Temperature Measurement and Numerical Simulation of Semiconductor Bridge in Constant Current

The temperature of electric initiating device under constant current has the vital significance to security and firing performance of electrical explosive initiator. Semiconductor bridge which is representative in electrical explosive devices has been widely used for excellent performances. In this study, the heavily doped polysilicon thin film was chosen as semiconductor bridge. Temperature changes of semiconductor bridge under different currents were measured using the infrared microscopic thermographer. The experimental results show that the maximum temperature of semiconductor bridge ascends while current rises from 0.70 A to 0.90 A. Based on the data analysis of infrared temperature measurement, steady-state mathematical model rho cdT/dt=IU - lambda(con)(T-T-0)-A epsilon sigma(T-4-T-0(4)) of semiconductor bridge was established. Through consumed time and temperature at thermodynamic equilibrium, the thermal conductivity and heat capacity of semiconductor bridge were determined and the simplified formula Tn=(IR)-R-2(T)Delta t+rho cT(n-1)+lambda T-tot(0)Delta t/rho c+lambda(tot)Delta t was obtained. Then the simulation curve of temperature changes at different current is generated by corresponding calculation procedure. The simulated curve is in good agreement with experimental results.