A trench gate power field effect transistor

Abstract

The invention discloses a trough-type gate power field effect transistor. The trough-type gate power field effect transistor comprises a substrate, an epitaxial layer, a gate structure, a first well region and a second well region, wherein the gate structure comprises a trough-type gate and a gate oxidation layer surrounding the trough-type gate, wherein the doping types of the substrate, the epitaxial layer and the second well region are first doping types respectively, and the doping type of the first well region is a second doping type; the second well region is conductively connected with a source electrode, and the substrate is conductively connected with a drain electrode, wherein the gate structure is filled between the second well region and the epitaxial layer along the direction vertical to the surface of the substrate so as to reduce parasitic resistance on the side, away from the surface of the epitaxial layer, of the second well region. The device provided by the invention is used for solving the technical problem that the device is low in avalanche reliability existing due to weak optimization effect for an optimization technology of avalanche tolerance capacity of the trough-type gate power field effect transistor in the prior art. The technical effect of greatly improving the avalanche tolerance reliability level of the device is realized.

Description

technical field

[0001] The invention relates to the field of semiconductors, in particular to a slot gate power field effect transistor. Background technique

[0002] Trench power MOSFET (trench power MOSFET) is widely used in the field of power control due to its low on-state voltage drop, high frequency working capability, simple drive control, high power density and easy parallel connection, and is currently the mainstream power MOSFET. One of the devices. Its most common application is as a power switch to control power conversion, usually to control and drive inductive loads. Therefore, the device will experience high-frequency switching action during the working process. When the device is in the off state, the energy stored in the unclamped load inductance driven by the device will be released to the device in an instant, causing an impact on the device. These released The energy of the device will cause an avalanche phenomenon inside the device, resulting in an ins...

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