| 摘要 |
PURPOSE:To improve the adhesiveness between a polyimide (PI) film and photoresist at the time of wet etching by providing a specific PI boundary face reforming film on the PI film and subjecting the photoresist to exposing and developing after coating, then etching the PI. CONSTITUTION:The film of the PI consisting of arom. diamine which is 1mol. 4,4'-diamino diphenyl ether and tetracarboxylic anhydride which is 1mol one kind of pyromellitic acid anhydride 3,3',4,4'-biphenyl tetracarboxylic dianhydride or the mixture composed thereof is formed as the PI boundary face reforming film on the PI film 3 (1 is a substrate, 2 is a wiring) and after the photoresist 5 is coated thereon, the photoresist is subjected to exposing and developing, then the PI film 3 is etched. The PI is preferably low thermally expandable PI having <=3X10<-6>K<-1> coefft. of thermal expansion and the photoresist 5 is preferably a cyclized rubber type negative resist. Hydrazine hydrate, etc., are used for an etching agent and the etching rate of the boundary face reforming film 4 is preferably 1/2-2 times the etching rate of the PI film 3. The extremely fine patterns of the inter-layer insulating films of a VLSI are thereby formed. |
