Degeneration of CMOS power cells after hot-carrier and load mismatch stresses

In this letter, we investigate the performance degradation of nMOS transistors due to hot-carrier effect and load impedance mismatch. The dc and radio-frequency characteristics, such as drain current, threshold voltage, transconductance, output power, power-added efficiency, etc., are affected under hot-carrier effect. With load impedance mismatch, the transistors experience the reflected power from load and increase the energy of hot carriers. This effect will make dc and power performances degenerate heavily. In this letter, device characteristics were measured at 5.2 GHz.