Title :
Bidirectional bistability in n-p-n Si/Si/sub 1-x/Ge/sub x//Si structures
Author :
Shen, G.D. ; Xu, D.X. ; Willander, M. ; Hannson, G.V. ; Svensson, C.
Author_Institution :
Dept. of Phys. & Meas. Technol., Linkoping Univ., Sweden
Abstract :
Several structures of n-Si/p-Si/sub 1-x/Ge/sub x//n-Si double heterojunction bipolar transistors (DHBTs) with strained thin base, fabricated by molecular beam epitaxy (MBE), are described. Negative differential resistance (NDR) phenomena-a strong and symmetric bidirectional bistability modulated by base bias, together with a multistep characteristic in collector current versus emitter-collector bias voltage in the devices with very thin base-were observed at room temperature. The physical origins are analyzed. The results are compared with the characteristics of n-Ga/sub 1-x/A1/sub x/As/p-GaAs/n-GaAs single HBTs (SHBTs).<>
Keywords :
bipolar transistors; elemental semiconductors; germanium; molecular beam epitaxial growth; negative resistance effects; semiconductor junctions; semiconductor materials; silicon; DHBTs; MBE; NDR; Si-Si/sub 1-x/Ge/sub x/-Si; base bias; collector current; double heterojunction bipolar transistors; emitter-collector bias voltage; molecular beam epitaxy; multistep characteristic; n-p-n transistors; negative differential resistance; physical origins; room temperature; strained thin base; symmetric bidirectional bistability; very thin base; Doping; Electrical resistance measurement; Fabrication; Gallium arsenide; Low voltage; Molecular beam epitaxial growth; Plasma measurements; Substrates; Vacuum systems; Wet etching;
Journal_Title :
Electron Device Letters, IEEE
