总电离剂量辐射电荷对沟槽型功率MOSFET电容的调制

This article investigates the modulation of total ionizing dose (TID) radiation charge on the capacitance of trench power MOSFET. A radiation charge modulated capacitance model is proposed to effectively characterize the degradation of input ( C_ iss ) and output capacitance ( C_ oss ) under TID radiation. The mechanism of TID-induced capacitance degradation is revealed. At low drain voltage ( V_D ) , the gate–drain capacitance ( C_ gd ) and drain–source capacitance ( C_ ds ) increase after irradiation, while the gate–source capacitance ( C_ gs ) decreases. C_ gd and C_ ds are almost unchanged at high drain voltage, and C_ gs remains to decrease. The radiation charge equivalently modulates the doping concentration in the silicon layer, which alters the depletion width and leads to capacitance variation. The proposed model fits well with both experimental and simulation results. Measured gate charge results indicate that gate–drain charge ( Q_ gd ) increases and gate–source ( Q_ gs ) decreases after irradiation, providing further support for mechanistic explanations.