Small grain size, conformal aluminum interconnects and method for their formation
AssigneeMicron Technology, Inc.
InventorsWing-Cheong Gilbert Lai, Gurtej Singh Sandhu
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Abstract
A first layer of titanium nitride (TiN) is formed on a semiconductor structure, such as an interconnect via. Then, a second layer of TiN is formed on the first layer of TiN. The first layer of TiN is amorphous. The second layer of TiN is polycrystalline, having a mixed grain orientation. Finally, an aluminum film is formed on the second layer of titanium nitride. Optionally, a titanium silicide layer is formed on the semiconductor structure prior to the step of forming the first layer of titanium nitride. Interconnects formed according to the invention have polycrystalline aluminum films with grain sizes of approximately less than 0.25 microns.
Claims9
A method of fabricating an interconnect supported by a semiconductor structure, comprising:
- forming a first layer of titanium nitride on the semiconductor structure;
- forming a second layer of titanium nitride on the first layer of titanium nitride;
- and
- forming an aluminum film on the second layer of titanium nitride wherein the second layer of titanium nitride comprises a polycrystalline orientation that comprises a mixture of 1:1 of <111> and <200> oriented grains that are effective for forming an aluminum film of small grain size.
Dependencies are inferred from the claim text.