Semiconductor device and method of forming junction enhanced trench power MOSFET having gate structure embedded within trench

摘要

A semiconductor device has a substrate and trench formed partially through the substrate. A drain region is formed in the substrate as a second surface of the substrate. An epitaxial region is formed in the substrate over the drain region. A vertical drift region is formed along a sidewall of the trench. An insulating material is deposited within the trench. A channel region is formed along the sidewall of the trench above the insulating material. The channel region is separated from the insulating material. A gate structure is formed within the trench adjacent to the channel region. The gate structure includes an insulating layer formed along the sidewall of the trench adjacent to the channel region and polysilicon layer formed within the trench over the insulating layer. A source region is formed in a first surface of the substrate contacting the channel region.

主权项

1. A method of making a semiconductor device, comprising:
providing a substrate; forming a trench partially through the substrate; forming a vertical drift region along a sidewall of the trench; depositing an insulating material within the trench; forming a first insulating layer in the trench over the insulating material; forming a channel region along the sidewall of the trench while the first insulating layer inhibits formation of the channel region along a portion of the sidewall of the trench above the insulating material; removing the first insulating layer; forming a gate structure within the trench on the insulating material; and forming a source region in a first surface of the substrate contacting the channel region.