Process for low k organic dielectric film etch
AssigneeUnited Microelectronics Corp.
InventorsHsien-Ta Chung, Chan-Lon Yang, Tong-Yu Chen, Tri-Rung Yew
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Abstract
A simplified method is disclosed for etching low k organic dielectric film. A substrate is provided with a hardmask layer and low k organic dielectric layer formed thereon in which hardmask layer is on the dielectric layer. A layer of photoresist is formed on the hardmask layer and imaged with a pattern by exposure through a dark field mask. As a key step, the pattern is transferred into the hardmask layer by dry etching and then the photoresist is stripped in-situ. Then, the interconnect is formed by using dry etching the low k organic dielectric layer using the hardmask layer as a mask, and readying it for the next semiconductor process.
Claims18
A method for etching low k organic dielectric film, said process comprising:
- providing a substrate having a low k organic dielectric layer on said substrate and a hardmask layer on said low k organic dielectric layer;
- forming a photoresist layer on said hardmask layer;
- patterning said photoresist layer by exposing said photoresist layer using a dark field photo mask;
- etching said hardmask layer using said photoresist layer as a mask thereby transferring said pattern in said photoresist layer into said low k organic dielectric layer;
- in-situ removing said photoresist layer;
- and
- etching said low k organic dielectric layer using said hardmask layer as a mask thereby transferring said pattern on said hardmask layer into said low k organic dielectric layer.
A method for forming damascene pattern employing low k organic dielectric films as insulation layer, said method comprising:
- providing a substrate having a low k organic dielectric layer on said substrate and a cap layer on said low k organic dielectric layer;
- forming a photoresist layer on said cap layer;
- patterning said photoresist layer by exposing said photoresist layer using a dark field photo mask;
- etching said cap layer using said photoresist layer as a mask thereby transferring said pattern in said photoresist layer into said cap layer;
- in-situ removing said photoresist layer;
- etching said low k organic dielectric layer using said cap layer as a mask thereby transferring said pattern on said cap layer into said low k organic dielectric layer;
- depositing a metal layer;
- and
- etching back excess said metal layer by using chemical mechanical polishing method.
A method for forming dual damascene pattern employing low k organic dielectric films as insulation layer, said method comprising:
- providing a substrate having a first low k organic dielectric layer on said substrate, a stop layer on said first low k organic dielectric layer, a second low k organic dielectric layer, and a cap layer on said second low k organic dielectric layer;
- forming a first photoresist layer on said cap layer;
- hole patterning said first photoresist layer by exposing said first photoresist layer using a dark field photo mask;
- etching said cap layer using said first photoresist layer as a mask thereby transferring said hole pattern in said first photoresist layer into said cap layer;
- in-situ removing said first photoresist layer;
- etching said second low k organic dielectric layer, said stop layer, and said first low k organic dielectric layer using said cap layer as a mask thereby transferring said hole pattern on said cap layer into said first and second low k organic dielectric layer;
- forming a second photoresist layer on said cap layer;
- line patterning said second photoresist layer by exposing said second photoresist layer using a dark field photo mask;
- etching said cap layer using said second photoresist layer as a mask thereby transferring said line pattern in said second photoresist layer into said cap layer;
- in-situ removing said second photoresist layer;
- etching said second low k organic dielectric layer using said cap layer as a mask thereby transferring said line pattern on said cap layer into said second low k organic dielectric layer;
- depositing a metal layer;
- and
- etching back excess said metal layer by using chemical mechanical polishing method.
Dependencies are inferred from the claim text.