Abstract: A semiconductor memory device having a thyristor is manufactured in a manner that makes possible self-alignment of one or more portions of the thyristor. According to an example embodiment of the present invention, a gate is formed over a first portion of doped substrate. The gate is used to mask a portion of the doped substrate and a second portion of the substrate is doped before or after a spacer is formed. After the second portion of the substrate is doped, the spacer is then formed adjacent to the gate and used to mask the second portion of the substrate while a third portion of the substrate is doped. The gate and spacer are thus used to form self-aligned doped portions of the substrate, wherein the first and second portions form base regions and the third portion form an emitter region of a thyristor.

Abstract: Switching times of a thyristor-based semiconductor device are improved by enhancing carrier drainage from a buried thyristor-emitter region. According to an example embodiment of the present invention, a conductive contact extends to a doped well region buried in a substrate and is adapted to drain carriers therefrom. The device includes a thyristor body having at least one doped emitter region buried in the doped well region. A conductive thyristor control port is adapted to capacitively couple to the thyristor body and to control current flow therein. With this approach, the thyristor can be rapidly switched between resistance states, which has been found to be particularly useful in high-speed data latching implementations including but not limited to memory cell applications.

Abstract: A semiconductor device includes a thyristor designed to reduce or eliminate manufacturing and operational difficulties commonly experienced in the formation and operation of NDR devices. According to one example embodiment of the present invention, the semiconductor substrate is trenched adjacent a doped or dopable substrate region, which is formed to include at least two vertically-adjacent thyristor regions of different polarity. A capacitively-coupled control port for the thyristor is coupled to at least one of the thyristor regions. The trench also includes a dielectric material for electrically insulating the vertically-adjacent thyristor regions. The thyristor is electrically connected to other circuitry in the device, such as a transistor, and used to form a device, such as a memory cell.

Abstract: A thyristor-based semiconductor device exhibits a relatively increased base-emitter capacitance. According to an example embodiment of the present invention, a base region and an adjacent emitter region of a thyristor are doped such that the emitter region has a lightly-doped portion having a light dopant concentration, relative to the base region. In one embodiment, the thyristor is implemented in a memory circuit, wherein the emitter region is coupled to a reference voltage line and a control port is arranged for capacitively coupling to the thyristor for controlling current flow therein. In another implementation, the thyristor is formed on a buried insulator layer of a silicon-on-insulator (SOI) structure. With these approaches, current flow in the thyristor, e.g., for data storage therein, can be tightly controlled.

Abstract: A semiconductor device having a thyristor is arranged in a manner that reduces or eliminates manufacturing difficulties commonly experienced in the formation of such devices, as well as facilitates the implementation of the semiconductor device in a variety of applications. According to an example embodiment of the present invention, a thyristor is formed having some or all of the body of the thyristor extending above a substrate surface of a semiconductor device. The semiconductor device includes at least one transistor having source/drain regions formed in the substrate prior to the formation of the thyristor. One or more layers of material are deposited on the substrate surface and used to form a portion of a body of the thyristor that includes anode and cathode end portions. Each end portion is formed having a base region and an emitter region, and at least one of the end portions includes a portion that is in the substrate and electrically coupled to the transistor.

Abstract: A semiconductor device is adapted to inhibit the formation of a parasitic MOS-inversion channel between an emitter region and a gated base in a capacitively-coupled thyristor device. According to an example embodiment of the present invention, a thyristor having first and second base regions coupled between emitter regions is gated, via one of the base regions, to a control port. The control port exhibits a workfunction between the control port and the base region that inhibits the formation of a conductive channel between the base region and an adjacent emitter region, such as when the semiconductor device is in a standby and/or a read mode for memory implementations. The workfunction is selected such that the parasitic MOS-inversion channel would turn on is sufficiently high to enable the operation of the device at voltages that are optimized for a particular implementation while remaining below VT.

Abstract: Parasitic current leakage from a thyristor-based semiconductor device is inhibited. According to an example embodiment of the present invention, a thyristor-based semiconductor device includes a thyristor body portion and a control port located in a substrate, the control port being adapted for capacitively coupling to the thyristor body portion for controlling current flow therein. The substrate further includes a doped circuit region separated by a channel region from another doped region of similar polarity in the substrate. The control port faces the channel region in the substrate, and the channel region is susceptible to current leakage in response to voltage pulses being applied to the control port for controlling current flow in the thyristor.

Abstract: A semiconductor device is formed including a substrate having an upper surface, a thyristor region in the substrate and a control port adapted for capacitively coupling to at least a portion of the thyristor region via a dielectric material. According to an example embodiment of the present invention, a trench is formed in the substrate and subsequently filled with materials including dielectric material and a control port. The control port is adapted for capacitively coupling to the thyristor via the dielectric material for controlling current flow in the thyristor (e.g., for causing an outflow of minority carriers from a portion of the thyristor for switching the thyristor from conducting state to a blocking state). A portion of the substrate adjacent to the upper surface is implanted with a species of ions, and the dielectric material via which the control port capacitively couples to the thyristor does not include the species of ions.

Abstract: A semiconductor device is formed having a thyristor, a pass device and a conductive shunt that electrically connects an emitter region of the thyristor with a node near an upper surface of the substrate. In one example embodiment of the present invention, the conductive shunt is formed in a trench in a substrate and extending from an upper surface of the substrate to an emitter region of a vertical thyristor, with the emitter region being in the substrate and below the upper surface. In one implementation, the thyristor includes a thyristor body and a control port, with an N+ emitter region of the thyristor body being in the substrate and below and upper surface thereof. A pass device is formed adjacent to the thyristor, and the conductive shunt is formed in a trench extending from the N+ emitter region to a source/drain region of the pass device.

Abstract: A semiconductor device having a thyristor is manufactured in a manner that reduces or eliminates manufacturing difficulties commonly experienced in the formation of such devices. According to an example embodiment of the present invention, a thyristor is formed having some or all of the body of the thyristor extending above a substrate surface of a semiconductor device. The semiconductor device includes at least one transistor having source/drain regions formed in the substrate prior to the formation of the thyristor. One or more layers of material are deposited on the substrate surface and used to form a portion of a body of the thyristor that includes anode and cathode end portions. Each end portion is formed having a base region and an emitter region, and at least one of the end portions includes a portion that is in the substrate and electrically coupled to the transistor. A control port is formed capacitively coupled to at least one of the base regions.

Abstract: A non-volatile memory cell (FIG. 3) is provided which includes three transistors, a floating gate non-volatile storage transistor (303) and two cascode connected select transistors (301-302). The two cascoded select transistors (301-302) act together to block the programming voltage when the memory cell is included in an array, and the memory cell is not selected for programming. A value of an unselect voltage applied to the gate of the first cascode connected transistor (301) is set to prevent breakdown of the oxide in the first cascode transistor (301) as well as the second cascode transistor (302). A value of an unselect voltage applied to the gate of the second cascode connected transistor (302) can be selected so that the voltage passed to the floating gate storage transistor (303) will not result in a program drain disturb, or source disturb condition.

Abstract: A CMOS memory cell (FIG. 1) is provided which includes a PMOS transistor (102) and an NMOS transistor (104) with a common floating gate and common drains configured to prevent a large drain of Icc current from a power supply during power-up. To prevent the large Icc during power-up, the threshold voltages of the PMOS transistor (102) and NMOS transistor (104) are set so that the PMOS transistor (102) and NMOS transistor (104) do not turn on together, irrespective of charge initially stored on the floating gate. Without such thresholds, a significant drain of current Icc from the power supply connection Vcc can occur since charge initially on the floating gate leaves both the PMOS transistor (102) and the NMOS transistor (104) on creating a path for Icc from Vcc to Vss.

Abstract: A non-volatile memory cell (FIG. 3) is provided which includes three transistors, a floating gate non-volatile storage transistor (303) and two cascode connected select transistors (301-302). The two cascoded select transistors (301-302) act together to block the programming voltage when the memory cell is included in an array, and the memory cell is not selected for programming. A value of an unselect voltage applied to the gate of the first cascode connected transistor (301) is set to prevent breakdown of the oxide in the first cascode transistor (301) as well as the second cascode transistor (302). A value of an unselect voltage applied to the gate of the second cascode connected transistor (302) can be selected so that the voltage passed to the floating gate storage transistor (303) will not result in a program drain disturb, or source disturb condition.

Abstract: A thyristor-based semiconductor device has a thyristor that exhibits increased capacitive coupling between a conductive structure and a portion of a thyristor. According to an example embodiment of the present invention, the thyristor-based semiconductor device is manufactured having an extended portion that is outside a current path through the thyristor and that capacitively couples a conductive structure to a portion of the thyristor for controlling the current through the path. In one particular implementation, the extended portion extends from a base region of the thyristor and is outside of a current path through the base region and between an adjacent base region and an adjacent emitter region. A gate is formed capacitively coupled to the base region via the extended portion. In this manner, the control of the thyristor with the gate exhibits increased capacitive coupling, as compared to the control without the extended portion.

Abstract: The present invention teaches a method and system for disconnecting shorted decoupling capacitors, wherein a semiconductor chip having a plurality of redundant decoupling capacitors. Each of the capacitors is coupled, by means of a link, to a bus having a predetermined voltage. Each link is accessible to light emissions, in planar view. The system comprises a tester for testing the operability of each of the capacitors. In a preferred embodiment, the tester comprises a heating element and a high voltage stress testing element. Under thermal and voltage stress, an infrared signal identifying shorted decoupling capacitors is generated by shorted decoupling capacitors. The system further comprises a sensor for sensing the infrared signal. In one embodiment of the present invention, the sensor comprises an emission microscope for multilevel inspection ("EMMI"). Each inoperable capacitor is decoupled from the bus by disintegrating the link with a laser in response to the infrared signal.

Abstract: The present invention teaches a method and system for disconnecting shorted decoupling capacitors, wherein a semiconductor chip having a plurality of redundant decoupling capacitors. Each of the capacitors is coupled, by means of a link, to a bus having a predetermined voltage. Each link is accessible to light emissions, in planar view. The system comprises a tester for testing the operability of each of the capacitors. In a preferred embodiment, the tester comprises a heating element and a high voltage stress testing element. Under thermal and voltage stress, an infrared signal identifying shorted decoupling capacitors is generated by shorted decoupling capacitors. The system further comprises a sensor for sensing the infrared signal. In one embodiment of the present invention, the sensor comprises an emission microscope for multilevel inspection ("EMMI"). Each inoperable capacitor is decoupled from the bus by disintegrating the link with a laser in response to the infrared signal.