Narrow Results

The spatial wavefunction-switched field-effect transistor (SWSFET) is one of the promising quantum well devices that transfers electrons from one quantum well channel to the other channel based on the applied gate voltage. This eliminates the use of more transistors as we have coupled channels in the same device operating at different threshold voltages. This feature can be exploited in many digital integrated circuits thus reducing the count of transistors which translates to less die area. The simulations of basic sequential circuits like SR latch, D latch and flip flop are presented here using SWSFET based logic gates. The circuit model of a SWSFET was developed using Berkeley short channel IGFET model (BSIM 3).

This paper presents Spatial Wavefunction Switched (SWS)-FETs have been proposed to implement ternary and quaternary logic, 2-bit DRAM cells, and static random-access memories (SRAMs) in nMOS-SWS and CMOS-SWS configurations. This paper presents simulation of a 1-bit Full Adder using n-SWS-FETs. In addition, simulation of 2-bit SRAMs is presented for a quantum dot channel and a four quantum well nSWS-FET.SRAMs.

Multi-valued logic using multi-state spatial wavefunction switched (SWS)-FETs offers overall reduction in size and power as compared to conventional FET based circuits. This paper presents the design of compact 3-bit Analog-to-Digital Converters (ADC) implemented with SWS-FETs. A novel multi-valued Threshold Inverter Quantization (TIQ) based voltage comparator using SWS FET transistors has been proposed. Unlike conventional FETs, SWS-FETs are comprised of two or more vertically stacked coupled quantum well or quantum dot channels, and the spatial location of carriers within these channels is used to encode the logic states (00), (01), (10) and (11). The SWS-FET logic and circuit models for complementary (n- and p-channel) using 20 nm technology are presented. The digital logic circuit in the ADC is developed using SWS-FET based quaternary logic circuits. The accuracy of the SWS-FET circuits is verified by SWS-FET models in Cadence. The simulations for the SWS FET are based on integration of the Berkeley Short-channel IGFET Model (BSIM4.6) and the Analog Behavioral Model (ABM). The ADC circuit design using SWS-FETs reduce the number of transistors by 55% compared with CMOS counterpart.

This paper investigates physics based equivalent circuits for spatial wavefunctions switched (SWS) field-effect transistors (FETs). This will lead to improved analog behavioral models (ABMs) for 2-bit/4-state logic gates, SRAMs, and registers. Model parameters related to 65 nm technology were used to simulate ID-VD characteristics, transconductance g_m and channel conductance g_D using Cadence. SWSFET physics based analytical equations were used to simulate using MATLAB SIMULINK and compare with Cadence simulations. Equivalent circuit utilizes different values of equivalent oxide thickness for the lower W2 and upper W1 quantum well channels. The methodology is similarly applicable to two-channel quantum dot FET. The methodology can be further extended to model and simulate multiple channel SWS-FET devices.

A Threshold Inverter Quantizer (TIQ)-based voltage comparator is used to quantize analog input signal in flash ADC designs. This quantizer is based on the systematic sizing of CMOS inverter thus eliminating resistor array which is used for conventional comparator array. Such an implementation removes static power during quantization of analog input signal. This paper presents a simulation of TIQ 2-bit-based comparator using spatial wavefunction switched (SWS) field effect transistor (FET)-based CMOS inverters. The inverters use 4-state SWSFETs. Unlike conventional FETs, SWSFETs consist of two or more vertical coupled arrays of either quantum dot or quantum well channels, where the spatial location of carriers within these channels is used to encode the logic states (00), (01), (10), and (11). The TIQ-based comparator circuit presented here is based on the 2-bit SWS-CMOS inverter. The schematic of the ADC comparator circuit is demonstrated as well as the 2-bit ADC configuration cascading two 2-bit SWSFET-based inverters in CMOS-X. The circuit simulation was done in Cadence and SWSFET was modeled by integrating Berkeley Short-Channel IGFET Model (BSIM) and the Analog Behavioral Model (ABM). The 2-bit comparator circuit provides a four-state logic output voltage for any given analog input signal.

This paper presents Spatial Wavefunction Switched (SWS)-FETs have been proposed to implement ternary and quaternary logic, 2-bit DRAM cells, and static random-access memories (SRAMs) in nMOS-SWS and CMOS-SWS configurations. This paper presents simulation of a 1-bit Full Adder using n-SWS-FETs. In addition, simulation of 2-bit SRAMs is presented for a quantum dot channel and a four quantum well nSWS-FET.SRAMs.

Multi-valued logic using multi-state spatial wavefunction switched (SWS)-FETs offers overall reduction in size and power as compared to conventional FET based circuits. This paper presents the design of compact 3-bit Analog-to-Digital Converters (ADC) implemented with SWS-FETs. A novel multi-valued Threshold Inverter Quantization (TIQ) based voltage comparator using SWS FET transistors has been proposed. Unlike conventional FETs, SWS-FETs are comprised of two or more vertically stacked coupled quantum well or quantum dot channels, and the spatial location of carriers within these channels is used to encode the logic states (00), (01), (10) and (11). The SWS-FET logic and circuit models for complementary (n- and p-channel) using 20 nm technology are presented. The digital logic circuit in the ADC is developed using SWS-FET based quaternary logic circuits. The accuracy of the SWS-FET circuits is verified by SWS-FET models in Cadence. The simulations for the SWS FET are based on integration of the Berkeley Short-channel IGFET Model (BSIM4.6) and the Analog Behavioral Model (ABM). The ADC circuit design using SWS-FETs reduce the number of transistors by 55% compared with CMOS counterpart.

This paper investigates physics based equivalent circuits for spatial wavefunctions switched (SWS) field-effect transistors (FETs). This will lead to improved analog behavioral models (ABMs) for 2-bit/4-state logic gates, SRAMs, and registers. Model parameters related to 65 nm technology were used to simulate ID-VD characteristics, transconductance g_m and channel conductance g_D using Cadence. SWSFET physics based analytical equations were used to simulate using MATLAB SIMULINK and compare with Cadence simulations. Equivalent circuit utilizes different values of equivalent oxide thickness for the lower W2 and upper W1 quantum well channels. The methodology is similarly applicable to two-channel quantum dot FET. The methodology can be further extended to model and simulate multiple channel SWS-FET devices.

A Threshold Inverter Quantizer (TIQ)-based voltage comparator is used to quantize analog input signal in flash ADC designs. This quantizer is based on the systematic sizing of CMOS inverter thus eliminating resistor array which is used for conventional comparator array. Such an implementation removes static power during quantization of analog input signal. This paper presents a simulation of TIQ 2-bit-based comparator using spatial wavefunction switched (SWS) field effect transistor (FET)-based CMOS inverters. The inverters use 4-state SWSFETs. Unlike conventional FETs, SWSFETs consist of two or more vertical coupled arrays of either quantum dot or quantum well channels, where the spatial location of carriers within these channels is used to encode the logic states (00), (01), (10), and (11). The TIQ-based comparator circuit presented here is based on the 2-bit SWS-CMOS inverter. The schematic of the ADC comparator circuit is demonstrated as well as the 2-bit ADC configuration cascading two 2-bit SWSFET-based inverters in CMOS-X. The circuit simulation was done in Cadence and SWSFET was modeled by integrating Berkeley Short-Channel IGFET Model (BSIM) and the Analog Behavioral Model (ABM). The 2-bit comparator circuit provides a four-state logic output voltage for any given analog input signal.