Semiconductor device

摘要

A semiconductor device including a gate structure, a source region, a drain region, a first conductive type epitaxial layer, a high voltage second conductive type well, a linear graded high voltage first conductive type well and a first conductive type buried layer is provided. The first conductive type buried layer is located within the first conductive type epitaxial layer and below the high voltage second conductive type well, and a length of the first conductive type buried layer is smaller than a length of the high voltage second conductive type well.

主权项

1. A semiconductor device, comprising:
a first conductive type epitaxial layer, disposed on a second conductive type substrate; a high voltage second conductive type well, disposed within the first conductive type epitaxial layer; a first conductive type buried layer, disposed within the first conductive type epitaxial layer and below the high voltage second conductive type well; a source region, disposed within the high voltage second conductive type well; a linear graded high voltage first conductive type well, disposed within the first conductive type epitaxial layer, wherein the linear graded high voltage first conductive type well is a doped region having a lateral linear doping profile that has a doping concentration gradually increases from a location nearest the first conductive type buried layer to a location farther from the first conductive type buried layer, and a length of the first conductive type buried layer is smaller than a length of the high voltage second conductive type well, wherein one side of the first conductive type buried layer is pulled back with a pull-back length, such that the first conductive type buried layer is spaced away from the linear graded high voltage first conductive type well for the pull-back length; a drain region, disposed within the linear graded high voltage first conductive type well; and a gate structure, disposed above the first conductive type epitaxial layer and disposed between the source region and the drain region.