Abstract: This topic utilizes Nuwa TCAD software to simulate the electrical characteristics of Si MOSFET, SBD, PIN, IGBT, and MPS devices. It demonstrates the construction of device structures, physical model settings, and simulation results, aiming to help users fully understand Nuwa TCAD software and learn to use it for the simulation and design of Si power devices.
In the 1950s, bipolar silicon (Si) power devices successfully replaced vacuum tubes. Subsequently, Si bipolar transistors and thyristors developed rapidly. However, the bulky control and protection circuits for Si power devices led to high costs. With the emergence of metal-oxide semiconductor (MOS) technology for digital circuits, a new class of devices was developed for power switching applications in the 1970s. These silicon power metal-oxide semiconductor field-effect transistors (MOSFETs) were widely used in high-frequency applications with relatively low operating voltages (below 100V). In the 1980s, the combination of MOS and bipolar physics created another silicon device— the insulated gate bipolar transistor (IGBT). The high power density, simple interface, and robustness of IGBTs made them the preferred technology for all medium- to high-power applications. In the 1990s, researchers proposed the concept of two-dimensional charge coupling and introduced two fundamental methods to significantly reduce the on-state resistance of silicon power devices [1]. The first method used source connection electrodes embedded in deep vertical trenches, leading to a new generation of commercial silicon power devices with ratings between 30V and 200V. The second method used vertical pillars with alternating P-type and N-type silicon regions, and products utilizing this method, with blocking voltages around 600V, have been commercialized. Today, silicon (Si) semiconductor material remains the most widely applied material in the field of power electronics.
Si semiconductor power devices primarily include two categories: diode types, which mainly comprise Schottky diodes (SBD), junction barrier Schottky diodes (JBS), and PIN power diodes (PIN); and transistor types, which mainly comprise metal-oxide semiconductor field-effect transistors (MOSFETs), insulated gate bipolar transistors (IGBTs), junction field-effect transistors (JFETs), bipolar transistors (BJTs), and thyristors.
Currently, Si power devices still face numerous challenges, such as heat dissipation, reliability, and performance degradation, while also contending with competition from SiC- and GaN-based power devices. Therefore, Si power devices require continuous optimization of processes and structures, and theoretical research to enhance their electrical properties. Device simulation not only enables quick analysis of internal mechanisms, structural optimization, and performance validation of new devices, but also significantly improves product development efficiency and reduces costs, making it an essential tool for semiconductor device research and design.
This topic presents simulations of various Si power devices using semiconductor device simulation software, covering the construction of device structures, physical model parameter settings, calculations, simulations, and result analysis. The goal is to help software users quickly grasp the use of the software, understand the physics of various types of Si semiconductor devices through simulation, and identify structures and methods to improve the performance of Si power devices.
This topic uses the Nuwa TCAD to simulate Si power devices. Nuwa TCAD is a 2D & 3D domestic semiconductor process and device simulation software that includes self-consistent solutions for semiconductor drift-diffusion basic equations across multiple physical fields (optical, electrical, thermal, mechanical). It integrates various physical models such as defects, SRH recombination, Auger recombination, carrier tunneling, impact ionization, mobility, thermionic emission, and self-heating effects, enabling the simulation of the physical mechanisms and electrical characteristics of Si power devices. It outputs spatial distributions of various physical quantities, forward and reverse V characteristics of Si power devices, which can be used to analyze device internal mechanisms and optimize device structures.