Title :
Strain-controlled Si-Ge modulation-doped FET with ultrahigh hole mobility
Author :
Murakami, E. ; Nakagawa, K. ; Nishida, A. ; Miyao, M.
Author_Institution :
Hitachi Ltd., Tokyo, Japan
Abstract :
A novel modulation-doped field effect transistor (MODFET) with a strain-controlled Ge channel, p-Si/sub 0.5/Ge/sub 0.5//Ge/Si/sub 1-x/Ge/sub x/, is fabricated by molecular beam epitaxy (MBE). In order to enlarge the valence-band discontinuity, strain at the p-Si/sub 0.5/Ge/sub 0.5//Ge interface is controlled by changing the composition of the relaxed Si/sub 1-x/Ge/sub x/ layer. For this MODFET operated at around 77 K, an ultrahigh-field-effect mobility of approximately 9000 cm/sup 2//V-s is obtained.<>
Keywords :
Ge-Si alloys; high electron mobility transistors; semiconductor junctions; semiconductor materials; 77 K; HEMT; MBE; MODFET; Si/sub 0.5/Ge/sub 0.5/-Ge-Si/sub 1-x/Ge/sub x/; modulation-doped field effect transistor; molecular beam epitaxy; relaxed Si/sub 1-x/Ge/sub x/ layer; strain-controlled Ge channel; ultrahigh hole mobility; Buffer layers; Capacitive sensors; Epitaxial layers; FETs; HEMTs; MODFETs; Molecular beam epitaxial growth; Plasma temperature; Strain control; Substrates;
Journal_Title :
Electron Device Letters, IEEE
