Title :
Numerical analysis of island-edge effects in SOS MOSFETs
Author :
Lu, Quan ; Chang Huang
Author_Institution :
Shaanxi Microelectron. Res. Inst., Shaanxi, China
Abstract :
Degradation of electric characteristics of SOS MOSFETs occurs due to a parasitic transistor in the islands edge. When SOS devices are fabricated with a wet etch process, the island-edge effects are caused by high interface-state densities in the ⟨111⟩ sloping edge and field concentrations near the edge. However, although a nearly vertical island-edge can be obtained by a dry etch process, there still remains field concentration and some damage at the Si-SiO2 interface. Numerical simulation results on the parasitic transistors in the ⟨111⟩ sloping island edge and in the vertical island edge are reported. The effective width and threshold voltage of the parasitic edge transistors were obtained by two-dimensional simulation, and edge-effects on subthreshold characteristics in SOS MOSFETs were studied. The simulation results showed good agreement with experiment
Keywords :
field effect integrated circuits; insulated gate field effect transistors; numerical analysis; semiconductor device models; SOS MOSFETs; Si-SiO2 interface; dry etch process; edge-effects; effective width; electric characteristics degradation; field concentrations; high interface-state densities; island-edge effects; numerical analysis; parasitic transistor; parasitic transistors; simulation results; sloping edge; sloping island edge; subthreshold characteristics; threshold voltage; two-dimensional simulation; vertical island edge; wet etch process; Computational modeling; Distributed computing; Finite difference methods; Interface states; MOSFET circuits; Numerical analysis; Numerical simulation; Plasma applications; Threshold voltage; Wet etching;
Conference_Titel :
SOS/SOI Technology Workshop, 1988. Proceedings., 1988 IEEE
Conference_Location :
St. Simons Island, GA
DOI :
10.1109/SOI.1988.95405
