Title :
The Analysis of Power and Linearity Characteristics of SiGe HBTs at Low Temperatures
Author :
Hsieh, Meng-Wei ; Hsin, Yue-Ming ; Liang, Kung-Hao ; Chan, Yi-Jen ; Tang, Denny ; Lee, Chwan-Ying
Author_Institution :
Dept. of Electr. Eng., Nat. Central Univ., Chungli
Abstract :
This work investigates the temperature dependence, from 300K to 77K, of the output power, PAE, and linearity for SiGe HBTs with and without SIC. The NADC pi/4DQPSK signal is used to analyze the linearity of SiGe HBTs. For device without SIC, the heterojunction barrier effect becomes more propound, which seriously reduces the current gain and cutoff frequency at cryogenic temperatures. The output power, PAE and linearity at 2.4 GHz decrease conspicuously with decreasing operation temperatures. This barrier effect can be negligible in SiGe HBT with SIC and thus the device achieves better power and linearity performance at cryogenic temperatures
Keywords :
Ge-Si alloys; cryogenic electronics; differential phase shift keying; heterojunction bipolar transistors; low-temperature techniques; microwave bipolar transistors; semiconductor device models; 2.4 GHz; 4DQPSK signal; 77 to 300 K; HBT linearity; SiGe; cryogenic temperature; heterojunction barrier effect; linearity characteristics; power characteristics; temperature dependence; Cryogenics; Cutoff frequency; Germanium silicon alloys; Heterojunctions; Linearity; Power generation; Signal analysis; Silicon carbide; Silicon germanium; Temperature dependence; SIC; cryogenic temperatures; heterojunction barrier effect; linearity; power;
Conference_Titel :
Microwave Symposium Digest, 2006. IEEE MTT-S International
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-9541-7
Electronic_ISBN :
0149-645X
DOI :
10.1109/MWSYM.2006.249857
