A high efficiency Si-CMOS power amplifier for 60 GHz band broadband wireless communication employing optimized transistor size

For small size and low cost mobile terminals on millimeter wave radio communication, we design and fabricate 60 GHz-band broadband power amplifier (PA) using a 90 nm silicon complementary metal oxide semiconductor (Si-CMOS) process. In designing high linear gain PA, transistor size optimization method of PA is used. Target output power is 7 dBm in single-end and 10 dBm in push-pull structure. With the transistor size optimization method, unit gate width is 2 μm and a number of gate fingers is 32, so total optimal gate width is 64 μm. We fabricate the single-end PA and push-pull PA designed with this transistor size. The single-end PA has achieved 1 dB compression output power P_1dB of 7.3 dBm, saturation power P_sat of 10.2 dBm, linear gain G_L, of 10.9 dB, peak power added efficiency PAE of 21.3% at 63 GHz, and a bandwidth over 7 dBm of 9 GHz. The push-pull PA has achieved P_1dB of 10.2 dBm, P_sat of 12.9 dBm, G_L of 13.1 dB, peak PAE of 25.4% at 63 GHz, and a bandwidth over 10 dBm of 10 GHz. These measurement results show the potentiality of high efficiency Si-CMOS PA for 60 GHz band broadband wireless communication applications.