Title :
A semi-empirical model for the field-effect mobility of hydrogenated polycrystalline-silicon MOSFETs
Author :
Seki, Shunji ; Kogure, Osamu ; Tsujiyama, Bunjiro
Author_Institution :
Opto-Electron. Labs., NTT Corp., Kanagawa, Japan
fDate :
5/1/1988 12:00:00 AM
Abstract :
The quantitative relationship between field-effect mobility (μ FE) and grain-boundary trap-state density (Nt ) in hydrogenated polycrystalline-silicon (poly-Si) MOSFETs is investigated. The focus is on the field-effect mobility in MOSFETs with Nt 1×102 cm-2. It is found that reducing Nt to as low as 5×1011 cm-2 has a great impact on μFE. MOSFETs with the Nt of 4.2×1011 cm-2 show an electron mobility of 185 cm2/V-s, despite a mean grain size of 0.5 μm. The three principal factors that determine μFE, namely, the low-field mobility, the mobility degradation factor, and the trap-state density Nt are clarified
Keywords :
carrier mobility; defect electron energy states; elemental semiconductors; insulated gate field effect transistors; semiconductor device models; silicon; electron mobility; field-effect mobility; grain size; grain-boundary trap-state density; low-field mobility; mobility degradation factor; polycrystalline Si:H; polysilicon MOSFETs; semiempirical model; Degradation; Electric variables; Electron mobility; Electron traps; Grain boundaries; Grain size; MOSFETs; Semiconductor films; Silicon; Three-dimensional integrated circuits;
Journal_Title :
Electron Devices, IEEE Transactions on
