Power performance of 65 nm CMOS integrated LDMOS transistors at WLAN and X-band frequencies

Abstract

Laterally diffused metal oxide semiconductor (LDMOS) transistors with 10 V breakdown voltage have been implemented in a 65 nm Complementary metal oxide semiconductor (CMOS) process without extra masks or process steps. Radio frequency (RF) performance for Wireless local area network (WLAN) frequencies and in X-band at 8 GHz is investigated by load-pull measurements in class AB operation for both 3.3 and 5 V supply voltage. Results at 2.45 GHz showed 290 mW/mm output power density with 17 dB linear gain and over 45% power added efficiency (PAE) at 4 dB compression at a supply voltage of 5 V. Furthermore, results in X-band at 8 GHz show 8 dB linear gain, 320 mW/mm output power density and over 22% PAE at 4 dB compression. Third-order intermodulation measurements at 8 GHz revealed OIP3 of 18.9 and 21.9 dBm at 3.3 and 5 V, respectively. The transistors were also tested for reliability which showed no drift in quiescent current after 26 h of DC stress while high-power RF stress showed only small extrapolated drift at 10 years in output power density. This is to the authors' knowledge the first time high output power density in X-band is demonstrated for integrated LDMOS transistors manufactured in a 65 nm CMOS process without extra process steps.