Isolation structure of high-voltage driving circuit

Abstract

The invention discloses an isolation structure of a high-voltage driving circuit, and the isolation structure comprises a P-type substrate on which a P-type epitaxial layer is arranged, wherein a high-voltage region, a low-voltage region, a high-low-voltage junction terminal region, a first P-type junction isolation region and a half-ring P-type junction isolation region are arranged on the P-type epitaxial layer, and both ends of the half-ring P-type junction isolation region are connected with the first P-type junction isolation region. The isolation structure provided by the invention is characterized in that the half-ring P-type junction isolation region is composed of a half-ring P-type buried layer and a half-ring P-type well region, the half-ring P-type well region is positioned above the half-ring P-type buried layer; a first slot and a second slot are respectively arranged between two ends of the half-ring P-type buried layer and the first P-type junction isolation region, and the P-type substrate and the P-type epitaxial extend towards and fill the first slot and the second slot. The problem of localized breakdown in the high-low-voltage junction terminal region caused by the P-type buried layer is solved by using the isolation structure; therefore, an LDMOS (laterally-diffused metal oxide semiconductor) is effectively isolated from peripheral parts.

Description

technical field [0001] The invention relates to a high-voltage half-bridge gate drive circuit in a high-voltage power integrated circuit, and relates to an isolation structure in an integrated high-voltage drive circuit. Background technique [0002] High-voltage half-bridge drive circuits are used in various fields such as motor drives, electronic ballasts in fluorescent lamps, and power management. In the half-bridge drive circuit, the level shift circuit is the key part of the whole circuit. The electrical performance of the high-voltage LDMOS constituting the level shift circuit and the electrical coupling between the high-voltage LDMOS will affect the performance of the shift circuit. The source and drain of the high-voltage LDMOS Large current and high voltage will also cause parasitic effects in other areas of the entire integrated circuit and thus affect the electrical performance of the entire integrated circuit. Therefore, the electrical performance of the high-vol...

AI Technical Summary

Problems solved by technology

[0004] The invention provides an isolation structure used in a high-voltage drive circuit. This patent solves the partial breakdown caused by the incomplete depletion of the P-type isolation structure far away from the drain end, and improves the withstand voltage of the isolation structure.

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