| 摘要 |
The present invention relates to a process of producing a porous layer structure on a heterogeneous polycrystalline substrate, comprising the following steps:
(i) providing a heterogeneous polycrystalline substrate having at least two regions with different chemical-physical properties,
(ii) conducting a selective etching process on said polycrystalline substrate, resulting in etched regions corresponding to one of the at least two regions of said substrate and non-etched regions corresponding to the other one of said at least two regions of said substrate,
(iii) covering the entire surface of the substrate with an insulating material, thus creating an insulating layer on said substrate,
(iv) polishing the surface of the substrate to such an extent that the non-etched regions of step (ii) are exposed,
(v) depositing microstructures on said non-etched regions till the growth of the microstructures starts narrowing their cavities formed between adjacently growing microstructures and, thus sealing the openings of said cavities, and
(vi) repeating successively above steps (iii), (iv) and (v) in a loop process till a desired height of the microstructures is reached, thereby obtaining a porous layer structure on said heterogeneous polycrystalline substrate. |
