New alloy system based on corundum structured oxides fabricated by Mist-CVD technique

Innovative electric devices have been derived from new alloy systems for example AlAs-GaAs-InAs, AlP-GaP-AlAs-GaAs and AlN-GaN-InN. These alloy systems are consisted of binary compounds of same crystal structure and small lattice mismatches among them. We will propose a new alloy system based on corundum structured crystals: alpha-Al2O3, Ga2O3, In2O3, Fe2O3, Cr2O3, V2O3, Ti2O3, and Rh2O3. The optical band gap can be tuned from 3.7 to 9.0 eV by making of Al2O3-Ga2O3-In2O3 alloy. On the other hand transition metal oxides have many physical functions. Fe2O3 is a weak-ferromagnetism, Cr2O3 is a Mott insulator showing magnetoelectric effect, V2O3 and Ti2O3 showing metal-to-insulator transition and metal-to-semiconductor transition, respectively. Rh2O3 is not only showing electrochromic but also p-type semiconductor with a band gap of 1.2 eV. These can provide many physical functions to the alloy system of Al2O3-Ga2O3-In2O3. In this seminar, I will talk about this new alloy system and the new fabrication method of Mist-CVD technique which was originally developed by our laboratory.