Back to results
US 8,575,752 B2Granted
Modulated deposition process for stress control in thick TiN films
AssigneeTexas Instruments Incorporated
InventorsGregory Charles Herdt, Joseph W. Buckfeller
Life of this patent
Estimating the term…
Abstract
A multi-layer TiN film with reduced tensile stress and discontinuous grain structure, and a method of fabricating the TiN film are disclosed. The TiN layers are formed by PVD or IMP in a nitrogen plasma. Tensile stress in a center layer of the film is reduced by increasing N2 gas flow to the nitrogen plasma, resulting in a Ti:N stoichiometry between 1:2.1 to 1:2.3. TiN films thicker than 40 nanometers without cracks are attained by the disclosed process.
Claims5
An integrated circuit (IC), comprising:
- a semiconductor substrate;
- and
- a multi-layer TiN film, including:
- a first TiN layer with a first grain structure formed on a top surface of said semiconductor substrate;
- a second TiN layer with a second grain structure and with less tensile stress than said first TiN layer formed on a top surface of said first TiN layer;
- and
- a third TiN layer with a third grain structure formed on a top surface of said second TiN layer, wherein:
- said first TiN layer is between 5 and 10 nanometers thick;
- said second TiN layer is greater than 20 nanometers thick;
- and
- said third TiN layer is between 5 and 10 nanometers thick.
8 more elements
An integrated circuit (IC), comprising:
- a semiconductor substrate;
- and
- a multi-layer TiN film, including:
- a first TiN layer with a first grain structure formed on a top surface of said semiconductor substrate;
- a second TiN layer with a second grain structure and with less tensile stress than said first TiN layer formed on a top surface of said first TiN layer;
- and
- a third TiN layer with a third grain structure formed on a top surface of said second TiN layer, in which:
- a Ti:N stoichiometry of said first TiN layer is between 1:1.05 and 1:1.15;
- a Ti:N stoichiometry of said second TiN layer is between 1:2.1 and 1:2.3;
- and
- a Ti:N stoichiometry of said third TiN layer is between 1:1.05 and 1:1.15.
8 more elements
Dependencies are inferred from the claim text.