Investigation of Enhanced Impact Ionization in Uniaxially Strained Si n-Channel Metal Oxide Semiconductor Field Effect Transistor

Abstract

The impact ionization rate in uniaxially strained silicon is evaluated from viewpoints of the ionization threshold β and maximum electric field E m for the first time. Strain and temperature dependences of β are investigated on the basis of the change in slope in a universal relation while E m, which is also dependent on strain and temperature, is investigated on the basis of the change in saturation voltage V DSAT. The impact ionization rate is a function of β and E m such that we also evaluated strain and temperature dependence of multiplication factor M - 1 (= I sub/I D) to determine the major concern of change in impact ionization rate. The result shows that the change in E m due to the change in potential drop along the channel is the major concern in a uniaxially strained silicon n-channel metal oxide semiconductor field effect transistor (nMOSFET).

High-Frequency Capacitance–Voltage Characteristics of N-Type Metal–Oxide–Semiconductor Capacitor Based on Strained-Si/SiGe Architecture

“…Such challenges have impelled researchers to find various alternatives and, as a result, a strained-Si/SiGe (SSi/SiGe) material system has emerged. [1][2][3][4][5][6] By introducing strain into Si, the carrier mobility can be enhanced and the band gap can be modified. [7][8][9][10] However, owing to type II band offsets, carries can be confined at different interfaces, degrading the capacitance-voltage (C-V ) characteristics of the material system.…”

Conduction Band Model of [110]/(001) Uniaxially Strained Si

“…The conduction band of Si material is changed and its electron mobility is also enhanced under [110]/(001) uniaxial stress. [1][2][3][4] This can greatly improve the performance of the n-type Si metal oxide semiconductor field effect transistor (nMOSFET), [5][6][7][8][9][10] and has been widely applied in small-scale devices and very large-scale integration (VLSI). [11][12][13][14][15][16] However, theoretical research has fallen behind practical applications.…”