Research Andsimulation Of HEMT Devices

In the modern science and technology, the development level of integrated circuit(IC) industry reflects the developed degree of a country’s science and technology, and it is an important reflection of a country’s competitive power of science and technology. Semiconductor devices are the basis of integrated circuit. As an important and efficient means to develop semiconductor device, semiconductor device simulation technology of the computer’s position is particularly important. In addition, new semiconductor devices which based on the third generation wide bandgap materials are a hotspot. Especially the HEMT device, as its high electron mobility, received extensive attention and application.In this context, this thesis firstly introduces the basic theory of the semiconductor device simulationand researches the working principle of HEMT device,then studies the physical model of the third generation semiconductor materials,finally build a typical HEMT device model structure, and its characteristics are simulated.The summary of the work up are as follows:1. This paper briefly introduces the development of semiconductor materialsand HEMT device, the related concept of computer simulation technology, development and research status of domestic and foreign TCAD software.2. A detailed introduction of the semiconductor device simulation, the theory of Poisson equation of carrier transport equation and the current continuity equation and its physical meaning. At the same time, complete the derivation of the classical drift diffusion model(DDM) through the basic equation.3. Introduced GaN/AlGaN heterostructure, the spontaneous polarization and Piezoelectric polarization of the heterogeneous structure, given the concept of 2D electron gas and the formation mechanism, described the working principle of typical HEMT device.4. Access to relevant literature and technical information, confirmed the energy band model, mobility model, composite rate model of GaN and AlGaN materials, and these models are summarized. Then the physical model is realized by C++ language code,and add it into the Genius source code.5. Homogeneous PN junction and heterogeneity PN junction were simulated by TheGENIUS software, get the built-in potential of PN junction, IV curve. Verify material model is accurate or not. Introduced the two-dimensional electron gas in the simulation, and simulated the HEMT device structure, obtained the characteristics of the device interface charge and output curve, which been made a comprehensive comparison with the results of SILVACO.