Lateral insulated gate bipolar device with double trench high voltage shielding and its preparation method

Abstract

A double-trench high-voltage shielded lateral insulated-gate bipolar device and a preparation method thereof are provided. The bipolar device comprises a P-type substrate, a buried oxide layer, and an N-type epitaxial layer. A P-type body region and an N-type buffer layer are disposed in the N-type epitaxial layer. A P-type emitter and an N-type emitter are disposed in the P-type body region. A polysilicon gate is arranged over the N-type emitter and is provided with metal which connect the polysilicon gate to a structure peripheral input / output. A P-type collector is disposed in the N-type buffer layer. A polysilicon field plate is disposed over the N-type buffer layer and is connected with gate metal. Three sides of the P-type body region are surrounded by the N-type buffer layer but the other side of the P-type body region is not. The P-type collector is a collector metallic connection line. A trench is arranged under the collector metallic connection line and close to a structure edge and is doped with a dielectric. The entire structure is surrounded by the trench doped with the dielectric. The bottom of the trench of the high-voltage interconnection line shielding structure is not in contact with the buried oxide layer and a gap is provided.

Description

technical field [0001] The invention mainly relates to the technical field of power integrated circuits, specifically, it is especially suitable for many power control and processing fields such as switching power supplies, motor control, automotive electronic systems, and household appliances. Background technique [0002] High-voltage power integration technology is the product of the combination of VLSI and power devices. The high-voltage integrated circuit integrating low-voltage control circuit and high-voltage power element on the same chip greatly reduces the number of electronic components required by the electronic system, thereby reducing system cost, reducing equipment size, and improving system reliability. [0003] High-voltage integrated circuits have been widely used in a wide range of fields including electronic lighting, motor drive, power management, industrial control, and display drive. The development and application of high-voltage integrated circuits ...

AI Technical Summary

Problems solved by technology

Aiming at the problem of reduced withstand voltage caused by high-voltage interconnection lines, the present invention proposes a new type of shielding structure for high-voltage interconnection lines, which greatly improves the withstand voltage under the high-voltage interconnection lines and improves the reliability of the entire high-voltage integrated circuit

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