I think it depends on the quality of porous alumina. Such systems are used as a material for silicon carbide - also quite complex material.

Hi Zhao, problem with AAO templates for high temperature deposition is usually the warping and fracture formation. Plus, MOCVD growth is not sensitive to where the material is deposited so unless you grow an ultrathin film it can clog up the pores. Good luck!

Thanks Lev and Giray. I acutally want to use AAO as a hard mask of GaN growth in MOCVD. But after detailed discussion, the nanostructure of AAO may not help to minimize the loading effect. So we will design some micrometer level patterns instead of AAO for the growth.