High-voltage semiconductor device and manufacturing method thereof

Abstract

The invention provides a high-voltage semiconductor device and a manufacturing method thereof. The high-voltage semiconductor device comprises a semiconductor substrate, a first grid gate structure, a second gate structure, a first injection region, a second injection region and a back-injection region, and is characterized in that the semiconductor substrate is provided with a well region with a first conduction type and an isolation structure located in the well region, and a first region and a second region are respectively defined at two sides of the isolation structure; the first gate structure and the second gate structure are respectively arranged in the first region and the second region; the first injection region and the second injection region with a second conduction type, which is different from the first conduction type, are respectively located in the first region and the second region and are adjacent to the isolation structure; the back-injection region is located in the well region below the isolation structure and transversely extends below the first injection region and the second injection region; and the back-injection region has a first conduction type, and the doping concentration of the back-injection region is greater than the doping concentration of the well region. The capacity of isolation between adjacent high-voltage semiconductor devices is improved by using the back-injection region, and thus the device size or the chip area is reduced by shortening the distance between the high-voltage semiconductor devices.

Description

technical field [0001] The present application relates to a semiconductor technology, and in particular to a high-voltage semiconductor device with good isolation capability. Background technique [0002] High-voltage semiconductor device technology is suitable for high-voltage and high-power integrated circuits. Traditional high-voltage semiconductor devices, such as double diffused drain metal oxide half field effect transistor (Double Diffused Drain MOSFET, DDDMOS) and lateral diffused metal oxide half field effect transistor (Lateral diffused MOSFET, LDMOS), are mainly used for For 18V component applications. The advantage of high-voltage semiconductor device technology is that it is cost-effective and easily compatible with other processes. It has been widely used in the fields of display driver IC components, power supplies, power management, communications, automotive electronics, or industrial control. [0003] Double diffused drain metal oxide half field effect tr...

AI Technical Summary

Problems solved by technology

[0005] However, increasing the width of the trench isolation structure increases the size of the device resulting in an increase in wafer area

In addition, increasing the depth of the trench isolation structure will increase the difficulty of the process and the manufacturing cost

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