Making a Multilayered Mask Without Requiring the Use of Selectively Etched Mask Materials
Original Publication Date: 1988-Sep-01
Included in the Prior Art Database: 2005-Feb-15
A method has been devised to protect one type of metal pattern from chemical attack, while chemically etching another metal during metal mask fabrication for semiconductor or packaging applications. Hydrogenated amorphous carbon, selectively adhered to only a portion of the mask, is used in the proposed procedure. Multilayer masks are conventionally used when it is desired to make masks with a fine line width on thick material. However, it is usually necessary to use different materials for each mask layer so that etchants of one layer do not attack the layer underneath. The proposal uses self-aligned selective deposition to make the desired layer chemically resistant to etchants, thereby providing a broad selection of both mask materials and chemicals suitable for etching the unprotected material. Metal X (e.g.