耗散功率与环境温度对功率VDMOS热阻的影响分析

运用电学测试法，以两款不同封装类型功率VDMOS为实验对象，考察了耗散功率和环境温度对器件稳态热阻值的影响。结果表明：器件热阻值不是一个恒定不变的常量，由于电流拥挤效应，材料导热系数等条件的改变，它会随耗散功率及环境温度的增大而增大。该研究加深了对功率器件热阻理论的认识，为功率VDMOS的热特性评估提供了可靠的依据。

The Influence of Power dissipation and Air environment on Thermal resistance of Power VDMOS

Two types of power VDMOS devices are taken as an example, the electrical method is employed to analyze the influence of power dissipation and air environment on steady-state thermal resistance. It shows that, the thermal resistance of power devices is not a constant, it will vary with both power dissipation and air environment as a result of the current crowding phenomenon and the change of thermal conductivity of materials. The study deepens the understanding of the theory of thermal resistance and provided a reliable basis for the evaluation of thermal characteristics of power VDMOS devices.