Title :
Carbon effect on neutral base recombination in high-speed SiGeC HBTs
Author :
Barbalat, B. ; Schwartzmann, Thierry ; Chevalier, P. ; Vandelle, B. ; Rubaldo, L. ; Saguin, F. ; Zerounian, N. ; Aniel, F. ; Chantre, Alain
Author_Institution :
STMicroelectron., Crolles
Abstract :
We have presented the performances and electrical behavior of high-speed SiGeC HBTs having enhanced NBR by carbon insertion in excess. The current gain is strongly reduced, so that BVCEO increases by 0.5 V, and the fT times BVCEO product shifts from 340 to 423 GHz.V, which offers new possibilities for HBTs optimization, notably by increasing collector doping. Thanks to the NBR, the current gain dependency with temperature above 300 K is reduced, which is interesting for applications such as power amplifiers. The current gain evolution with VBE is explained by trap saturation, which was confirmed in simulations by inserting a trap level in the base gap. The band gap dependency with carbon insertion is also demonstrated and was developed in the final paper
Keywords :
Ge-Si alloys; carbon; electron-hole recombination; energy gap; heterojunction bipolar transistors; semiconductor doping; HBT optimization; NBR; SiGeC; band gap dependency; carbon effect; carbon insertion; collector doping; current gain evolution; high-speed HBT; neutral base recombination; trap saturation; Annealing; Boron; Carbon dioxide; Charge carrier lifetime; Degradation; Germanium silicon alloys; Heterojunction bipolar transistors; Silicon germanium; Temperature measurement; Voltage;
Conference_Titel :
SiGe Technology and Device Meeting, 2006. ISTDM 2006. Third International
Conference_Location :
Princeton, NJ
Print_ISBN :
1-4244-0461-4
DOI :
10.1109/ISTDM.2006.246546
