Power semiconductor device with L shaped source

Abstract

This invention relates to L type source region power semiconductor device. It includes one substrate, one trap area formed in the substrate, one body area formed on trap area, one groove grid formed at both sides of the trap area, one grid oxide layer is formed on the lateral wall and bottom surface of the groove grid, one L type source region, and one flat roof area and one straight lateral area are formed on roof and sides of the body, one dielectric insulating layer formed on the groove grid area and part of the L type area, and one contact window is defined, one metal layer formed on the insulating layer, the body and the L type area, and it is connected to the L type area through the contact window to form the power semiconductor device with L type area flush type groove grid.

Description

technical field [0001] The present invention relates to a power semiconductor device structure, in particular to a power semiconductor device structure with an L-shaped source region. Background technique [0002] In recent years, power semiconductor devices, such as metal oxide semiconductor field effect transistor (MOSFET), insulated gate bipolar transistor (IGBT), junction field effect transistor (Junction FieldEffect Transistor, JFET) or rectifier diodes (Rectifier), etc., have made extremely good progress in their operational performance and manufacturing process. However, in order to further improve the characteristics of the device and reduce the manufacturing cost, one of the main trends is to use the so-called trench-gated technology. However, when using this trench gate technology, the cell pitch of the device is reduced, and the device channel density of the device is significantly increased. Such a low on-state power loss can be achieved by forming low on-resis...

AI Technical Summary

Problems solved by technology

First, since the P+ type body region 13 is deeper than the N+ type source region 16, the channel region is exposed to the P+ type body region 13, and the dopant in the P+ region will easily enter the channel, resulting in a high and uncontrollable channel region. The threshold voltage (threshold voltage)

On the other hand, the deeply implanted P+ type body region 13 will limit the depletion region distribution in the P+ region

Therefore, when the depth of the P+ type body region 13 increases, the breakdown voltage (breakdown voltage) of the device will be limited or even reduced.

[0006] In view of known power semiconductor devices, the breakdown voltage (breakdown voltage) will be limited or even reduced due to the depth of the body region, and the threshold voltage (threshold voltage) will also be affected by the dopant in the P+ type region structure. Channel, As a result, the electrical properties of the overall device are affected

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