METHOD FOR MANUFACTURING FIELD STOP IGBT DEVICE

摘要

Provided is a method for manufacturing a field stop IGBT device. The method comprises the following steps: selecting an N-type doped FZ monocrystalline silicon wafer (01), wherein a thickness thereof is determined according to a voltage level; injecting phosphorus impurities with ions from a back surface of the silicon wafer (01) and annealing at a high temperature, so as to form an N-type doped buffer layer (02) with a thickness of 15-70μm and a doping concentration of 2×10¹³-2×10¹⁵/cm³; etching away a protective layer (01a) of the back surface, and roughening the back surface through a corrosion or abrasive blasting method to form a gettering source; removing the protective layer (01a, 01b) from a front surface, and manufacturing an IGBT cellular region (21) on the front surface of the silicon wafer; grinding a silicon substrate with a thickness of 5-30μm from the back surface of the silicon wafer, and then etching for a thickness of 2μm to leave the Ν-type buffer layer with a thickness of 10-65μm as a field stop region; and accomplishing the manufacturing of a collector region (22) of the back surface. The method does not need an expensive high-energy ion injection device or an epitaxial device and is applicable to the manufacturing of a 1700-6500V field stop IGBT device.