Method for manufacturing SOI (silicon on insulator) LIGBT (lateral insulated gate bipolar transistor) device unit with p buried layer and longitudinal channel

Abstract

The invention relates to a method for manufacturing an SOI (silicon on insulator) LIGBT (lateral insulated gate bipolar transistor) device unit with a p buried layer and a longitudinal channel. The SOI LIGBT device manufactured by the existing method abruptly degrades and even becomes invalid under a high temperature and large current. In the method, SOI materials with p-type buried layers are adopted to manufacture the SOI LIGBT device with the longitudinal channel; the longitudinal withstand voltage is mainly borne by a reversely biased pn junction depletion layer formed by a p-type buried layer with backward impurity concentration distribution and an n-type top layer semiconductor with forward impurity concentration distribution; and the SOI LIGBT device unit is manufactured through ten-time etching and seven-time oxidizing. The method has the beneficial effects of effectively reducing the on-state resistance, on-state voltage drop and on-state power consumption of the device, improving the on-state current and working efficiency of the device, obviously improving the performance of the SOI LIGBT device and improving the reliability of the device.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and relates to a SOI CMOS VLSI process realization method of a vertical channel SOI (silicon on insulating layer) LIGBT (lateral insulated gate bipolar transistor) device structure of a p-buried layer. Background technique [0002] Due to its small size, weight, high operating temperature and strong radiation resistance, low cost and high reliability, SOI LIGBT devices are used as non-contact power electronic switches or power drivers in smart power It is widely used in electronics, high temperature environment power electronics, space power electronics and vehicle power electronics. SOI CMOS VLSI process technology has advantages such as high process maturity, good dielectric isolation performance, simple isolation process, easy three-dimensional integration, easy integration of micro-optical electromechanical and power and radio frequency monolithic systems, and easy improvement of integ...

AI Technical Summary

Problems solved by technology

Because the thermal conductivity of the oxide layer is very low and the thickness is very large, it brings serious self-heating problems and strict heat dissipation requirements to such high-voltage, high-current, and high-power devices. The device must be installed in the process of use. The heat sink is not conducive to energy saving and environmental protection; and when this type of device is turned on, the conductive channel is located on the front surface of the top layer, and the gate field plate is covered on the thicker field oxide layer, resulting in the on-state current flowing to the drift region. The surface is concentrated, the expansion resistance is large, the conductance modulation effect in the drift region is uneven, the on-state resistance is large, the on-state voltage drop is high, the on-state current is small, and the on-state power consumption is high, the device's working efficiency is low, and the temperature rises quickly, which is not conducive to improving Device and System Reliability