IGBT device manufacturing method and device

Abstract

The invention relates to the technical field of a semiconductor device, and especially relates to an IGBT device manufacturing method and device. The method comprises the following steps: carrying out epitaxy on a P+ substrate through epitaxy technology to obtain a voltage withstand drift region, a P-type body area epitaxial layer and an N+ source region epitaxial layer in sequence, which form a base body; through photoetching and etching technique, providing a gate trench and a Schottky groove in the base body; carrying out thermal oxidation on the inner wall of the gate trench to form a gate oxide layer; forming a gate electrode on the inner wall of the gate oxide layer through deposition, photoetching and etching; carrying out passivation layer deposition on the outer surface of the gate electrode, and forming a gate electrode insulation protection layer through photoetching and etching; lastly, carrying out Schottky barrier metal deposition and annealing on the surface of the Schottky groove to form a Schottky diode; and finally, obtaining an IGBT device. According to the IGBT device manufacturing method and device, impurity doping and diffusion processes are saved, and reliability of the gate oxide layer is enhanced.

Description

technical field [0001] The invention relates to the technical field of semiconductor devices, in particular to a method for manufacturing an IGBT device and the device. Background technique [0002] Wide bandgap semiconductor IGBT devices, especially silicon carbide IGBT devices and gallium nitride IGBT devices, are power switching devices that have attracted much attention at present. Its driving circuit is very simple and has good compatibility with existing power device driving circuits. . [0003] IGBT (Insulated Gate Bipolar Transistor) is a composite fully-controlled voltage-driven power semiconductor device composed of BJT (Bipolar Transistor) and MOSFET (Metal Oxide Semiconductor Transistor), which combines the high input impedance of MOSFET and BJT (also known as GTR) has the advantages of low conduction voltage drop. Among them, the vertical IGBT device and the P-type emission area on the back of the chip are mainly realized by ion implantation technology and epi...

AI Technical Summary

Problems solved by technology

[0004] There are two main technical problems in the design of wide bandgap semiconductor IGBT devices: one is the low channel electron mobility, which leads to the problem of large channel resistance of MOSFET; the other is the insufficient reliability of gate oxide under high temperature and high electric field. Therefore, the main technical problem in the design of wide bandgap semiconductor IGBT devices lies in the above-mentioned technical problems faced by wide bandgap semiconductor MOSFET devices

[0006] One is to choose a suitable crystal orientation, because the electron mobility of different crystal orientations is different, and the mobility can differ by up to 5 times, so the crystal surface with high electron mobility is selected to form a channel; because the crystal orientation of silicon carbide is chaotic, so Crystal faces with high electron mobility are not easy to choose

[0007] The second is to improve the state of the channel interface and increase the electron mobility of the channel through a special annealing process; this special annealing process is inconvenient to operate

[0008] For the reliability of the trench gate oxide, the solution is mainly to use special gate oxide materials, such as AlN, AlON and other materials; but only relying on special gate oxide materials cannot well solve the problem of trench gate oxide reliability

[0009] In addition, there are still difficulties in the process of wide bandgap semiconductor IGBT devices. This difficulty mainly lies in the form of the PN junction. The PN junction needs a suitable impurity concentration and distribution. Perform high-temperature annealing; multiple injections of high-temperature and high-energy ions will damage the crystal lattice of wide-bandgap semiconductor materials, and require the manufacturer to purchase new equipment or new materials, which will result in a large investment of fixed funds and increase costs

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