Device with schottky diode integrated in power metal oxide semiconductor (MOS) transistor and manufacturing method thereof

Abstract

The invention discloses a device with a schottky diode integrated in a power metal oxide semiconductor (MOS) transistor. Schottky grooves are formed between the regular grid grooves, and the schottky diodes are formed between the schottky grooves. Moreover, the invention also discloses a method for manufacturing the device, which comprises the following steps of: (1) etching grid grooves and schottky grooves on a silicon substrate, wherein the schottky grooves are between the formed grid grooves; (2) performing body injection and active injection into the schottky channel region with a photoresist barrier; (3) depositing an interlayer dielectric medium, exposing and etching a contact hole, and performing contact hole injection to form ohm contact; (4) exposing and etching schottky contact groove; (5) depositing metal, performing contact at the bottom of the schottky contact groove, metal and an epitaxial layer to form a schottky diode; and (6) performing subsequent processes including regular metal exposure, etching and alloying. The device improves the alternative frequency characteristics of apparatus on the premise of not increasing the chip area.

Description

technical field [0001] The invention relates to a semiconductor integrated circuit manufacturing technology, in particular to a device integrating a Schottky diode in a power MOS transistor, and also relates to a manufacturing process method of the device. Background technique [0002] In semiconductor integrated circuits, the existing typical power MOS (metal oxide semiconductor) transistor structure is as follows figure 1 shown. It controls the opening of the vertical channel through the channel gate to realize the switching function of the MOS tube. [0003] In order to improve the cross-frequency characteristics of the device, the current common method is to integrate a Schottky diode on the power MOS transistor chip, mostly a separate device, that is, a Schottky diode chip is connected in parallel next to the original power MOS transistor chip. Although this method It can improve the cross-frequency characteristics of the device, but there are disadvantages such as in...

AI Technical Summary

Problems solved by technology

[0003] In order to improve the cross-frequency characteristics of the device, the current common method is to integrate a Schottky diode on the power MOS transistor chip, mostly a separate device, that is, a Schottky diode chip is connected in parallel next to the original power MOS transistor chip. Although this method It can improve the cross-frequency characteristics of the device, but there are disadvantages such as insufficient optimization of the process flow, increased chip area, and high unit chip cost.

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