System and method for integrated circuits with cylindrical gate structures

摘要

A device and method for integrated circuits with surrounding gate structures are disclosed. The device includes a semiconductor substrate and a fin structure on the semiconductor substrate. The fin structure is doped with a first conductivity type and includes a source region at one distal end and a drain region at the opposite distal end. The device further includes a gate structure overlying a channel region disposed between the source and drain regions of the fin structure. The fin structure has a rectangular cross-sectional bottom portion and an arched cross-sectional top portion. The arched cross-sectional top portion is semi-circular shaped and has a radius that is equal to or smaller than the height of the rectangular cross-sectional bottom portion. The source, drain, and the channel regions each are doped with dopants of the same polarity and the same concentration.

主权项

1. A transistor device comprising:
a semiconductor substrate; a fin structure protruding from the semiconductor substrate and extending in a first direction, the fin structure having a first type impurity and including a source region disposed at one end and a drain region disposed at the opposite end and a channel region disposed between the source region and the drain region; and a gate structure overlying the channel region; wherein the fin structure has a rectangular cross-section bottom portion having a width and a height measured in a second direction perpendicular to the first direction and an arched cross-section top portion, wherein a maximum distance measured in the second direction between opposite sides of the arched cross-section top portion is equal to the width of the rectangular cross-section bottom portion, and wherein the source, drain, and channel regions each are doped with dopants of a same polarity and a same concentration.