In performing a printing operation, upon designating the type of paper by inputting it, a paper type table is searched to determine whether the designated type of paper requires a special printing operation, such as reverse feeding and printing. If the above-mentioned operation is required, an appropriate printing operation command is issued. If the above-mentioned operation is not necessary, a normal printing operation command is issued. A determination is also made of whether the designated type of paper requires a special fixing printing, such as cardboard mode fixing. If the above-mentioned operation is required, an appropriate fixing command is issued. If the above-mentioned operation is not necessary, a normal mode fixing command is issued. An image of print data is then formed and printed.

1. Field of the Invention
The present invention relates to a printing apparatus and a printing method in which a plurality of types of recording media are usable and to a storage medium in which a program code implementing the method is stored. The invention is also concerned with an information processing apparatus that transmits print data to effect a printing operation.
2. Description of the Related Art
A printing apparatus, such as a laser beam printer (hereinafter referred to as an "LBP"), forms a printing system when used in cooperation with an information processing apparatus, such as a computer. In the printing apparatus, when printing paper (hereinafter simply referred to as "paper") is the recording medium, it is normally fed with the upper portion of the paper first.
There are some printing apparatus of the above type in which not only standard paper, but also envelopes or postcards, are usable. To perform a printing operation on an envelope by using some such apparatus, it is necessary to feed the envelope in such a manner that the unsealed end leads the sealed end in the direction of feeding. FIG. 1A is a schematic side view of a known LB P illustrating the feeding direction of an envelope to be printed by using the LBP. FIG. 1A shows an LBP 101, a feeding tray 102 on which paper to be fed is placed, an envelope 103 placed on the feeding tray 102, and a discharging tray 105 to which printed paper is discharged. An arrow 104 indicates the direction in which the envelope 103 placed on the feeding tray 102 is fed to the LBP 101.
FIG. 1B illustrates the envelope 103 shown in FIG. 1A as viewed from the top. The envelope 103 has an unsealed end 106 and a sealed end 107.
However, the following problems are encountered when feeding the envelope 103 in such a manner that the unsealed end 106 is placed forward of the sealed end 107 in relation to a printing mechanism (hereinafter referred to as a "print engine") of a printing apparatus, such as an LBP. The incidence of paper jams, described below, is increased. The unsealed end 106 becomes stuck in one of the elements of the paper feeding mechanism, which hampers correct feeding of the envelope 103, thereby causing the envelope 103 to remain within the print engine. This inconveniences the user, wastes paper, and can lead to breakdown or early deterioration (shortening the life) of the print engine.
In order to solve the above problems, the following technique has been proposed. An envelope is fed in such a manner that the sealed end is located forward of the unsealed end, i.e., the envelope is turned 180 degrees from the known feeding direction, and a bit map image to be printed on the envelope is also turned 180 degrees. Printing processing accompanied by the above-mentioned paper feeding and image turning processing is hereinafter referred to as "reverse feeding and printing processing". With reverse feeding and printing processing, the incidence of jams is reduced because the unsealed end of the envelope, which is more likely to be stuck in an element of the paper feeding mechanism, is oriented backward in the direction of feeding, and the sealed end, which is less likely to be stuck in an element of the paper feeding mechanism, is placed forward in the direction of feeding.
FIG. 2A illustrates the relationship between the orientation of an envelope and a bit map image according to, a technique prior to the advent of the reverse feeding and printing processing technique. The bit map image shown in FIG. 2A has been created for the case in which printing is performed by a printing apparatus (LBP) which feeds the envelope to the print engine from the unsealed end. FIG. 2A shows an envelope 202, a bit map image 201 to be printed on the envelope 202, a feeding direction 207 of the envelope 202 to the printing apparatus, a leading position 203 of the bit map image 201, and a trailing position 204 of the bit map image 201. The bit map image 201 is developed and stored in a memory (not shown) within the printing apparatus. A position 205 on the envelope 202 corresponds to the leading position 203 of the bit map image 201, and a position 206 corresponds to the trailing position 204 of the bit map image 201. The printing apparatus prints a visual image, corresponding to the bit map image 201 in the memory, in such a manner that the positions 203 and 204 of the bit map image 201 match the positions 205 and 206 of the envelope 202, respectively.
FIG. 2B illustrates the relationship between the orientation of an envelope and a bit map image according to the reverse feeding and printing processing technique. The bit map image has been created for the case in which printing is performed by a printing apparatus (LBP) which feeds the envelope to the print engine from the sealed end. FIG. 2B shows an envelope 212, a bit map image 211 to be printed on the envelope 212, a feeding direction 217 of the envelope 212 to the printing apparatus, a leading position 213 of the bit map image 211, and a trailing position 214 of the bit map image 211. The bit map image 211 is exactly the same as the image obtained by turning the counterpart 201 shown in FIG. 2A 180 degrees. A position 215 on the envelope 212 corresponds to the leading position 213 of the bit map image 211, and a position 216 corresponds to the trailing position 214 of the bit map image 211. The printing apparatus prints a visual image, corresponding to the bit map image 211 in the memory, in such a manner that the positions 213 and 214 of the bit map image 211 match the positions 215 and 216 of the envelope 212, respectively. In this manner, the reverse feeding and printing processing is implemented.
Known LBPs have a function by which a user can specify the paper type for use in printing, such as "A4", "B5", and "Envelope Kakugata No. 2" (Japanese standard), and can perform a printing operation in accordance with the specified type of paper. By using this function, the information concerning the designated paper type is converted into paper size information that is stored, together with paper type information, in a printing apparatus or an information processing apparatus. The paper size information is then used for printing processing.
Generally, the printing process used in the LBP is as follows. An electrostatic latent image is formed with a laser beam on a drum coated with a photosensitive material, and a coloring powder (toner), which is charged with a polarity opposite to the latent image, is attached to the drum. The latent image is transferred to a paper. A roller is then pressed against the paper to fix the image on the paper by heat and pressure. However, specific types of paper, such as that used in "Envelope Kakugata No. 2", are thicker than standard printing paper, and envelopes are also double-structured to form a bag-like shape. Accordingly, the energy (or paper feeding rate) which would normally be sufficient to raise the temperature to fix the toner on standard paper does not increase the temperature sufficiently to fix the toner on such an envelope. In a conventional printing system, when using the above type of envelope, the user specifies that cardboard paper is being used in order to increase the heating amount to a level sufficient to fix toner on cardboard (hereinafter referred to as "cardboard mode fixing").
The above type of printing system, however, requires a complicated operation, since the user is required to independently utilize a function of designating the type of paper and a function of performing a specific printing process, such as reverse feeding and printing processing and/or the cardboard mode fixing. More specifically, the user first specifies the type of paper, for example, "Envelope Kakugata No. 2", then designates reverse feeding and printing processing, which requires the setting of the envelope in the direction opposite to that shown in FIGS. 1A and 1B on the feeding tray of the printing apparatus, and finally specifies cardboard mode fixing. If the above operations are erroneously performed or the orientation of paper is incorrectly set, printing cannot be performed correctly because the feeding direction has been wrongly set or an image has been insufficiently fixed, thereby wasting time and paper, or causing a breakdown or early deterioration (shortening the life) of the print engine due to paper jams.

Printer control based on detection of envelope-sized print medium


A heat conducting apparatus includes an air guide hood and a heat conducting device. The air guide hood is connected to a hot air supply source for delivering hot air, and includes an air outlet for exit of the hot air. The heat conducting device is disposed at the air outlet of the air guide hood, and includes a contact wall spaced apart from and disposed below the air outlet for contacting a soldered component, and a surrounding wall extending upwardly from the contact wall and connected to the air guide hood. The contact wall and the surrounding wall cooperatively define a space for guiding the hot air. The contact wall conducts the heat to the soldered component so as to melt tin solders between the soldered component and a circuit board, thereby reducing any adverse effect on other electronic components or good chips on the circuit board.

1. Field of the Invention
The invention relates to a heat conducting apparatus and a solder melting method, more particularly to a heat conducting apparatus for heating and melting solders between a soldered component and a circuit board through heat conduction or flow guiding, and a solder melting method for the apparatus.
2. Description of the Related Art
Referring to FIGS. 1 and 2, a circuit board 11 of a handheld electronic device (not shown), such as a mobile phone, a personal digital assistant, etc., generally has ball grid array (BGA) chips 12 soldered thereon. In order to conduct a rework operation on a chip 12′ to be repaired, a conventional rework machine (not shown) employs a hot air convection method to heat and melt solder balls 121 disposed between the chip 12′ and the circuit board 11, so that the chip 12′ can be removed for subsequent repair or replacement.
Since the circuit board 11 of the handheld electronic device has metal shells 13 soldered thereto to cover the chips 12, 12′ for shielding electromagnetic waves, the rework machine needs to melt solder pastes 131 disposed between the corresponding metal shell 13 and the circuit board 11 using the hot air convection method, so that the corresponding metal shell 13 can be removed to allow the subsequent rework operation on the chip 12′ to be repaired to proceed. However, during the process of causing hot air flowing out of an air outlet 141 of an air guide device 14 of the rework machine to heat the corresponding metal shell 13, the hot air may be blocked by the metal shell 13 or the circuit board 11 and change direction, so that electronic components 151 around the metal shell 13 and solder pastes 152 on the electronic components 151 may be heated by the hot air and become melted. Furthermore, some of the hot air may flow into the interior of the metal shell 13 via air vents 132 in a top end of the metal shell 13, which may lead to melting of the solder balls 121 of the chips 12, 12′ and the solder pastes 131 of the metal shell 13.
Referring to FIG. 3, in order that the convection range of the hot air from the rework machine can match the size of the chip 12′ to be repaired, a current approach is to design air guide devices having different sizes of air outlets for different sizes of chips, so that the air guide device can be replaced with one having a suitably sized air outlet to match the size of the chip 12′ to be repaired, thereby reducing the effect of the hot air on the other electronic components 151 or the good chips 12 during the rework process. However, this approach will increase the design and manufacturing costs of the air guide device considerably, which in turn will increase the cost of rework operations. Furthermore, since the hot air flowing out of the air outlet 141 (see FIG. 1) of the air guide device 14 is set to blow downwardly to the chip 12′, the blowing angle of the hot air is not adjustable. Therefore, the hot air will be blocked by the chip 12′ or the circuit board 11 and change direction, so that the electronic components 151 or the good chips 12 may be heated by the hot air, which may lead to melting of the electronic components 151 and the chips 12 or melting of the solder pastes 152 and the solder balls 121 of the chips 12, thereby resulting in loosening of the electronic components 151 and the chips 12. In more serious cases, the tiny electronic components 151 and the chips 12 may be blown away by the hot air and be lost, thereby lowering the rework quality.

Heat conducting apparatus and solder melting method therefor


A MEMS switch according to one aspect of the present invention comprises: a substrate; a fixing portion formed on the substrate; a movable beam including a lower electrode, a first insulation layer formed on the lower electrode, and an upper electrode formed on the first insulation layer, the movable beam having one end fixed by the fixing portion, the lower electrode and the first insulation layer having an opening going through both of the lower electrode and the first insulation layer; a fixed electrode formed on the substrate facing to a bottom surface of the other end of the movable beam, the fixed electrode facing to the opening; a contact electrode formed in the opening so as to project below the bottom surface of the movable beam and to be electrically connected to the upper electrode as well as to be insulated from the lower electrode; and a second insulation layer formed on the fixed electrode and having an opening facing to the contact electrode so as to insulate the lower electrode from the fixed electrode and to permit the contact electrode to come into contact with the fixed electrode.

1. Field of the Invention
The present invention relates to a MEMS (Micro-Electro-Mechanical System) switch that can be applied also as a high frequency circuit switch.
2. Related Background Art
It is desired to apply MEMS, to which a semiconductor process is applied, to various fields. In, for example, a field to which a high frequency circuit is applied, application of MEMS acting as an RF switch is strongly desired.
A MEMS switch applied to high frequency circuit can be used for from direct current (DC) circuit to high frequency circuit and is roughly divided into a DC contact type MEMS switch for supplying power by ohmic contact of two contact points and a capacitive type MEMS switch in which two contact points come into contact with each other through a dielectric film and which can be mainly used only for high frequency of 10 GHz or more.
Since consumer wireless equipment mainly uses a frequency range from about 500 MHz to 5 GHz, the DC contact type MEMS switch in particular has a high value of usage.
An electrostatic drive mechanism is mainly used as a drive mechanism of a conventional DC contact type MEMS switch. This is because a material and a structure are simple and a process is easy.
A typical structure of the MEMS switch is such that a pull-down electrode covered with a dielectric film and an ohmic contact electrode are separately formed in adjacent regions on a substrate as well as a conductive movable beam, which is supported by the base of one side end, is installed so that the other side end thereof is located above the pull-down electrode and the contact electrode. The movable beam has a small spring.
In operation of the MEMS switch, it is opened and closed in such a manner that a voltage is applied between the pull-down electrode and the movable beam, the movable beam is attracted by electrostatic force, and the contact electrode located adjacent to the pull-down electrode is caused to come into ohmic contact with the movable beam.
In the above structure, when an about 10 μm thick movable beam formed by a bulk micro machining method is used, since the movable beam has approximately sufficient rigidity, it is possible to obtain a sufficient amount of press force of the movable beam to the contact electrode.
However, when the movable beam is formed by the bulk micro machining method, a problem arises in that the manufacturing process of the movable beam is made complex and a manufacturing cost becomes expensive.
In contrast, when the movable beam is formed by laminating thin films by a surface micro machining method, manufacturing steps is relatively simple. However, since the thickness of the movable beam is several microns at the maximum and ordinarily 1 to 2 μm and the movable beam is liable to flex due to its small rigidity, it is difficult for the movable beam to apply a sufficient amount of contact pressure to the contact electrode.
Although the bulk micro machining method and the surface micro machining method have advantages and disadvantages, respectively, as described above, it is desirable to employ the surface micro machining method from the view point of suppressing manufacturing cost.
Accordingly, there have been proposed structures for obtaining a sufficient amount of contact pressure force between a contact electrode and a movable beam while employing the surface micro machining method. Refer to, for example, a reference "Inline Capacitive and DC-Contact MEMS Shunt Switches", Jeremy B. Muldavin and Gabriel M. Rebeiz, IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS, VOL. 11, No. 8, pp. 334-386, AUGUST 2001.
The MEMS switch disclosed in the reference has a structure in which a lattice-like contact electrode is formed on a pull-down electrode, and when a voltage is applied between the pull-down electrode, which is exposed to the opening of the lattice-like contact electrode, and a conductive movable beam, the movable beam is attracted and caused to come into ohmic contact with the lattice-like contact electrode.
In the MEMS switch of the reference, however, since the lattice-like contact electrode is formed on the pull-down electrode, the distance between the pull-down electrode and the movable beam must be set in consideration of the thickness of the contact electrode, and it is almost impossible to adjust the distance. Since the distance between the pull-down electrode and the movable beam is increased by the thickness of the contact electrode, the attraction force between the pull-down electrode and the movable beam is still insufficient, and thus the contact pressure force obtained between the movable beam and the contact electrode cannot be sufficient.
To obtain a larger amount of attraction force between the pull-down electrode and the movable beam, it is necessary to increase the exposed area of the pull-down electrode, that is, to reduce the sizes of the respective portions of the lattice-like contact electrode. However, a problem arises from the arrangement in that the contact resistance between the movable beam and the pull-down electrode is increased.
Further, when it intended to obtain a sufficient amount of attraction force by increasing the voltage applied between the pull-down electrode and the movable beam, another problem arises in that power consumption is increased.
From what has been described above, there is required a MEMS switch having such a structure that even if a movable beam is formed of a deposited thin-film, a sufficient amount of contact pressure force can be obtained between the movable beam and a contact electrode as well as the contact resistance between them can be suppressed small.


The present invention is directed toward a method of cleaning an ink jet cartridge assembly and an apparatus for use in such method. The method broadly includes the preparation of ink jet cartridges for vacuum impregnation of heated cleaning solvent and use of centrifugal force to void the cartridge of solvent, ink residue and other waste sediment. During the vacuum impregnation sub-process the heated solvent boils at a lower temperature where internal agitation and turbulence inside the otherwise sealed ink jet cartridge housing causing dried ink and other residue in the ink reservoir foam pads, internal ink paths and print head assembly to return to liquid state and be discharged upon centrifugation. The invention also comprises apparatus to perform vacuum impregnation at proper pressure, spin plates to secure ink jet cartridge housing without damaging ink reservoir foam pads as pin block their discharge and optimum revolution speed can be monitored.

Ink jet recording assemblies have been used for decades to record indicia on a recording medium, such as paper. A typical ink jet recording assembly broadly includes a printer unit and an ink jet cartridge assembly operatively coupled with the printer unit. The cartridge assembly contain a quantity of ink for printing the indicia. In use, the printer unit receives a piece of paper and causes the cartridge assembly to move transversely across the paper between an extended position and a retracted, parked position to print ink on the paper in the form of indicia.
Ink jet cartridge assemblies commonly include a body having an ink reservoir and a head assembly. The head assembly includes an integrated circuit heater, a plurality of ink cups, and a plurality of nozzle openings formed through a nozzle plate. The nozzle openings are positioned beneath the ink cups for printing indicia.
Ink jet print cartridges assembly manufactured by various manufacturers includes a nozzle plate having numerous nozzle openings and additional air openings. The bleed air openings permit ink to be drawn into the head assembly and to the ink cups during use. The ink cups are configured to retain the ink by surface tension to prevent leakage of the ink through the nozzle openings.
The integrated circuit heater includes resistors positioned within the ink cups. The resistors are coupled with a source of electric energy and are kept at an EMF of 24 VDC. The ink cups retain the ink by surface tension until the source of electric energy causes the EMF to drop to about 12 VDC, which then causes the current to increase, heating the resistors. As the resistors are heated, the ink in the ink cups boils and is ejected through the nozzle openings for printing the indicia. The individual resistors may be selectively heated thousands of times per second for relatively precise ejection of ink resulting in relatively precise printing of indicia.
The process of heating and boiling the ink causes sediments and other material to become deposited in and around the nozzle openings and ink cups. As a result, the nozzle openings and ink cups eventually become sufficiently clogged so that the cartridge assembly is unusable. Dried ink is also deposited in and around the nozzle openings, clogging the openings.
Ink jet cartridge assemblies also utilize ink reservoirs to hold ink in an air tight chamber until being drawn into the print head assemblies. When ink is used and no further ink can be drawn to the print head assemblies ink residues remain in ink reservoirs which become sediment.
While several devices and methods are known to remove ink sediments and other debris from print head nozzle openings there appears to be a void related to cleaning the inside of sealed ink jet cartridge assemblies as well as ink paths and print head nozzle openings.
Several devices are known which inhibit the clogging of the nozzle openings. For example, it is known to provide a head washing device mounted on a printer unit for spraying water on the nozzle plate when the cartridge assembly is in the retraced, parked position. By washing the nozzle plate after each use, sediments and other deposited material are moved from the nozzle openings, increasing the operational life of the cartridge assembly. A cleaning solution has also been used to clean a nozzle plate when the cartridge assembly is in the parked position. This does not effect the inside aspects of the cartridge, including the ink reservoir foam pads.
Another known method and device which is known uses a source of steam. Exposing the print head nozzle openings to direct steam is claimed to soften sediments and other materials so they may be removed. On many cartridges, heat in excess of 160 degrees Fahrenheit will soften and damage the adhesive holding the nozzle plate to the print head assembly, thus rendering it useless. Again, this does not effect the inside aspects of the cartridge including the ink reservoir foam pads.
Another known method of cleaning a nozzle plate involves the use of gas such as air or nitrogen gas. Such gas is directed tangentially to the face of the nozzle plate once the cartridge assembly has returned to the parked position. The gas carries sediments and other deposited material away from the nozzle plate, thus increasing the operational life of the cartridge assembly. This does not effect the inside aspects of the cartridge including the ink reservoir foam pads and may disrupt delicate electronic assembly unites if sediment has hardened to them.
It is also known to provide a print head wiper positioned adjacent to the parked position of the cartridge assembly. As the cartridge assembly is returned to the parked position, the wiper removes sediment and other deposited material from the nozzle plate.
Once a cartridge assembly has reached the end of its operational life, either due to clogging of the nozzle openings or emptying of the ink reservoir, the cartridge assembly is removed from the printer unit and replaced by a fresh cartridge assembly. The spent cartridge assembly may then be returned to the manufacturer for recycling.
In a typical recycling process, the ink reservoir is emptied of any remaining ink, and the assembly is cleaned. Even when a cartridge assembly is used in conjunction with a head washing or cleaning device, some amount of sediment and other material will be deposited and hardened in and around the internal ink reservoir including foam pads, internal ink paths and the print head assembly during the operation of the cartridge assembly. Therefore, in a thorough recycling process, the internal ink reservoir including foam pads, internal ink paths and the print head assembly are to remove dried ink and other residue to permit fully operational cartridges following recycling.
Another method of cleaning cartridge assemblies includes the steps of positioning the nozzle plate in a cleaning solution for a short period of time, and wiping the plate to remove the sediments and other material. Once the nozzle plate is cleaned, the cartridge assembly is dried, refilled with ink and tested. Cartridge assemblies which do not meet certain predetermined standards of printing quality are discarded.
Although the cleaning methods available causes some of the sediments and other material deposited in and around the nozzle openings to be removed, many nozzle openings and ink cups remain sufficiently clogged so that the cartridge assemblies must be discarded. As a result, there is a significant and heretofore unsolved need to provide an improved method and apparatus of cleaning not only the nozzle plate of an ink jet cartridge assembly, but also the internal aspects of a cartridge assembly to remove sediments and other material deposited in and around the cartridge assembly which if not already at the nozzle openings, may later flow and xe2x80x9cclotxe2x80x9d the same and diminish or destroy cartridge performance.
The present invention addresses the prior art problems noted above and provides significant advance in the state of the art of cleaning ink jet cartridge ink reservoir tank and foam pads, internal ink paths and print head including the nozzle plate assemblies. The present invention includes an improved method of cleaning an ink jet cartridge assembly and an apparatus for use in such a method.
The inventive method broadly combines the steps of preparing cartridges for optimum cleaning, using a simple vacuum chamber to fully impregnate a cartridge ink reservoir, including the foam pads therein, with cleaning solvent. Lowing the atmospheric pressure of heated solvent causes low temperature boiling action which internally agitates dried ink and other residue in ink reservoir foam pads, internal ink paths and the print head including nozzle plate assembly. Solution warmed at optimum temperature which fully impregnates otherwise sealed cartridge interior will also speed the return of dried ink and other residue to a liquid state for discharge.
Cartridges fully impregnated with solvent and ink residue and other sediments may be voided by centrifugal force without otherwise physically manipulating the sensitive and delicate cartridge components such as the ink reservoir foam pads and the print head including the nozzle plate assembly.
The invention also comprises an apparatus to uniquely permit the stated method to be accomplished optimally.

Ink jet cleaning method and apparatus utilizing vacuum impregnation and centrifuge


A device for transmitting acoustically toward the bottom of the sea includes an arrangement of a cable 404 containing vertically suspended electro-acoustic transducers 403 wherein each of said transducers are assigned to a frequency of the pulse spectrum to be emitted. The transducers are attached to the cable at such positions whereby the wave transmitted toward the sea floor is in phase with the reflective wave on the surface of the sea The superimposition of different elementary signals constitutes a single strong pulse. The device replaces air gun devices for oil exploration.

1. Field of the Invention
This invention pertains to acoustic transmitting antennas which allow one to transmit within the sea acoustic signals which can penetrate into the undersea depths in order to determine the structure of this site, in particular to detect the possible presence of oil.
2. Dicussion of the Background
At present, exploration for oil at sea is conducted by immersing at shallow depth one or several acoustic sources and by using towed linear acoustic antennas which are dragged along behind a ship. These linear acoustic antennas are essentially made of a hollow cable in which hydrophones arranged along the length of this cable are enclosed. The towing ship drags these antennas at relatively slow speed, on the order of 5 knots, in order to accurately gather the signals.
The acoustic signals corresponding to the sources are directed toward the ocean bottom, to the interior of which they penetrate. They are then reflected, as in land exploration, by layers of the subsoil, then they enter the water again and are detected by the hydrophones of the acoustic linear antennas. The bottom of the sea behaves as an additional interface with respect to the interfaces between the different layers of the subsoil. The additional interface simply has more pronounced characteristics than the others, an obviously greater impedance discontinuity in particular.
Because of this considerable change of impedance, it is essentially the low frequency components of the shock wave which effectively penetrate into the undersea depths, however with relatively low efficiency. This phenomenon is identical during the recrossing of the waves between the ocean bottom and the water before reaching the hydrophones.
The overall efficiency thus being relatively low, one must use very powerful acoustic sources.
To date, the only sources which provide satisfaction are devices known by the name of air guns. These devices are not very satisfactory because they are heavy and cumbersome, and they require a compressed air power source from the towing ship.
In addition, the shock wave caused by operation of such a device propagates almost omnidirectionally. The result is that only the weak portion directed toward the sea floor is useful. In addition, the part directed toward the surface is reflected toward the latter and disturbs the useful portion of the impulse.
In order to overcome these disadvantages, different systems have been proposed. In particular, a U.S. Pat. No. 4,632,213 issued on Dec. 30, 1986 in the name of Samuel N. Domenico proposes that one enclose the air gun in a series of concentric tubes which will form the envelope of a paraboloid. These tubes are equipped with perforations through which one can inject the air. The mixture of water and air forms a reflecting discontinuity which has the shape of the paraboloid which encloses the tubes. One can thereby obtain the effect of a reflecting mirror which concentrates on the bottom of the sea the emitted shock wave. However, this device is quite complicated, which further aggravates the difficulties of its implementation. It has been determined in particular that this patent envisages only its use at a fixed station from a drilling platform. Indeed, if one anticipates towing such a device behind a ship, as is frequently the case for air guns used in the traditional manner, one will experience not only great difficulties of implementation, but the relative movement of the water with respect to the device will begin to considerably disturb the shape of the emulsified layer which forms the reflector, which would seriously harm the performance of the unit.

Acoustic transmitting antenna for underwater seismic prospecting


A memory device and a method for fabricating the same are provided. The memory device includes a substrate, a ground layer disposed on the substrate, a stacking structure having a plurality of conductive layers and a plurality of insulating layers alternatively stacked on the ground layer and a plurality of memory strings penetrating through the stacking structure. The ground layer includes a metal layer. The memory strings electrically contact with the metal layer.

Technical Field
The disclosure in generally relates to a semiconductor structure and method for fabricating the same, and more particularly to a memory device and method for fabricating the same.
Description of the Related Art
Recently, there is an increasing need for the more excellent memory device, and various types of the three-dimensional (3D) memory devices are provided, such as a surrounding-gate vertical-channel (SGVC) 3D NAND memory device having a multi-layer structure. This type of the 3D memory device can achieve higher storage capacity and has more excellent electrical characteristics, for example, having better data retention reliability and higher operating speed.
The typical SGVC 3D NAND memory device includes a plurality of stacking structures having a plurality of insulating layers and a plurality of conducting layers alternatively stacked on a substrate, and a plurality of memory layers and a plurality of channel layers longitudinally penetrating through the stacking structures. The intersections of each of the channel layers and each of the memory layers define the NAND memory cells. The NAND memory cells are connected by the channel layers to form NAND memory strings. The NAND memory strings electrically contact with the ground layer under the stacking structure through the ground selecting line (GSL) transistor.
Since the conventional ground layer is formed of the poly-silicon material, the resistance is relatively higher, and it is easy to produce the IR drop effect. To improve this drawback, metal contact structures are generally disposed between the memory blocks longitudinally penetrating through the stacking structure, to guide the current to the ground. However, the arrangement of the metal contact structures compresses the layout space of the memory strings, and further reduces the storage space of the SGVC 3D NAND memory device.
Therefore, there is a need of providing an improved memory device and method for fabricating the same to obviate the drawbacks encountered from the prior art.

Memory device comprising memory strings penetrating through a stacking structure and electrically contacting with a metal layer and method for fabricating the same


A mold rotator with a first section and a second section that are engaged approximately perpendicularly to each other to produce a base and an L-shaped platform for receiving the article. The base of the article rotator may have a curved section at the intersection of the first section and the second section and the article rotator may rotate on its curved section between a first position wherein the article rotator is supported on its first section and a second position wherein the article rotator is supported on its second section. Further, the article rotator allows an article to be safely rotated simply by lowering the article onto the article rotator so that the article rotator automatically rotates approximately 90° from a first position and a second, rotated position. The article rotator may include a stabilizing system.

A mold is tooling that is used to produce parts in a molding process such as injection molding, die casting or other similar technologies. For example, in an injection molding process, a mold may include at least two sections that when engaged together form the mold. While plastic injection molds can have at least two movable sections, alternatively they may be comprised of several movable sections. The interior of the mold has one or more cavities. The cavities have a particular design that is the inverse of the part or parts to be manufactured. In the injection molding process, molten plastic is inserted into the cavities and the part or parts are formed in the cavities upon solidification of the plastic. When the formation of the part or parts is complete, the mold is opened to remove the part or parts.
Molds can vary greatly in size and weight depending on several factors. One such factor is the material from which the mold is created. For example, conventional molds may be constructed from steel, aluminum or other materials. Further, the size and weight of the mold will depend on the part or parts that will be manufactured in the molds. For example, molds can be used to produce small plastic components or extremely large items such as boat hulls. For larger items, the size and weight of the mold can range up to 60 tons or more.
At times it may be necessary to rotate a mold for inspection, disassembly, cleaning, repair, etc. Due to the size and weight of a mold, mold rotators (also called "mold tippers") may be used to rotate the molds. One advantage of rotating the mold is that the rotated orientation of mold may be much more conducive for disassembly of the mold or removal of the mold from the mold rotator. For example, if a mold is comprised of several sections, the orientation of the mold in the rotated position may allow for the mold sections to be separated much more safely and easily than when the mold is the non-rotated orientation.
Some conventional mold rotators may include hydraulic systems and/or motorized systems to rotate a mold. These conventional mold rotators may include gear systems, roller guides, etc. Such mold rotators are expensive, complicated and cumbersome.
Other conventional mold rotators may not have such complicated systems, however, these simpler conventional mold rotators suffer from the drawback that once the mold rotator has been rotated, the mold cannot be easily and safely removed from the mold rotator. In other words, in such a mold rotator, if the mold is inserted into the mold rotator and then rotated from that first position to a second, rotated position, then the mold cannot be easily and safely removed from the mold rotator, because the mold rotator will self-rotate back to the first position upon removal of the mold. Further, the mold cannot be disassembled while in the more conducive rotated position, because if the weight of the partially disassembled mold becomes too light, the mold rotator will self-rotate back to the first position. This inadvertent rotation of the mold rotator from the rotated position back to the first position can be dangerous to the operator of the mold rotator and also hazardous for both the mold rotator and the mold itself. These simple conventional mold rotators lack a stabilizing system to hold the mold rotator stationary in a rotated position so that the mold can be disassembled or removed from the mold rotator while the mold is in the rotated position which is more conducive to removal or disassembly.
Accordingly, it would be advantageous to provide an inexpensive and simple mold rotator that will allow a mold to be safely rotated and stabilized in either of a first position or a second, rotated position.

Method of rotating mold or other articles


The present invention is directed to a device and methods for immobilizing a localized region of a compliant body. A device of the invention includes at least two arms, an elbow region between the arms, and a suction arrangement. During use the region of the compliant material to be immobilized is flanked by the arms and a negative pressure is applied through the suction arrangement to immobilize the flanked region. The device of the invention is suited for use in medical applications, for example, coronary bypass graft surgery.

In general, performing an exacting procedure on a compliant material can be difficult due to the inherent evasive nature of the material. The difficulty can be exacerbated if the compliant material is mobile. One example of an exacting procedure performed on a mobile compliant material is cardiovascular surgery performed on a beating heart. Devices and methods are available for immobilizing the heart during cardiovascular surgery. However, many available systems can have undesirable effects on the patient.
Coronary artery bypass (CABG) surgery is a technique for revascularization of the heart necessitated by coronary artery obstruction. Typically, this procedure is facilitated by reducing or stopping the motion of the heart to allow for accurate suturing of the anastamoses. Present methods for reducing or stopping the motion of the heart include pharmacological and presently available mechanical means. If the heart is stopped, cardiopulmonary bypass (CPB) equipment (heart/lung machines) is used to maintain systemic blood flow. The use of pharmacological agents, with or without CPB equipment, and presently available mechanical methods to restrain the heart have inherent disadvantages.
Pharmacological agents can be used to slow or stop the heart. Usually, these drugs are administered systemically and in the case of cardioplegic agents must have a short duration of action. One disadvantage of pharmacological slowing of the heart is that the heart continues to beat thus allowing only intermittent suturing of anastomoses between beats. In addition, cardiac slowing compromises systemic circulation to vital organs thus limiting broad application of these techniques without cardiac support.
Generally, the use of cardioplegic agents necessitates use of cardiopulmonary bypass (CPB) equipment or heart/lung machines. While complete cardiac arrest allows accurate construction of anastomoses, CPB equipment is expensive to operate and can cause significant pathophysiological effects in the patient. Examples of pathophysiological consequences which can occur with CPB equipment include cardiac consequences, neurological consequences, pulmonary dysfunction, renal dysfunction, hepatic dysfunction, coagulapathies, blood element trauma and impairment of cell-mediated immunity.
Mechanical means to stabilize the heart during cardiac surgery use compression or traction to sufficiently restrain the heart to permit anastomoses of the vessels. Known mechanical devices are disclosed in, for example, U.S. Pat. Nos. 3,983,863, 4,973,300 and 5,509,890. These devices generally stabilize a localized area of the heart by compression. However, compressive forces sufficient to stabilize the heart can functionally deform the pumping chambers of the heart and impair cardiac filling or effective pumping between cardiac contractions. Hence, cardiac output is compromised. In addition, the frictional forces exerted by some devices during restraint can cause tearing or abrasion of the epicardial surface of the heart. Moreover, these devices have a limited range of access thus limiting utility of such devices to situations where only one or at most two adjacent arteries are to be bypassed.
Accordingly, there is a need for devices and methods to stabilize a compliant body during performance of an exacting procedure. In the case of living organs, there is a need to stabilize the organ without significantly compromising normal physiological function and without inducing trauma to the organ or the patient. Moreover, there is a need for devices and methods to perform exacting procedures on living organs without the use of costly patient support systems.

Device for regional immobilization of a compliant body


Disclosed are a key sheet for a pointing device and a pointing device using a magnet compact in terms of both magnetic force and size to allow a reduction in thickness. Between a pusher (14f) opposed to a contact input portion (E) of a board (P) and a magnet (11) fixed to a base sheet (14) at an outside position around the pusher (14f) as a center so as to be away from a key top (15), there is provided an elastic flexible portion (14d) allowing displacement in a depressing direction through depression of the key top (15) toward the contact input portion (E). As a result, it is possible to perform depressing operation on the key top (15), with the magnet (11) being provided on the base sheet (14), making it possible to perform switch input, such as confirmation input.

1. Field of the Invention
The present invention relates to a pointing device utilized as an operating device for an electronic apparatus such as a mobile phone, a PDA, or a game controller, and to a key sheet for the pointing device. In particular, the present invention relates to a magnetic detection type pointing device which detects a change in magnetic flux density resulting from movements of a magnet, and to a key sheet for the pointing device.
2. Description of the Related Art
Nowadays, operating devices of electronic apparatuses and input systems thereof have been diversified. In this context, a magnetic detection type pointing device is known, in which a change in magnetic flux density due to "sidewise movement" of a magnet, such as tilting or horizontal displacement of the magnet, is detected by a magnetic sensor, and in which the change thus detected is utilized as an input signal. This technique is disclosed, for example, in JP 2000-235822 A, JP 2004-62447 A, and JP 2002-150904 A. In those pointing devices, a magnet is integrally accommodated in a key top to be depressed, and is moved through operation of the key top, with the movement amount of the magnet being detected by a magnetic sensor provided on a board.
In such magnetic detection type pointing devices, in which the magnet moves, there is provided some contrivance in terms of arrangement to prevent the magnet and the magnetic sensor from coming into contact with each other. For example, in the pointing devices as disclosed in JP 2000-235822 A and JP 2004-62447 A, the magnetic sensor is mounted on a back surface of the board, and even if the key top moves on the board, it does not come into contact with the magnetic sensor. However, when the magnetic sensor is provided on the back surface of the board, a distance between the magnetic sensor and the magnet is larger than in the case in which the magnetic sensor is provided on a front surface of the board, so it is necessary to use a powerful magnet. Further, it is necessary to provide a mounting space for the magnetic sensor on the back surface of the board, with the result that a thickness of the pointing device becomes rather large.
In contrast, in the technique as disclosed in JP 2002-150904 A, the magnetic sensor is mounted on the front surface of the board, so the distance between the magnetic sensor and the magnet is shorter as compared with the case in which the magnetic sensor is mounted on the back surface of the board. However, the magnet is provided inside the key top for input operation, so it is all the same necessary to use a powerful magnet, and the thickness of the magnet cannot help but be rather large. As a result, peripheral members are adversely affected by a strong magnetic field generated, and the thickness of the key top cannot be reduced due to the thickness of the magnet.

Key sheet for a pointing device and pointing device


A safety barrier is formed of framing, including a guard rail that defines the infill below the rail without the use of pickets. The infill is covered with mesh screen, which may be made of nylon which has greater tensile strength than conventional fiberglass. The mesh screen is held to the framing by an extruded base. The base has a central channel between two flat spline grooves. Flat splines hold mesh screen in their respective grooves more securely than conventional friction-based channel splines. A metal plate is positioned in the central channel to enables screws that secure the base to be tightened to hold it to the framing better. The elimination of pickets in the infill leaves the view unobstructed and allows other treatments of that portion of a deck or porch that are more aesthetically pleasing without compromising safety.

A deck or porch can extend the livable area of a home considerably. Because decking and porches are oftentimes elevated with respect to the surrounding ground, the risk of falling off the deck or porch must be considered. Commonly, a guard rail is constructed at about waist height to prevent falling. However, a child or a seated adult could still fall from the deck despite the guard rail. To prevent this type of injury, pickets, narrow spaced-apart pieces of lumber, are fastened perpendicularly to the guardrail. Even in porches where typical mesh screening is attached below the guard rail, pickets are nonetheless necessary for safety because mesh screening cannot be counted on to prevent someone from falling off the porch or deck. Mesh screening may tear or come loose when subjected to lateral impact.
The area below the guard rail in a porch is referred to as infill. Two typical building code requirements apply to the infill. First, the infill section must be able to prevent a sphere of 10 cm (4 inches) from passing through any part of the infill. Second, when a 125-pound load is applied to a one-square-foot area, from either direction, the infill must not disengage from its framework. Pickets will meet that requirement when placed not more than 4 inches (10 cm) apart. Unfortunately, pickets partially obstruct the view from the deck and are an inconvenience to maintain. They also foreclose any alternate, aesthetic appearance for a deck or porch.
An infill that is safe but avoids the use of pickets would have several useful advantages.


A method and apparatus are provided for isolating a defect in a scan chain comprising a plurality of components of an integrated circuit. A plurality of injection points may be positioned along the scan chain. Each injection point may be configured to introduce binary test data. A plurality of bypass structures may each be configured to selectively direct a flow of the binary test data to generate a plurality of partitioned scan paths. Test logic may be configured to execute a plurality of tests using the plurality of partitioned scan paths and to combine results of the plurality of tests to isolate a faulty component of the plurality of components.

A circuit design may include a plurality of latches, such as shift register latches (SRLs), which are catenated to form a level sensitive scan design (LSSD) scan chain. As a part of quality control, patterns of logic "0" and logic "1" may be shifted into scan chains to observe an output of a scan chain under test. Because the circuitry of the scan chain is wired in series, a fault encountered in the scan chain can obscure downstream determinations as to the functionality of scan chain components. As a result, an entire the logic circuit may be discarded, resulting in waste and inefficiency. Diagnosing failing locations can lead to fabrication process and design changes that improve later yield and reduce this waste.

This patent is subject to a terminal disclaimer.

Partitioned scan chain diagnostics using multiple bypass structures and injection points

INTERNATIONAL BUSINESS MACHINES CORPORATION


Example embodiments may relate to a series elastic actuator (SEA). The SEA may include a motor, a transmission assembly, and an output plate that collectively form a motor housing assembly. The motor housing assembly may be supported on bearings that allow for a rotation of the motor housing assembly. The bearings may be supported on a housing of the SEA that may be connected to a robot link. Springs may be connected between the housing and the transmission assembly. The springs may be connected such that friction is reduced between the balls and races of the bearings. A sensor may be configured to measure a rotary deflection of the transmission assembly. A string may be wrapped around a rotary shaft of the sensor and ends of the string may be attached to the transmission assembly such that a rotation of the transmission assembly causes a rotation of the rotary shaft.

Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Robotic systems may be used for applications involving material handling, welding, assembly, and dispensing, among others. Over time, the manner in which these robotic systems operate is becoming more intelligent, more efficient, and more intuitive. As robotic systems become increasingly prevalent in numerous aspects of modern life, the need for human safe robotic systems becomes apparent. Therefore, a demand in human safe robotics has helped open up a field of innovation in sensing techniques, actuators, as well as component design and assembly.


Methods and apparatuses for processing MR signal are disclosed herein. An exemplary method comprises: when acquired K-space signals are amplified, assigning a first amplification gain to signals within a first signal region in the K space, and assigning a second amplification gain to signals within a second signal region in the K space.

In the MR scanning imaging technology, it is common knowledge in the art to acquire MR signals based on K space. The acquired K-space signals need to be amplified via a radio frequency (RF) preamplifier, and then to be converted, via an analog/digital converting device, into digital signals for image reconstruction. Therefore, when pre-scanning is performed, amplification gains for the K-space signals need to be adjusted such that intensities of the K-space signals can be amplified to an appropriate extent.
Currently, a K-space model called "3D radial" has been applied in MR imaging. Such model is spherical, with intensities of signals in a central region close to the center of the model being far greater than intensities of signals in a region away from the center of the model. Therefore, in order to avoid excessively large amplification gain which might cause a high-intensity signal to be overly amplified to exceed a detection range of the analog/digital converting device, usually a lower amplification gain would be utilized to adapt to those high-intensity signals at the time of determining the amplification gain for the signals. However, when the lower amplification gain is utilized, signal-to-noise ratio (SNR) of the reconstructed image might be lower.
Accordingly, there is a need to provide with a new method and apparatus for processing MR signals, which can improve image quality.

Method and apparatus for processing MR signal, and computer program


A coated member is disclosed. The coated member has a member and a coating disposed on the member. The member is metallic and the member is bent at two or more locations along a length of the member. The coating is an elastomeric coating. The coated member is a soil reinforcing member.

Many construction projects include providing coated metallic elements in locations of varying levels of corrosivity, such as in aggressive and/or non-aggressive soils for corrosion. Metallic elements may be disposed in soils that may cause corrosion over relatively long periods of time, or in soils that may cause corrosion in relatively shorter periods of time such as areas exposed to chemical deicing, tidal water, or ground water. Use of coated metallic elements in either aggressive or non-aggressive soils often results in increased degradation of the coating and base metal of the coated metallic elements over time. Such degradation may result in a reduction of a service life of a structure.
Conventional methods for protecting metallic elements in the above situations typically involve providing metallic elements including steel strips or wires that are galvanized or aluminized. For galvanized coatings, steel strips or wires are typically configured into a final geometry, then hot-dip galvanized in a bath of zinc. For aluminum coatings, a sheet of steel coil is typically dipped in a bath of pure aluminum, and then the steel coil is slit and the steel strips are configured into a final geometry.
One disadvantage of these conventional systems involves the additional metal needed beyond an amount appropriate for strength and serviceability design to account for corrosion of metallic reinforcements within an area subject to corrosion (e.g., within an earth mass as in mechanically stabilized earth applications). For example, typical design specifications for highway infrastructure set forth that a design should account for 75 or 100 years of corrosion, which typically results in an increase in supplied metal thickness of metallic elements of approximately 50% to 100% more than a nominal amount appropriate for strength and serviceability design.
U.S. Pat. No. 8,927,112 (the '112 patent), issued to McKittrick, describes a protective coating for use in a mechanical connection of a mechanically stabilized earth structure. The method disclosed in the '112 patent includes applying a dielectric barrier coating on a structurally compromised region of a tensile member to delay an onset of corrosion.
Although the system disclosed in the '112 patent may provide a method for delaying an onset of corrosion, the system does not provide a method for accounting for corrosion of a coated metallic element over substantially an entire service life of a structure. Further, the system disclosed in the '112 patent does not appear to provide a method for providing relatively thinner metallic elements that account for corrosion over a service life without having increased thicknesses to account for corrosion.
The present disclosure is directed to overcoming one or more of the shortcomings set forth above.

System and method for protective coating of reinforcement


A method is provided of extracting desired signals st from contaminated signals yt measured via respective communication channels. The system comprising the desired signals st and the channels is modelled as a state space model. In the model, the desired signals have time-varying characteristics which vary more quickly than second time-varying characteristics of the channels.

The present invention relates to a method of extracting a signal. Such a method may be used to extract one or more desired signals from one or more contaminated signals received via respective communications channels. Signals may, for example, be contaminated with noise, with delayed versions of themselves in the case of multi-path propagation, with other signals which may or may not also be desired signals, or with combinations of these.
The communication path or paths may take any form, such as via cables, electromagnetic propagation and acoustic propagation. Also, the desired signals may in principle be of any form. One particular application of this method is to a system in which it is desired to extract a sound signal such as speech from contaminating signals such as noise or other sound signals, which are propagated acoustically.
WO 99/66638 discloses a signal separation technique based on state space modelling. A state space model is assumed for the signal mixing process and a further state space model is designed for an unmixing system. There is a suggestion that the communication environment for the signals may be time-varying, but this is not modelled in the disclosed technique.
U.S. Pat. No. 5,870,001 discloses a calibration technique for use in cellular radio systems. This technique is a conventional example of the use of Kalman filters.
U.S. Pat. No. 5,845,208 discloses a technique for estimating received power in a cellular radio system. This technique makes use of state space auto regressive models in which the parameters are fixed and estimated or "known" beforehand.
U.S. Pat. No. 5,581,580 discloses a model based channel estimation algorithm for fading channels in a Rayleigh fading environment. The estimator uses an auto regressive model for time-varying communication channel coefficients.
Kotecha and Djuric, "Sequential Monte Carlo sampling detector for Rayleigh fast-fading channel", Proc. 2000 IEEE Int. Conf. Acoustics Speech and Signal Processing, Vol. 1, pages 61–64 discloses a technique for processing digital or discrete level signals. This technique makes use of modelling the system as a dynamic state space model in which channel estimation and detection of transmitted data are based on a Monte Carlo sampling filter. Channel fading coefficients and transmitted variables are treated as hidden variables and the channel coefficients are modelled as an autoregressive process. Particles of the hidden variables are sequentially generated from an importance sampling density based on past observations. These are propagated and weighted according to the required conditional posterior distribution. The particles and their weights provide an estimate of the hidden variables. This technique is limited to modelling of sources with fixed parameters.
Chin-Wei Lin and Bor-Sen Chen, "State Space Model and Noise Filtering Design in Transmultiplexer Systems", Signal Processing, Vol. 43, No. 1, 1995, pages 65–78 disclose another state space modelling technique applied to communication systems. In a "transmultiplexer" scheme, desired signals are modelled as non-time-varying autoregressive processes with known and fixed parameters.


A sprayable coating agent is disclosed in the form of granules with which the granules are compacted to form a pressed piece, subsequently ground up and optionally sieved, whereby the granules have the following particle-size distribution: 0%-40% by weight: 0-600 microns; 5%-55% by weight: 600-1250 microns; 5%-95% by weight: >1250 microns; or 15% by weight: 0-800 microns; 0%-85% by weight: 800-2000 microns; 0%-15% by weight: >2000 microns. Likewise disclosed are its production, further processing and use for internal and external applications.

German utility models DE 296 21 864 U1 and DE 296 04 493 U1 as well as German preliminary published applications DE 43 17 957 A1 and DE 36 06 167 A1 disclose sprayable coating agents for surface-structured wall or ceiling coverings as alternatives to liquid wood chips or wood-chip wallpaper. This is a material mixture consisting of cellulose fibers with curing agents, binders, colorants and water. Additives made of other cellulosic and inorganic materials are likewise claimed. The surface structure is changed by varying the air pressure during the spraying and by changing the consistency of the compound. According to German utility model DE 296 04 493 U1, a surface structure matching rough plaster is created when the air blisters burst.
Likewise known are dry mixtures based on cellulose fibers that dissolve in water and that can be employed to cover walls and ceilings. Familiar commercial products for covering walls and ceilings are, for example, Naturlan Nature-Floc® on the basis of cotton fibers as well as Faserit on the basis of wood, marble meal, loading materials and vegetable adhesives.
The above-mentioned coating agents and methods, however, only allow the creation of surface structures that are sprayed with a semi-fluid, pasty compound employing a variable supply of compressed air. Since the cellulose breaks down into fine fibers, this structure is fundamentally different from purely grainy structures of the type known from textured plaster (grainy loading materials such as marble meal, sand or silicate). It is difficult and complex to establish and reproduce a uniform surface structure via the air pressure and this can only be done by an experienced specialist. In the case of textured and structured plaster, it is also difficult to apply a uniform grainy structure onto a wall or ceiling. Overhead work is tricky and can only be performed with skilled craftsmanship.

Sprayable coating agent, its production, further processing and use thereof


A lubricating oil composition comprising (A) a base oil containing 3% by weight or less of aromatics, 20% by weight or more of monocyclic naphthenes, 50 ppm by weight or less of N and 50 ppm by weight or less of S, having a viscosity (100.degree. C.) of 2 to 50 mm.sup.2 /s, (B) alkyldiphenylamines and/or phenyl-alpha-naphthylamines in an amount of 0.05 to 2% by weight of the total weight of the composition, and (C) C.sub.8 -C.sub.23 MoDTC and/or C.sub.8 -C.sub.18 MoDTP and/or C.sub.8 -C.sub.18 MoDTX in such an amount that the amount of Mo is 50 to 2000 ppm by weight of the total weight of the composition. The lubricating oil composition has high heat resistance, high oxidation stability and excellent lubricating properties, and is particularly useful for a lubricating oil for internal combustion engines and the like.

1. Field of the Invention
The present invention relates to a novel lubricating oil composition, and more specifically to a lubricating oil composition having high heat resistance, high oxidation stability and excellent lubricating properties, useful as a lubricating oil for internal-combustion engines, automatic transmission gearboxes, dampers, power steering units and the like, particularly useful as a lubricating oil for internal combustion engines.
2. Description of the Related Art
Lubricating oils have been used for internal combustion engines, and for driving units and gears such as automatic transmission gearboxes, dampers and power steering unit in order to smoothly operate them. In particular, lubricating oils for internal-combustion engines (engine oils) not only lubricate various sliding portions such as a piston ring, a cylinder liner, bearings for a crank shaft and a connecting rod, and a valve-operating mechanism including a cam and a valve lifter, but also cool the inside of the engines, clean and disperse those products which are produced by combustion, and prevent the rusting and corrosion of the engines.
Thus, the lubricating oils for internal-combustion engines have been required to have a great variety of properties. Moreover, due to the recent trend toward high-performance, high-output internal-combustion engines and more severe operating conditions, the lubricating oils are required to have higher quality. In order to meet this requirement, various additives such as an antiwear agent, a metallic detergent, a nonash dispersant and an antioxidant are incorporated into the lubricating oils for internal-combustion engines.
It is particularly important as the essential function of the lubricating oils for internal-combustion engines that the lubricating oils can ensure the smooth operation of the engines under every condition to prevent the wear and seizure of the engines. The parts of the engines to be lubricated are, in most cases, under the fluid lubrication condition. However, the valve train, and the top and bottom dead centers of a piston tend to be under the boundary lubrication condition. Antiwear properties under the boundary lubrication condition are generally imparted by the addition of zinc dithiophosphate (ZnDTP) or zinc dithiocarbamate (ZnDTC).
Energy loss at the friction parts of internal-combustion engines which are lubricated by lubricating oils is great. For this reason, a lubricating oil to which various additives including a friction modifier (FM) are added has been used in order to reduce the friction loss and to decrease the fuel cost (e.g., Japanese Laid-Open Patent Publication No. 23595/1991). Lubricating oils for automotive internal-combustion engines are used at various temperatures, at various revolutions per minute and under various loads. Therefore, in order to further improve the rate of fuel consumption, it is necessary that the lubricating oils be excellent in friction properties under a wide range of conditions under which they are used.
Besides the above-described properties, high heat resistance, high oxidation stability and moderate viscosity characteristics can be mentioned as the properties required for the lubricating oils for internal-combustion engines.
The present invention is directed to meeting these requirements. An object of the present invention is therefore to provide a lubricating oil composition having excellent lubricating properties, high heat resistance, high oxidation stability and moderate viscosity characteristics, particularly useful as a lubricating oil for internal-combustion engines.


A timing device for coordinating a presentation includes a master timer with a timing initiator, a programmable master sequencer responsive to the timing initiator, a master sensory alarm responsive to the sequencer, a master alarm silencer, and a communication transmitter responsive to at least one of the timing initiator and the master sequencer. The timing initiator begins operation of the master sequencer. The master sequencer actuates the master sensory alarm at at least one predetermined time after initiation. The communication transmitter sends a signal when the timing initiator beginning operation of the master sequencer or at a predetermined time after initiation of operation of the master sequencer. At least one slave timer, and optionally a plurality of slave timers, is provided. Each slave timer includes a communication receiver responsive to the communication transmitter of the master timer, a slave sensory alarm operatively responsive to the communication receiver, and a slave sensory alarm silencer. The communication receiver receives the signal from the communication transmitter and responds,by operatively activating the slave sensory alarm at the time the signal is received or at a predetermined time after the signal is received.

In many professions there is the need to make oral presentations within defined time limits. For example, an attorney is often required to present an opening argument or a closing argument, or other type of argument, wherein a specific amount of time is allotted for the argument. Another example might be a scientist, engineer or other professional who is presenting a paper to an audience within a specific time frame. A third example is a formal interview presentation given by an individual or group of individuals, wherein information is presented in a formal setting to a body that will be selecting a firm or individuals to perform work.
In each of these situations time constraints may be critical, if not mandatory. Further, it is often desirable to divide a presentation into segments, such as an opening, body, and closing, to provide for a question and answer period, to reserve time for future use, or to divide the presentation time among a plurality of presenters.
Typically, in these presentation settings, the individual or individuals making a presentation are preoccupied with the specific information included in the presentation and can easily loose track of time. In presentations involving several presenters, one presenter exceeding the time limits can greatly affect the portions to be presented by the other presenters, and the quality of the overall presentation.
Prior art timing devices are typically involve a distracting and disruptive audible or visual alarm, or are limited to a single alarm point. Further, prior art timing devices typically require imprecise manual synchronization if they are to used by multiple presenters.

Coordinated presentation apparatus and method


A recording liquid to be attached in a droplet state to an object for the purpose of recording on the object is disclosed, which contains at least one alkylene glycol selected from 1,2-pentanediol, 1,2-hexanediol and 1,3-hexanediol, thereby adjusting a zero second dynamic surface tension thereof at 35 mN/m or more and not more than 40 mN/m and contains a surfactant, thereby adjusting a static surface tension thereof which is satisfied with the following numerical expression (1):(γdst0−3)≦γsst≦(γdst0−1)  (1)wherein γdst0 [mN/m] represents a zero second dynamic surface tension; and γsst [mN/m] represents a static surface tension.

1. Field of the Invention
The invention relates to a recording liquid to be attached in a droplet state to an object for the purpose of recording on the object, to a liquid cartridge having this recording liquid accommodated therein, and to a liquid discharge device and a liquid discharge method of forming the recording liquid accommodated in this liquid cartridge in a droplet state and discharging it onto an object from a discharge nozzle.
2. Description of the Related Art
Examples of a liquid discharge device include a printer device of an inkjet system of discharging an ink of a recording liquid onto recording paper which is an object, thereby printing images or letters. This printer device of an inkjet system has such an advantage that it is easy to attain low running costs, miniaturization of device and colorization of images or letters.
Examples of the inkjet system of discharging an ink include a diffraction system, a cavity system, a thermojet system, a Bubble Jet (registered trademark) system, a thermal inkjet system, a slit jet system, and a spark jet system. In such an inkjet system, an ink is discharged from a discharge aperture, a so-called nozzle, of an ink discharge head for discharging an ink in a state of a fine droplet and impacted on recording paper, thereby printing images or letters.
In the printer device of an inkjet recording system, there may be the case where the printing is carried out on not only dedicated papers for inkjet recording but also plain papers such as copying paper and writing pad. For that reason, an ink used in the inkjet recording system is required such that even in case where the printing is carried out on not only dedicated papers for inkjet recording but also plain papers, it is possible to achieve printing high-grade images or letters which are especially high in image density, free from bleeding of images or letters, concretely bleeding of boundaries between different colors and unevenness of mixed color, etc. and less in strike through of ink. In order to meet these requirements, examples of the ink which is used for the inkjet recording system include ones described in JP-B-60-23793 (Patent Document 1), JP-A-56-57862 (Patent Document 2), JP-A-6-157959 (Patent Document 3), JP-A-2003-3100 (Patent Document 4), JP-A-2003-253167 (Patent Document 5) and JP-A-8-170041 (Patent Document 6).
Patent Document 1 describes that by using a dialkyl sulfosuccinic acid as a surfactant, dryness is improved. However, according to the ink described in this Patent Document 1, not only a pH region of paper where it is expected to improve the dryness is narrow, but also an improving effect with a lapse of time is deteriorated or a print density is low.
Patent Document 2 describes that by adding a strongly basic substance in an ink, bleeding of an image is suppressed. However, according to the ink described in this Patent Document 2, the effect is useful for only acidic papers but is hardly revealed in plain papers of a neutral paper type.
Patent Documents 3 and 4 describe that by containing a specified amount of each of a wetting agent, a surfactant and 2-ethyl-1,3-hexaediol in an ink, image bleeding, especially image bleeding in a superposed color part is improved. However, according to the inks described in these Patent Documents 3 and 4, though the image bleeding can be improved, strike through of the image is large, the image density is low, and a sufficiently satisfactory high-grade image is hardly obtainable.
Patent Document 5 describes that by containing 2,4-diethyl-1,5-pentanediol in an ink, strike through of the ink is suppressed. However, according to the ink described in Patent Document 5, though image bleeding can be improved, likewise the foregoing Patent Documents 3 and 4, strike through of the image is large, the image density is low, and a sufficiently satisfactory high-grade image is hardly obtainable.
Patent Document 6 describes that by containing propylene glycol monopropyl ether, dryness and image bleeding are improved. However, according to the ink described in Patent Document 6, the effects on dryness and image bleeding are low, and a sufficiently satisfactory high-grade image is hardly obtainable, too.
In the printer device of an inkjet recording system, for example, a printer device capable of performing high-speed printing on recording paper, namely a line type printer device in which a range substantially the same as a width of recording paper is the discharge range of the ink, bleeding of images or letters, strike through of an ink and so on are remarkably caused (see, for example, JP-A-2002-36522 (Patent Document 7)).
In the line type printer device, an ink is discharged for every nozzle line in which nozzles for discharging an ink are arranged in parallel in a range substantially the same as the width of recording paper, thereby performing once printing in one line over the width direction of recording paper. Thus, a discharge cycle of the ink in every nozzle line is extremely short. For that reason, in the line type printer device, when permeation of an ink which is discharged one after the other into the recording paper is slow, bleeding of the ink on images or letters or the like is caused.
Then, in the line type printer device, it is necessary to use an ink having excellent penetration properties into recording paper.
However, in the line type printer device, in the case where printing is carried out on plain paper or the like by using an ink having excellent penetration properties, there may be a possibility that the print density becomes low because the ink excessively permeates in a depth direction, namely a thickness direction of the plain paper.
In the line type printer device, when so-called color printing in which inks having a different color from each other are discharged onto recording paper to achieve printing is carried out, even by using an ink having excellent penetration properties, since the discharge cycle of the ink in every nozzle line is extremely short, before the ink impacted on the recording paper sufficiently permeates into the paper, an ink of a next color is impacted one after the other. For that reason, in the line type printer device, there may be a possibility that bleeding of boundaries between the respective colors or unevenness of mixed color is caused.

Recording liquid, liquid cartridge, liquid discharge device, and liquid discharge method


Apparatus for teaching the usage, spelling, and meaning of words, the components of the apparatus including structural units having letters and words superimposed thereon. Each structural unit relates a word with the initial letter thereof. Moreover, the structural units provide an arrangement by which one may spell and use words alone and in phrases and sentences.

1. Field of the Invention
The present invention relates to an educational apparatus and method for using the apparatus, more specifically, to an apparatus and method for teaching and building character.
2. Background
Young people may find education to be a foreign and intimidating experience. Toys, on the other hand, are a familiar and inviting medium among them. The use of toys in education therefore can help encourage young people to embrace the learning process. Children also may be hesitant to learn the spelling, meaning, and usage of particular words, such as descriptive words relating to personal behavior and character. A toy for teaching these elements therefore would help young people to learn the meaning and usage of such words.
Devices and systems for displaying indicia on structural units have been described in past publications. In some instances, the indicia-bearing devices would include a cubical structure with a plurality of faces, whereby each face has a single letter or word superimposed thereon. Furthermore, some indicia-bearing devices would provide a means for forming phrases and sentences.
The prior art discloses numerous toy block devices including alpha-numeric characters. For example, U.S. Pat. No. 3,670,427 issued on Jun. 20, 1972 to Stolpen discloses a language teaching apparatus whereby boxes have words superimposed thereon. Words are selected for a particular box based on the grammatical part and class of speech thereof. U.S. Pat. No. 3,728,800 issued on Apr. 24, 1973 to Magram discloses an educational apparatus comprising structural units which challenges one to create grammatically correct sentences. U.S. Pat. No. 4,508,347 issued on Apr. 2, 1985 to Shettler discloses an apparatus which includes structural units for creating letters of the alphabet. U.S. Pat. No. 5,275,567 issued on Jan. 4, 1994 to Whitfield discloses an apparatus which includes structural units whereby individual letters and corresponding Braille characters are superimposed thereon.
While such toys may assist in teaching the appearance of words, these devices do not provide a convenient method for teaching the usage, spelling, formation, and meaning of particular words. Moreover, these toys fail to provide structural units for simultaneously relating a descriptive word with a letter and challenging one to spell the words, make sentences out of the words and provide synonyms for the words.
For the foregoing reasons, there is a need for an apparatus for teaching children character and a method for teaching children character.

Apparatus and method for teaching character


In a semiconductor memory device having cylindrical capacitors, word lines and a bit line are formed on a semiconductor substrate. A cylindrical storage node is connected to a conductive layer. The cylindrical storage node is provided at its inner wall with protruded conductive conductors which protrudes in a radially inward direction of the cylindrical storage node. A surface of the cylindrical storage node is covered with a capacitor insulating film. The outer surface of the cylindrical storage node is covered with a cell plate with the capacitor insulating film therebetween.

1. Field of the Invention
The present invention relates in general to a semiconductor memory device, and in particular, to an improvement of a semiconductor memory device in which a sufficient capacitor capacity can be ensured even if degree of integration is increased. The present invention also relates to a method of manufacturing such a semiconductor memory device.
2. Description of the Related Art
In recent years, demands for semiconductor memory devices have been rapidly increased owing to remarkable spread of information equipments such as computers. In connection with function, such devices have been demanded that have a large scale storage capacity and can operate at a high speed. In compliance with these demands, technologies have been developed for improving degree of integration, response and reliability of the semiconductor memory devices.
Dynamic random access memories (DRAMs) have been known as a kind of semiconductor memory devices which enable random input and output of storage information. In general, the DRAM is formed of a memory cell array, which is a storage region storing a large number of storage information, and a peripheral circuitry required for external input and output.
FIG. 1 is a block diagram showing a structure of a conventional DRAM. In FIG. 1, a DRAM 1 includes a memory cell array 2 which stores data signals of stored in formation, a row and column address buffer 3 which externally receives an address signal for selecting a memory cell merely forming a storage circuit, a row decoder 4 and a column decoder 5 which decode the address signal to designate the memory cell, a sense refresh amplifier 6 which amplifies and reads the signal stored in the designated memory cell, data-in buffer 7 and a data-out buffer 8 for data input and output, and a clock generator 9 generating a clock signal. The memory cell array 2 which occupies a large area on the semiconductor chip is provided with a plurality of memory cells, which function merely to store the information and are disposed in a matrix form .
FIG. 2 is an equivalent circuit diagram showing memory cells for four bits forming the memory cell array. Each memory cell in the figure is formed of one MOS transistor and one capacitor connected thereto, and thus is of so-called an one-transistor/one-capacitor type. Since the memory cells of this type have a simple structure, the degree of integration of the memory cell array can be increased easily, and they have been widely used in DRAMs of a large capacity.
The memory cell of the DRAM can be classified into several types based on the structure of the capacitor.
FIG. 3 is a cross section of a memory cell having a typical stacked type capacitor in the prior art. Referring to FIG. 3, the memory cell includes one transfer gate transistor and one stacked type capacitor. The transfer transistor includes a pair of source/drain regions 11 formed at a surface of a silicon substrate 10, and gate electrodes (word lines) 12 formed on the surface of the silicon substrate 10 with an insulating layer therebetween. The stacked type capacitor is formed of a lower electrode (storage node) 14, which is extended over the gate electrode 12 and a field isolating film 13, and is connected to one of the source/drain regions 11, a dielectric layer 15 formed on the surface of the lower electrode 14, and an upper electrode (cell plate) 16 formed on the surface of the dielectric layer 15. The upper electrode 16 is covered with an interlayer insulating film 19 disposed on the silicon substrate 10. In the interlayer insulating film 19, there is provided a contact hole 18 through which the surface of the other source/drain region of the transfer gate transistor is exposed. A bit line 17 is connected to the other source/drain region 11 of the transfer gate transistor through the contact hole 18.
FIG. 4 is a plan showing a semiconductor memory device having a cylindrical capacitor, which belongs to another type of DRAM and is disclosed in Japanese Patent Laying-Open No. 02-89869 (1990). FIG. 5 is a cross section taken along line V--V in FIG. 4.
Referring to these figures, a plurality of word lines 12a, 12b, 12c, 12d and 12e are formed on the surface of the silicon substrate 10. Bit lines 21 extend perpendicularly to the word lines 12a, 12b, 12c, 12d and 12e. Memory cells are provided near crossings of the word lines and bit lines.
Each memory cell is formed of one transfer gate transistor 22 and one capacitor 23. The transfer gate transistor 22 includes a pair of source/drain regions 11 formed at the surface of the silicon substrate 10, and the gate electrodes (word lines 12a and 12b) formed on the surface of the silicon substrate 10. The word lines 12a, 12b, 12c and 12d are covered with an insulating layer 24 provided on the silicon substrate 10. In the insulating layer 24, there is provided a contact hole 25 through which one of the source/drain regions 11 is exposed.
Through the contact hole 25, a storage node 26 is connected to one of the source/drain regions 11. The storage node 26 includes a bottom conductive portion 27 and a side wall conductive portion 28. The bottom conductive portion 27 is in contact with one of the source/drain regions 11 through the contact hole 25 and extends along the surface of the insulating layer 24. The side wall conductive portion 28 is continuous with the outer periphery of the bottom conductive portion 27 and extends upwardly therefrom.
The surface of the storage node 26 is covered with a capacitor insulating film 29, and is further covered with a cell plate 30 with the capacitor insulating film 29 therebetween. The cell plate 30 is covered with an interlayer insulating film 31 provided on the silicon substrate 10. On the interlayer insulating film 31, there are provided interconnection layers 32, which are covered with a protection film 33 provided on the silicon substrate 10.
In the cylindrical capacitor having the aforementioned structure, since the storage node 26 has the side wall conductive portion 28 of which surface contributes to the capacitor capacity, the overall capacity of the capacitor is large.
A method of manufacturing the semiconductor memory device shown in FIG. 5 will be described below.
FIGS. 6-20 are fragmentary cross sections of the semiconductor memory device at a series of steps in a process of manufacturing the semiconductor memory device shown in FIG. 5.
Referring to FIG. 6, a field oxide film 13 is formed on the main surface of the silicon substrate 10 by the LOCOS method.
Referring to FIG. 7, a gate insulating film 34 is formed on the surface of the silicon substrate 10, and then, the word lines 12a, 12b, 12c and 12d made of polysilicon are formed thereon. The insulating layers 24 are formed to cover the word lines 12a, 12b, 12c and 12d. Using the word lines 12a, 12b, 12c and 12d covered with the insulating layers 24 as a mask, impurity ions are implanted into the surface of the silicon substrate 10 to form the source/drain regions 11.
Referring to FIG. 8, a layer of metal such as tungsten, molybdenum or titanium having a high melting point is deposited on the surface of the silicon substrate 10 for forming the bit line 17, and is patterned into a predetermined configuration. The layer thus patterned forms the bit line 17 which is in direct contact with one of the source/drain regions 11 of the transfer gate transistor. An insulating layer 35 is formed to cover the surface of the bit line 17.
Referring to FIG. 9, a first polysilicon layer 36 containing impurity introduced thereinto is deposited on the surface of the silicon substrate 10 by the CVD method.
Referring to FIG. 10, an insulating layer 37 made of a silicon oxide film is deposited on the surface of the silicon substrate 10.
Referring to FIG. 11, resist patterns 38 of a predetermined configuration are formed on the surface of the insulating layer 37. As will be seen later, a width w of the resist pattern 38 determines a distance between adjoining capacitors.
Referring to FIG. 12, the insulating layer 37 is selectively etched using the resist patterns 38 as a mask.
Referring to FIGS. 12 and 13, the resist patterns 38 are removed, and then a second polysilicon layer 39 containing impurity introduced thereinto is deposited on the whole surface of the silicon substrate 10 by the CVD method so that the second polysilicon layer 39 covers the side walls and upper end surfaces of the patterned insulating layers 37.
Referring to FIG. 14, a resist 40 is applied to the surface of the silicon substrate 10 so that the resist 40 fully covers the uppermost surfaces of the second polysilicon layer 39.
Referring to FIGS. 14 and 15, the resist 40 is etched back to expose the upper end surfaces of the second polysilicon layer 39.
Referring to FIGS. 15 and 16, the exposed upper end surfaces of the second polysilicon layer 39 are etched. Thereafter, the insulating layers 37 are removed by etching, e.g., with HF liquid.
Referring to FIGS. 16 and 17, anisotropic etching is effected to remove exposed portions 36a of the first polysilicon layer 36 in a self-aligning manner. Thereafter, the resist 40 is removed. Through these steps, the bottom conductive portion 27 and side wall conductive portion 28 of the storage node 26 are formed.
Referring to FIG. 18, the capacitor insulating film 29 made of, e.g., silicon nitride, silicon oxide, tantalum pentaoxide or hafnium oxide is formed on the surface of the storage node 26.
Referring to FIG. 19, the cell plate 30 is formed to cover the outer surface of the storage node 26 with the capacitor insulating film 29 therebetween. The cell plate 30 is made of material such as polysilicon containing impurity introduced thereinto.
Referring to FIG. 20, the interlayer insulating film 31 is formed on the whole surface of the silicon substrate 10 to cover the cell plate 30. The interconnection layers 32 having a predetermined configuration are formed on the interlayer insulating film 31. The protection film 33 covering the interconnection layers 32 is formed on the whole surface of the silicon substrate 10. Through the aforementioned steps, the semiconductor memory device shown in FIG. 5 is completed.
The semiconductor memory device having the cylindrical capacitors have the structure described above and is manufactured by the aforementioned method.
Meanwhile, such a method was recently proposed that, in order to increase the capacitor capacity, projections formed of silicon particles are provided at the surface of the cylindrical storage node so as to increase the surface area of the capacitor (IEDM, Technical Digest, 1992, pp 259-263).
FIG. 21 is a cross section of a semiconductor memory device having a cylindrical capacitor which is manufactured by the method proposed in the above reference.
The prior art shown in FIG. 21 differs from the prior art shown in FIG. 20 in that silicon particles 41 are provided on the outer surface of the storage node 26, the capacitor insulating film 29 is provided on the outer surface of the storage node 26 including the surfaces of the silicon particles 41, and the cell plate 30 is provided on the capacitor insulating film 29.
The semiconductor memory device shown in FIG. 21 is obtained only by an ideal manufacturing process, and has such a problem that a practical manufacturing process cannot produce the silicon particles 41 having a uniform diameter shown in the figure.
This problem will be described below with reference to the drawings.
FIG. 22 is a fragmentary cross section of the semiconductor memory device at a major step in the process of manufacturing the semiconductor memory device shown in FIG. 21.
The step shown in FIG. 22 is carried out between the steps shown in FIGS. 17 and 18.
The silicon particles 41 are formed on the side wall of the storage node 26 in the following manner.
The silicon substrate 10 provided with the storage node 26 is introduced into a pressure-reduced CVD chamber. A temperature of 600.degree. C. and a high vacuum state of not more than 1.times.10-7 Torr are maintained in the CVD chamber. Under there conditions, Si.sub.2 H.sub.6 gas or the like is flowed through the CVD chamber for ten seconds, so that minute cores of the silicon particles 41 of nearly hemispheric shapes are formed on the surfaces of the bottom conductive portion 27 and side wall conductive portion 28 of the storage node 26.
Referring to FIG. 22, the silicon particle generally has a size of 500 to 1000 .ANG.. However, if the surface state of the storage node 26 is uneven or the process condition is not uniform, the density and sizes of the silicon particles 41 fluctuate.
The uneven surface state of the storage node 26 may be caused, for example, if amorphous silicon at the surface of the storage node 26 is partially crystallized, if residue of resist and/or etching residue are present on the surface of the storage node, and if a natural oxide film is formed on the surface of the storage node. The nonuniform process condition may be caused, for example, by variation of the temperature and/or reduction of the vacuum in the CVD process.
If the sizes of the silicon particles 41 are uneven, a following problem is caused if a space between adjoining storage nodes is small in accordance with high density and high degree of integration of elements.
Referring to FIG. 23, the adjoining storage nodes 26, which are spaced by a short distance from each other, may be short-circuited via the silicon particles 41, resulting in bit error.
Even in the case where the short-circuit does not occur, the space between the adjoining storage nodes 26 is reduced by a distance corresponding to the thicknesses of the huge silicon particles 41, so that the capacitor insulating film 29 and cell plate 30 may not completely cover the outer surfaces of the storage nodes 26. This results in reduction of the memory cell characteristics.

Semiconductor memory device and method of manufacturing the same