3.9 ps SiGe HBT ECL ring oscillator and transistor design for minimum gate delay

We show empirical results that demonstrate the effect of high performance SiGe HBT design parameters on the minimum gate delay of an ECL ring oscillator. SiGe HBT devices with a high f/sub MAX/ (338 GHz) and a low f/sub T/ (180 GHz) achieve a minimum delay of 3.9 ps, which to our knowledge is the lowest reported delay for a silicon based logic gate. Compared to the extracted (extrapolated) f/sub T/ and f/sub MAX/, a simple figure of merit proportional to /spl radic/f/sub T//R/sub B/C/sub CB/ with R/sub B/ and C/sub CB/ extracted from S-parameter measurement is best correlated to the minimum gate delay.

[1]  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.

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

[3]  R. A. Gosser,et al.  New bipolar figure of merit "fo" , 2002, Proceedings of the Bipolar/BiCMOS Circuits and Technology Meeting.

[4]  M. Sokolich,et al.  Demonstration of sub-5 ps CML ring oscillator gate delay with reduced parasitic AlInAs/InGaAs HBT , 2001, IEEE Electron Device Letters.

[5]  B. Jagannathan,et al.  A 0.18 /spl mu/m 90 GHz f/sub T/ SiGe HBT BiCMOS, ASIC-compatible, copper interconnect technology for RF and microwave applications , 1999, International Electron Devices Meeting 1999. Technical Digest (Cat. No.99CH36318).

[6]  J. Bock,et al.  Sub 5 ps SiGe bipolar technology , 2002, Digest. International Electron Devices Meeting,.

[8]  J. Bock,et al.  High-speed SiGe:C bipolar technology , 2001, International Electron Devices Meeting. Technical Digest (Cat. No.01CH37224).

[9]  Katsuyoshi Washio,et al.  A 0.2-/spl mu/m self-aligned selective-epitaxial-growth SiGe HBT featuring 107-GHz f/sub max/ and 6.7-ps ECL , 2001 .

[10]  Johannes M. C. Stork.  Bipolar transistor scaling for minimum switching delay and energy dissipation , 1988, Technical Digest., International Electron Devices Meeting.

[11]  K. Oda,et al.  5.3-ps ECL and 71-GHz static frequency divider in self-aligned SEG SiGe HBT , 2001, Proceedings of the 2001 BIPOLAR/BiCMOS Circuits and Technology Meeting (Cat. No.01CH37212).

[12]  B. Jagannathan,et al.  A 4.2-ps ECL ring-oscillator in a 285-GHz f/sub MAX/ SiGe technology , 2002, IEEE Electron Device Letters.