The previous report (XI) gave the electrochemical-potential theory of the Bipolar Field-Effect Transistors. This report (XII) gives the drift-diffusion theory. Both treat 1-gate and 2-gate, pure-base and impure-ba...The previous report (XI) gave the electrochemical-potential theory of the Bipolar Field-Effect Transistors. This report (XII) gives the drift-diffusion theory. Both treat 1-gate and 2-gate, pure-base and impure-base, and thin and thick base. Both utilize the surface and bulk potentials as the parametric variables to couple the voltage and current equations. In the present drift-diffusion theory, the very many current terms are identified by their mobility multiplier for the components of drift current,and the diffusivity multiplier for the components of the diffusion current. Complete analytical driftdiffusion equations are presented to give the DC current-voltage characteristics of four common MOS transistor structures. The drift current consists of four terms: 1-D (One-Dimensional) bulk charge drift term, 1-D carrier space-charge drift term,l-D Ex^2 (transverse electric field) drift term,2-D drift term. The diffusion current consists of three terms: 1-D bulk charge diffusion term,l-D carrier space-charge diffusion term,and 2-D diffusion term. The 1-D Ex^2 drift term was missed by all the existing transistor theories, and contributes significantly, as much as 25 % of the total current when the base layer is nearly pure. The 2-D terms come from longitudinal gradient of the longitudinal electric field,which scales as the square of the Debye to Channel length ratio, at 25nm channel length with nearly pure base, (LD/L)^2 = 10^6 but with impurity concentration of 10^18cm^-3 , (LD/L)^2 = 10^-2 .展开更多
This paper reports the DC steady-state voltage and current transfer characteristics and power dissipation of the Complimentary Metal-Oxide-Silicon (CMOS) voltage-inverter circuit using one physical Bipolar Field-Eff...This paper reports the DC steady-state voltage and current transfer characteristics and power dissipation of the Complimentary Metal-Oxide-Silicon (CMOS) voltage-inverter circuit using one physical Bipolar Field-Effect Transistor (BiFET) of nanometer dimensions. The electrical characteristics are numerically obtained by solving the five partial dif- ferential equations for the transistor structure of two MOS-gates on the two surfaces of a thin pure silicon base layer with electron and hole contacts on both ends of the thin base. Internal and CMOS boundary conditions are used on the three potentials (electrostatic and electron and hole electrochemical potentials). Families of curves are rapidly computed using a dual-processor personal computer running the 64-bit FORTRAN on the Windows XP operating system.展开更多
We explore 10-nm wide Si nanowire (SiNW) field-effect transistors (FETs) for logic applications, via the fabrication and testing of SiNW-based ring oscillators. We report on SiNW surface treatments and dielectric ...We explore 10-nm wide Si nanowire (SiNW) field-effect transistors (FETs) for logic applications, via the fabrication and testing of SiNW-based ring oscillators. We report on SiNW surface treatments and dielectric annealing, for producing SiNW FETs that exhibit high performance in terms of large on/off-state current ratio (-10s), low drain-induced barrier lowering (-30 mV) and low subthreshold swing (-80 mV/decade). The performance of inverter and ring-oscillator circuits fabricated from these nanowire FETs are also explored. The inverter demonstrates the highest voltage gain (-148) reported for a SiNW-based NOT gate, and the ring oscillator exhibits near rail-to-rail oscillation centered at 13.4 MHz. The static and dynamic characteristics of these NW devices indicate that these SiNW-based FET circuits are excellent candidates for various high-performance nanoelectronic applications.展开更多
文摘The previous report (XI) gave the electrochemical-potential theory of the Bipolar Field-Effect Transistors. This report (XII) gives the drift-diffusion theory. Both treat 1-gate and 2-gate, pure-base and impure-base, and thin and thick base. Both utilize the surface and bulk potentials as the parametric variables to couple the voltage and current equations. In the present drift-diffusion theory, the very many current terms are identified by their mobility multiplier for the components of drift current,and the diffusivity multiplier for the components of the diffusion current. Complete analytical driftdiffusion equations are presented to give the DC current-voltage characteristics of four common MOS transistor structures. The drift current consists of four terms: 1-D (One-Dimensional) bulk charge drift term, 1-D carrier space-charge drift term,l-D Ex^2 (transverse electric field) drift term,2-D drift term. The diffusion current consists of three terms: 1-D bulk charge diffusion term,l-D carrier space-charge diffusion term,and 2-D diffusion term. The 1-D Ex^2 drift term was missed by all the existing transistor theories, and contributes significantly, as much as 25 % of the total current when the base layer is nearly pure. The 2-D terms come from longitudinal gradient of the longitudinal electric field,which scales as the square of the Debye to Channel length ratio, at 25nm channel length with nearly pure base, (LD/L)^2 = 10^6 but with impurity concentration of 10^18cm^-3 , (LD/L)^2 = 10^-2 .
文摘This paper reports the DC steady-state voltage and current transfer characteristics and power dissipation of the Complimentary Metal-Oxide-Silicon (CMOS) voltage-inverter circuit using one physical Bipolar Field-Effect Transistor (BiFET) of nanometer dimensions. The electrical characteristics are numerically obtained by solving the five partial dif- ferential equations for the transistor structure of two MOS-gates on the two surfaces of a thin pure silicon base layer with electron and hole contacts on both ends of the thin base. Internal and CMOS boundary conditions are used on the three potentials (electrostatic and electron and hole electrochemical potentials). Families of curves are rapidly computed using a dual-processor personal computer running the 64-bit FORTRAN on the Windows XP operating system.
基金The authors acknowledge H. Ahmad and Y. -S. Shin for graphics assistance. This work was funded by the National Science Foundation under Grant CCF-0541461 and the Department of Energy (DE-FG02-04ER46175). D. Tham gratefully acknowledges support by the KAUST Scholar Award.
文摘We explore 10-nm wide Si nanowire (SiNW) field-effect transistors (FETs) for logic applications, via the fabrication and testing of SiNW-based ring oscillators. We report on SiNW surface treatments and dielectric annealing, for producing SiNW FETs that exhibit high performance in terms of large on/off-state current ratio (-10s), low drain-induced barrier lowering (-30 mV) and low subthreshold swing (-80 mV/decade). The performance of inverter and ring-oscillator circuits fabricated from these nanowire FETs are also explored. The inverter demonstrates the highest voltage gain (-148) reported for a SiNW-based NOT gate, and the ring oscillator exhibits near rail-to-rail oscillation centered at 13.4 MHz. The static and dynamic characteristics of these NW devices indicate that these SiNW-based FET circuits are excellent candidates for various high-performance nanoelectronic applications.