Patent ID: 7301201
Filing Date: 2007-11-27
Classification: H01L

Abstract:
1. A high voltage device, comprising: an N-type drift region and a P-type drift region formed on a substrate; a gate region defined at an intersection between the N and P-type drift region, the gate region having an oxide film deposited on an upper portion of the gate region and a gate electrode formed on the oxide film; a source region being defined in one of the N and P-type drift regions, the source region having a first trench filled with a first polysilicon layer, a first high density diffusion layer formed on an upper portion of the first polysilicon layer and a source electrode formed on the high density diffusion layer; a drain region being defined in the other of the N and P-type drift regions, the drain region having a second high density diffusion layer formed on an upper portion of the drain region and a drain electrode formed on the second high density diffusion layer; and a second polysilicon layer filling a second trench formed between the N and P-type drift regions of the gate region such that the oxide film is deposited in the second trench as well as the upper portion of the drift region corresponding to the drain region.