Author_Institution :
IBM Thomas J. Watson Res. Center, Yorktown Heights, NY, USA
Abstract :
For pt.I see ibid., vol.38, no.3, p.634-49, March 1991. MOSFETs with channel lengths smaller than 0.25 μm with substrates of four different semiconductors and one alloy of the diamond and zinc-blende structures (n-channel Ge, Si, GaAs, InP, In0.53Ga0.47 As, and p-channel Si) were simulated at 77 and 300 K with a self-consistent two-dimensional Monte Carlo program. With the exception of the In-based materials, the speed of the devices appears to be largely independent of the semiconductor. This universal behavior results from the similarity among the medium-energy-scale features of the band structures of the cubic semiconductors. Low-energy concepts, such as mobility and effective mass, fail to describe charge transport as carriers populate a larger fraction of the Brillouin zone in these small devices driven at reasonably high biases. The assumptions made, the approximations used, and, in particular, the meaning of the words speed and reasonably mentioned above are discussed
Keywords :
Monte Carlo methods; insulated gate field effect transistors; semiconductor device models; semiconductors; 0.25 micron; 300 K; 77 K; Brillouin zone; GaAs; Ge; In0.53Ga0.47As; InP; Monte Carlo simulation; Si; approximations; assumptions; band structures; charge transport; cubic semiconductors; diamond structure; effective mass; medium-energy-scale features; mobility; small devices; submicron MOSFET; technologically significant semiconductors; two-dimensional Monte Carlo program; zinc-blende structures; Effective mass; Gallium alloys; Gallium arsenide; Germanium alloys; Indium phosphide; MOSFETs; Monte Carlo methods; Semiconductor materials; Silicon alloys; Substrates;
