Patent ID: 7808037
Filing Date: 2010-10-05
Classification: H01L

Abstract:
1. A high-voltage semiconductor device comprising: a silicon substrate having a main surface; a gate on the main surface of the silicon substrate; a source region in a portion of the silicon substrate proximate to the main surface; a drain region in a portion of the silicon substrate proximate to the main surface, the drain region being spaced apart from the source region; a first lightly doped region in a portion of the silicon substrate proximate to the main surface extending from the gate to the source region so that all of the source region is located within the first lightly doped region; a second lightly doped region in a portion of the silicon substrate proximate to the main surface extending from the gate to the drain region, wherein a length of the second lightly doped region is larger than a length of the drain region so that all of the drain region is located within the first lightly doped region, wherein the drain region, the source region, the first lightly doped region and the second lightly doped region have the same conductive type; a channel region being defined in a portion of the silicon substrate proximate to the main surface between the source region and the drain region, the channel region being at least partially beneath the gate; and an additional region along a sidewall of the gate, in direct contact with the main surface proximate to the channel region and disposed over the second lightly doped region between the gate and the drain region, the additional region being not in contact to the drain region and formed of a high-k material, wherein the additional region is present only on one side of the gate.