| 摘要 |
PURPOSE:To obtain a thin film multilayer substrate with superior adhesion characteristics between insulating layers by placing an adhesion layer consisting of light-sensitive Si group polyimide between low thermal-expansion polyimide layers. CONSTITUTION:After the RIE etching process it is desirable to apply light- sensitive Si group polyimide 9 with the film thickness of approx. 10mum so as to eliminate an adhesion layer 2, with the thickness remaining to make it possible to maintain the adhesion characteristics to the next layer of low thermal- expansion polyimide 1 and not to generate a large residual stress, namely, 4mum. After that, the light-sensitive Si polyimide 9 is exposed and developed to open a hole 3, undergoes the completely imidized bake with two kinds being unified to one. Then, when the polyimide undergoes the RIE etching with O2 gas, the surface layer of the light-sensitive Si group polyimide 9 is etched a little, remaining as the adhesion layer 2, and a via-hole 1 is formed, with a low thermal-expansion polyimide layer 2 being selectively etched. |
