Thin film transistor

摘要

Disclosed herein are thin film transistors (TFTs) and techniques for fabricating TFTs. A major plane of the gate electrode of the TFT may be vertically oriented with respect to a horizontal layer of polysilicon in which the TFT resides. An interface between the gate electrode and gate dielectric may be vertically oriented with respect to a horizontal layer of polysilicon in which the TFT resides. The TFT may have a channel width that is defined by a thickness of the horizontal layer of polysilicon. The TFT may be formed by etching a hole in a layer of polysilicon. Then, a gate electrode and gate dielectric may be formed in the hole by depositing layers of dielectric and conductor material on the sidewall. The body may be formed in the horizontal layer of polysilicon outside the hole.

主权项

1. A device comprising:
a semiconductor substrate that has a major surface that extends in a horizontal plane; and a horizontal layer comprising conductor material above the semiconductor substrate, wherein the horizontal layer has a major surface that extends in the horizontal plane; a thin film transistor (TFT) in the horizontal layer, the TFT including:
a gate electrode;a gate dielectric surrounding the gate electrode, an interface between the gate electrode and gate dielectric extending vertically with respect to the horizontal plane, wherein the conductor material of the horizontal layer surrounds the gate dielectric;a body, a source, and a drain that reside in the conductor material of the horizontal layer;wherein the body is adjacent to the gate dielectric, an interface between the gate dielectric and the body extending vertically with respect to the horizontal plane, the body having a first end and a second end;wherein the source is at the first end of the body, wherein the source is in direct electrical contact with a first region of the conductor material in the horizontal layer; andwherein the drain is at the second end of the body, wherein the drain is in direct electrical contact with a second region of the conductor material in the horizontal layer, wherein the body comprises a channel that extends from the source to the drain.