International Business Machines Corporation

Lawrence F Wagner, Jr

Louis L Hsu

Fariborz Assaderaghi

Chang-Ming Hsieh

Ronald W Knepper

Shaw-Ning Mei

George E Smith, Iii

Timothy L Walters

Jack Allan Mandelman

Ghavam G Shahidi

Randy Lee Wolf

John Matthew Safran

Paul David Muench

Jean-Oliver Plouchart

Raminderpal Singh

Heemyong Park

Phung T Nguyen

Richard Daniel Kimmel

Yue Tan

Mario M Pelella

Mohamed Talbi

Kun Wu

Disclosed are embodiments of an improved integrated circuit switching device that incorporates multiple sets of series connected field effect transistors with each set further connected in parallel between two nodes. The sets are arranged in a linear fashion with each set positioned such that it is in contact with and essentially symmetrical relative to an adjacent set. Arranging the sets in this manner allows adjacent diffusion regions of the same type (i.e., sources or drains) from adjacent sets to be merged. Merging of the diffusion regions provides several benefits, including but not limited to, reducing the device size, reducing the amount of required wiring for the device (i.e., reducing resistance) and reducing side capacitance between the now merged diffusion regions and the substrate. Also disclosed are embodiments of an associated design structure for the device and an associated method of forming the device.

Merged field effect transistor cells for switching

A sub-circuit based extraction method which extracts a multi-finger MOS transistor directly as a sub-circuit is described. By adding three marking layers, the method provides the layout extracted netlist with a complete list of device geometric parameters corresponding to the device properties as presented in the sub-circuit model based schematic netlist. By performing a layout-versus-schematic comparison based on all geometric parameters extracted, the layout checking is performed in a complete and accurate way where each device parameter is checked against the corresponding design schematic. This complete and accurate geometric parameter comparison enhances the confidence level of the layout physical verification.

Method of checking the layout versus the schematic of multi-fingered MOS transistor layouts using a sub-circuit based extraction

Capacitance between source/drain and p-type substrate in SOI CMOS circuits is reduced by implanting an n-type layer below the oxide layer, thereby forming a fully depleted region that adds to the thickness of the oxide layer, while creating a junction capacitance region that reduces the total device to substrate capacitance.

Integrated circuits with reduced substrate capacitance

A process for obtaining accurate DC convergence in a DC phase of a circuit simulation program for models of field effect transistors (FETs) on a silicon-on-insulator (SOI) substrate. The process comprises running iterations of the DC phase of the circuit simulation program such that error criteria are satisfied, wherein the pseudo-time step changes at each iteration until it reaches a value such that a desired current value is achieved. DC convergence is also achieved by reducing the magnitude of the capacitive and/or charge elements connected to the floating body regions of the field effect transistors on the silicon-on-insulator substrate model during the DC phase to achieve a desired current value.

Method for obtaining DC convergence for SOI FET models in a circuit simulation program

A method for use in electronic design models encoded into design software for use in SOI based FET logic design includes simulation of an SOI device by and setting a floating body voltage to any desired value at any time during the simulation, by adding to the model an ideal voltage source, whose value is a desired body voltage, in series with an ideal current source, whose value is a constant times the voltage across itself. When the constant is zero, no current can flow, and any additional components have no effect on the circuit. When the constant is non-zero, said ideal current source appears to be the same as a resistor such that current can flow in to or out from the body node, setting its voltage. The constant is kept zero at all times, except when it is desired to change the body voltage. The body voltage can be reset at any time to solve the problem of successive delays in one simulation run and resetting the voltage before each delay measurement starts. To solve the problem of predicting the delay in a delay predictor (for example, delay rules generation), the offset from the body voltage as a part of the best case/worst case determination is included. The improved process employs a topological analysis for circuit elements to determine whether the element falls in one of several categories, and in the process determines which elements of a circuit might be in AC equilibrium.

Method for use in simulation of an SOI device

A method for use in electronic design models encoded into design software for use in SOI based FET logic design includes simulation of an SOI device and setting a floating body voltage to any desired value at any time during the simulation, by adding to the model an ideal voltage source, whose value is a desired body voltage, in series with an ideal current source, whose value is a constant times the voltage across itself. When the constant is zero no current can flow, and any additional components have no effect on the circuit. When the constant is non-zero, said ideal current source appears to be the same as a resistor such that, current can flow in to or out from the body node, setting its voltage. The constant is kept zero at all times, except when it is desired to change the body voltage. The body voltage can be reset at any time to solve the problem of successive delays in one simulation run and resetting the voltage before each delay measurement starts. To solve the problem of predicting the delay in a delay predictor (for example, NDR rules generation), the offset from the body voltage as a part of the best case/worst case determination is included.

Producing a gap between a source and/or drain region of a silicon-on-insulator (SOI) field effect transistor which is less than the thickness of a depletion region normally surrounding the source and/or drain region, preferably at zero volts bias, permits gain of a parasitic bipolar transistor formed therewith to be transiently reduced and the effective base-emitter junction capacitance to be transiently increased during only modes of operation in which the parasitic bipolar conduction dominates normal operation of the field effect transistor. Such transient reduction of gain coupled with a transient reduction of high frequency response reduces the parasitic bipolar current spike to a degree greater than previously achievable and is fully compatible with other techniques of reducing such current spike. As applied to an SOICMOS SRAM, the transistor structure including such a gap is effective in suppressing half-select write disturb effects while maintaining the benefits of excess charge storage and floating body effects in the transistor.

SOI FET design to reduce transient bipolar current

A transistor with silicon on insulator (SOI) intrinsic base and a collector each formed by a low temperature epitaxial process and each orientated vertically with respect to the (SOI) substrate. The base width can be as narrow as in a conventional vertical transistor. Similarly, the collector width can be precisely controlled.

Vertical-gate CMOS compatible lateral bipolar transistor

Method of forming a novel vertical-gate CMOS compatible lateral bipolar

A lateral bipolar transistor has an extrinsic base layer on either side of a centrally disposed emitter layer and an intrinsic base and a collector oriented perpendicularly to the extrinsic base and collector layers.

Novel vertical-gate CMOS compatible lateral bipolar transistor

An integrated gate and semiconductor barrier layer diode which functions as a regular diode when the gate is turned off and as, a Schottky barrier diode with the gate turned on.

Growing community of inventors

Fishkill, NY, United States of America

Lawrence F Wagner, Jr