Switch-OFF Avalanche-Breakdown-Induced Electrical Degradations of RF-LDMOS Transistor for SMPAs Applications

Abstract

The electrical parameters degradations of a radio frequency lateral-diffused metal–oxide–semiconductor transistor under switch-OFF avalanche breakdown stress have been first experimentally investigated. A modified three-port dc-IV method is proposed to demonstrate the degradation mechanisms. It shows that the interface states generation under the edge of the polygate at the n-drift region brings the increase in ON-resistance due to the decrease in carrier mobility, while the hot-holes injection and trapping there leads to the increase in gate–drain capacitance due to the widening restriction of the depletion layer in the n-drift region. Furthermore, the output power and the power gain are also decreased under the avalanche shocks. However, other electrical parameters, such as threshold voltage, gate–source capacitance, and drain–source capacitance, can be kept unchanged.