Method for Producing Gradually Tapered Openings in Multilayer Dielectrics
Original Publication Date: 1987-Apr-01
Included in the Prior Art Database: 2005-Feb-01
The construction of multilayer dielectrics with various openings sometimes results in steepwall profiles which can cause subsequent problems in production. This occurs with the use of photolithography to pattern circuitry on the dielectric layers because photoresist does not cover steep walls very well and often breaks down during etching, resulting in voids in the circuitry. These steep wall-related problems can be eliminated by constructing multilayer dielectrics with tapered openings by using successively smaller openings in the following manner. Fig. 1 shows a cross section of a conventionally constructed structure with all the layers having holes of the same size and shape. Fig. 2 is the representation of a tapered construction with the bottom layer 1 having the largest opening and layer 2 the next largest opening, etc.