Vertical thin film transistor

Abstract

A thin film transistor includes a first insulating layer and a first conductive layer formed on a semiconductor substrate, a second insulating layer, a second conductive layer and a third insulating layer sequentially formed on the first conductive layer, a contact hole formed in the second insulating layer, second conductive layer and third insulating layer, a gate insulating layer formed along the sidewall of the contact hole, and a third conductive layer formed on the contact hole formed with the gate insulating layer thereon and surface of the third insulating layer to be used as a channel region and a source region by implanting an impurity, in which a drain region, a gate electrode and the source region are stacked, or vertically aligned on the substrate to allow a cell to occupy a small area for accomplishing high packing density of the cell and permit the gate electrode to encircle the channel region for improving a characteristic of the transistor, thereby stabilizing the cell.

Dependencies are inferred from the claim text.