Title :
High-transconductance n-type Si/SiGe modulation-doped field-effect transistors
Author :
Ismail, K. ; Meyerson, B.S. ; Rishton, S. ; Chu, J. ; Nelson, S. ; Nocera, J.
Author_Institution :
IBM T.J. Watson Res. Center, Yorktown Heights, NY, USA
fDate :
5/1/1992 12:00:00 AM
Abstract :
The authors report on the fabrication and the resultant device characteristics of the first 0.25- mu m gate-length field-effect transistor based on n-type modulation-doped Si/SiGe. Prepared using ultrahigh vacuum/chemical vapor deposition (UHV/CVD), the mobility and electron sheet charge density in the strained Si channel are 1500 (9500) cm/sup 2//V-s and 2.5*10/sup 12/ (1.5*10/sup 12/) cm/sup -2/ at 300 K (77 K). At 77 K, the devices have a current and transconductance of 325 mA/mm and 600 mS/mm, respectively. These values far exceed those found in Si MESFETs and are comparable to the best results achieved in GaAs/AlGaAs modulation-doped transistors.<>
Keywords :
Ge-Si alloys; carrier mobility; chemical vapour deposition; elemental semiconductors; high electron mobility transistors; semiconductor materials; silicon; 0.25 micron; 600 mS; CVD; MODFET; Si-GeSi; UHV; chemical vapor deposition; electron sheet charge density; fabrication; field-effect transistors; mobility; modulation-doped; n-type; strained Si channel; submicron gate length; transconductance; ultrahigh vacuum; Chemical vapor deposition; Electron mobility; Epitaxial layers; FETs; Fabrication; Gallium arsenide; Germanium silicon alloys; MESFETs; Silicon germanium; Transconductance;
Journal_Title :
Electron Device Letters, IEEE
