Abstract: This is a method of fabricating a high-performance semiconductor device. The method comprises: forming a first insulating structure, preferably a layer of silicon nitride (e.g. region 24 in FIG. 2) on a layer of thermally grown oxide (e.g. region 22), on a substrate (e.g. region 20), preferably silicon; patterning and anisotropically etching the first insulating structure to expose a portion of the substrate and sidewalls of the first insulating structure; forming a second insulating structure, preferably a layer of oxide (e.g. region 28 in FIG. 3) on a layer of nitride (the bottom second insulating layer is preferably an etch-stop layer with respect to the removal of the top second insulating layer) (e.g. region 26 in FIG. 3), on the patterned first insulating structure, along the sidewalls of the first insulating structure, and on the exposed semiconductor substrate; anisotropically removing portions of the second insulating structure leaving a sidewall region of the second insulating structure (e.g.

Abstract: An active pull down circuit for a logic circuit, having a true and a complement output, a pull down transistor coupled to one of the true and complement outputs, a bias element for biasing the pull down transistor on, and a charge coupling element coupled between the other of the true and complement outputs and a base of the pull down transistor for coupling charge from the other output to the pull down transistor to turn on the latter harder when the other output goes low.

Abstract: A method is provided for synchronizing the time scale of a test device driver (12) with an e-beam tester. Test device driver (12) generates a test pattern which is applied to the functional inputs (18) of a device under test (16). A trigger and a synchronizing signal are generated with an identical time relationship to the test pattern. The trigger is applied to the trigger input of e-beam tester electronics and e-beam generator (38). The synchronizing signal is caused to appear on device under test (16). Using e-beam tester electronics and e-beam generator (38), waveforms are created of the synchronizing signal appearing on device under test (16) and test response signals also appearing thereon in response to application of the test pattern to functional inputs (18). The time relationship between the synchronizing signal and the test response signals can then be established through the waveforms.

Abstract: There is disclosed an exposure unit and method of operation having advantage of deformable mirror device (DMD) technology. The exposure unit is used to provide front end image processing for a xerographic process printing system. The unit, in one embodiment, is constructed as a unitary member having a lamp socket, a support for holding a flat DMD substrate, a set of light focusing lenses, an image focusing lens, a light baffle and an extra light trap chamber. The unit is separated from the xerographic drum by a solid base which contains a slot positioned so that the image from the image lens passes therethrough for supplying the image to the drum. The light bundle is directed to the xerographic drum location along an optical path formed by a system of fold mirrors in the lower body of the unitary member.

Abstract: A new class of CMOS integrated circuits, wherein the PMOS and NMOS devices are both configured as vertical transistors. One trench can contain a PMOS device, an NMOS device, and a gate which is coupled to control both the PMOS device and the NMOS device. Latchup problems do not arise, and n+ to p+ spacing rules are not required.

Abstract: A signal transmission circuit (10) for transmitting a signal (V.sub.IN) between dies on a wafer. A transmission node (72) is precharged to a first voltage (70) that is representative of a first of a plurality of bit values in response to the actuation of a gate (48) of a P-channel transistor (50) by a first state control signal (.phi..sub.1). At a later time, a second state of the control signal (.phi..sub.1) actuates a pass gate transistor (38) to couple the end of a first transmission signal line segment (32) to a node (40). A preselected state of the node (40) will cause the signal node (72) to be grounded to a logic zero (74). The signal node (72) is selectively coupled to a latch (92) by a one-shot pass gate (76). The output (102) of the latch (92) is connected to the beginning end of a second transmission line segment (104). The transmission of the signal thus relies on the state of the signal node (72) rather than on the presence or absence of a connection directly to a voltage supply such as V.sub.dd.

Abstract: An apparatus and method for translating voltages between logic levels is provided having an input section (11), a level shifter section (89) and an output section (137). Input section (11) provides two control voltages to the level shifter section (89) in response to an input signal provided at input terminal (12). Level shifter section (89) comprises two inverters coupled to the control voltages. One inverter comprises p channel field-effect transistor (90) and n channel field-effect transistor (98). Another inverter comprises p channel field-effect transistor (106) and n channel field-effect transistor (114). For each inverter, the channel of the p channel field-effect transistor is over twice as wide as the channel of the n channel field-effect transistors. Each transistor (90, 98, 106 and 114) conducts current in response to a control voltage being anywhere within the voltage range, such that outputs of the inverters transition quickly in reponse to a transition of the control voltages.

Abstract: The described embodiments of the present invention provide a structure and method for easily incorporating a high voltage lateral bipolar transistor in an integrated circuit. A buried base contact is formed and the base itself is formed of a well region in the integrated circuit. An oppositely doped well region is formed surrounding the collector region in the lateral PNP transistor. This collector well is formed of the opposite conductivity type of the base well. Contact to the collector and a heavily doped emitter are then formed in the collector well and base well, respectively. The more lightly doped collector well provides a thick depletion region between the collector and base and thus provides higher voltage operation. The positioning of the base/collector junction to the collector well at base well junction also reduces the spacing between the collector and the emitter.

Abstract: A method of making single crystal semiconductor grade silicon spheres for solar cells and the like from metallurgical grade silicon. The process comprises sizing metallurgical grade silicon particles to a desired range and oxidizing the outer surfaces of the particles to form a silicon dioxide skin thereon. The particles are then heated to melt the silicon within the skin to cause impurities to travel into the skin. This is made possible because single crystals are formed. The skin and impurities therein are then etched off and the remaining particles are again treated to form a skin with subsequent melt of the interior silicon and removal of the skin, the cycle being repeated until the desired degree of silicon purity is obtained. An intermediate shotting step can yield spheres of substantially uniform diameter for use as the feed for the repeat cycle.

Abstract: Integrated circuits and fabrication methods incorporating both NPN (192, 194, 210) and PNP (196, 121, 124) heterojunction bipolar transistors together with N channel (198, 200, 216, 218) and P channel (202, 204, 220, 222) JFETs on a single substrate as illustrated in FIG. 10. MESFETs may also be integrated on the substrate.

Abstract: A delay stage (60) has a delay period of reduced dependence on the level of a first voltage supply (V.sub.dd). First and second inverter stages (78, 90) each have p-channel transistors (68, 86) and n-channel transistors (70, 88). The gates (64, 66) of the first inverter pair are connected to an input node (62). A fixed resistor (72) is inserted between the current path of the p-channel transistor (68) of the first inverter pair and a signal node (76). The current path of the n-channel transistor (66) of the first inverter is operable to connect the signal node (76) to ground. A MOSFET capacitor (80) is coupled to the signal node (76), as are the gates (82, 84) of the second inverter transistor (86, 88). The current path of the p-channel transistor (86) of the second inverter is operable to connect the voltage supply (V.sub.dd) to an output node (92), and the current path of the n-channel transistor (88) of the second inverter (90) is operable to connect the output node (92) to ground.

Abstract: An integrated circuit (10) which includes primary circuit (12) and secondary circuit (17). An enabling circuit (16) allows package pins (15) to be shared between the primary circuit (12) and secondary circuit (17) responsive to voltages on the package pins (15). Enabling circuit (16) further includes disabling circuitry to disable the secondary circuit (17) responsive to a predetermined voltage on the V.sub.cc pin and enables the secondary circuit (17) responsive to a ground voltage on the V.sub.cc pin.

Abstract: An improved memory cell 118 is provided utilizing transistor pairs 142, 144 ands 160, 162 as dual purpose transistor pairs for the two modes of operation of the cell. During the first or non-access mode of operation, the transistor pairs operate as switched capacitive elements in order to provide an equivalent resistance between bit line 140 and first node 26 and inverted bit line 158 and second node 130. Control circuit 119 maintains bit lines 140 and inverted bit line 158 high during this non-access mode. During the second or access mode of operation, each transistor pair operates as a respective pass transistor for connecting bit line 140 to first node 126 and inverted bit line 158 to second node 130 so that data may be read from, or written to, the cross-coupled transistors 120 and 122.

Abstract: A programmable device (10) is formed from a silicided MOS transistor. The transistor (10) is formed at a face of a semiconductor layer (12), and includes a diffused drain region (17, 22) and a source region (19, 24) that are spaced apart by a channel region (26). At least the drain region (22) has a surface with a silicided layer (28) formed on a portion thereof. The application of a programming voltage in the range of ten to fifteen volts from the drain region (17, 22) to the source region (19, 24) has been discovered to reliably form a melt filament (40) across the channel region (26). A gate voltage (V.sub.g) may be applied to the insulated gate (14) over the channel region (26) such that a ten-volt programming voltage (V.sub.PROG) will cause melt filaments to form in those transistors to which the gate voltage is applied, but will not cause melt filaments to form in the remaining transistors (10) of an array.

Abstract: Vertical AlGaAs heterojunction bipolar transistors and GaAs junction field effect transistors are fabricated on a single gallium arsenide (GaAs) substrate to form an integrated circuit structure. The integration of these devices is made possible by a novel method of fabricating heterojunction inverted transistor integrated logic (HI2L) transistors with emitter reigons on the bottom (contacted through the substrate) while simultaneously forming the JFET structure with no additional processing steps. An ion implant technique is employed which uses an acceptor material to create a P type region, boron or protons to create insulating regions, and silicon or selenium to create an N type region. A zinc diffusion is used to form the bipolar P type ohmic contact regions and JFET gate regions in one operation. Bipolar collector and JFET source and drain metallization patterns are formed simultaneously followed by the simultaneous formation of bipolar base and JFET metallization patterns.

Abstract: The disclosure relates to a circuit and method of reducing inductive voltage spikes caused by an abrupt change in current by an output transistor, by providing an input node for receiving an input voltage signal, providing an output node, providing a first transistor coupled to the output node, receiving a predetermined voltage at the input node, controlling voltage control circuitry coupled between the input node and the first transistor and responsive to the predetermined voltage at the input node to control the voltage driving the first transistor with respect to time to provide a constant rate of change of current with respect to time in the first transistor and providing a second transistor coupled to the output node in parallel with the first transistor which turns on prior to the first transistor.

Abstract: Hysteresis effects in low frequency field effect transistor circuits are minimized by using biasing or clamping circuits including field effect transistors.

Abstract: Disclosed is a bipolar transistor and a method of fabrication thereof compatible with MOSFET devices. A transistor intrinsic base region (54) is formed in the face of a semiconductor well (22), and covered with a gate oxide (44). The gate oxide (44) is opened, and doped polysilicon is deposited thereover to form a polyemitter structure (68) in contact with the base region (54). Sidewall oxide (82, 84) is formed on the polyemitter strucure (60). A collector region (90) and an extrinsic base region (100) are formed in the semicondcutor well (22) and self aligned with respect to opposing side edges of the polyemitter sidewall oxide (82, 84).

Abstract: An isolation structure for bipolar and CMOS circuits formed during the same processing steps to optimize the integration of bipolar and CMOS circuits. A deep trench (46) is formed in a semiconductor circuit for providing deep isolation for bipolar circuits. A shallow recess (56) is then formed simultaneous with a stepped sidewall structure of the deep trench. The recess (56) and the trench (46) are covered by an insulating oxide (60). and thereafter filled with an undoped polysilicon (62) to form the different isolating structures for the different types of circuits.

Abstract: A process is disclosed with integrated steps for fabricating bipolar and CMOS transistors. Mask, patterning and implanting steps are highly integrated to reduce the fabrication complexity. The integrated steps include a split level polysilicon step wherein PMOS and NMOS gate conductors and a bipolar emitter structure is formed. The polysilicon is heavily doped which forms MOS transistor gate electrodes, and another high impurity concentration area which is later diffused into an underlying bipolar base region. Small area, high performance transistors can be fabricated with laterally extending contact strips. Alignment of electrode metallization patterns is thus less critical.