Linearity and power characteristics of SiGe HBTs at high temperatures for RF applications

In this paper, the power gain, power-added efficiency (PAE) and linearity of power SiGe heterojunction-bipolar transistors at various temperatures have been presented. The power characteristics were measured using a two-tone load-pull system. For transistors biased with fixed base voltage, the small-signal power gain and PAE of the devices increase with increasing temperature at low base voltages, while they decrease at high base voltages. Besides, the linearity is improved at high temperature for all voltage biases. However, for devices with fixed collector current, the small-signal power gain, PAE, and linearity are nearly unchanged with temperature. The temperature dependence of power and linearity characteristics can be understood by analyzing the cutoff frequency, the collector current, Kirk effect and nonlinearities of transconductance at different temperatures.

[1]  P. M. Asbeck,et al.  Linearity characteristics of GaAs HBTs and the influence of collector design , 2000 .

[2]  M. Soyuer,et al.  SiGe power HBT's for low-voltage, high-performance RF applications , 1998, IEEE Electron Device Letters.

[3]  A. Anwar,et al.  Temperature dependence of intermodulation and linearity in GaN based devices , 2001, 2001 IEEE MTT-S International Microwave Sympsoium Digest (Cat. No.01CH37157).

[4]  Zhenqiang Ma,et al.  A high-power and high-gain X-band Si/SiGe/Si heterojunction bipolar transistor , 2002 .

[5]  H. Morkoc,et al.  Heterojunction bipolar transistor design for power applications , 1992 .

[6]  S. Jeng,et al.  SiGe HBTs with cut-off frequency of 350 GHz , 2002, Digest. International Electron Devices Meeting,.

[7]  K. Washio.  SiGe HBT and BiCMOS technologies , 2003, IEEE International Electron Devices Meeting 2003.

[8]  L. Larson,et al.  An X-band monolithic active mixer in SiGe HBT technology , 1996, 1996 IEEE MTT-S International Microwave Symposium Digest.

[9]  M. Dunn,et al.  Pulsed measurements and modeling for electro-thermal effects , 1996, Proceedings of the 1996 BIPOLAR/BiCMOS Circuits and Technology Meeting.

[10]  J. Comfort,et al.  Low temperature operation of Si and SiGe bipolar transistors , 1990, International Technical Digest on Electron Devices.

[11]  K. Jenkins,et al.  Profile scaling constraints for ion-implanted and epitaxial bipolar technology designed for 77 K operation , 1991, International Electron Devices Meeting 1991 [Technical Digest].

[12]  BASE TRANSPORT IN NEAR-IDEAL GRADED-BASE Si/Si,-,Ge,/Si HETEROJUNCTION BIPOLAR TRANSISTORS FROM 150 K TO 370 K , 1990 .

[13]  D. Pavlidis,et al.  Large-signal modeling and study of power saturation mechanisms in heterojunction bipolar transistors , 1991, 1991 IEEE MTT-S International Microwave Symposium Digest.

[14]  John D. Cressler,et al.  RF linearity characteristics of SiGe HBTs , 2001 .

[16]  Lawrence E. Larson,et al.  A theory of high-frequency distortion in bipolar transistors , 2003 .

[17]  H. Schumacher,et al.  Class-A SiGe HBT power amplifiers at C-band frequencies , 1995, IEEE Microwave and Guided Wave Letters.

[18]  Liang-Hung Lu,et al.  X- and Ku-band amplifiers based on Si/SiGe HBT's and micromachined lumped components , 1998 .

[19]  Guo-Wei Huang,et al.  Temperature effect on power characteristics of SiGe HBTs , 2004, 2004 IEEE MTT-S International Microwave Symposium Digest (IEEE Cat. No.04CH37535).