A Diffusion Method of Buffer Layer

Abstract

The invention provides a buffer layer diffusion method, belongs to the technical field of semiconductor manufacture, and is mainly to solve the problems of high cost, low efficiency, very large influence on other parameters and difficult control in the preparation of a buffer layer through ion implantation and high-temperature propulsion mode at present. The buffer layer diffusion method is mainly characterized in that the method comprises the following steps: cleansing and drying a bucket boat, an arc boat, test wafers and silicon wafers; putting the bucket boat, the arc boat, and the test wafers into a diffusion tube for carrying out source-pass doped diffusion to enable the surfaces thereof to be respectively accumulated with a layer of uniform impurity atoms; cleansing and drying the bucket boat, the arc boat, and the test wafers above, and arranging the test wafers and the silicon wafers in a manner that one test wafer and two silicon wafers are in lamination arrangement; putting the bucket boat, the arc boat, the test wafers and the silicon wafers into a diffusion furnace tube for high-temperature pre-diffusion; and taking out the silicon wafers and putting the silicon wafers on the arc boat, and then putting the arc boat into a high-temperature diffusion furnace for carrying out buffer layer propulsion diffusion. The buffer layer diffusion method has the advantages that an existing common processing line can realize buffer layer diffusion, low cost, short propulsion diffusion time, and the effect of not being influenced by types of impurities, and the method is mainly used for buffer layer diffusion of a power semiconductor device chip.

Description

technical field [0001] The invention belongs to the technical field of semiconductor manufacturing. The invention relates to a buffer layer diffusion method of a power semiconductor device chip. Specifically, it is a buffer layer phosphorus or aluminum atom transfer diffusion method. Background technique [0002] With the development of semiconductor device manufacturing technology, the requirements for devices such as high voltage, high current, and low voltage drop are also getting higher and higher. To meet the demand, buffer layer technology is introduced in semiconductor manufacturing technology. [0003] Since the buffer layer requires a relatively shallow concentration and a certain junction depth, the gas-carrying source diffusion method of the existing common process has a high concentration, so it is difficult for the gas-carrying source diffusion method to reach the shallow concentration required by the buffer layer. For this reason, the current buffer layer di...

AI Technical Summary

Problems solved by technology

Due to the special equipment required for ion implantation and the long time of propulsion and diffusion, the cost of ion implantation is high and the efficiency is low, and the long-term high-temperature propulsion has a great impact on other parameters and is difficult to control

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