Patent ID: 9484437
Filing Date: 2016-11-01
CPC Classification: H01L

Claim Text:
1. A manufacturing method of a lateral double diffused metal oxide semiconductor (LDMOS) device, comprising: providing a substrate with a first conductive type; forming with a second conductive type a drift region on the substrate, wherein the second conductive type is opposite to the first conductive type; forming an isolation oxide region on the drift region to define an operation region, wherein the operation region is located in the drift region; forming a first oxide region on the drift region in the operation region having a first thickness; forming a second oxide region on the drift region in the operation region having a second thickness without affecting the first thickness of the first oxide region, wherein the second oxide region is directly connected to the first oxide region in a lateral direction, wherein the second thickness is less than the first thickness; forming a gate on the drift region in the operation region, which overlays at least part of the second oxide region and part of the first oxide region, including: forming a body region with a first conductive type in the drift region, and part of the body region is beneath the gate; forming a source with the second conductive type in the body region, wherein the spacer layer is located between the source and the stack layer from a top view; and forming a drain with the second conductive type in the drift region, which is located between the first oxide region and the isolation oxide region; wherein the first oxide region and the second oxide region are first and second local oxidation of silicon (LOCOS) structures respectively, and the isolation oxide region is a shallow trench isolation (STI) structure or a third local oxidation of silicon (LOCOS) structure; and wherein the isolation oxide region, the drain, the first oxide region, the second oxide region, and the dielectric layer are sequentially connected in the lateral direction.