Journal of Vacuum Science & Technology A, Vol.24, No.3, 831-834, 2006
Temperature effects in complementary metal-oxide semiconductor microwave distributed amplifiers
Broadband amplifiers implemented in complementary metal-oxide semiconductor technology offer a low-cost solution as gain elements for wideband communication systems. These components must maintain an acceptable target performance for a wide range of temperatures. We present experimental results for the gain, reflection coefficients, and group delay of a broadband amplifier operating from 2 to 14 GHz in the temperature range of 25 - 125 degrees C. the high-frequency power gain drops-by approximately 0.37 dB every 10 degrees C of temperature increase, the maximum input and koutput refection coefficients change by less than 0.1 dB/10 degrees C, and the change in the input-to-output group delay is negligible over the measured temperature range. The amplifier was simulated using temperature-dependent measurement-based models for the transistors, capacitors, and resistors and a single-temperature electromagnetic-simulation-based model for the inductors and interconnections. Simulated gain degradation is 0.22 dB/10 degrees C, which suggests that the temperature effects on the inductors and interconnections lines are very important; however, temperature-dependent simulation is not a standard feature of electromagnetic (EM) simulators. It is thus important to include temperature effects when developing, models based on EM simulations. Our results suggest that the key element to be considered is the conductor's resistivity increase with temperature. (c) 2006 American Vacuum Society.