Title :
A Si/SiGe heterojunction bipolar transistor with undoped SiGe spacer for CRYO-BiCMOS circuits
Author :
Yamazaki, T. ; Imai, K. ; Tashiro, T. ; Tatsumi, T. ; Niino, T. ; Nakamae, M.
Author_Institution :
NEC Corp., Kanagawa, Japan
Abstract :
A heterojunction bipolar transistor (HBT) for BiCMOS circuits is described which can operate at liquid nitrogen (LN2) temperature (CRYO-BiCMOS). An HBT which has an n/sup +/-polysilicon/n-type Si epitaxial layer emitter structure on an undoped SiGe/p/sup +/ SiGe base structure, with both SiGe layers having a Ge fraction of 30%, has been developed to maintain the current gain and to reduce the emitter-base turn-on voltage at LN2 temperature. This HBT achieves a high current gain of 124 and a low turn-on voltage of 0.96 V at LN2 temperature. Under the conditions of 3.3 V supply voltage and 83 K, a 0.6 mu m CRYO-BiCMOS two-input NAND gate shows a basic gate delay of 200 ps.<>
Keywords :
BIMOS integrated circuits; Ge-Si alloys; cryogenics; elemental semiconductors; heterojunction bipolar transistors; semiconductor materials; silicon; 0.6 micron; 0.96 V; 200 ps; 3.3 V; 77 K; 83 K; CRYO-BiCMOS circuits; HBT; emitter structure; emitter-base turn-on voltage; gate delay; heterojunction bipolar transistor; liquid nitrogen; monolithic IC; n/sup +/-polysilicon/n-type Si epitaxial layer; two-input NAND gate; undoped SiGe spacer; BiCMOS integrated circuits; Delay; Epitaxial layers; Germanium silicon alloys; Heterojunction bipolar transistors; Low voltage; Nitrogen; Silicon germanium; Temperature;
Conference_Titel :
Electron Devices Meeting, 1990. IEDM '90. Technical Digest., International
Conference_Location :
San Francisco, CA, USA
DOI :
10.1109/IEDM.1990.237152
