碰撞电离雪崩渡越时间（IMPATT）二极管在毫米波频段能产生最高连续功率的输出，具有良好的输出特性，是目前最强大的一种微波频率固态源。而与此同时，第三代半导体材料的发展使得像SiC这样禁带宽度大、击穿场强高、热导率大、电子饱和漂移速度高、抗辐照能力强、稳定性良好的化合物半导体可以成功用于高频大功率器件的制造，在航空航天、核工业、军用电子等恶劣环境中均有着广袤的应用前景以及迫切的应用需求。在此背景下，本文以碳化硅（SiC）作为基底材料，利用Silvaco-ATLAS器件仿真平台对IMPATT二极管进行了深入性的研究。主要的研究成果如下： 1、对IMPATT二极管的基本工作机理进行了详细的研究，主要论述了其注入相位延迟和渡越时间效应，理论性分析了IMPATT器件的静态特性、动态特性及功率和频率等相关内容。 2、系统地研究了热学限制、寄生串联电阻限制和噪声限制等这几种影响实际SiC基IMPATT二极管输出性能的因素。 3、通过Sivalco TCAD软件中的ATLAS器件仿真平台，对SiC基IMPATT二极管进行了几种组成结构的建模及仿真，并获取了器件的直流I-V特性及反向击穿电压。从所得到的曲线图中，我们可以观察到IMPATT器件具有明显的负阻特性，并进一步推出：双漂移型碰撞电离雪崩渡越时间二极管比单漂移型碰撞电离雪崩渡越时间二极管具有更显著的输出性能。这种IMPATT器件的大功率和高频特性在微波、毫米波器件中有很好的应用前景。 4、在ATLAS-MixedMode二维器件电路仿真平台下，我们对双漂移区SiC基IMPATT二极管搭建其电压源偏置电路，从而进行了其交流特性的模拟及分析。当外加直流电压为135V时，室温下双漂移区SiC基IMPATT器件的振荡频率是325GHz，其最大射频功率为3.69×1011W/m2，直流到射频的最大转换效率为14%，显示出非常良好的输出性能。 综上，本文对SiC基IMPATT器件进行了仿真角度的详细研究。通过理论分析及模拟结果，我们得到SiC基IMPATT二极管可以作为高工作频率，耐高温的大功率半导体THz固态器件，其在IT产业和太赫兹应用中具有相当大的优势和潜力。

The impact ionization avalanche transit time (IMPATT) diode can produce the maximum continuous output power in the millimeter wave band, which has the excellent output characteristics and is a solid state source of the most powerful microwave frequencies. At the same time, the development of the third generation semiconductor materials makes SiC such a large band gap, high breakdown field strength, high thermal conductivity, high saturated electron drift velocity, strong ability of anti-radiation and good stability compound semiconductor can be successfully used in the manufacture of the high frequency and high power devices. The material of SiC has a vast application prospects as well as urgent needs in the harsh environment of the aerospace, the nuclear industry and the military electronics. In this context, we conduct an in-depth research on the IMPATT diodes with silicon carbide (SiC) as the base material by using the Silvaco-ATLAS device simulation platform. The main results are as follows: 1、We study the basic mechanism of the IMPATT diode in detail, mainly discuss its injection phase delay and the transit time effect, theoretically analyze the static characteristics, the dynamic characteristics, the power and frequency of the IMPATT device as well. 2、We conduct a systematic research on the factors that affect the actual output performance of the SiC based IMPATT diodes, which are the thermal limits, the parasitic series resistance limits and the noise restrictions. 3、By the use of the ATLAS device simulation platform in the Sivalco TCAD software, we establish the modeling and simulate on the SiC based IMPATT diodes of several structures. Meanwhile, we have access to the DC I-V characteristics and the reverse breakdown voltages of the devices. From the graph, we can observe that the IMPATT devices have the obvious negative resistance characteristics, and further derivate that the double drift type impact ionization avalanche transit time diodes have a much more significant output performance than the single drift type impact ionization avalanche transit time diodes. The high power and high frequency characteristics of this type of the IMPATT devices have good application prospects in the microwave and millimeter wave devices. 4、We build a bias circuit of the voltage source of the double drift region SiC based IMPATT diode by using the ATLAS-MixedMode 2D device circuit simulation platform, and perform the AC characteristics’ simulation and analysis of the device. When the applied DC voltage is 135V, the oscillation frequency of the double drift region SiC based IMPATT device is 325GHz at room temperature, the maximum RF power is 3.69×1011W/m2 and the biggest DC to RF conversion efficiency is 14%, showing a very good output performance. In summary, we study the SiC based IMPATT devices on the simulation angle in detail in this paper. Through theoretical analyses and simulation results, we conclude that the SiC based IMPATT diode can be used as a high operating frequency, high temperature and high power semiconductor THz solid state device. Besides, the SiC based IMPATT diode has considerable advantages and potential in the IT industry and terahertz applications.