US 6,204,102 B1 · Method of fabricating compound semiconductor devices using lift-off of insulating film

Abstract

A method of forming a gate electrode of a compound semiconductor device includes forming a first insulating film pattern having a first aperture, forming a second insulating film pattern having a second aperture consisting of inverse V-type on the first insulating film pattern, forming a T-type gate electrode by depositing a conductivity film on the entire structure, removing a second insulating film pattern, forming a insulating spacer on a pole sidewall by etching a first insulating film pattern, and forming an ohmic electrode of the source and drain by self-aligning method using T-type gate electrode as a mask. Thereby T-type gate electrode of materials such as refractory metals can be prevented to be deteriorate because of high annealing, as well as it is stably formed, by using an insulating film. Ohmic metal and gate electrodes formed by self-aligning method can be prevented an interconnection by forming an insulating film spacer between these electrodes.

Claims16

Dependent claims

A method of fabricating a semiconductor device comprising steps of:

a) preparing a semiconductor layer;
b) forming a first insulating film pattern having a first aperture which exposes a portion of said semiconductor layer;
c) forming a second insulating film pattern having a second aperture on said first insulating film pattern and a third insulating film pattern having a third aperture on the second insulating pattern, wherein said second and third apertures are connected with said first aperture, the width of said third aperture is wider than that of said first aperture, and the width of said second aperture is wider than that of said third aperture;
d) depositing a conductivity film on the entire structure after the step c), and forming a T-type gate electrode that touches said semiconductor layer, wherein said T-type gate electrode is formed with a conductive film and is deposited inside said first and second apertures;
e) removing said second insulating film;
and
f) forming an insulating spacer on a post of the conductive film by etching said first insulating film.

4 more elements

A method of fabricating a semiconductor device comprising steps of:

a) forming a first semiconductor layer;
b) forming a second semiconductor layer on the entire structure after said step a);
c) forming a first oxide film having a first aperture which exposes a portion of said second semiconductor layer;
d) forming a nitride film pattern having a second aperture and a second insulating film pattern having a third aperture, wherein said second and third apertures are connected with said first aperture, the width of said third aperture is wider than that of said first aperture, and the width of said second aperture is wider than that of said third aperture;
e) exposing a portion of said first semiconductor by removing the portion of said second semiconductor layer exposed by said first aperture;
f) depositing a conductive film on the entire structure after said step e), and firming a T-type gate electrode that touches the first semiconductor layer which is exposed in step c), wherein said T-type gate electrode is formed with a conductive film and is deposited inside said first and said second apertures;
g) removing said second oxide and nitride patterns;
and
h) forming an insulating spacer on a post of the conductive film by etching said first insulating film.

6 more elements

Dependencies are inferred from the claim text.

Method of fabricating compound semiconductor devices using lift-off of insulating film

Life of this patent

Method of fabricating compound semiconductor devices using lift-off of insulating film

Life of this patent

Abstract

Claims16