John D Cressler, Emmanuel F Crabe, et al.
IEDM 1991
The advances in the growth of pseudomorphic silicon-germanium epitaxial layers combined with the strong need for high-speed complementary circuits have led to increased interest in silicon-based heterojunction field-effect transistors. Metal-oxide-semiconductor field-effect transistors (MOSFET’s) with SiGe channels are guided by different design rules than state-of-the-art silicon MOSFET’s. The selection of the transistor gate material, the optimization of the silicon-germanium channel profile, the method of threshold voltage adjustment, and the silicon-cap and gate-oxide thickness sensitivities are the critical design parameters for the p-channel SiGe MOSFET. Two-dimensional numerical modeling demonstrates that n+ polysilicon-gate SiGe p-MOSFET’s have acceptable short-channel behavior at 0.20 µm channel lengths and are preferable to p+ polysilicon-gate p-MOSFET’s for 2.5 V operation. Experimental results of n+-gate modulation-doped SiGe p-MOSFET’s illustrate the importance of the optimization of the SiGe-channel profile. When a graded SiGe channel is used, hole mobilities as high as 220 cm2/V.s at 300 K and 980 cm2/V.s at 82 K are obtained. © 1994 IEEE.
John D Cressler, Emmanuel F Crabe, et al.
IEDM 1991
Bernard S. Meyerson, Franz J. Himpsel, et al.
Applied Physics Letters
Maurizio Arienzo, James H. Comfort, et al.
ESSDERC 1992
Suraj J. Mathew, Guofu Niu, et al.
IEEE Electron Device Letters