Back to results
US 2015/0214054 A1Published application
Method of Forming Copper Sulfide Film for Reducing Cu Oxidization and Loss
AssigneeMacronix International Co., Ltd.
InventorsZusing Yang, Hong-Ji Lee
Life of this patent
Estimating the term…
Abstract
Effects of copper oxide formation in semiconductor manufacture are mitigated by etching with sulfide plasmas. The plasmas form protective copper sulfide films on copper surfaces and prevent copper oxide formation. When copper oxide formation does occur, the sulfide plasmas are able to transform the copper oxide into acceptable or more conductive copper compounds. Non-oxide copper compounds are removed using clear wet strips.
Claims20
A method of semiconductor manufacture, comprising:
- providing a semiconductor stack on a substrate to include a first intermetal dielectric (IMD-1) layer, a copper (Cu) layer in the IMD-1 layer, a silicon nitride (SiN) layer, and a second intermetal dielectric (IMD-2) layer;
- forming an opening that exposes at least a portion of an upper surface of the Cu layer;
- contacting the exposed portion of the Cu layer with a sulfide plasma, thereby causing a film including copper sulfide to form on the upper surface of the Cu layer.
The method as set forth in clam 1, wherein a thickness of the film ranges from about 1 nm to about 10 nm.
Dependencies are inferred from the claim text.