Structure optimization of trench-isolated SiGe HBTs for simultaneous improvements in thermal and electrical performances

The current level in the modern high-speed SiGe heterojunction bipolar transistors (HBTs) continues to increase for operation speed enhancement, but the resultant self-heating and elevated junction temperature emerge as a growing concern for device reliability as well as performance. To address such thermal issues, the optimization of SiGe HBT structures to achieve simultaneous improvements in thermal and electrical performance is carried out in this study. As a foundation for the study, an R/sub th/ measurement method and a geometry-based fast analytic thermal model were first developed for trench-isolated SiGe HBTs. Based on the method and model, a set of device design points for lowered R/sub th/ without compromising the RF performance have been successfully proposed and experimentally verified on IBM's 200-GHz SiGe HBTs. The details of the proposed structures and acquired results will be described in detail in the paper. The results obtained in this study shed a light on the possibility of the simultaneous optimization of thermal and electrical performance of SiGe HBTs.

[1]  David Blaauw,et al.  Gate oxide leakage current analysis and reduction for VLSI circuits , 2004, IEEE Transactions on Very Large Scale Integration (VLSI) Systems.

[2]  A. Gupta,et al.  CW measurement of HBT thermal resistance , 1992 .

[3]  D. J. Walkey,et al.  Simultaneous extraction of thermal and emitter series resistances in bipolar transistors , 1997, Proceedings of the 1997 Bipolar/BiCMOS Circuits and Technology Meeting.

[4]  Wen-Chau Liu,et al.  Measurement of junction temperature of an AlGaAs/GaAs heterojunction bipolar transistor operating at large power densities , 1995 .

[5]  T. Vanhoucke,et al.  Revised method for extraction of the thermal resistance applied to bulk and SOI SiGe HBTs , 2004, IEEE Electron Device Letters.

[6]  D. J. Walkey,et al.  A scalable thermal model for trench isolated bipolar devices , 2000 .

[7]  Basanth Jagannathan,et al.  Performance and design considerations for high speed SiGe HBTs of f/sub T//f/sub max/=375 GHz/210 GHz , 2003, International Conference onIndium Phosphide and Related Materials, 2003..

[8]  E. S. Schlig,et al.  Thermal properties of very fast transistors , 1970 .

[9]  J. Rieh,et al.  Structural dependence of the thermal resistance of trench-isolated bipolar transistors , 2002, Proceedings of the Bipolar/BiCMOS Circuits and Technology Meeting.

[10]  E. Zanoni,et al.  A simple method for the thermal resistance measurement of AlGaAs/GaAs heterojunction bipolar transistors , 1998 .

[11]  J. Laskar,et al.  A low-power ka-band Voltage-controlled oscillator implemented in 200-GHz SiGe HBT technology , 2005, IEEE Transactions on Microwave Theory and Techniques.

[12]  P. Palestri,et al.  Compact modeling of thermal resistance in bipolar transistors on bulk and SOI substrates , 2002 .

[13]  B. Jagannathan,et al.  Measurement and modeling of thermal resistance of high speed SiGe heterojunction bipolar transistors , 2001, 2001 Topical Meeting on Silicon Monolithic Integrated Circuits in RF Systems. Digest of Papers (IEEE Cat. No.01EX496).

[14]  M. Schroter,et al.  Modeling thermal resistance in trench-isolated bipolar technologies including trench heat flow , 2002 .

[16]  D. J. Walkey,et al.  Prediction of thermal resistance in trench isolated bipolar device structures , 1998, Proceedings of the 1998 Bipolar/BiCMOS Circuits and Technology Meeting (Cat. No.98CH36198).

[17]  S. P. Marsh,et al.  Direct extraction technique to derive the junction temperature of HBT's under high self-heating bias conditions , 2000 .

[18]  S. Narendra,et al.  Full-chip subthreshold leakage power prediction and reduction techniques for sub-0.18-/spl mu/m CMOS , 2004, IEEE Journal of Solid-State Circuits.

[19]  M. G. Adlerstein,et al.  Thermal resistance measurements for AlGaAs/GaAs heterojunction bipolar transistors , 1991 .

[20]  M. Pfost,et al.  A practical method to extract the thermal resistance for heterojunction bipolar transistors , 2003, ESSDERC '03. 33rd Conference on European Solid-State Device Research, 2003..

[21]  Wen-Chau Liu,et al.  Thermal coupling in 2-finger heterojunction bipolar transistors , 1995 .

[22]  C. G. Englefield,et al.  Electrical measurement of the junction temperature of an RF power transistor , 1992 .

[23]  Peter M. Asbeck,et al.  Determination of junction temperature in AlGaAs/GaAs heterojunction bipolar transistors by electrical measurement , 1992 .

[24]  A.P. Chandrakasan,et al.  A 175 mV multiply-accumulate unit using an adaptive supply voltage and body bias (ASB) architecture , 2002, 2002 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.02CH37315).

[25]  S. Jeng,et al.  Self-aligned SiGe NPN transistors with 285 GHz f/sub MAX/ and 207 GHz f/sub T/ in a manufacturable technology , 2002, IEEE Electron Device Letters.