Impact of channel orientation on ballistic current of nDGFETs with alternative channel materials

Abstract

Alternative channels materials (like GaAs, Ge, …) are expected to lead to improved current drive capability in MOSFETs devices operating in the quasi ballistic regime. In this work, the previously predicted in-plane isotropy of ballistic drain current in double gate nMOSFETs on (0 0 1) and (1 1 1) in all zinc-blend semiconductor substrates, has been rigorously demonstrated on the basis of a generalized Natori model. Moreover, the anisotropy on (1 1 0) substrate has been further investigated, showing and explaining that, as already reported for Ge only [Low Tony, Hou YT, Li MF, Zhu Chunxiang, Chin Albert, Samudra1 G, et al. Investigation of performance limits of germanium double-gated MOSFETs. IEDM Tech Dig 2003:961–4], the best ballistic current of GaAs, InAs and InSb nDGFETs is also obtained on this surface, for channels aligned in the [ 1 1 ¯ 0 ] direction, opening new perspectives in quasi ballistic device optimization with alternative channel material.