Power device with multiple floating field plates and collector PMOS structure

Abstract

The invention belongs to the technical field of power semiconductors, and particularly relates to a power device with multiple floating fields and a collector PMOS structure. Compared with a traditional structure, a self-adaptive PMOS structure is introduced to a collector end, and a discontinuous floating field plate is adopted on the surface of a drift region. During forward conduction, the PMOS channel at the collector end is closed, the electron extraction path at the collector end is blocked to eliminate the voltage turn-back effect, the carrier concentration of the drift region is improved due to the existence of the blocking trench gate, and the new device can obtain low forward conduction voltage drop. In the turn-off process, the collector PMOS channel is adaptively opened along with the rise of the collector voltage to form an electron extraction path, and the accelerator is turned off to reduce the turn-off loss. Meanwhile, due to the existence of the floating field plate group, the surface electric field of the device is optimized in a blocking state, so that the length of a drift region of a new device can be shortened under the condition that the withstand voltage level is kept unchanged, and the conduction voltage drop and the turn-off loss of the device are further reduced.

Description

technical field [0001] The invention belongs to the technical field of power semiconductors, and relates to a SOI LIGBT (Lateral Insulated Gate Bipolar Transistor, lateral insulated gate bipolar transistor) with multiple floating field plates and a collector PMOS structure. Background technique [0002] The insulated gate bipolar transistor is a gate-controlled bipolar conduction device. Its gate-control characteristics make it have the advantages of high input impedance and easy driving, and its bipolar conduction method is easy to achieve low conduction voltage drop and Large current density, so it is widely used in high-voltage and high-power power electronics fields such as smart grids, rail transit, and industrial control. Semiconductor devices based on SOI technology can achieve full dielectric isolation, with lower leakage current and smaller parasitic effects. [0003] During forward conduction, the conductance modulation effect will occur in the drift region of LIG...

AI Technical Summary

Problems solved by technology

Shortening the length of the drift region can not only reduce the turn-on voltage drop of the device, but also reduce the number of excess carriers stored in the drift region, thereby reducing the tail current during the turn-off process and reducing the turn-off loss, but obviously the length of the drift region shortening will result in lower device withstand voltage

Images