Introduction of metal impurity to change workfunction of conductive electrodes
US7750418B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 2008 |
| Grant date | Jul 6, 2010 |
| Priority date | — |
| Expiry date | Jul 29, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/038
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Semiconductor structures, such as, for example, field effect transistors (FETs) and/or metal-oxide-semiconductor capacitor (MOSCAPs), are provided in which the workfunction of a conductive electrode stack is changed by introducing metal impurities into a metal-containing material layer which, together with a conductive electrode, is present in the electrode stack. The choice of metal impurities depends on whether the electrode is to have an n-type workfunction or a p-type workfunction. The present invention also provides a method of fabricating such semiconductor structures. The introduction of metal impurities can be achieved by codeposition of a layer containing both a metal-containing material and workfunction altering metal impurities, forming a stack in which a layer of metal impurities is present between layers of a metal-containing material, or by forming a material layer including the metal impurities above and/or below a metal-containing material and then heating the structure so that the metal impurities are introduced into the metal-containing material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.