmlessly through the mirror. If the initial beam does not destroy the surface, the beam will be reflected back to the beam splitter and then to a receiving device.

1. Field of the Invention
In one aspect this invention relates to eye protection for combat personnel. In yet a further aspect, this invention relates to methods of absorbing light beams.
2. Prior Art
Laser technology has become an increasingly important part of modern technological warfare. Lasers are used in aiming devices, range finders, and as countermeasures to defeat various optical aiming and ranging devices.
As part of the development of laser technology, tuneable dye lasers are being developed which operate by pumping from other lasers or flash lamps. Such lasers provide high energy pulses and can be made in large variety of different wave lengths. The TI-Sapphire lasers now being developed can also provide high repetitions of tuneable energy. This means the exact wave length used by an opponent can not be known in advance requiring that any acceptable protection device be useful over a broad spectrum.
Thus, battlefield personnel are in danger of being exposed to laser radiation of an unknown frequency either casually or intentionally. With the power densities available from today's laser technology, serious damage will be done to unprotected eyes and also the optical devices used on combat vehicles. The radiation comes in discrete bursts of ebergy ranging from a few microjoules up to several joules in intensity and for periods of time from a few nanoseconds to a few microseconds.
To prevent eye damage, any light absorption device must react quickly, on the order of less than 10 picoseconds and absorb light in the range of 400 to 700 nm. Because of the limited time to react, the device must operate passively. A further constraint is the device must transmit light of normal intensity so the user can function in normal light conditions while the bursts of high intensity are prevented from reaching the users eye. This implies that the absorption material operates in a nonlinear manner or initiates protection at some predetermined minimum beam power.
Indirect viewing means which protect a viewer have been developed. One such class of viewers includes a system where the incoming light signal is amplified until all signal are equal in strength and then the modified light beam is attenuated to a safe level. These devices are large and bulky, and also require an external power source making them unsuitable for battlefield application. Particularly with respect to viewers carried by personnel.
Attempts have been made to develop goggles which are suitable for attenuating incoming laser beams during the last several years. The attenuation must be to a power level of about 1 .mu.j which represents an attenuation factor of at least 10,000 since the available lasers can deliver up to several joules of power in the beam with little beam divergence. Partial solutions for beams at a preselected wave length have been achieved; however, there presently exist no protective systems for personnel and equipment which are passive, can react to a broad spectrum of high intensity beams, and simultaneously allow the user to function under normal light conditions.

Laser attenuation device with sacrificial mirror

The United States of America as represented by the Secretary of the Army


The invention comprises a cog type belt having a plurality of transverse teeth on an inner surface. The belt comprises an outer extensible elastomeric layer, an inner compression layer and a tensile member. Each tooth further comprises a non-metallic or plastic transverse member, pillar or rod that extends across the width of each tooth. The opposing outer surfaces of each transverse member are inclined to each other and each end approximately equates to an outer surface of the belt body elastomeric. A compressive load between the sheaves is carried by the rod and the sidewall in proportion to the modulus of each component. The transverse members have pegs or legs that allow proper spatial orientation of each transverse member in each tooth during the fabrication process, thus assuring proper operating characteristics, including proper alignment within a pulley.

This invention relates to belts used in continuously variable transmissions (xe2x80x9cCVTxe2x80x9d), and more particularly to side drive CVT belts comprising cogs or teeth having transverse reinforcement.
It is well known in the art that a gear type transmission may be used for running a motor vehicle, motorcycle or the like. However, gear type transmissions generally have a fixed number of gears. They are usually designed to operate most efficiently in one of the gears, leaving the others to cause the engine to run at less efficient operating points. Consequently, for the purpose of improving efficiency a continuously variable transmission, CVT, is preferable. Various types of belts have been developed for use in continuously variable transmissions.
Generally, the CVT Belts have a silhouette similar to that of a conventional V-belt. In particular, they are broad at the top and narrow at the bottom and designed to fit between the sheaves of a pulley defining an angular groove. The pulley on which the belt is trained comprises a moveable sheave and a fixed sheave, both having a truncated cone shape. Generally, one of the sheaves moves while the other remains fixed.
Moving one sheave in relation to the other varies the effective diameter xcfx86 of the pulley within which the belt operates. Belt speed is a function of the effective diameter of the pulley which is in turn a function of the axial position of the sheaves relative to each other.
CVT type belts in the prior art include belts comprising a plurality of blocks mounted transversely on a tensile member as well as monolithic metal belts and elastomeric belts. Certain forms of cog type belts are also known.
Representative of the art is U.S. Pat. No. 4,493,681 to Takano. Takano discloses a V-section cog belt having rigid metal reinforcing members in each cog extending transversely across the belt. The metal reinforcing members provide transverse rigidity to the belt.
Since the Takano belt operates in contact with the sheaves of the CVT pulley, it is desirable to reduce wear between the belt sides and the pulley as much as possible. This reduces heating, which enhances belt life. Metal rods in direct contact with the sheaves, as taught in Takano, cause undue heating and wear between the belt sides, the reinforcing rods and the pulley sheave surfaces. The use of metal rods also increases the rotating mass and cost of the belt. Further, during fabrication the rods may become misaligned in each tooth. This will cause some of the rods to bear a disproportionately higher load than the adjacent rods. This may result in premature failure. of the overloaded rods and eventually the belt.
Further representative of the art is German patent application DE 197 47 173 A1. It discloses a toothed elastomeric v-belt having transverse teeth. Each tooth having a transverse bore. Each bore may contain tube sections or bar sections. The bore provides a path for cooling air flow through the tooth. However, such bores decrease the compressive strength of each tooth. The application is appropriate for synchronous pulley systems wherein the belt teeth cooperate with conjugate surfaces in a pulley or pulleys.
What is needed is a transverse reinforced CVT belt having a non-metallic or thermoplastic, thermoset or composite transverse reinforcing member in each tooth. What is needed is a transverse reinforced CVT belt having alignment pegs on each transverse reinforcing member. What is needed is a transverse reinforced CVT belt having transverse reinforcing members with sufficient stiffness in the anticipated temperature range. What is needed is a transverse reinforced CVT belt having transverse reinforcing members with a low mass density. The present invention meets these needs.
The primary aspect of the invention is to provide a transverse reinforced CVT belt having a thermoplastic, thermoset or composite transverse reinforcing member in each tooth.
Another aspect of the invention is to provide a transverse reinforced CVT belt having centering pegs on each transverse reinforcing member.
Another aspect of the invention is to provide a transverse reinforced CVT belt having transverse reinforcing members with sufficient stiffness in the anticipated temperature range.
Another aspect of the invention is to provide a transverse reinforced CVT belt having transverse reinforcing members with a low mass density.
Other aspects of the invention will be pointed out or made clear by the following description of the invention and the accompanying drawings.
The invention comprises a cog type belt having a plurality of transverse teeth on an inner surface. The belt comprises an outer extensible elastomeric layer, an inner compression layer and a tensile member. Each tooth further comprises a non-metallic or plastic transverse member, pillar or rod that extends across the width of each tooth. The opposing outer surfaces of each transverse member are inclined to each other and each end approximately equates to an outer surface of the belt body elastomeric. A compressive load between the sheaves is carried by the rod and the sidewall in proportion to the modulus of each component. The transverse members have pegs or legs that allow proper spatial orientation of each transverse member in each tooth during the fabrication process, thus assuring proper operating characteristics, including proper alignment within a pulley.


A stent includes a central portion of helically wound undulations formed of struts, cylindrical end portions, and transition zones between the helical portion and the cylindrical portions. According to a first aspect of the invention, the torsional flexibility of the stent is maximized by having bridges connecting adjacent winding be interrupted by the maximum possible number of undulations. In a preferred design, each winding includes nineteen undulations around the circumference, bridges are provided every five undulations. According to a second aspect of the invention, uniform, opening of the transition zone is achieved by altering the width, and thereby the flexibility, of a series of struts in accordance with their lengths. Specifically, the long transition zone struts are made wider.

1. Field of the Invention
This invention relates broadly to arterial prosthesis. More particularly, this invention relates to vascular stents, and even more particularly to helical stents.
2. State of the Art
Transluminal prostheses are widely used in the medical arts for implantation in blood vessels, biliary ducts, or other similar organs of the living body. These prostheses are commonly known as stents and are used to maintain, open, or dilate tubular structures.
Stents are either balloon expandable or self-expanding. Balloon expandable stents are typically made from a solid tube of stainless steel. Thereafter, a series of cuts are made in the wall of the stent. The stent has a first smaller diameter configuration which permits the stent to be delivered through the human vasculature by being crimped onto a balloon catheter. The stent also has a second, expanded diameter configuration, upon the application, by the balloon catheter, from the interior of the tubular shaped member of a radially, outwardly directed force.
Self-expanding stents act like springs and recover to their expanded or implanted configuration after being compressed. As such, the stent is inserted into a blood vessel in a configuration after being compressed. As such, the stent is inserted into a blood vessel in a compressed state and then released at a site to deploy into an expanded state. One type of self-expanding stent is composed of a plurality of individually resilient and elastic thread elements defining a radially self-expanding helix. This type of stent is known in the art as a "braided stent". Placement of such stents in a body vessel can be achieved by a device which comprises stent". Placement of such stents in a body vessel can be achieved by a device which comprises an outer catheter for holding the stent at its distal end, and an inner piston which pushes the stent forward once it is in position. However, braided stents have many disadvantages. They typically do not have the necessary radial strength to effectively hold open a diseased vessel. In addition, the plurality of wires or fibers used to make such stents could become dangerous if separated from the body of the stent, where it could pierce through the vessel.
Therefore, recently, self-expanding stents cut from a tube of superelastic metal alloy have been manufactured. These stents are crush recoverable and have relatively high radial strength. U.S. Pat. No. 5,913,897 to Corso, U.S. Pat. No. 6,042,597 to Kveen, and WPO Patent Application WO 01189421-A2 (with inventors Cottone and Becker, and referred to herein as "Cottone") each teach superelastic cut-tubular stents having a helically wound configuration of repeating undulations. Bridge structures connect adjacent circumferential windings by extending between loop portions of undulations on adjacent windings. However, the bridge structures and arrangements do not maximize the torsional flexibility of the stents. In particular, Cottone describes a stent having a helical pattern of bridges (connections) connecting windings of the helix which is reverse in handedness from the undulations of the windings which form the central portion of the stent. The design described provides the stent with asymmetric characteristics that cause the stent to resist torsional deformations differently in one direction versus the other. In addition, each "helix of connections" forms a string of connections in which the connections are interrupted by only one and one-half undulations. As such, that string is resistant to stretching and compression. Accordingly, when a stent so designed is twisted torsionally, that string of connections causes constriction of the stent when twisted in the "tightening" direction (i.e., in the direction of the windings) and expansion of the stent when twisted in the opposite "loosening" direction. This differential torsional reaction results in the undulations of the stent being forced out of the cylindrical plane of the surface of the stent, such that the stent appears to buckle when twisted in the "loosening" direction.
In fact, even if the stent were constructed opposite to Cottone's preferred embodiment (that is, with a helix of bridges having the same handedness as the helix of undulations), the same effect results. Stents built with constructions containing a string of bridges separated by only a small number of undulations behave poorly when twisted. That is, they react differently if the stent is twisted one way versus the other, and the surface of the stent tends to buckle when twisted only slightly in the "loosening" direction.
Moreover, due to the helical windings of the stents, the stents described by Corso and Kveen terminate unevenly at the end of the helical windings. As such, the terminus of the final winding fails to provide a uniform radial expansion force 360° therearound. Cottone addresses this problem by providing a stent constructed with a helically wound portion of undulations in the central portion of the stent, a cylindrical portion of undulations at each end of the stent, and a transition zone of undulations joining each cylindrical portion to the central helically wound portion. The undulations of the transition zone include struts which progressively change in length.
Because the transition zone must mate directly to the cylindrical portion on one side and to a helically wound portion on the other side, the transition zone must create a free end from which the helical portion extends, must contain a bifurcation, and must depart from a uniform strut length for the struts around the circumference of the transition zone so that the transition from the helically wound portion to the cylindrical portion can occur.
However, if there are longer struts in a portion of the transition zone, that portion tends to expand more than the portion with shorter struts because the bending moments created by longer struts are greater than those created by shorter struts. Also, for the same opening angle between two such struts when the stent is in an expanded state, the opening distance between such struts is greater if the struts are longer. These two factors combine their effects in the portion of the transition zone with longer struts so that the apparent opening distances are much larger than in the portion where the struts are shorter. As such, the simple transition zone described by Cottone is not amenable to uniform expansion and compression, which is a requirement of an efficient self-expanding stent.
Moreover, except in the case of the Cottone helical stent which is provided with a transition zone, and except where there are different strut lengths in the undulations at the ends of a stent, stents generally contain struts of one length throughout their design. Accordingly, in order to achieve uniform opening of the stent, all the struts have substantially the same width as well as length.

This patent is subject to a terminal disclaimer.

Helical stent having improved flexibility and expandability


In a defect inspection device that irradiates a surface of a sample or a surface of a pattern chip with an illumination light shaped to extend in a first direction, and detects a scattered light generated from the surface of the sample or the surface of the pattern chip by the illumination light to detect a defect on the surface of the sample, the pattern chip has a dot pattern area in which multiple dots are arrayed in multiple rows and multiple columns, a minimum interval between the dots corresponding to the lines aligned in the first direction among the multiple dots arrayed in the dot pattern area in a second direction orthogonal to the first direction is smaller than a width of the illumination light, and a minimum interval between the multiple dots arrayed in the dot pattern area is larger than a resolution of the detection optical system.

For example, a semiconductor device, a liquid crystal display element, and a printed circuit; board are manufactured by forming a pattern on a substrate. In a manufacturing process for the semiconductor device, the liquid crystal display element, and the printed circuit board, in order to inspect a defect occurring at the time of forming the pattern and take countermeasures against the defect, a defect inspection device that detects a defect occurrence condition is used.
The defect inspection device of this type is disclosed in Patent Literature 1. Patent Literature discloses "a defect inspection device for inspecting a sample, including a table unit, an illumination light irradiation unit, a detection optical system unit, and a signal processing unit in which the table unit is movable and allows a sample to be inspected and a pattern chip to be placed on the table unit, the illumination light irradiation unit irradiates a surface of the sample placed on the table unit or a surface of the pattern chip with an irradiation light linearly formed, the detection optical system unit includes a plurality of detection optical systems each having an objective lens and an image sensor and placed at a plurality of locations above the table unit, and forms on the image sensors and detects images caused by scattered lights incident to the respective objective lenses of the plurality of detection optical systems placed at the plurality of locations, among scattered lights generated from the sample irradiated with the linearly formed illumination light by the illumination light irradiation unit, and the signal processing unit processes signals detected by the plurality of detection optical systems of the detection optical system unit to detect a defect of the simple surface, wherein a plurality of repetitive patterns for generating the scattered lights corresponding to positions of the respective objective lenses of the multiple detection optical systems in the detection optical system unit when the linearly formed illumination light is irradiated by the illumination light irradiation unit is periodically formed in the pattern chip"(claim 1 of scope of claims).

Defect inspection device, pattern chip, and defect inspection method


A spark plug is provided with: a central electrode; a ground electrode forming a spark discharge gap with the center electrode; and a chip welded to at least one of the electrodes. The chip has a thermal expansion coefficient smaller than a thermal expansion coefficient of the electrode to which the chip is welded, and the difference between the content A (mass %) of a noble metal component in the chip and the content B (mass %) of a noble metal component in the electrode (A−B) is 50 mass % or more. In an intermediate layer between the chip and the electrode, holes are present. When the length of a boundary between the chip and the intermediate layer is L (mm), and the length of the holes in a direction along the boundary of the chip and the intermediate layer is N (mm), 0.1≦N/L≦0.4.

The electrodes to which the chips are welded are formed of a metal with nickel as a main component, for example. Generally, the thermal expansion coefficient of the chips is smaller than the thermal expansion coefficient of the electrodes to which the chips are welded. Thus, at high temperature, the difference in thermal stress between the chips and the electrodes becomes relatively large. As a result, oxide scales are rapidly formed between the chips and the electrodes as a thermal cycle is repeated, possibly resulting in the peeling (detachment) of the chips from the electrodes in an early period.
In order to prevent the peeling (detachment) of the chip, the chip may be welded to the electrode very strongly so that the formation of oxide scales between the chip and the electrode can be suppressed. However, in this case, a part of the chip on the electrode side is pulled by thermal expansion of the electrode and is thus thermally expanded (deformed) more. Thus, the difference in thermal expansion between the part of the chip on the electrode side and a part of the chip on the opposite side from the electrode is increased. As a result, the part of the chip on the opposite side from the electrode may be deformed (such as warped), or breakage may be caused in the part.
The present invention is made in view of the above problems, and a purpose of the present invention is to improve the weldability of a chip to an electrode in a spark plug in which the thermal expansion coefficient of the chip is smaller than the thermal expansion coefficient of the electrode to which the chip is welded, so that deformation or breakage of the chip can be effectively prevented while peeling (detachment) of the chip from the electrode can be more reliably prevented.


A towable Otter Board having upstream facing flap portions is disclosed for use in trawl fishing applications. The flap portions are used to divert fluid flow from the concave lower board surface to the upper convex board surface which serves to shift a vortex formed proximate the upper board surface further downstream to a position closer to the trailing edge of the board which provides considerable improvement over the prior art by decreasing drag and increasing lift. A single wing and bi-plane version of the board is disclosed.

In general, the otter board used in trawl fishing having as large as possible value of L/D, i.e. having a large net-mouth expanding force (L) and/or a small drag (D) is desirable. When these requisites are satisfied, the drag of otter board is decreased, which enables tugging of large trawl net and using of the otter board having smaller surface area with easier handling and lower costs.
In developing the heretofore known otter boards, a number of attempts have been carried out for making the value L/D as large as possible.
For example, a slit type of otter board is suggested which has a plurality of longitudinal slits 2, 2 . . . in the concave inner surface thereof as shown in FIG. 5, or a multi-wing type of otter board is proposed which comprises several wings 4, 4 . . . having each a large ratio of longitudinal and lateral sizes.
The first type of otter board having slits 2 therein has an substantially decreased surface area thereof, so that the drag D thereof is decreased but its net-mouth expanding force (L) is also decreased, while the second multi-wing type of otter board has an increased net-mouth expanding force (L) but its drag (D) is also increased.


A dielectric layer for capacitive element is formed on a lower electrode. An interlayer insulating layer is formed on the lower electrode and the dielectric layer for capacitive element. A plug hole reaching the dielectric layer for capacitive element is formed in the interlayer insulating layer. Upper electrodes are formed to fill in the plug hole and positioned opposite to the lower electrode with the dielectric layer for capacitive element interposed. The dielectric layer for capacitive element is in contact with the upper surface of the lower electrode at a region directly below the plug hole and a region outside the sidewall of the plug hole. Thus, a semiconductor device having a capacitive element with a greater capacitance which prevents diffusion of metal atoms from the lower electrode as well as a manufacturing method thereof are provided.

1. Field of the Invention
The present invention relates to semiconductor devices having capacitive elements and manufacturing methods thereof. More particularly, the present invention relates to a semiconductor device having a plurality of metal interconnection layers on a semiconductor substrate and having a capacitive element in an opening of an insulating layer between upper and lower metal interconnection layers as well as a manufacturing method thereof.
2. Description of the Background Art
FIG. 16 is a cross sectional view schematically showing a structure of a conventional semiconductor device having a capacitive element. A capacitive element C has a lower electrode 109, a dielectric layer for capacitive element 110, and an upper electrode 112. Lower electrode 109 is formed on a surface of a semiconductor substrate 101, which is isolated by a trench isolation 102 and formed when a gate electrode 105 of a transistor T is formed. Lower electrode 109 has a stack of a polysilicon layer 109a doped with impurities and a high melting point metal film 109b of, for example, W (tungsten), Ti (titanium), Co (cobalt), Ni (nickel) or Mo (molybdenum), or a silicide 109b thereof. Upper electrode 112 is formed on lower electrode 109 with dielectric layer for capacitive element 110 interposed. Upper electrode 112 is a polysilicon or amorphous silicon doped with impurities such as P (phosphorus) or As (arsenic), or a compound of a high melting point metal film such as TiN (titanium nitride). Dielectric layer for capacitive element 110 is, for example, a high dielectric film such as a silicon oxide film, silicon nitride film or tantalum oxide film formed by CVD (Chemical Vapor Deposition).
An interlayer insulating layer 107 is formed to cover capacitive element C. Each of lower electrode 109 and upper electrode 112 is electrically connected to a metal interconnection 113 through a metal plug 108 filling in a contact hole 107a. Metal interconnection 113 applies a potential to each of lower electrode 109 and upper electrode 112, so that electric charges are accumulated between the electrodes.
Note that transistor T has a pair of source/drain regions 103, a gate insulating layer 104, and a gate electrode layer 105. The pair of source/drain regions 103 are separated on the surface of semiconductor substrate 101. Gate electrode layer 105 is formed on the region between the pair of source/drain regions 103 through gate insulating layer 104. An insulating layer 106 is formed on gate electrode layer 105. Each of the pair of source/drain regions 103 is electrically connected to metal interconnection 113 through metal plug 108 in contact hole 107a.
In the semiconductor device having a conventional capacitive element, the surface of interlayer insulating layer 107 covering capacitive element C and transistor T is planarized by CMP (Chemical Mechanical Polishing). The planarization is performed to reduce steps at the surface of interlayer insulating layer 107, so as to facilitate pattern formation at the upper layer by photolithography for greater dimensional accuracy.
When the planarization is performed by CMP, however, the upper surface of interlayer insulating layer 107 is planarized almost completely, whereby a thickness h1 of films on gate electrode 105 becomes smaller than a thickness h3 of a film on source/drain region 103 by a thickness of gate electrode 105. Likewise, a thickness h2 of a film on upper electrode 112 becomes smaller than thickness h1 of films on gate electrode 105 by the thicknesses of dielectric layer for capacitive element 110 and upper electrode 112.
Usually, there is a variation in thickness of films removed at the time of planarization by CMP. Thus, thickness h2 must be sufficiently large to prevent exposure of upper electrode 112 from interlayer insulating layer 107 during planarization. However, as thickness h2 increases, thickness h3 of the film on source/drain region 107 inevitably increases. The increase in thickness h3 results in greater aspect ratio of contact hole 107a (a ratio of depth to diameter of contact hole 107a) reaching source/drain region 103. As a result, it becomes difficult to stably form, by dry etching, contact hole 107a with sufficient dimensional accuracy. In some cases, the etching stops en route, preventing proper formation of contact hole 107a.
A technique for solving the aforementioned problem is disclosed in Japanese Patent Laying-Open No. 11-274428. FIG. 17 is a cross-sectional view schematically showing a structure of a semiconductor device having a capacitive element disclosed in the aforementioned laid-open application No. 11-274428. Referring to FIG. 17, capacitive element C has a lower electrode 209, a dielectric layer for capacitive element 210, and an upper electrode 212A. Lower electrode 209 is formed on a silicon oxide film 207 [209] on a silicon substrate 201, having a polysilicon film 209a and a titanium silicide film 209b. Upper electrode 212A is formed to fill in a hole 211a opened in an interlayer insulating layer 211. Upper electrode 212A is electrically connected to an aluminum interconnection 213A deposited on interlayer insulating layer 211.
Now, a method of manufacturing the semiconductor device having the capacitive element will be described.
FIGS. 18 to 23 are schematic cross sectional views sequentially showing the method of manufacturing the semiconductor device having the capacitive element shown in FIG. 17. Referring to FIG. 18, after silicon oxide film 207 is formed on silicon substrate 201, a lower electrode 209 having polysilicon film 209a and titanium silicide film 209b is formed.
Referring to FIG. 19, interlayer insulating layer 211 is formed to cover lower electrode 209. An opening 211a reaching lower electrode 209a is opened in interlayer insulating layer 211. A silicon nitride film 210, later to be a dielectric layer for capacitive element, is formed over the entire surface to cover the inner surface of opening 211a.
Referring to FIG. 20, a contact hole 211b reaching lower electrode 209 is formed in interlayer insulating layer 211 and silicon nitride film 210.
Referring to FIG. 21, a tungsten film 212 is formed over the entire surface to fill in hole 211a and contact hole 211b. Thereafter, tungsten film 212 is polished by CMP.
Referring to FIG. 22, the upper surface of silicon nitride film 210 is exposed by CMP, so that upper electrode 211A and a plug conductive layer 212B of tungsten are formed.
Referring to FIG. 23, any unwanted portion of silicon nitride film 210, exposed from the surface, is removed by dry etching.
Thereafter, the aluminum interconnection layer is formed to complete a semiconductor device having capacitive element C as shown in FIG. 17.
In the structure shown in FIG. 17, upper electrode 212A for capacitive element C is formed as a plug layer filling in hole 211A. Thus, upper electrode 212A can be electrically connected to aluminum interconnection layer 213B directly at the upper surface of interlayer insulating layer 211. This eliminates the need for a contact hole connecting upper electrode 212A and aluminum interconnection 213B, so that the thickness of interlayer insulating layer 211 is restrained. Thus, the problem as described in conjunction with the structure of FIG. 16, associated with greater thickness h3 of the film on source/drain region 103, can be alleviated.
However, the structure shown in FIG. 17 still suffers from problems associated with a complicated manufacturing process or insufficient capacity of the capacitive element when diffusion of metal atoms from a lower electrode is considered. In the following, the problems will be described in detail.
(1) Increased number of manufacturing steps
In the structure shown in FIG. 17, for example, if copper (Cu) is used for lower electrode 209, the copper atoms easily diffuse into an insulating layer such as a silicon oxide film, causing a change of threshold voltage of the transistor or the like. Thus, lower electrode 209 is covered with a barrier layer to prevent diffusion of the copper atoms from lower electrode 209.
In the structure of FIG. 17, additional barrier layer is required for that purpose, involving additional manufacturing steps.
Alternatively, dielectric layer for capacitive element 210 can be provided with a function of preventing diffusion of copper atoms. However, in the structure of FIG. 17, dielectric layer for capacitive element 210 is formed only in hole 211a, so that the diffusion of copper atoms from lower electrode 209 cannot be reliably prevented.
(2) Capacitance of capacitive element C
In the structure of FIG. 17, lower electrode 209 and upper electrode 212A, that are opposite to each other, are flat in shape. Therefore, the capacitive element cannot ensure a sufficient capacitance.
An object of the present invention is to provide a semiconductor device having a capacitive element capable of preventing diffusion of metal atoms from a lower electrode with a streamlined manufacturing process as well as a manufacturing method thereof.
Another object of the present invention is to provide a semiconductor device having a capacitive element allowing proper formation of a contact hole and providing increased capacitance as well as a manufacturing method thereof.
A semiconductor device having a capacitive element according to one aspect of the present invention is provided with a lower electrode layer, a dielectric layer for capacitive element, an insulating layer, and an upper electrode layer. The dielectric layer for capacitive element is formed on the lower electrode layer. The insulating layer is formed on the lower electrode layer and the dielectric layer for capacitive element and has a hole reaching the dielectric layer for capacitive element. The upper electrode layer fills in the hole and is disposed opposite to the lower electrode layer with the dielectric layer for capacitive element interposed. The dielectric layer for capacitive element is in contact with an upper surface of the lower electrode layer at a region outside the region directly below the hole and the sidewall of the hole.
In the semiconductor device having the capacitive element according to one aspect of the present invention, the dielectric layer for capacitive element is in contact with the lower electrode layer not only at the region directly below the hole but also at the region outside the sidewall of the hole, so that the semiconductor device produces greater effect of preventing diffusion of metal atoms from the lower electrode layer as compared with the conventional structure (FIG. 17).
Additional diffusion barrier layer is not necessary since the dielectric layer for capacitive element also acts as such a diffusion barrier layer. Thus, additional step of forming the diffusion barrier layer is unnecessary, whereby a diffusion barrier layer with sufficient diffusion preventing effect can be provided by a streamlined manufacturing process.
The upper electrode layer is formed as a plug layer to fill in the hole opened in the insulating layer. Accordingly, the upper electrode layer is electrically connected to a portion which is later to be an interconnection, directly at the upper surface of the insulating layer. Thus, a contact hole needs not be opened to connect the upper electrode layer and interconnection portion, whereby the thickness of the insulating layer can be restrained. As a result, the problem associated with increased thickness of the insulating layer on the source/drain region of the conventional example can be alleviated.
In the semiconductor device having the capacitive element according to one aspect of the present invention, preferably, the dielectric layer for capacitive element is in contact with the side surface of the lower electrode layer.
This prevents diffusion of metal atoms from the lower electrode layer.
In the semiconductor device having the capacitive element according to one aspect of the present invention, preferably, the dielectric layer for capacitive element has a sidewall constituting a surface that is substantially continuous to the sidewall of lower electrode layer.
This enables patterning of the lower electrode layer and the dielectric layer for capacitive element with use of the same mask. Thus, as compared with the case where different masks are used for patterning the dielectric layer for capacitive element and the lower electrode layer, less masks are used.
A semiconductor device having a capacitive element according to another aspect of the present invention is provided with a first lower electrode portion, an insulating layer, a second lower electrode portion, a dielectric layer for capacitive element, and an upper electrode layer. The insulating layer is formed on the first lower electrode portion and has a hole reaching the first lower electrode portion. The second lower electrode portion has a cylindrical portion formed along the side surface of the hole and is electrically connected to the first lower electrode portion. The dielectric layer for capacitive element is formed on the second lower electrode portion. The upper electrode portion fills in the hole and is opposite to the second lower electrode portion through the dielectric layer for capacitive element.
In the semiconductor device having the capacitive element according to another aspect of the present invention, the second lower electrode portion is formed along the side surface of the hole, having a cylindrical portion. This contributes to an increase in area where the lower and upper electrode portions are opposite to each other, whereby the capacitive element may have increased capacitance.
The upper electrode layer is formed as a plug layer which fills in the hole opened in the insulating layer. Thus, the upper electrode layer can be electrically connected to a portion to be an interconnection directly at the upper surface of the insulating layer. Thus, a contact hole for connecting the upper electrode layer and the interconnection portion needs not to be provided, whereby the thickness of the insulating layer can be restrained. Consequently, the problem associated with increased thickness of the insulating layer on the source/drain region of the conventional example can be alleviated.
In the semiconductor device having the capacitive element according to another aspect, preferably, the second lower electrode portion is not positioned on the upper surface of the insulating layer.
Thus, the second lower electrode portion can be patterned as separate from the dielectric layer for capacitive element or the like.
In the semiconductor device having the capacitive element according to another aspect, preferably, the second lower electrode portion has a portion extending on the upper surface of the insulating layer.
This enables the second lower electrode portion and the dielectric layer for capacitive element and the like to be patterned by the same mask.
In the semiconductor device having the capacitive element according to another aspect, preferably, the hole is formed to have a diameter greater than the area of the first lower electrode portion when viewed from above.
The hole filled with the upper electrode layer has a greater diameter, so that the capacitance of the capacitive element can be increased.
In the semiconductor device having the capacitive element according to another aspect, preferably, a plurality of holes are formed, each reaching the first lower electrode portion. The second lower electrode portion has a portion extending along a circumferential surface of each of the plurality of holes, and the upper electrode layer is formed to fill in each of the plurality of holes.
The capacitive element can be provided with increased capacitance by convex and concave portions formed by the plurality of holes.
A method of manufacturing a semiconductor device having a capacitive element according to one aspect of the present invention is provided with steps of: forming a dielectric layer for capacitive element on a lower electrode layer; forming an insulating layer to cover the lower electrode layer and the dielectric layer for capacitive element; forming a hole in the insulating layer reaching the dielectric layer for capacitive element; and forming an upper electrode layer to fill in the hole.
In the method of manufacturing the semiconductor device having the capacitive element according to one aspect of the present invention, a hole is formed after the lower electrode layer is covered with the dielectric layer for capacitive element. Thus, the dielectric layer for capacitive element is in contact with the lower electrode not only at a region directly below the hole but also at a region outside the hole. Thus, as compared with the conventional structure (FIG. 17), the semiconductor device is provided with enhanced effect of preventing diffusion of metal atoms from the lower electrode.
The dielectric layer for capacitive element also acts as a diffusion barrier layer, so that no additional diffusion barrier layer is necessary. Thus, additional step of forming the diffusion barrier layer is unnecessary, whereby a diffusion barrier layer with enhanced diffusion preventing effect can be obtained by a streamlined manufacturing process.
The upper electrode layer is formed as a plug layer which fills in the hole opened in the insulating layer. Thus, the upper electrode layer can be electrically connected to a portion, later to be an interconnection, directly at the upper surface of the insulating layer. As a result, a contact hole for connecting the upper electrode layer and the interconnection portion needs not be formed, whereby the thickness of the insulating layer can be restrained. Consequently, the problem of the conventional example associated with increased thickness of the insulating layer on the source/drain region can be alleviated.
In the method of manufacturing the semiconductor device having a capacitive element according to one aspect, preferably, the step of forming the dielectric layer for capacitive element on the lower electrode layer has a step of forming the dielectric layer for capacitive element to cover the upper and side surfaces of the lower electrode layer after patterning the lower electrode layer.
Thus, diffusion of metal atoms from the side surface of the lower electrode layer can be prevented.
In the method of manufacturing the semiconductor device having the capacitive element according to one aspect, preferably, the step of forming the dielectric layer for capacitive element on the lower electrode layer has a step of patterning a conductive layer and the dielectric layer for capacitive element after forming the dielectric layer for capacitive element on the conductive layer later to be a lower electrode layer.
This enables patterning of the lower electrode layer and the dielectric layer for capacitive element with use of the same mask. Thus, as compared with case where the dielectric layer for capacitive element and the lower electrode layer are patterned with use of different masks, the process can be simplified.
A method of manufacturing a semiconductor device having a capacitive element according to another aspect of the present invention is provided with steps of: forming a first lower electrode portion; forming an insulating layer on the first lower electrode portion; forming a hole reaching the first lower electrode portion in the insulating layer; forming a second lower electrode portion having a portion along the side wall of the hole and electrically connected to the first lower electrode portion; forming a dielectric layer for capacitive element on the second lower electrode portion; and forming an upper electrode layer which fills in the hole and is opposite to the second lower electrode portion with the dielectric layer for capacitive element interposed.
In the method of manufacturing the semiconductor device having the capacitive element according to another aspect of the present invention, the second lower electrode portion is formed along the sidewall of the hole, hence having a cylindrical portion. This increases an area where the lower and upper electrodes are opposite to each other, so that the capacitive element may have increased capacitance.
The upper electrode layer is formed as a plug layer which fills in the hole opened in the insulating layer. Thus, the upper electrode layer can be electrically connected to a portion, later to be an interconnection, directly at the upper surface of the insulating layer. As a result, a contact hole for connecting the upper electrode layer and the interconnection portion needs not be formed, whereby the thickness of the insulating layer can be restrained. Consequently, the problem of the conventional example associated with increased thickness of the insulating layer on the source/drain region can be alleviated.
In the method of manufacturing the semiconductor device having the capacitive element according to another aspect, preferably, the step of forming the second lower electrode portion has a step of forming a conductive layer, which is later to be a second lower electrode portion, to cover the inner surface of the hole and the upper surface of the insulating layer and then patterning the conductive layer to leave it only in the hole.
This enables the second lower electrode portion to be patterned as separate from the dielectric layer for capacitive element or the like.
In the method of manufacturing the semiconductor device having the capacitive element according to another aspect, preferably, the step of forming the second lower electrode portion has a step of forming a conductive layer, which is later to be a second lower electrode portion, to cover the inner surface of the hole and the upper surface of the insulating layer and then patterning the conductive layer along with the dielectric layer for capacitive element formed on the conductive layer later to be the second lower electrode portion to leave them in the hole and at a part of the upper portion of the insulating layer.
This enables the second lower electrode portion, the dielectric layer for capacitive element and the like to be patterned by the same mask.
In the method of manufacturing the semiconductor device having the capacitive element according to another aspect, preferably, the hole is formed to have a diameter greater than the area of the upper surface of the first lower electrode portion when viewed from above.
The diameter of the hole filled with the upper electrode layer is increased, so that the capacitive element may have increased capacitance.
In the method of manufacturing the semiconductor device having the capacitive element according to another aspect, preferably, a plurality of holes are formed, each of which reaching the first lower electrode portion. The second lower electrode portion has a portion extending along the sidewall of the plurality of holes, and the upper electrode portion is formed to fill in each of the plurality of hole.
The convex and concave portions formed by the plurality of holes may provide a capacitive element with greater capacitance.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

Manufacturing method of semiconductor device having capacitive element

Ryoden Semiconductor System Engineering Corporation


There is provided a disk drive cover. The disk drive cover includes a bottom layer including a metallic bottom layer body and a first flap formed in the bottom layer body. The first flap defines an exposed inner body edge of the bottom layer body. The disk drive cover further includes a damping layer. The disk drive cover further includes a top layer including a metallic top layer body and a second flap. The second flap is formed in the top layer body with the second flap extending into the bottom layer adjacent the first flap. The second flap defines an exposed second flap edge. The second flap edge is disposed in mechanical communication with the exposed inner body edge for electrically grounding the top and bottom layers.

1. Field of the Invention
The present invention relates generally to disk drives, and in particular to a disk drive cover with top and bottom layers electrically grounded with first and second flaps, and a method of manufacturing the same.
2. Description of the Prior Art
The typical hard disk drive includes a head disk assembly (HDA) and a printed circuit board assembly (PCBA) attached to a disk drive base of the HDA. The head disk assembly includes the disk drive base, a cover, at least one magnetic disk, a spindle motor for rotating the disk, and a head stack assembly (HSA) that includes a transducer head supported by a slider for reading and writing data from and to the disk.
The spindle motor includes a spindle motor hub that is rotatably attached to the disk drive base and supports at least one disk. The head stack assembly includes an actuator assembly including the sliders and a flex circuit cable assembly attached to the actuator assembly. The actuator assembly includes an actuator that is rotatably coupled to the disk drive base and is used to read and write data from and to the disk. A plurality of fasteners, such as metal screws, are disposed about a periphery of the disk drive cover and engage the periphery of the disk drive base for attachment of the disk drive cover with the disk drive base. In addition, as support for the actuator, a fastener is engaged to a pivot bearing cartridge through the disk drive cover. Another fastener is used to support the spindle motor and is engaged to the spindle motor also through the disk drive cover.
A topic of concern is mitigating the effects of various vibrations within the disk drive due to the many dynamic components. In this regard, disk drive cover designs have included a layered configuration with an intermediate layer being formed of a damping material disposed between rigid metal layers. As a result the various layers may become electrically insulated from each other. Various configurations have been implemented to electrically ground such rigid metal layers so as to mitigate against any undesirable static discharge events. Grounding configurations have included use of metal fasteners (such as screws) through the various layers to provide electrical grounding of such layers to the disk drive base and other disk drive components (e.g., a pivot bearing cartridge or a spindle motor shaft). However, the lowermost layer may be coated with an electrically insulative coating (such as e-coat) for cleanliness purposes within the disk drive. This would make grounding of such lowermost layer difficult. Other electrical grounding configurations have included selectively exposing the metal layers to each other by not including a portion of damping material at such locations. However, this would preclude utilization of prefabricated solid sheets of laminated metal and damping material that may be readily stamped to form disk drive cover units. Accordingly, there is a need for an improved disk drive cover configuration in comparison to the prior art.

Disk drive cover with top and bottom layers electrically grounded with first and second flaps and method of manufacturing the same


A tubular fastener element (34) is inserted into an opening(44) in a wall (W) until a flange (40) at the trailing end of the fastener element (34) is in contact with the wall (W). Then, an externally threaded end (32) of a rod (28) is inserted into a center opening (56) in the fastener element (34) from the flange side (42) of the wall (W) and is mated with internal threads (52) in the fastener element (34) beyond the second side (50) of the wall (W). A tubular mandrel (24) that surrounds the rod (28) is moved into contact with the entrance portion of the center opening (56) in the tubular fastener (34). The outside diameter of the mandrel (24) is larger than the inside diameter (58) of the center opening (56) in the fastener element (34). The rod (28) is retracted to cause a reduced thickness wall portion (46) of the fastener element (34) to collapse and form a second radial flange (60) on the second side (50) of the wall (W). The mandrel (24) is forced axially into the center opening (56) in the fastener element (34). This causes a tubular end portion (36) of the fastener element (34) that is in the opening (44) in the wall (W) to radially expand into tight engagement with the sidewall of the wall opening (44). It also cold expands the wall material surrounding the opening (44) for fatigue enhancement of the wall material.

This invention relates to a method and apparatus for connecting an internally threaded fastener element to a wall by cold expanding a non-threaded tubular portion of the fastener element within an opening in the wall and providing the fastener element with wall contacting flanges on both sides of the wall.
The aerospace industry utilizes a fastener that is in the nature of a tubular rivet with internal threads. It can be installed in seconds into an opening in a wall from one side of the wall. No finishing work is required once the fastener is installed. It is ready for use with clean threads available for screw attachment. This tubular rivet has a flange on one end. The opposite end is inserted into the opening in the wall and the tubular rivet is pushed into the opening until the flange is against the wall. A rod with a threaded end is then inserted into the tubular rivet from the flange side of the wall and is connected to threads inside the tubular rivet. Then, a hand or power tool is operated to pull on the rod. This causes a wall portion of the tubular rivet on the second side of the wall to bulge out radially and form a second flange that is moved into tight engagement with the second side of the wall. A tubular rivet system of this type is currently provided by RIVNUT(copyright) Engineered Products, Inc. of Kendallville, Ind. An early form of this type of system is disclosed by U.S. Pat. No. 2,384,347, granted Sep. 4, 1945, to Michael Schultz. A problem with known tubular rivets is that they often rotate in the opening when torque is applied to a screw that is connected to the tubular rivet after it has been installed.
It is known to install a nut holder on a wall at the location of an opening in the wall and then connect a nut to the installed nut holder. A tubular stem portion of the nut holder is inserted into the opening in the wall and is then radially expanded to connect it to the wall and also cold work the wall material surrounding the opening for fatigue life enhancement. Then the nut is connected to the nut holder to provide bolt receiving threads. Examples of this type of system are disclosed by U.S. Pat. No. 5,096,349, granted Mar. 17, 1992, to Michael A. Landy, Roger T. Bolstad, Charles M. Copple, Darryle Quincey, Eric T. Esterbrook, Leonard F. Reid and Louis A. Champoux, and by U.S. Pat. No. 5,468,104, granted Nov. 21, 1995, to Leonard F. Reid and Charles M. Copple. The radial expansion locks the nut holder against rotating but these systems require attachment of a nut to provide the wall insert with the internal threads.
There is a need for a method and apparatus for installing a fastener element with internal threads in an opening in a wall in such a way that the tubular rivet is restrained against rotating in response to a bolt being threaded into the fastener element. An object of the present invention is to provide such a method and apparatus.
According to an aspect of the invention, an internally threaded fastener element is inserted into a close fitting circular opening in a wall and is moved axially inwardly until a flange at its trailing end makes contact with the wall where it immediately surrounds the opening. The fastener element is provided with a tubular end portion that is positioned inside the opening when the flange is in contact with the wall. The fastener element is also provided with an annular sidewall region of reduced thickness that is positioned on the second side of the wall axially between the opening in the wall and the internal threads in the fastener element. A threaded end portion of a rod is inserted into the fastener element from the first side of the wall and is rotated to connect it to the internal threads in the fastener element. A tubular mandrel is provided in a surrounding relationship to the rod on the first side of the wall. The tubular mandrel has an outer diameter that is larger than a center opening in the tubular portion of the fastener element that is within the opening in the wall. The tubular mandrel also has an end portion that is adapted to enter into the center opening from the first side of the wall. The rod is retracted axially relatively into and through the mandrel, to cause the annular sidewall region of reduced thickness to buckle and form a second flange and move the second flange against the second side of the wall, so that the wall is held between the two flanges. Also according to the invention, the mandrel is moved axially into the center opening of the tubular portion of the fastener element that is in the opening. The mandrel is sized so that as it moves into the center opening it radially expands the tubular portion of the fastener an amount sufficient to firmly connect it to the sidewall of the wall opening and hold it against rotation in response to torque applied by a screw that this later screwed into the fastener element.
According to a further aspect of the invention, a motor is provided for rotating the rod for threading the threaded end portion of the rod into and unthreading it out from the internal threads in the fastener element.
Another aspect of the invention is to radially expand a tubular member within an opening in a wall, for connecting the member to the wall, by pushing an expansion mandrel axially into a center opening in the tubular portion while holding the tubular portion in the wall. The member is provided with a flange at its trailing end. The member is inserted into the opening in the wall and pushed forwardly until the flange contacts the wall. The member is held in the opening by inserting a rod through the mandrel, engaging the member with the rod on the second side of the opening, and pulling the rod while at the same time contacting the perimeter of the center opening with the mandrel.
According to another aspect of the invention, a tool is provided for installing into a wall opening, a fastener element having a tubular first end portion that is sized to fit snugly within the wall opening, a center opening having an entrance, and an end flange surrounding the entrance. The tool comprises an elongated rod having a longitudinal axis. The rod is adapted to be rotated about the longitudinal axis. The rod also has an outer end portion that is adapted to be inserted into the center opening and be connected to the fastener element. The tool includes a tubular mandrel that projects axially. A center opening extends through the mandrel and the rod extends through the center opening. The mandrel has an outside diameter that is larger than the center opening in the fastener element. The mandrel is movable axially back and forth along the rod, towards and away from the outer end portion of the rod.
The tool may also comprise an elongated tubular member within the housing that is movable back and forth endwise relative to the housing. This tubular member has an outer end and the mandrel is at this outer end. The elongated rod extends endwise from its inner end through the elongated tubular member and the tubular mandrel to its free end. Preferably, there is a piston inside the housing that is connected to the elongated tubular member and there are a pair of fluid chambers in the housing, one on each side of the piston. Fluid introduction into and removal from the fluid chambers cause the back and forth movement of the tubular member.
The tool may also comprise a tubular nose piece that surrounds and is concentric with the elongated tubular member. The tubular nose piece is movable endwise back and forth longitudinally along the elongated tubular member. Preferably also, there is a second piston inside of the housing that is connected to the tubular nose piece, and there is a pair of fluid chambers in the housing, one on each side of the second piston. Fluid introduction into and removal from the fluid chambers cause the back and forth movement of the tubular member.
These and other advantages, objects, and features will become apparent from the following best mode description, the accompanying drawings, and the claims, which are all incorporated herein as part of the disclosure of the invention.

Method and apparatus for connecting a fastener element to a wall