Silicon carbide semiconductor device and preparation method therefor

Abstract

The invention provides a silicon carbide semiconductor device which can be applied to a high-voltage field. The silicon carbide semiconductor device is formed by a plurality of cells in a parallel-connection manner; the structure of each cell comprises a p<+> substrate, an epitaxial layer, two ion injection n barrier regions, two ion injection p<+> shielding regions, two p<+> base regions, two n<+> source regions, a collector layer, two emitters, a gate oxide layer and a gate electrode, wherein the epitaxial layer is positioned on the substrate; the two ion injection n barrier regions are arranged on the two sides of the epitaxial layer respectively in an overlaying manner; the two ion injection p<+> shielding regions are arranged on the respective n barrier regions respectively in an overlaying manner; the two p<+> base regions are adjacent to the respective p<+> shielding regions respectively; the two n<+> source regions are arranged on the respective p<+> base regions in an overlaying manner respectively, and are adjacent to the p<+> base regions; the collector layer is positioned below the substrate; the two emitters are positioned on the respective p<+> base regions and the n<+> source regions respectively; the gate oxide layer is positioned on the two n<+> source regions; and the gate electrode is positioned on the gate oxide layer. In addition, the invention also provides a preparation method for the silicon carbide semiconductor device. Through ion injection, hole barrier is formed in the device, so that injection ratio of the emitters is improved and the conduction performance of the device is greatly improved.

Description

technical field [0001] The invention belongs to the field of silicon carbide semiconductor devices, and in particular relates to a silicon carbide semiconductor device and a preparation method thereof. Background technique [0002] Silicon carbide (SiC), as an emerging third-generation semiconductor material, has excellent physical and electrical properties. It has broad application prospects in fields such as electric vehicles, rail transit, smart grids, and green energy. [0003] SiC IGBT (Insulated Gate Bipolar Transistor) devices have the characteristics of fast switching speed of MOSFET (Metal Oxide Semiconductor Field Effect Transistor) devices and small on-resistance of BJT (Bipolar Transistor) devices, and have a wide range of applications in the field of power electronics prospect. By utilizing the conductivity modulation effect of the drift region, the resistance of the drift region of the IGBT is greatly reduced compared with that of the MOSFET. As a power devi...

AI Technical Summary

Problems solved by technology

As a power device, IGBT requires a thicker, lower-doped epitaxial drift region to support higher voltage, so the drift region voltage drop of SiC IGBT devices is still high, which limits the application of SiC IGBT devices

Images