.600-v High-voltage Vdmos Device Conduction Resistance Simulation And Optimization,

VDMOS (Vertical conduction Double-diffused Metal Oxide Semiconductor) is a widely used Power semiconductor device in automotive electronics,mobile communication, radar, motor control,switched-model Power converters,lamps ballasts and so forth, because it offers better performance in input impedance, switching speed,safety operating area and thermal stability than bipolar power transistor.This thesis designs a package of process for middle voltage, high current and power applications, which integrate 600V power VDMOS device with less on-resistance. This thesis mainly focuses on the on-resistance and current capacity design and optimizing. The main work of this thesis is as follows.1. By studying the operating theory and physical theory of VDMOS, and researching the composition of its on-resistor and the correlation between the on-resistor and the parameters of the device, according the computer simulation, in high voltage VDMOS (>500V), the on-resistor is mainly decided by the resistor of high-resistivity epitaxial layer, and based on this, the analytically physical model of on-resistor is built and the device's structure parameters are optimized.2. According to the application of VDMOS, we confirmed the electrical parameters of the power VDMOS device. First of all, on the basis of the device's threshold voltage and other parameters, we can predesign structure parameters of the power VDMOS cellular. And on the basis of device on-resistance study, we optimized the main factors of power VDMOS cellular on-resistance, such as poly width and the impurity concentration of epitaxial layer. Then by the device simulation and process device co-simulation, we fixed the conclusion of theoretical analysis, and get the finalization of the process steps of the VDMOS and process recipe of each step.3. According to the above, we run the first experimental lots, and tested the first lots samples. Through the analysis of the test results, further improvement were adopt to fix power VDMOS device on-resistance model, and further optimized the double-epilayers structure of device in order decrease the on-resistance and increase the current capacity.