MOS transistor formation
AssigneeAdvanced Micro Devices, Inc.
InventorTodd Lukanc
Life of this patent
Estimating the term…
Abstract
Semiconductor devices of different conductivity types with optimized gate electrodes are formed on a semiconductor substrate by replacing the initial gate electrode and, optionally, the underlying gate oxide layer. Embodiments include forming a first gate electrode on a gate oxide layer and replacing the gate electrode with a second gate electrode. Optionally, a second dielectric layer can be deposited in place of or in addition to the gate oxide layer prior to depositing the second gate electrode.
Claims20
A method of manufacturing a semiconductor device, which method comprises:
- forming a first dielectric layer on a substrate;
- forming a first gate electrode on the first dielectric layer, wherein the first gate electrode has an upper surface;
- depositing an insulating layer on the substrate to protect the substrate;
- removing the first gate electrode by selectively etching the first gate electrode with a reactive fluoride compound;
- forming a second dielectric layer on the first dielectric layer;
- and
- forming a second gate electrode in place of the first gate electrode.
The method according to claim 6, comprising depositing the second dielectric layer to a thickness of about 15 Å to about 100 Å.
The method according to 1, comprising forming the second gate electrode by depositing aluminum, copper, tungsten, titanium, gold, silver, or alloys thereof.
A method of forming a semiconductor structure, the method comprising:
- forming a gate oxide layer on a surface of a semiconductor substrate;
- forming a first gate electrode on the gate oxide layer;
- forming an insulating layer on the substrate to protect the substrate;
- removing the first gate electrode by selectively etching the first gate electrode with a reactive fluoride compound;
- removing the gate oxide layer;
- forming a dielectric layer on the substrate in place of the gate oxide layer;
- and
- forming a second gate electrode on the dielectric layer.
Dependencies are inferred from the claim text.