Semiconductor manufacturing method using a high extinction coefficient dielectric photomask

Abstract

A method is provided for manufacturing a semiconductor with fewer steps and minimized variation in the etching process by using SiON as a bottom antireflective (BARC) layer and hard mask in conjunction with a thin photoresist layer. In one embodiment, an etch-stop layer is deposited on a semiconductor substrate, a dielectric layer is deposited on top of the etch-stop layer, and a BARC is deposited on top of the dielectric layer. The BARC is deposited by PECVD to enrich the BARC with semiconductor material to increase the extinction coefficient of the BARC so its thickness can be reduced. A photoresist layer with a thickness less than the thickness of the BARC is then deposited on top of the BARC. The photoresist is then patterned, photolithographically processed, developed, and removed. The BARC is then etched away in the pattern developed on the photoresist and the photoresist is then removed. The BARC is then used as a mask for the etching of the dielectric layer. A conductive material is deposited over the BARC and the dielectric layer and is subsequently removed in the process of polishing the conductive material without requiring a separate BARC removal step.

Dependencies are inferred from the claim text.