Title :
High performance 0.25 μm p-type Ge-SiGe MODFETs
Author :
Höck, G. ; Hackbarth, T. ; Erben, U. ; Kohn, E. ; König, U.
Author_Institution :
Dept. of Electron Devices & Ciruits, Ulm Univ., Germany
fDate :
9/17/1998 12:00:00 AM
Abstract :
The authors report the fabrication and characterisation of 0.25 μm gate length p-type Ge channel modulation doped field effect transistors (MODFETs) with improved RF performance. The structure consists of a compressively strained pure Ge hole channel, grown on a relaxed 5 μm thick graded Si0.4Ge0.6 buffer. A room temperature hole mobility of 1870 cm2/Vs and a sheet carrier density of 2.1×1012 cm-2 were measured. The devices exhibit DC transconductances up to 160 mS/mm and saturation currents up to 300 mA/mm. Cutoff frequencies of fT=32 GHz and fmax=85 GHz have been achieved
Keywords :
Ge-Si alloys; carrier density; elemental semiconductors; germanium; high electron mobility transistors; hole mobility; millimetre wave field effect transistors; semiconductor materials; 0.25 micron; 160 mS/mm; 32 GHz; 85 GHz; DC transconductances; Ge-SiGe; Ge/SiGe MODFETs; RF performance improvement; Si0.4Ge0.6; characterisation; compressively strained pure Ge hole channel; fabrication; graded Si0.4Ge0.6 buffer; modulation doped field effect transistors; p-type Ge channel; room temperature hole mobility; saturation currents; sheet carrier density;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19981284
