A system and method for identifying, locating, and managing inventory of sterilized medical devices located within a sealed sterilization case in preparation for a surgical procedure. Communication tags, such as radio frequency identification (RFID) and/or Global Positioning System (GPS) tags, are connected to the medical device and communicate information wirelessly. Information is obtained from the communication tags and sent to the database where it is compared with the information in the database. The results may be displayed on the interface thereby providing the user with information about the medical instruments contained in the sealed sterilization case without breaking the seal of the sealed sterilization case.

1. Field of the Invention
This invention relates to systems and methods for identifying, locating, and managing inventory of sterilized medical devices located within a sterilization case that is sealed with a wrap in preparation for a surgical procedure.
2. Related Art
Surgical procedures generally involve various sterilized instruments. Sterilization can occur by known techniques such as autoclaving or those utilizing substances such as ethylene oxide, vapor hydrogen peroxide, or ozone. Before sterilization, the surgical instruments are placed inside a sterilization case that is typically made from steel, aluminum, titanium, or plastic. A sterilization case also may be referred to as an instrument tray or instrument case. The sterilization case is then wrapped in a plastic sheet and sealed. The plastic normally allows particles, condensed water, water vapor, and other substances to leave the sterilization case but prevents foreign contaminants from entering the sterilization case. Upon completing the sterilization process, the sterilization case containing the medical instruments is still within the sealed wrap. Prior to the surgical procedure and in the sterile field of the operating room, the instruments are typically removed from the wrap and sterilization case, placed on a table, and counted to validate that all instruments needed for the particular surgical procedure are on the table.
The tracking and management of surgical instruments in hospitals, instrument management companies, and sterilization companies is important to the efficiency and safety of use of hand held medical or surgical instruments. Inventory tracking is difficult to manage given that the instruments pass through the purview of various parties in the supply chain. Most hospitals in the United States have from 3,000 to 5,000 different types of instruments which are organized into 300 to 600 different types of sets. The content of these sets changes frequently. Moreover, individual devices within these sets become damaged and then require repair or replacement. It is desirable to be able to identify an inventory of the medical instruments to facilitate repair and replacement of these instruments should they become broken or worn. Instruments also can be misplaced, which may remain unknown until the instruments are removed from the sterilization case and the wrap in the sterile field of the operating room prior to surgery. If one or more instruments needed for the surgery are missing, hospital personnel must open another sealed plastic wrap to retrieve the missing instruments or locate a replacement within the hospital. Considerable time is required searching the hospital for a replacement to obtain a complete set of necessary instruments, which often involves opening other sealed cases. In the meantime, a patient is under anesthetic in the operating theatre waiting to be treated at a cost of $100 per minute and can often be delayed by fifteen minutes whilst hospital staff search for missing instruments. Once the instruments are retrieved, the remaining instruments in the opened cases have to be re-sterilized. Many healthcare facilities do not have effective solutions in place for tracking and management of surgical instruments, which is likely to grow as more instruments are purchased from manufactures. However, there is an increasing trend towards healthcare companies providing additional value to hospitals by tracking the hospital's entire inventory and ensuring that instruments are in fact in the instrument tray.
Hospitals, instrument management companies, and sterilization companies often have difficulty tracking and managing surgical instruments as they pass through the purview of various parties in the supply chain. For instance, instruments are sometimes misplaced, which may remain unknown until the instruments are removed from the sterilization case and the wrap in the sterile field of the operating room prior to surgery. If one or more instruments needed for the surgery are missing, personnel must open another sealed plastic wrap to retrieve the missing instruments or locate a replacement within the hospital. Personnel associated with surgical preparation sometimes need to open several sealed cases before they obtain a complete set of necessary instruments or spend time searching the hospital or other facility for a replacement. Furthermore, the remaining instruments in the second sterilization case and those opened thereafter, even if not used in a surgical procedure, always must be sterilized again.
Tracking individual instruments to specific trays is very challenging because each individual instrument needs to be scanned to the tray to form a link between the instrument and the tray, which is a labor intensive process. The techniques used to track surgical instruments include manual counting, color-coding and memory devices, which are discussed in turn below.
Various methods of counting the surgical instruments are known but none are particularly efficient. Manual counting involves a skilled technician physically counting each instrument on the surgical instrument tray and then comparing the count result to an information sheet that provides an inventory list of instruments used in a particular surgery. This count is usually performed close to, but before, the scheduled surgery while the patient is either already on the surgical table or on their way to the surgical room. If there is a discrepancy between the count and inventory list, the person counting or their assistant must quickly determine which instrument is missing and where a suitable replacement may be located before the surgical procedure begins. This tracking technique is unreliable and labor intensive because significant time is required to count the instruments manually, determine if there is a discrepancy between the count and the inventory list, and locate a replacement instrument before the surgical procedure begins. This time is costly to both the instrument company and hospital and could needlessly delay surgery. In addition, there is a likelihood for human error in counting the instruments and comparing the count to the inventory list. Furthermore, the correct instruments for a particular surgical procedure may still be missing during surgery, forcing the surgeon to use a closely related, but incorrect, instrument to perform the procedure. Manually tracking medical instruments also requires that the surgical instruments be removed from the wrap and the sterilization case before they are counted and compared to the inventory list for discrepancies.
A less common approach to instrument tracking includes color-coding techniques to identify different surgical instruments. Others optically mark each instrument and later scan the instruments with a hand-held scanner that is connected to a data terminal to ascertain the history of that instrument. Such a method typically requires that the instrument be removed from the tray on arrival and scanned by humans, a method that is costly and time-consuming. In addition, colors can fade and a significant percentage of the population is color blind.
Other methods to count surgical instruments and compare to an inventory list involve electronic mechanisms. Data carriers such as memory devices are a more expensive alternative method for manually counting surgical instruments and comparing them to an inventory. Memory devices permit the linking of large amounts of data with an object or item. Memory devices typically include a memory and logic in the form of an integrated circuit and a mechanism for transmitting data to and/or from the device.
One such method utilizes an optical scanner, in communication with a computer and database, which reads an encoded optical pattern of a bar code attached to each surgical instrument. Individual surgical instruments may be identified by the encoded optical pattern of the attached bar code. The optical scanner usually converts the encoded optical pattern of a bar code into an electrical signal that represents an identification code associated in the database with a particular surgical instrument. The computer typically contains a memory with database information about each surgical instrument and correlates that information to the identification code. The computer may then be programmed to produce information to a user in a variety of formats useful in an inventory procedure.
An optical tag is one form of memory device, which relies on an optical signal to transmit data to and/or from the tag. The optical scanner converts the encoded optical pattern of a bar code into an electrical signal that represents an identification code associated in the database with a particular surgical instrument. Thus, individual surgical instruments may be identified by the encoded optical pattern of the attached bar code. There are a number of disadvantages to the use of optical tags. First, the size of a bar code is too large for placement on relatively small surgical instruments. Second, the time required to scan and inventory a group of medical instruments can be quite lengthy, which can needlessly delay a surgical procedure. Third, optical scanning techniques require the user to present the optical scanner in close proximity to and in the line of sight of the bar code on each surgical instrument and orient the scanning device appropriately to the bar code. Furthermore, each surgical instrument and attached bar code must be scanned individually. Finally, the optical scanning procedure is prone to human error. If the user does not orient the optical scanner correctly with respect to a bar code on a surgical instrument, the scanner could fail to read that item and it could be deemed missing when it is actually present in the surgical instrument group.
Another method for managing medical instrument locations prior to and during surgery utilizing electronic mechanisms involves attaching certain radio frequency identification (RFID) tags to surgical instruments and a reader that obtains information associated with the particular medical instrument through radio frequency. A second type of memory device is the radio frequency identification (RFID) tag, which typically includes a memory for storing data, an antenna, an RF transmitter and receiver or an RF transceiver to transmit data, and logic for controlling the various components of the memory device. RFID tags can either be passive or active devices. Active devices are self-powered, by a battery for example. Passive devices do not contain a discrete power source but derive their energy from an RF signal used to interrogate the RFID tag. A reader is used to obtain information associated with the particular medical instrument through radio frequency. The reader is in electrical communication with a computer system having a database of information about the inventory. After detecting the radio frequency signal from the RFID tag, the reader causes the computer system to change the data in the database to account for the presence of a particular inventory item. If each instrument was embedded with an RFID tag and the tray in which the instruments are placed is retrofitted with a RFID reader, instruments could be identified and logged the moment they are placed in the tray. RFID tags typically comprise an electronic circuit placed on small substrate materials. The electronic circuits contain encoded data and transmit or respond (actively or passively) with encoded or identifiable data as a radio frequency signal or a signature when an interrogation radio frequency signal causes the electronic circuit to transmit or respond (whether actively or passively). Some RFID tags are able to have their data modified by an encoded radio signal.
A reader is a radio frequency emitter/receiver or interrogator. In accordance with general RFID tag methodology, the reader interrogates RFID tags that are within its range by emitting radio frequency waves at a certain frequency. Each tag may respond to a unique set of interrogation frequencies. An RFID tag typically responds to an interrogation by emitting or responding with coded or identification information as a radio frequency signal or signature and this signal or signature (whether actively or passively) is detected by the reader. The reader is in electrical communication with a computer system having a database of information about the inventory. After detecting the radio frequency signal from the RFID tag, the reader causes the computer system to change the data in the database to account for the presence of a particular inventory item.
An RFID tag system has several advantages over manual counting and optical scanning systems. For instance, the RFID tag reader is not required to be aimed directly at a tag in order to detect a signal. An RFID tag system does not require the user to orient a reader with respect to a particular tag in order to obtain the information as the optical scanning system requires. An additional advantage of an RFID tag system is the capability of quickly performing an inventory of a large group of items by successively reading a tag associated with each item without requiring the user to perform multiple procedural steps. This saves time and expense relative to manual and optical scanning systems.
In theory, RFID tagging is an ideal solution for tagging individual instruments. However, it is also a very challenging proposition given current limitations with RFID technology. Any device attached to a medical device or surgical instrument must be capable of performing despite being attached to various metals. It is difficult to apply and read RFID tags on metallic alloys because they tend to either absorb or reflect RF signals. This is a problem because many surgical instruments and implants are metallic interfering with weak RF signals of either the reader or tag, thus reducing the system's read range. The sterilization case is also metallic preventing electromagnetic energy, such as a radio frequency signal, from entering or leaving the case. Thus, an RFID reader is unable to communicate with the RFID tags located inside the sterilization case and the instruments must be removed from the case, including breaking the sealed wrap, in order for the reader to determine the inventory of a particular group of instruments. If, after reading the removed medical instruments, the medical instrument group does not include an instrument necessary for the particular surgical procedure, hospital or medical instrument company representatives must break another sealed sterilization packet, remove the instruments from the case and read or interrogate the RFID tags of that group to find the instrument necessary to complete the first instrument group. This process includes high costs and time delays in preparing for a surgical procedure.
Tag reliability can be impacted by environmental factors such as humidity, radiation and temperature. Previously, commercial-off-the-shelf RFID tags could not withstand extreme temperatures without a temperature-resistant housing. For that reason, using them for items like surgical instruments which undergo an autoclave or dry heat sterilization cycle is complicated. Costs are presently very high for custom chips, and tags capable of surviving the temperatures in a sterilization cycle would have to pass very close to an RFID-reader.
Known RFID tag systems have been used to manage medical instrument locations prior to and during surgery. For instance, the individual instruments may be scanned prior to the surgery to ensure that all instruments needed for the procedure are present. Prior to completing the surgery, the surgical tray table may be scanned again to ensure that instruments are located on the tray table instead of inside the patient. Some RFID tag systems describe scanning the surgical cavity of the patient to check for the presence of any instruments prior to completing the surgery.
Previous and current RFID tag systems used to manage and inventory medical instruments require that surgical personnel break the sterilization seal of a group of instruments and remove the instruments from the packet before the reader reads medical instruments. This is because instruments are typically contained within a metallic sterilization case and the sterilization case prevents electromagnetic energy, such as a radio frequency signal, from entering or leaving the case. Thus, an RFID reader is unable to communicate with the RFID tags located inside the sterilization case and the instruments must be removed from the case, including breaking the sealed wrap, in order for the reader to determine the inventory of a particular group of instruments. If, after reading the removed medical instruments, the medical instrument group does not include an instrument necessary for the particular surgical procedure, hospital or medical instrument company representatives must break another sealed sterilization packet, remove the instruments from the case and read or interrogate the RFID tags of that group to find the instrument necessary to complete the first instrument group. This process includes high costs and time delays in preparing for a surgical procedure.
A medical instrument inventory and management system that allows personnel to read data regarding the individual medical instruments contained within a sealed sterilization case would decrease the time necessary to locate a particular instrument. In addition, determining the presence of particular medical instruments inside a sealed sterilization case could decrease the time and cost of preparing for a surgical procedure because breaking a second and additional sealed packets requires another cleaning, decontamination, and sterilization process. Furthermore, personnel could read the inventory of several packets and select the one with the correct instrument group for a particular medical procedure.
Further, there is a problem in locating missing instrument trays, implant trays, and devices. For example, a tray may be lost at a hospital and hospital personnel are not able to locate the tray in time for surgery. Another example would be the tray lost in delivery or sent to an incorrect facility.
Sometimes a surgeon does not know how to use an instrument correctly or know what the next step is in a complicated surgical procedure. An example may be a resident using an implant system in the middle of the night and not knowing whether to perform step A or step B in the surgical procedure.
Hospitals face significant costs in managing inventory. Currently, a sales representative must review the inventory and determine if the hospital has an adequate amount of each product. If the sales representative determines that inventory is low, then the sales representative places an order to replenish the stock.
It would be of significant benefit if the instrument trays and surgical instrument inventory could be tracked. Tracking assets, physical inventory, and other objects in a large-scale enterprise is a daunting task. Traditionally, this requires a manual, physical inventory that must be regularly repeated. Further, as assets move from place to place, or out of the control of the enterprise, the conventional process requires a time-intensive paperwork trail to track the movement of the assets.
This already-daunting task is made even more difficult when the assets being tracked are physically similar because in that case every specific serial number must be verified to conclusively identify the specific item.
Recently, for items such as shipping containers, RFID tags have been used to partially automate this process in a real-time location system (RTLS). In the common case, an asset with an attached RFID tag transmits a unique identifier, allowing an RFID tag reader to easily receive the transmitted ID number and thereby identify specific shipping containers.
An entirely different type of asset location is used for locating stolen vehicles. A commonly known system of this type is the "LoJack" system manufactured by the LoJack Corporation of Westwood, Mass., and described in U.S. Pat. Nos. 4,818,998, 4,908,629, 5,917,423, and 6,665,613, all of which are hereby incorporated by reference. In general terms, this type of system uses a remotely activated system to track a vehicle in motion, using transceivers installed in the target vehicle in combination with transceiver/detectors mounted on other vehicles. Typically, a LoJack system is used to track stolen vehicles. When a target vehicle is reported stolen, its transceiver is remotely activated, and thereafter police units that are specially equipped with transceiver/detectors can detect and locate the target vehicle.
LoJack is a form of an asset location system that utilizes a special FCC-allocated radio frequency (173.075 MHz), an older technology, very high frequency (VHF) signal. The LoJack transceiver is passive until activated by police radio towers, and specially equipped police cruisers with receivers must work together to triangulate and locate the target vehicle. LoJack does not utilize global positioning satellites (GPS) for location information.
Another type of long-range vehicle-tracking system uses GPS to identify the current location of a vehicle. In this case, a GPS receiver is mounted in the vehicle to determine the vehicle location, and a separate transmitter is used to send the location data to the person or entity tracking the vehicle. In the common ONSTAR system, cellular telephone technology is used to activate the GPS receiver and to transmit the location data to the ONSTAR service center. ONSTAR is a registered trademark of OnStar Corporation of Troy, Mich.
Goods shipped to a destination from a manufacturing plant, warehouse or port of entry are normally tracked to assure their timely and safe delivery. Tracking has heretofore been accomplished in part by use of various shipping documents and negotiable instruments, some of which travel with the goods and others of which are transmitted by post or courier to a receiving destination. This paper tracking provides a record which is completed only on the safe delivery and acceptance of the goods. However, there sometimes is a need to know the location of the goods prior to delivery or acceptance. Knowledge of the location of goods can be used for inventory control, scheduling and monitoring.
Shippers and/or distributors have provided information on the location of goods by tracking their vehicles and knowing what goods are loaded on those vehicles. Goods are often loaded aboard shipping containers or container trucks, for example, which are in turn loaded aboard railcars. Various devices have been used to track such vehicles. In the case of railcars, passive radio frequency transponders mounted on the cars have been used to facilitate interrogation of each car as it passes a way station and supply the car's identification. This information is then transmitted by a radiated signal or land line to a central station which tracks the locations of cars. This technique, however, is deficient in that whenever a particular railcar remains on a siding for an extended period of time, it does not pass a way station. Moreover, way station installations are expensive, requiting a compromise that results in way stations being installed at varying distances, depending on the track layout. Thus, the precision of location information varies from place to place on the railroad.
Recently, mobile tracking units have been used for tracking various types of vehicles, such as trains. Communication has been provided through the use of cellular mobile telephone or RF radio link. Such mobile tracking units are generally installed aboard the locomotive which provides a ready source of power. However, in the case of shipping containers, container truck trailers and railcars, a similar source of power is not readily available. Mobile tracking units which might be attached to containers and vehicles must be power efficient in order to provide reliable and economical operation. Typically, a mobile tracking unit includes a navigation set, such as a GPS receiver or other suitable navigation set, responsive to navigation signals transmitted by a set of navigation stations which may be either space-based or earth-based. In each case, the navigation set is capable of providing data indicative of the vehicle location based on the navigation signals. In addition, the tracking unit may include a suitable electromagnetic emitter for transmitting to a remote location the vehicle's location data and other data acquired from sensing elements on board the vehicle. Current methods of asset localization require that each item tracked be individually equipped with hardware which determines and reports location to a central station. In this way, a tracked asset is completely "ignorant" of other assets being shipped or their possible relation to itself. In reporting to the central station, such system requires a bandwidth which scales approximately with the number of assets being reported. The aggregate power consumption over an entire such system also scales with the number of assets tracked. Further, because both the navigation set and the emitter are devices which, when energized, generally require a large portion of the overall electrical power consumed by the mobile tracking unit, it is desirable to control the respective rates at which such devices are respectively activated and limit their respective duty cycles so as to minimize the overall power consumption of the mobile tracking unit.
Most present-day asset tracking systems are land-based systems wherein a radio unit on the asset transmits information to wayside stations of a fixed network, such as the public land mobile radio network or a cellular network. These networks do not have ubiquitous coverage, and the asset tracking units are expensive. A satellite-based truck tracking system developed by Qualcomm Inc., known as OMNITRACS, is in operation in the United States and Canada. This system requires a specialized directional antenna and considerable power for operation, while vehicle location, derived from two satellites, is obtained to an accuracy of about one-fourth kilometer. U.S. Pat. No. 5,129,605 to Burns et al., incorporated by reference herein, describes a rail vehicle positioning system for installation on the locomotive of a train and which uses, to provide input signals for generating a location report, a GPS receiver, a wheel tachometer, transponders, and manual inputs from the locomotive engineer.
In an asset tracking system disclosed in U.S. Pat. No. 5,651,800, entitled "Local Communication Network for Power Reduction and Enhanced Reliability in a Multiple Node Tracking System" by Welles et al. and in U.S. Pat. No. 5,588,005 entitled "Protocol and Mechanism for Primary and Mutter Mode Communication for Asset Tracking" by Ali et al., both of which are incorporated herein by reference, a tracking system based on a "mutter" mode local area network is used to generate data that is transmitted to a central station. In this asset tracking system, there are two modes of communication. One mode is communication between the central station and the tracking units, which is usually via satellite. The second mode is a local area network, referred to as the "mutter" mode, between tracking units. One of the tracking units, denoted the master unit, communicates with the central station.
One of the chief challenges in using the first mode of communication is to devise a protocol for the communications that will provide efficient use of the communication facilities and respect the special sensitivities of the reporting scenario. Such protocol should meet the following guidelines:
1. The protocol should be two-way, thereby supporting transmission to and from a central station.
2. The protocol must accommodate a large number of assets and be scalable so that assets can be added and deleted without impacting normal service.
3. The protocol must accommodate variable length messages. The variable length may arise from a number of considerations; for example, the individual asset may have extra sensor data to report in addition to its location.
4. The protocol must have a chatter suppression feature to allow selective turn-off of a specific malfunctioning asset's transmitter.
5. The protocol must function efficiently if used over an extremely long path such as is implied by use of a geostationary satellite.
6. The protocol must allow encryption or a privacy feature to be added later without significantly impacting the capacity.
7. The protocol must be sufficiently robust to allow an asset to enter the system at any time without knowledge that cannot be gleaned following its entry into the system, and must tolerate occasional transmission errors and not be unstable but degrade gracefully under additional load.
8. The protocol must not require the assets to be receiving all the time but accommodate a duty cycle significantly less than 100% for periods of monitoring communication frequencies.
The protocol must be designed to be easily adjusted and nominally reprogrammable to allow presentation of its efficiency as the operational scenario matures.
The term "telematics" is often used to refer to automobile based asset tracking systems that combine GPS satellite tracking and wireless communications for automatic roadside assistance and remote diagnostics.
Referring to FIG. 1, there is shown a block diagram illustrating a general telematics system 100 in accordance with the prior art. Typically, a telematics system 100 includes services 110, platforms 120, networks 130, auto/freight sector clients 140, and positioning technologies 150. The services 110 provided by the telematics system 100 may include automatic roadside assistance, accident notification, traffic information, diagnostics, mobile Internet access, fleet management, and navigation. The platforms 120 on which the telematics system 100 may update may include servers, gateways, and billing and customer-care call centers. The networks 130 by which communications are provided may include voice, short messaging system ("SMS") messaging, and wireless application protocol ("WAP"). The auto/freight sector clients 140 serviced by the telematics system 100 may include passenger vehicles, trucks, freight, public safety applications. Typically, telematics systems 100 perform applications including vehicle or equipment (i.e., asset) location, driver concierge services, fleet management, and navigation/traffic information services.
Typically, an asset tracking device or module is installed in the vehicle to be tracked. The location of the device is determined by the telematics system 100 using a positioning technology 150, such as GPS or time difference of arrival ("TDOA"). The location information is then provided to an application to service a customer.
Briefly, the GPS was developed by the U.S. Department of Defense and gradually placed into service throughout the 1980s. The GPS satellites constantly transmit radio signals in L-Band frequency using spread spectrum techniques. The transmitted radio signals carry pseudorandom sequences which allow users to determine location on the surface of the earth (within approximately 100 feet), velocity (within about 0.1 MPH), and precise time information. GPS is a particularly attractive navigation system to employ, being that the respective orbits of the GPS satellites are chosen so as to provide world-wide coverage and being that such highly-accurate radio signals are provided free of charge to users by the U.S. government. The main problem with current GPS technology is the requirement for an unobstructed view of the sky for communication with GPS satellites. Its advantage is that is can provide a location anywhere in the world without any additional infrastructure on the ground. Improved receiver performance and signal processing and new technologies, like "Enhanced GPS," will provide locations where traditional GPS would fail.
On the other hand, TDOA uses the existing cellular network infrastructure to determine location. Referring to FIG. 2, there is shown a flow diagram illustrating a typical TDOA process 200. The process requires signal timing information from at least three different antenna sites. At step 1, a handset or vehicle places a call (e.g. a 911 call). At step 2, antennae receive the signal from the handset or vehicle and pass it to a carrier's mobile switching office. At step 3, TDOA equipment measures the difference in the time the cellular radio signals arrive at the antenna sites and translate that data into location data (i.e., longitude and latitude data). At step 4, the carrier forwards voice call and location data to a Public Safety Answering Point ("PSAP"). The use of TDOA is typically restricted to areas where coverage from multiple towers is available.
The communications networks 130 for linking tracking devices to platforms 120 to provide services 110 to customers include cellular and telephone networks. With respect to cellular networks, network providers typically make use of the Advanced Mobile Phone System ("AMPS") control channel frequencies for the transfer of small data packets. The use of the cellular network control channel provides more robust communication than cellular voice traffic so that it is possible to communicate with devices located in places where ordinary cell phones have marginal or intermittent voice coverage. Clients of these virtual carriers can make use of a TCP/IP data link to connect their operations centre to the virtual carrier network which then provides continent wide coverage through cellular service providers.
For example, in U.S. Pat. No. 6,131,067, to Girerd, et al, a client-server based system is described in which the location of a tracking device is determined using GPS information. This location is then reported to a user via the Internet. The entire disclosure of U.S. Pat. No. 6,131,067 is hereby incorporated by reference.
It would be of significant benefit if existing telematics systems could be adapted for tracking medical devices and/or sterilization cases. Medical devices may include medical implants, medical instruments, and other components.
There is a need in the art for a system and method for locating missing sterilization cases and/or medical devices. Further, there is a need in the art for a system that provides instruction to medical personnel on how to perform certain procedures or how to use certain medical instruments. Finally, there is a need for continued improvement in the area of hospital inventory management.

System and method for tracking surgical assets


Disclosed is a semiconductor device comprises a semiconductor substrate having on its surface a trench, a polycrystalline semiconductor film formed inside the trench, a diffusion layer deposited on a surface region of the semiconductor substrate, and a metal semi-conductor nitride layer interposed between the diffusion layer and the polycrystalline semiconductor film, the metal semiconductor nitride layer including a metal, nitrogen and a semiconductor constituting the semiconductor substrate, and electrically connecting the polycrystalline semiconductor film with the diffusion layer.

1. Field of the Invention
This invention relates to a semiconductor device and a method for manufacturing the semiconductor device, and in particular, to a semiconductor device comprising a trench capacitor, and source/drain diffusion layer electrically connected with the trench capacitor, and a method for manufacturing such a semiconductor device.
2. Description of the Related Art
FIG. 1 shows a cross-sectional view of a DRAM cell having a trench capacitor according to the prior art. Referring to FIG. 1, reference numeral 81 denotes a monocrystalline p-type silicon substrate, 82 a trench capacitor, 83 a buried n-type well, 84 a p-type well, 85 n-type source/drain diffusion layer, 86 a gate insulating film, 87 a gate electrode, 88 an element-isolating insulating film, and 89 an insulating film.
The trench capacitor 82 is constituted by an n-type diffusion layer 90 (plate electrode), a capacitor insulating film 91 and an n-type polycrystalline silicon film 92 (storage node electrode).
On the n-type polycrystalline silicon film 92, there is deposited an n-type polycrystalline silicon film 93 which is directly connected with the n-type source/drain diffusion layer 85. Namely, the trench capacitor 82 is electrically connected with the n-type source/drain diffusion layer 85 through the n-type polycrystalline silicon film 93 functioning as a connecting portion.
Since the n-type source/drain diffusion layer 85 is monocrystalline, there is a possibility that the n-type polycrystalline silicon film 93 epitaxially grows with the source/drain diffusion layer 85 being utilized as a seed crystal during a heating step in the DRAM process. This heating step is performed in a step of forming a passivation film subsequent to the steps of forming the trench capacitor 82 and an MOS transistor for instance.
If the n-type polycrystalline silicon film 93 epitaxially grows in this manner, stress is caused to generate inside the resultant semiconductor elements, thereby giving rise to the generation of crystal defects inside the substrate. The crystal defects of this kind may become a cause for the generation of a leak current. The quantity of electric charge stored in the capacitor generally decrease as the degree of integration of a DRAM increases. Therefore, the generation of the aforementioned leak current cannot be disregarded particularly in the case of a highly integrated DRAM which will be going to be developed from now on.
As one of the means for preventing the generation of the aforementioned leak current, it may be conceivable to employ a DRAM cell as shown in FIG. 2. The DRAM cell shown in FIG. 2 is featured in that the n-type polycrystalline silicon film 93 is indirectly connected via a silicon nitride film 94 with the source/drain diffusion layer 85. As a result, due to the presence of the silicon nitride film 94 functioning as a barrier, the source/drain diffusion layer 85 is no longer capable of functioning as a seed crystal, thus making it possible to prevent the n-type polycrystalline silicon film 93 from being epitaxially grown.
Since the silicon nitride film 94 is one kind of insulating film, this silicon nitride film 94 is required to be extremely thin in order to sufficiently secure an electric connection between the n-type polycrystalline silicon film 93 and the source/drain diffusion layer 85.
However, even if it is possible to make the silicon nitride film 94 extremely thin, the silicon nitride film 94 is still permitted to function as an insulating film, so that it is impossible to avoid an increase of contact resistance between the trench capacitor 82 and the source/drain diffusion layer 85.
As mentioned above, in the case of the conventional DRAM cell having a trench capacitor, the trench capacitor is electrically connected, via an n-type polycrystalline silicon film or an n-type polycrystalline silicon film/silicon nitride film, with source/drain diffusion layer.
In the case of the former, due to the epitaxial growth of the n-type polycrystalline silicon film (storage node electrode) constituting a trench capacitor, a stress, which is a cause of a leak current generates inside the resultant semiconductor elements, thus causing the generation of a leak current. On the other hand, in the case of the latter, it would be impossible to prevent an increase in contact resistance between the n-type polycrystalline silicon film and the source/drain diffusion layer.

Semiconductor device and method of manufacturing the same


A metallic ring is made of two metals, wherein one metal forms a major arcuate portion and the other a minor arcuate portion of the ring, thereby forming a thermocouple-type structure as a result of the two inter-metallic junctions. The metallic ring supports a surface plasmon whose energy is matched to the energy, i.e. wavelength, of an incident light beam so that the oscillating electromagnetic field of the light resonates with the plasmon. The resonating plasmon causes a temperature difference to arise between the two inter-metallic junctions in the ring. The different Seebeck coefficients of the two metals results in the temperature difference causing a net current to flow around the ring, which in turn generates a magnetic field. Such a thermoelectric metamaterial ring transforms high frequency optical energy into long duration magnetic radiation pulses in the terahertz range. Applications of these devices include high density magnetic recording, magnetic field spectroscopy, and efficient terahertz radiation sources.

The invention relates to devices for generating magnetic fields.
Magnetic recording requires relatively high magnetic fields to be produced locally in order to fix the orientation of small magnetic domains on the surface of a magnetic disk. The demand is for ever-increased surface density coupled with stability of the magnetic domains, so once data is written it does not change. These requirements effectively mean that the ideal magnetic material should have high coercivity. However, the higher the coercivity, the greater the magnetic field required to set the domain orientation and hence write a bit of data.
Longitudinal magnetic recording (LMR) is the conventional approach for recording data on magnetic discs. Magnetic domains are aligned with the plane of the magnetic disc and the writing element is formed by the open poles of a ring magnet arranged sideways above the recording layer, referred to as a "ring" writing element. Longitudinal recording has an estimated density limit of 100-200 Gbits per square inch. The super-paramagnetic effect is performance limiting. Stronger magnetic fields are required to record data on materials with high coercivity and small domain size.
Perpendicular magnetic recording (PMR) is a more recently developed approach for recording data on magnetic discs. Magnetic domains in the recording layer are aligned perpendicular to the plane of the magnetic disc. An additional soft magnetic layer is arranged underneath the recording layer and cooperates with a monopole writing element to direct magnetic field directly down through the recording layer. PMR can produce higher data densities than LMR, perhaps by a factor of 5.
Because magnetic field generators are at their limit, an enhancement that has been proposed for magnetic recording is so-called heat assisted magnetic recording (HAMR). HAMR exploits the fact that the coercivity of a magnetic material and hence its switching threshold reduces with increasing temperature, so by heating the disc locally in the region where the data is to be written, the magnetic field required to effect writing is reduced. Local heating can be provided by a focused laser beam. In 2009, HAMR devices achieved a density of 250 Gbits per square inch. It is predicted that data storage densities of 1 terabit per square inch or more will be achievable with HAMR. Mainstream commercial adoption of HAMR is expected by 2015.


A method of depth detection based on a plurality of video frames includes receiving a plurality of input frames including a first input frame, a second input frame, and a third input frame respectively corresponding to different capture times, convolving the first to third input frames to generate a first feature map, a second feature map, and a third feature map corresponding to the different capture times, calculating a temporal attention map based on the first to third feature maps, the temporal attention map including a plurality of weights corresponding to different pairs of feature maps from among the first to third feature maps, each weight of the plurality of weights indicating a similarity level of a corresponding pair of feature maps, and applying the temporal attention map to the first to third feature maps to generate a feature map with temporal attention.

There has been recent interest in the estimation of the real-world depth of elements in a captured scene. Accurate depth estimation allows for the separation of the foreground (close) objects from the background (far) objects in a scene. Accurate foreground-background separation allows one to process captured images to emulate effects such as the Bokeh effect, which refers to the soft out-of-focus blur of the background. The Bokeh effect may be created by using the right settings in expensive cameras with fast lens, and wide apertures, as well as by adjusting the camera closer to the subject and the subject further away from the background to emulate the shallow depth-of-field. Thus, accurate depth estimation may allow processing images from non-professional photographers or cameras with smaller lenses (such as mobile phone cameras) to obtain more aesthetically pleasant images with the Bokeh effect which focus on the subject. Other applications of accurate depth estimation may include 3D object reconstruction and virtual reality applications, where it is desired to change the background or the subject and render them according to the desired perceived virtual reality. Other applications of accurate depth estimation from the captured scene may be in car automation, surveillance cameras, self-driving applications, and enhanced safety by improving the object detection accuracy and estimation of its distance from the camera.
The above information disclosed in this Background section is only for enhancement of understanding of the present disclosure, and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.

Video depth estimation based on temporal attention


A security and monitoring device for an emergency exit door has an electrical control device 15 with a microprocessor, an LED current-status display device 11, an emergency off switch device 3, and a key switch device 12 are located in use in a door terminal 20. In order to obtain an especially simple design as well as advantages in assembly and maintenance, provision is made that door terminal 20 is modular in design and control device 15, status display device 11, emergency off switch device 3, and key switch device 12 are designed as modules. These modules are located in under-plaster switch boxes so that an under-plaster arrangement of the terminal is obtained.

This application claims priority of DE 29904141.7, filed Mar. 6, 1999, in Germany, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a security and monitoring device for a door or window system as an emergency exit system with at least one window light designed as a door light or window light.
Security and monitoring devices of this kind are so-called RWS systems, in other words escape route systems. They are built into door or window systems in escape and rescue routes. They are emergency exits which are in the closed position during normal operation and are intended to create an exit only in emergencies. Such RWS systems are known for example from German Patent Document DE 196 25 237 A1. The disadvantage of these known devices is that the so-called door control centers mounted near the door, which as a rule have an LED current state display, a key switch for turning the entire device on or off with authorization, and an emergency off switch for shutting off the electrical door-locking device in emergencies, are relatively voluminous. Frequently, the door control center located next to the door also contains an electrical control device with a microprocessor that controls the functions of the security and monitoring device.
RWS door control centers with this design are usually installed in voluminous housings located next to the door and mounted on the wall (product brochure from GEZE "The New RWS").
A likewise relatively voluminous RWS door terminal is known from German Patent Document DE 196 52 348. It has a surface-mounted housing. The key switch unit is designed to be replaceable so that either a conventional mechanical key switch or an electronic code pad or a read device for transponders can be placed in the door terminal.
It is also known from practice to install such RWS door control centers in a correspondingly voluminous housing sunk into the wall under the plaster, as shown for example in the product brochure from the effeff company "Escape Route Guidance Technology" on pages 16 and 17 and in the product brochure from the Dorma company "Door Terminal TL and Accessories" on pages 7 and 8.
It is also known from practice to install operating switches under the plaster in buildings.
Thus, it is known to install electrical light switches and sockets under the plaster.
In addition to the location of electrical switches under the plaster, it is also known to install the operating and control elements for automatic door drives individually under the plaster (product brochure "Plus Point Control Elements" from the GEZE company, pages 7, 5, and 3).
It is also known to mount a programmed timer and operating switches for a control of a shutter drive for windows in a wall under the plaster (http://www.domgy.de/home/gerger/hou/hou2000.shtm "Modernization for Roller Blinds," Somfy company.
An operating unit for a building control system is known from German Patent Document DE 195 41 499 designed as a unit to go beneath the plaster. The operating unit is connected with the building control system through a bus coupler and manual commands and/or measured values can be transmitted to it. The operating unit is provided for accommodation in an individual box under the plaster. A device for arming and disarming an alarm system is known from German Patent Document DE 196 41 022 in which stationary read units and the corresponding antennas are accommodated in a plurality of spatially separate individual boxes beneath the plaster. The read units act together with the alarm system to arm and disarm through switches connected between them.
An under-plaster modular system for an intercom system is known from German Patent Document DE 40 09 190. This under-plaster modular system consists of an under-plaster box designed especially for this application, one or more modular housings, and one or more intermediate housings. The modular housings contain the intermediate housings in the form of frames or boxes into which electrical PC boards or a correspondingly designed device housing can be inserted. The intermediate housings or the instrument housings have electrical connecting buses designed in complementary fashion for the electrical terminals of the modular housing so that when the intermediate housing or the device housing is inserted into the modular housing, the electrical connection is automatically created.
A goal of the invention is to design a security and monitoring device of the type recited at the outset so that it is simpler and unobtrusive.
This goal is achieved by providing a security and monitoring device for a door or window system, preferably an emergency exit system with at least one panel constructed as a door panel or window panel, with a preferably electrical sensor device which determines when the panel is operated in the opening direction and/or when a manual actuating element mounted on the panel is actuated or, when the panel is not in the closed position, a specified opening angle is preferably exceeded, with an electrical alarm display device with acoustic and/or optical alarm display element indicating when the panel is actuated in the opening direction and/or is impacted and/or when a manual actuating element mounted on the panel is actuated or when the panel is not in the closed position, a specified opening angle is preferably exceeded, with an electrical control device preferably with a microprocessor, that processes the signals, preferably electrical signals, from the sensor device and controls the electrical alarm display device, preferably with an electrically switchable locking device for locking and unlocking the panel with the locking device preferably being connected with a manually operable emergency off switch, preferably with a key switch device for authorized switching on and off and/or control of the functions of the security and monitoring device, preferably of the alarm display device and/or the electrically switchable locking device of the panel, preferably with an electrical current-status display device which indicates the position of the door or window panel and/or the current functional status of the security and monitoring device, preferably with an LED display device, wherein the current-status display device and/or the key switch device and/or the emergency off switch and/or the electrical control device and/or the alarm display device and/or a structural unit are designed from a plurality of these components as an add-on module or modules for reception in an under-plaster switch box, with several under-plaster switch boxes being arranged side by side in a row, with a separate add-on module being receivable in each under-plaster switch box.
By locating the various components of the door central control in switch boxes under the plaster, a depressed and unobtrusive arrangement is obtained. With a modular design for the components as a module with a uniform acceptance cross section for use in the corresponding receiving area of the under-plaster switch boxes, further advantages are obtained, namely technical advantages in installation and repair as well as the general advantages of a modular system. The system with a modular design forms a kit system that allows any combination and subsequent expansion using individual modules.
The under-plaster switch box can be designed with standard under-plaster switch boxes. This considerably simplifies installation of the system in buildings and it is also possible to install it subsequently without an anesthetic door terminal next to the door that creates a disturbing visual impression.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

Security and monitoring device for an emergency exit system having a door light or a window light


A cooking appliance according to an embodiment of the present invention may comprise: a case in which a cooking chamber is formed; a door for opening or closing the front opening of the case; a steam generating device mounted to the outer surface of the case; and a steam supply tube for connecting the steam generating device to the cooking chamber, wherein the steam generating device includes: a housing fixed to the case; a drawer which can be pushed into and pulled out of the housing and is filled with water for steam generation; and an induction unit installed at the bottom of the housing so as to heat water filled in the drawer by using electromagnetic induction.

Generally, a cooking appliance is a household appliance for cooking food and includes an electric oven, a microwave, and the like.
In particular, an electric oven is a device which cooks by confining water vapor generated from food together with heat in the oven and then heating to high temperature.
Recently, many cooking appliances including a steam supply device for supplying steam into a cooking space, such as a steam oven, have been released. By supplying steam into the cooking space, various dishes including steamed dishes are possible.
As the related art, Korean Patent Publication No. 2010-0009855 (Jan. 29, 2010) discloses a cooking appliance equipped with a steam supply device. The cooking appliance disclosed in the related art includes a steam generating device, a water supply tank for supplying water to the steam generating device, and a heater fixedly mounted inside the steam generating device.
However, the cooking appliance with the steam supply device disclosed in the related art has the following disadvantages.
First, since the steam generating device and the water tank for supplying water to the steam generating device should be provided separately, there is a disadvantage that the volume of the cooking appliance is large.
Second, since the steam generating device and the water tank must be provided separately, there is a disadvantage that the degree of freedom of design inside the cooking appliance is not large.
Third, since the heater has a structure which is fixed inside the steam generating device, there is a disadvantage that the cleaning of the steam generating device is not easy. In other words, in the conventional steam generating device, since the heater is submerged in water, scales are formed around the heater or on the inner wall of the steam generating device.
However, descaling is substantially impossible because it is difficult to disassemble the heater or disassemble the steam generating device. As a result, there is a disadvantage that the thermal efficiency of the steam generating device is remarkably lowered because the accumulated scale cannot be removed as the service life of the cooking appliance becomes longer.
Fourth, according to the conventional structure in which the heater is mounted inside the steam generating device and the heater is submerged in water, when water level in the steam generating device is lowered and the heater is exposed over the water surface, there is a disadvantage that the heater is overheated and there is a high risk of fire.


An infrared solid state imaging device includes: a first PN junction diode has a first shortest length that is a shortest length from a first junction surface to a second junction surface; a PN junction diode has a second shortest length that is a shortest length from the second junction surface to a third junction surface, the second shortest length being different from the first shortest length; an insulating film serving as an element isolation region which establishes electrical isolation between a first region of the first PN junction diode and a fourth region of the second PN junction diode, and so on; and a metal wire provided on a second region of the first PN junction diode and a third region of the second PN junction diode, wherein the first PN junction diode and the second PN junction diode are connected in series.

An infrared solid state imaging device including thermal infrared detection elements as pixels absorbs infrared rays, converts the infrared rays into heat, outputs a temperature change caused by the heat as an electrical signal, and detects the infrared rays. The infrared solid state imaging device including thermal infrared detection elements can be downsized because it does not require a refrigerator. In particular, attention is focused on a thermal infrared solid state imaging device that uses silicon PN junction diodes which can be manufactured by a conventional semiconductor manufacturing process as infrared detection elements, and detects a temperature change in the amount of a voltage drop in a forward direction thereof.
However, in the thermal infrared solid state imaging device which detects a temperature change in the amount of a voltage drop in the forward direction of the silicon PN junction diodes, the temperature change rate of a junction current in the forward direction is small, when compared with other infrared detection elements that adopt a method of detecting a temperature change in the resistance value of vanadium oxide, for example, and a sufficient sensitivity for detecting infrared rays cannot be obtained. Accordingly, an infrared solid state imaging device that improves sensitivity for detecting infrared rays by adopting a hollow structure that isolates a thermoelectric converter provided with silicon PN junction diodes from a substrate having a large heat capacity, or by connecting a plurality of silicon PN junction diodes in series, has been proposed.
In addition, an infrared solid state imaging device including infrared detection elements in which, in order to connect a plurality of silicon PN junction diodes in series, N type regions and P type regions of the silicon PN junction diodes are alternately placed to be in contact with one another, an electrode is provided between the regions of the adjacent silicon PN junction diodes, and thereby the plurality of silicon PN junction diodes are connected in series, has been proposed (see PTL 1, for example).
In addition, an infrared solid state imaging device including infrared detection elements in which, of a plurality of silicon PN junction diodes connected in series, at least some PN junction diodes have a bent shape for the purpose of placing as many PN junction diodes as possible in a limited area, has been proposed (see PTL 2, for example).


A method for reducing the surface roughness of a metal layer is provided. In some embodiments, the method may include polishing the metal layer to a level substantially above any layers arranged directly beneath the metal layer. In some cases, the semiconductor topography comprising the metal layer may be substantially absent of any material laterally adjacent to the metal layer during polishing. In either case, a semiconductor topography having a metal layer with a mean surface roughness less than the mean surface roughness obtained during the deposition of the metal layer may be obtained. As such, the method may include reducing the mean surface roughness of a metal layer. For example, the method may include reducing the mean surface roughness of a metal layer by at least a factor of ten.

1. Field of the Invention
This invention relates to semiconductor device manufacturing, and more particularly, to a method for fabricating a metal layer with a substantially smooth surface.
2. Description of the Related Art
The following descriptions and examples are not admitted to be prior art by virtue of their inclusion within this section.
In most cases, a material may include a plurality of peaks and valleys upon its surface, which are associated with the surface roughness of the material. Such peaks and valleys may be visible by the naked eye or through an optical microscope, an electron microscope, or an atomic force microscope (AFM). In either embodiment, the surface roughness of a material may be characterized by the vertical distances between the bases of valleys and crests of their adjacent peaks. Since the dimensions of peaks and valleys may differ across a surface, calculating a statistical mean of a plurality of surface roughness measurements may yield a roughness that is more representative of the entire surface. For example, in some embodiments, an average of a plurality of surface roughness measurements may be calculated to produce a statistical mean of a material. In other embodiments, a root mean square of a plurality of surface roughness measurements may be calculated to produce a statistical mean of the material. In general, xe2x80x9croot mean squarexe2x80x9d may be referred to as a measure of the magnitude of a set of numbers or measurements.
In some cases, the surface roughness of one or more layers within a semiconductor topography may affect the operation of a device formed from such a topography. For example, in cases including magnetic random access memory (MRAM) devices, layers with relatively rough surfaces may undesirably cause a junction within a device to breakdown at a relatively low voltage. In particular, relatively rough surfaces of layers within MRAM devices including magnetic tunneling junctions (MTJ) may cause a breakdown of the junction at a low voltage. In some cases, breakdown at a relatively low voltage may cause the device to frequently malfunction, thereby decreasing the reliability and/or yield of the device. In addition or alternatively, the threshold voltage by which the device is activated may be lower and thus, the junction breakdown may inhibit the entire operation of the device in some cases. In general, the breakdown of a MTJ may be attributed to an uneven tunneling layer within the junction. Since tunneling layers within MTJs are typically very thin (e.g., approximately 15 angstroms or less), the unevenness of such a layer may be caused by relatively rough surfaces of underlying layers. Consequently, it may be beneficial to deposit a layer with substantially smooth surfaces under such a tunneling layer.
Conventional deposition processes, however, have limited capability to produce layers with substantially smooth surfaces. In particular, deposition techniques used in the semiconductor fabrication industry typically produce layers with relatively rough topographies. For example, conventional deposition techniques may yield a root mean square surface roughness that is greater than approximately 100 angstroms and in some cases, greater than approximately several thousand angstroms. xe2x80x9cRoot mean squarexe2x80x9d may refer to a result of a statistical calculation correlating a plurality of measurements as described above. Moreover, the accumulation of layers with such surface roughnesses may cause an upper layer to have an even greater surface roughness than may be produced by a particular deposition technique.
Therefore, it would be desirable to develop a method for fabricating semiconductor layers with substantially smooth surfaces. In particular, it may be advantageous to develop an MRAM device, which includes substantially smooth layers underlying a tunneling layer. Consequently, a method for reducing the likelihood of junction breakdown within a MRAM device may be developed.
The problems outlined above may be in large part addressed by a method for reducing the surface roughness of a metal layer. In particular, a method is provided for reducing the mean surface roughness of a metal layer. In some embodiments, the method may include polishing the metal layer to a level substantially above any layers arranged directly beneath the metal layer. In some cases, the semiconductor topography comprising the metal layer may be substantially absent of any material laterally adjacent to the metal layer during polishing. In either case, a semiconductor topography having a metal layer with a mean surface roughness less than the mean surface roughness obtained during the deposition of the metal layer may be obtained. For example, a metal structure with a mean surface roughness less than approximately 10 angstroms may be obtained.
In yet other embodiments, the method may include depositing a fill layer upon a metal layer and subsequently polishing the fill layer. In some cases, polishing the fill layer may form a surface which includes portions of the metal layer and portions of the fill layer residing above the metal layer. In this manner, a semiconductor layer may be formed with fill material arranged around and within a plurality of peaks and valleys associated with the surface roughness of the metal layer. In such an embodiment, an upper surface of the fill layer may be substantially level with at least one of the peaks. In other cases, polishing the fill layer may include forming a surface in which the fill layer is arranged above an upper boundary of the metal layer-fill layer interface. In such an embodiment, the thickness of the fill layer arranged above the upper boundary may be less than the thickness of the interface.
As stated above, some embodiments of the method described herein may include polishing a metal layer arranged across approximately an entirety of a semiconductor topography to a level substantially above any layers arranged directly beneath the metal layer. In particular, the method may include depositing a metal layer upon a semiconductor topography, polishing the metal layer, and terminating the polishing process at a level substantially above any layers arranged directly beneath the metal layer. In some cases, the semiconductor topography comprising the metal layer may be substantially absent of any material arranged laterally adjacent to the metal layer during the polishing process.
In either embodiment, the polishing process may include removing an upper portion of the metal layer such that no underlying layer is exposed. In some cases, polishing the metal layer may include removing between approximately 100 angstroms and approximately several thousand angstroms of the metal layer. In other embodiments, polishing the metal layer may include removing less than approximately 100 angstroms. In addition, in some cases the method may include patterning the metal layer. For example, in some embodiments, the method may include patterning the metal layer prior to the polishing process. In other embodiments, the method may include patterning the metal layer subsequent to the polishing process. In such an embodiment, the method may further include depositing a layer upon the polished metal layer prior to the patterning process. In general, the metal layer may include any metallic material, such as, but not limited to, aluminum, copper, tantalum, tungsten, titanium, or a metal alloy thereof. In addition or alternatively, the metal layer may include a metal nitride material, such as, but not limited to, titanium nitride or tungsten nitride.
In some embodiments, the method may include measuring a mean surface roughness of the metal layer subsequent to polishing the metal layer. In particular, measuring the mean surface roughness may include calculating an average surface roughness, a root mean square surface roughness, or any other statistical mean surface roughness of the metal layer. In some cases, the method may further include re-polishing the metal layer when the measured mean surface roughness is above a predetermined value. In this manner, a lower mean surface roughness may be obtained. In either case, polishing the metal layer may include reducing the mean surface roughness of the metal layer. For example, in some embodiments, polishing the metal layer may include reducing the mean surface roughness of the metal layer by a factor of at least approximately ten. More particularly, polishing the metal layer may include reducing the mean surface roughness of the metal layer by a factor between approximately ten and one hundred. In yet other embodiments, polishing the metal layer may include reducing the mean surface roughness of the metal layer by a factor of approximately fifty. In either embodiment, reducing the mean surface roughness may include reducing an average surface roughness, a root mean square surface roughness, or any other statistical mean surface roughness of the metal layer.
Consequently, polishing the metal layer may include producing a mean surface roughness less than the mean surface roughness obtained during the deposition of the metal layer. For example, in some embodiments, polishing the metal layer may include producing a mean surface roughness of less than approximately 80 angstroms. In other embodiments, polishing the metal layer may include producing a mean surface roughness of less than approximately 10 angstroms. In yet other embodiments, polishing the metal layer may include producing a mean surface roughness between approximately 2 angstroms and approximately 3 angstroms.
Accordingly, a semiconductor topography having a metal layer with a mean surface roughness less than the mean surface roughness obtained during the deposition of the metal layer may be obtained. For example, a semiconductor topography with a metal layer having a mean surface roughness of less than approximately 80 angstroms may be obtained. In some embodiments, the metal layer may include a mean surface roughness of less than approximately 10 angstroms. More specifically, in some embodiments the metal layer may include a mean surface roughness between approximately 2 angstroms and approximately 3 angstroms. In some embodiments, the metal layer may be arranged within a magnetic random access memory (MRAM device. In such an embodiment, the metal layer may include a digit line of the MRAM device. Alternatively, the metal layer may include a layer within a magnetic tunneling junction of the MRAM device. In yet another embodiment, the metal layer may be arranged within a semiconductor topography that does not include a MRAM device.
In another embodiment of the semiconductor topography described herein, a layer within a semiconductor topography may include a metal surface having a plurality of peaks and valleys associated with the roughness of the metal surface and a fill material arranged within the valleys. In some cases, the fill material may be arranged upon the metal surface such that an upper surface of the fill material is substantially level with at least one of the peaks. In some embodiments, the fill material may include a dielectric; while in other embodiments, the fill material may include a conductive material. As in the embodiments described above, the metal surface may include any metallic material, such as, but not limited to, aluminum, copper, tantalum, tungsten, titanium, or a metal alloy thereof. In addition or alternatively, the metal surface may include a metal nitride, such as, but not limited to, titanium nitride or tungsten nitride. In this manner, the semiconductor layer may include one or more other metal surfaces adapted for electrical connection with a conductive layer. For example, in some cases, the one or more other metal surfaces may include the lowermost surface of the semiconductor structure and/or one or more sidewalls of the semiconductor structure. In addition, the metal surface may be arranged within a MRAM device. In such an embodiment, the metal surface may include a digit line of the MRAM device. In yet other embodiments, the metal surface may include a layer within a magnetic tunneling junction of the MRAM device. Alternatively, the metal layer may be arranged within a semiconductor topography that does not include a MRAM device.
A method for processing a semiconductor topography with such a fill material may include, for example, depositing a fill layer upon a metal layer of the semiconductor topography and polishing the fill layer to form a surface. In some cases, the surface may include portions of the metal layer and portions of the fill layer residing above the metal layer. In such an embodiment, polishing may include removing less than approximately 100 angstroms of the metal layer. In other embodiments, the surface may include the fill layer arranged above an upper boundary of the metal layer-fill layer interface. In general, the interface may include laterally adjacent portions of a metal layer and a fill layer. The upper boundary of such an interface may be denoted by the upper most portion of the metal layer and laterally adjacent portions of the fill layer, while the lower boundary of the interface may be denoted by the lower most portion of the fill layer and laterally adjacent portions of the metal layer. In such an embodiment, in some cases the thickness of the fill layer arranged above the upper boundary may be less than the thickness of the interface. For example, in some embodiments the thickness of the interface may be at least approximately 70 angstroms and the thickness of the fill layer above the interface may be less than approximately 40 angstroms. However, larger or smaller thicknesses of the interface and fill layer above the interface may be appropriate depending on the design specifications of the device.
In either case, polishing the fill layer may include producing a mean surface roughness that is at least approximately 10 times less than a mean surface roughness of the metal layer prior to depositing the fill layer. In this manner, depositing and polishing the fill layer may include producing a mean surface roughness of less than approximately 10 angstroms, for example. In yet other embodiments, the method may include producing a mean surface roughness of less than approximately 4 angstroms, or more specifically between approximately 2 angstroms and approximately 4 angstroms. In some embodiments, the method may include measuring a mean surface roughness of the surface subsequent to polishing. In particular, measuring the mean surface roughness may include calculating an average surface roughness, a root mean square surface roughness, or any other statistical mean surface roughness of the metal layer. In cases when the measured mean surface roughness is above a predetermined value, the method may include re-polishing the surface. In this manner, a lower mean surface roughness may be obtained. In addition or alternatively, the method may include patterning the metal layer. In some cases, the patterning process may be conducted prior to polishing the fill layer. In other cases, the patterning process may be conducted subsequent to polishing the fill layer.
There may be several advantages for reducing the mean surface roughness of a metal layer as described herein. For example, metal layers with substantially smooth surfaces may allow a junction within a MRAM device formed therefrom to breakdown at a higher voltage than in an embodiment in which the junction is formed from layers with relatively rough surfaces. In particular, a MRAM device with substantially smooth layers below a tunneling layer of a magnetic tunneling junction (MTJ) may allow a substantially even and smooth tunneling layer to be formed, thereby preventing the junction from breakdown at a lower voltage. Consequently, the process window at which a MRAM device may be operated may be made larger by the inclusion of substantially smooth surfaces. As a result, the device may be operated at a lower current and consume less power. In addition or alternatively, the reliability and endurance of a device may be increased by the inclusion of smooth surfaces within the device. Furthermore, producing a substantially smooth metal layer may aid in producing substantially smooth layers above the metal layer, since the overlying layers will not conform to a relatively rough surface. Moreover, in the embodiment in which a fill layer is used to fill the valleys of the metal layer associated with the surface, roughness of the metal layer, the method may reduce or eliminate the removal of the metal layer. In such an embodiment, the metal layer may be deposited within the design specifications of the device.

Smooth metal semiconductor surface and method for making the same


An internal liquid for a reference electrode containing lithium chloride (LiCl) and ammonium nitrate (NH.sub.4 NO.sub.3) in a dissolved state at a ratio [NH.sub.4 NO.sub.3 ]/[LiCl].gtoreq. 4. Internal liquid also contains AgCl to saturation for use with an Ag--AgCl internal electrode, and is in a gellated state or impregnated in a highly water-absorbent synthetic resin. It is used in conjunction with a comparison electrode or an internal reference electrode for an ion-selective electrode.. Drying up of the internal liquid in the gellated state is minimized so that the function of the internal liquid as a liquid bridge may be displayed for a prolonged period of time. If the ionic concentration of the liquid under examination is changed, liquid potential difference remains substantially unchanged to provide a stable reference electrical potential.

1. Field of the Invention
This invention relates to an electrode which will give a reference electrical potential for a system for potentiometrically measuring an ion concentration in a solution. More particularly, it relates to an electrode which may be used as a reference (control) electrode or as an internal reference electrode of an ion electrode (ion-selective electrode). The ion electrode includes, for example, a glass electrode used for pH measurements.
In the present specification, the reference (control) electrode and the internal reference electrode of the ion electrode are termed collectively as the "reference electrode".
2. Related Art and Discussion Thereof
As a reference (control) electrode, a silver-silver chloride electrode is used extensively. A potassium chloride solution, saturated with silver chloride, is usually employed as an internal liquid, in which a silver-silver chloride internal electrode is immersed. Occasionally, the internal liquid is communicated with a liquid under examination by means of a salt bridge solution (refer to page 45 of "Ion Denkyoku to Kouso Denkyoku" (Ion Electrode and Enzymatic Electrode) by Shuichi Suzuki).
However, if the internal liquid is present in the state of solution, it may be depleted due to drying or the like. Thus it becomes necessary to replenish the internal liquid for prolonged use. Although it has been attempted to gellate the internal liquid, the gel is similarly deprived of moisture due to drying on prolonged storage so that it no longer acts as a liquid bridge. Therefore, there is much to be required in the conventional reference electrodes.


A power control apparatus according to the present disclosure includes a first interconnection relay and a second interconnection relay configured to interconnect or parallel off an inverter to or from a power grid, a reference potential relay configured to set a neutral phase of an independent operation output system to a reference potential, voltage sensors respectively installed between the first interconnection relay and the inverter and between the first interconnection relay and the power grid, voltage sensors respectively installed between the second interconnection relay and the inverter and between the second interconnection relay and the power grid, and a controller configured to turn the reference potential relay on to set the neutral phase to the reference potential and then to judge whether a state of each interconnection relay is normal on the basis of voltage values measured by the voltage sensors.

A known power control apparatus for a power generation system provided with power generation equipment, such as a solar panel, is capable of grid interconnected operation and independent operation. During grid interconnected operation, alternating current (AC) power is output while the power generation system is interconnected to a commercial power grid (hereinafter also "power grid"). During independent operation, AC power is output while the power generation system is paralleled off from the power grid.
Like the aforementioned power control apparatus, a known electricity storage power control apparatus for an electricity storage system provided with electricity storage equipment such as a storage cell that is charged by power from the power grid is capable of grid interconnected operation and independent operation.

Power control apparatus, control method for power control apparatus, power control system, and control method for power control system


An image processing apparatus forming an image with color toners used for full color printing and a particular toner is provided. The apparatus comprises a storage storing image data and attribute information indicating an attribute of each pixel in the data; a compression component compressing the information; a change component changing attribute information except particular toner information for forming an image with the particular toner of the attribute information, so that a data amount of the compressed attribute information does not exceed the storage capacity, when a data amount of the compressed attribute information exceeds the storage capacity; a component storing the attribute information changed by the change component into the storage; and a component forming a full color image and a particular toner image by image processing using the attribute information in the storage for the image data in the storage.

1. Field of the Invention
The present invention relates generally to image processing in a printing apparatus and particularly to image processing for automatically carrying out many complicated settings required for realizing a visual effect selection in printing-out using a color toner and a particular toner.
2. Description of the Related Art
Recently, a digital printing technology has surely increased its utility value in the on-demand printing market and the document printing market for small number of volumes. Particularly full color printing using an electrophotographic technology is rapidly obtaining a bigger market because of the advantage thereof over the other printing technology in an aspect such as productivity, printing cost and maintainability. Among the technologies, particularly in addition to the full color printing by the conventional electrophotographic printing using basic four color tonners of CMYBk, a multi-color printing method further using a particular toner is getting attention and obtaining a bigger share in a particular printing market which requires a high on-demand capability and real-time capability. The particular tonner includes, for example, a transparent toner which can absorb irregularity on the surface of printed material to achieve a high gloss, and a light toner which can suppress roughness in a highlighted part. By using the particular toner, it becomes possible to obtain a new added value different from that of the typical digital printing and further widen the digital printing world. On such a background, a color composite machine (hereinafter, MFP) mounting a particular toner is being introduced into the market.
The MFP retains image data and attribute information corresponding to each pixel of the image data in a memory, performs image processing on the image data according to the attribute information, and carries out printing. For mounting the particular toner, the MFP develops print data of the particular toner into a binary drawing pattern and combines the data with the attribute information. The MFP performs the image processing on the image data such as color conversion and screen processing according to the attribute information, generates a drawing pattern of the basic four color toners of CMYBk, and takes out the particular toner drawing pattern combined with the attribute information. Then, the MFP sends the basic four color drawing pattern and the particular toner drawing pattern to a print engine for carrying out printing.
The memory for retaining the image data and the attribute information has predetermined storage capacity limit for each of the image data and the attribute information. Accordingly, the image data is compressed for retention by lossy compression so as to have a data amount smaller than the predetermined storage capacity. Meanwhile, the attribute information is compressed by lossless compression to prevent bit loss and sometimes the attribute information amount exceeds the predetermined capacity. For processing the case of exceeding the predetermined capacity, Japanese Patent Laid-Open No. 2006-086649 proposes a technique which increases a compression rate by masking (replacing by a specific value) each bit of the attribute information and thereby reduces the attribute information amount to that smaller than the predetermined capacity for storing.
However, in the technique of the above patent publication, since the particular toner drawing pattern is combined with the attribute information for retention, there is a problem that the particular toner drawing pattern information is erased and the particular toner printing cannot be carried out when each bit of the attribute information is masked.

Secure printing-out using color toner and particular toner


The invention relates to a lighting device for vehicles, particularly for tractors and trailers, with a housing to which light sources of differing light generating types can be exchangeably fastened in an installed state, wherein the light sources of differing light generating types are assigned at least one optic element for the formation of a light module, which is detachably connectable to a carrier frame of the housing, and which generated a defined light function, and wherein a single lens is placed in front of the light modules of differing light generating types in the installed state and the carrier frame.

From EP 1 627 772 A1, a lighting device for vehicles is known, which allows the replacement of a bulb light source by a light diode light source for the generation of the defined light function. To this end, a housing of the lighting device has a lamp holder, so that on the one hand a base of a bulb and on the other hand electrical contacting means of the LED light source can be used. The lighting device according to the prior art does therefore allow the integration of light sources of different light generating types in one housing, wherein the bulb is designed as a thermal radiation emitter and the light diode as a non-thermal radiation emitter. A disadvantage of the known lighting device is, that not only the light sources have to be replaced, but also all optic elements including a lens covering the opening of the housing.


A computer readable medium having instructions is provided. When executed by a computer system, the instructions direct the computer system to identify a control element used to control a process in a machine automation environment, identify a plurality of variables used by the control element to monitor the process, and translate the plurality of variables to a plurality of aliases according to a translation protocol specific to the control element.

Machine automation environments include many types of processing plants, fabrication facilities, assembly lines, and production operations. Devices in machine automation environments are commonly configured, controlled, or monitored using software and automated control mechanisms. In many cases, the software is implemented in the form of a graphical user interface.
A typical machine automation environment includes various devices such as pumps, drives, motors, starters, robots, sensors, switches, actuators, or other devices, including combinations thereof. Machine controllers, control elements, or controllers of other types are often used to control these devices. Machine controllers often interface with multiple devices and have many inputs and outputs. Variable names are typically assigned to the inputs and outputs such that they can be referenced in the software used to create control logic. The control logic is used by the controller to configure, control, or monitor the devices.


An antenna for elliptically polarized television transmission comprising, an elongated cylindrical waveguide having a multiplicity of slots spaced along the length and around the circumference of the waveguide for radiating horizontally polarized energy; a multiplicity of parasitic radiating dipoles mounted on the outer surface of the waveguide and spaced along the length and around the circumference of the waveguide for radiating vertically polarized energy, each of the dipoles being associated with one of the slots so that the combination of the horizontally and vertically polarized radiation produces elliptically polarized radiation; couplers for coupling electromagnetic energy from the interior of the waveguide to the slots; and a pair of coupling capacitors on opposite sides of each slot and connected to the radiating elements of the associated dipole for coupling electromagnetic energy from the field around the slot into the respective radiating elements.

Antennas comprising slotted cylindrical waveguides have been widely used to transmit television signals. In recent years it has become increasingly popular to transmit television signals with circular polarization, primarily to improve the reception of such signals in congested metropolitan areas. As is well known, a transmitting antenna can produce a circularly polarized wave by radiating separate vertically and horizontally polarized waves having the same amplitude with a 90.degree. phase difference. The combination of the vertically and horizontally polarized Waves produces an elliptically polarized wave, with the degree of ellipticity expressed as the "axial ratio,"which is the ratio of the major axis to the minor axis of the ellipse.

Antenna for transmitting elliptically polarized television signals


Embodiments of the present disclosure are directed to conserving energy of an injection device that includes an energy source, an electronic component configured to be electrically decoupled from the energy source, a priming component configured to generate a trigger, and a mechanism attached to the priming component and configured to perform operations comprising in response to receiving the trigger, electrically coupling the energy source to the electronic component.

The life of an electronically-enabled injection device can be dictated by the life of its energy supply. Some electronically-enabled injection devices can be kept on shelves for years before being used. Current configurations of electronically-enabled injection devices lead to idle drainage of the energy supply, such that, even if the electronically-enabled injection device has not been used, long shelf life can exhaust the life of the energy supply. A low battery condition can lead to no- or malfunction of the device, an incorrect dosage, it can lead to a missed dosage, or it can even make the electronically-enabled injection device unusable by stopping the operation of the electronic components.


A safety deflector for an air hammer, comprising a shield formed having a constricted neck portion, an outwardly flaring base portion, the neck portion of the shield applies to the lower end of an air hammer housing, and may be fastened in place either through its inherent resiliency and snug tightening about the housing, or a fastening band may be tightened in position, to more permanently secure the shield in place. Various slots are provided within the deflector, so as to facilitate its installation and application to the air hammer housing, and in addition, provide clearance for the manipulation of the locking lever provided at proximate the bottom of the hammer housing, to furnish clearance for its manipulation when installing or removing a bit from the air hammer.

This invention relates generally to air hammers, and more specifically pertains to a safety shield for use in conjuction with air hammers or other forms of apparatus for use in crushing and breaking concrete or rock, and which shield prevents damage to the worker by intercepting the upward movement of any dust, broken chisel points, rock or concrete chips during the application and usage of the apparatus.
As is well known in the art, air hammers or jack hammers, as they are commonly known, are used for breaking up of concrete, rock, hard dirt, asphalt, and the like, and during such application and usage, it is quite common that concrete pieces, dust, or even possibly broken parts of the chisel bit, have a tendency to be thrusted upwardly, and on occasion, workers have subtained injury, sometimes severely, from such mishaps. But, even in view of such detrimental and harzardous activity, it is not believed that any effort has been made to include safety means into the application and usage of air hammers, and as result, the shield of this current invention is designed for ready application to the housing portion of such a hammer, either during its initial assembly, or as an after market product, in order to alleviate the incidence of such mishaps and injury.

Safety deflector for air hammer and concrete breaker