Research And Simulation Of Static Induction Transistor

With the development of high technology and people’s pursuit for high-quality living conditions, the power semiconductor devices replacement cycle is becoming faster. Usually the product development cycle includes the theoretical study, product tests and mass production, therefore, mature theory and the computer-aided design based on software are crucial to improve the test success rate and a shorter product time-to-market.At present, static induction transistor as a new type of semiconductor device, the process of practice stays ahead of theoretical research and also the computer aided design does not see more. Therefore, in this thesis, the static induction transistor was simulated for explaining the physical mechanism of the device operation and the key parameters of the device structure were optimized by using the semiconductor simulation software Silvaco Tcad. This thesis mainly includes the following four aspects.The first thing was that the structure type and the working mechanism of static induction transistor were introduced briefly. On the basis of the introduction of several common types of static induction device, it was determined that the device structure of this thesis was the surface gate static induction transistor based on silicon from two aspects of the similar in performance and the principle of representative.The second thing was to start from the simulation software Silvaco Tcad to build a device simulation model. Firstly, semiconductor simulation software Silvaco Tcad was simply presented; Secondly, regarding the surface gate static induction transistor device based on Si substrate,the research object was defined from the aspects of the basic equations, the material properties, the interface properties, the physical model, the ionization model and the boundary conditions, etc.The third thing was to start from the point of technology to simulate process of the static induction transistor. Regarding the Athene module of Silvaco Tcad software as technology simulation platform, the research object was simulated from the technology of oxidation, diffusion, ion implantation, photo etching and epitaxy, etc. The focus was through the contrast and analysis, the method of ion implantation was selected to form the gate region instead of the method of traditional diffusion, because its lateral diffusion is smaller and PN junction is more accurate, in addition, the source region adopted fast annealing to form secondary distribution of the impurities and eliminate the lattice damage.The last thing was to start from the point of device simulation to analyze the key structure parameters affecting the device electrical performance. This process was based on the device simulation module Atlas of Silvaco Tcad software. On the one hand, the classpentode saturated characteristic curve and the class triode unsaturated characteristic curve of device were simulated and analyzed, and the formation mechanism of channel barrier was analyzed by changing the reverse gate voltage and drain bias voltage; On the other hand, the key structure parameters affecting the device voltage-current characteristic curve were simulated and analyzed, the interdependent relationships were confirmed between the all electrical performance parameters and the channel parameters, the source region parameters, drift layer parameters. All of these are parts of work in order to get the optimal structural parameters of the device required the corresponding device performance and be the theoretical guidance for the practice of the device technology.