Title :
190-GHz fT, 130-GHz fmax SiGe HBTs with heavily doped base formed by HCl-free selective epitaxy
Author :
Kiyota, Yukihiro ; Hashimoto, Talcashi ; Udo, Tsutomu ; Kodama, Akihiro ; Shimamoto, Hiromi ; Hayami, Reiko ; Washio, Katsuyoshi
Author_Institution :
Central Res. Lab., Hitachi Ltd., Tokyo, Japan
Abstract :
A heavily-boron-doped SiGe base was formed by HCl-free selective epitaxial growth using LPCVD. This HCl-free growth enabled us to obtain high growth rate at low temperature and to suppress surface roughening of heavily-boron-doped SiGe. HBTs were fabricated with base regions with high boron concentration, i.e. 2.4 × 1020 cm-3. An accurately and appropriately designed boron profile produced HBTs with fT of 190 and fmax of 130 GHz. By modifying the impurity profiles in the intrinsic region, fT was increased above 200 GHz. These high-performance HBTs were implemented in a multiplexer and a demultiplexer, and resulted in faster than 50-Gb/s performance.
Keywords :
Ge-Si alloys; boron; chemical vapour deposition; doping profiles; heavily doped semiconductors; heterojunction bipolar transistors; millimetre wave bipolar transistors; semiconductor device measurement; semiconductor growth; surface topography; 190 GHz; 200 GHz; HCl-free selective epitaxy; LPCVD; SiGe HBTs; SiGe:B; boron profile; cutoff frequencies; demultiplexer; heavily doped base; high growth rate; intrinsic region; low temperature; maximum oscillation frequencies; multiplexer; surface roughening suppression; Boron; Cutoff frequency; Doping; Germanium silicon alloys; Heterojunction bipolar transistors; Rough surfaces; Silicon germanium; Surface morphology; Surface resistance; Surface roughness;
Conference_Titel :
Bipolar/BiCMOS Circuits and Technology Meeting, 2002. Proceedings of the 2002
Print_ISBN :
0-7803-7561-0
DOI :
10.1109/BIPOL.2002.1042904
