Forming MOSFET structures with work function modification

Patent metadata

Field	Value
Publication number	US-10147725-B2
Application number	US-201514968134-A
Country	US
Kind code	B2
Filing date	Dec 14, 2015
Priority date	Nov 6, 2015
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

A method of making a semiconductor device comprises forming a first channel region comprising a first channel region material and a second channel region comprising a second channel region material; disposing a gate dielectric on the first channel region and second channel region; depositing a work function modifying material on the gate dielectric; disposing a mask over the work function modifying material deposited on the gate dielectric disposed on the first channel region; removing the work function modifying material from the unmasked gate dielectric disposed on the second channel region; removing the mask from the work function modifying material deposited on the gate dielectric disposed on the first channel region; forming a first gate electrode on the work function modifying material deposited on the first channel region and forming a second gate electrode on the gate dielectric disposed on the second channel region.

First claim

What is claimed is:

1. A method of making a semiconductor device comprising:
forming a first channel region of the device comprising a first channel region material and a second channel region of the device comprising a second channel region material;
disposing a gate dielectric on the first channel region and second channel region;
depositing a work function modifying material such that the work function modifying material is in contact with the gate dielectric disposed on the first channel region and the second channel region;
disposing a mask over the work function modifying material deposited on the gate dielectric disposed on the first channel region;
removing the work function modifying material from the unmasked gate dielectric disposed on the second channel region;
removing the mask from the work function modifying material deposited on the gate dielectric disposed on the first channel region;
forming a first gate electrode on the work function modifying material deposited on the first channel region and forming a second gate electrode on the gate dielectric disposed on the second channel region; wherein:
the first gate electrode and the second gate electrode comprise the same single work function material;

forming an insulator layer between the first channel region and the second channel region, wherein a first portion of the insulator layer includes the work function material and a second portion of the insulator layer includes the work function material and the work function modifying material.

2. The method of claim 1 , wherein the first channel region material has a valence band edge that is dissimilar from a valence band edge of the second channel region material.

3. The method of claim 1 , wherein the first channel region material has a conduction band edge that is dissimilar from a conduction band edge of the second channel region material.

4. The method of claim 1 , wherein the work function modifying material is lanthanum oxide.

5. The method of claim 1 , wherein the insulator layer does not extend into a horizontal insulator layer.

6. The method of claim 1 , wherein the insulator layer extends upward from the horizontal insulator layer.

7. The method of claim 1 , wherein the first channel region and the second channel region extends through the horizontal insulator layer.

Assignees

• IBM

Inventors

• Bao Ruqiang
• Karve Gauri
• Liu Derrick
• Robison Robert R
• Tsutsui Gen
• Vega Reinaldo A
• Watanabe Koji

Classifications

• H10P14/69396

  the material containing at least one rare earth metal element, e.g. oxides of lanthanides, scandium or yttrium · CPC title

• H01L29/4958

  Electricity · mapped topic

• H01L29/16

  Electricity · mapped topic

• H01L27/0922 Primary

  Electricity · mapped topic

• H01L29/401

  Electricity · mapped topic