Effect of yttria doping on the optical properties of yttria stabilized zirconia thin films deposited by RF plasma enhanced MOCVD

Zirconium oxide is a refractory ceramic. It has technologically important applications in field of optics, microelectronics, in solid oxide fuel cell, as wear resistant and thermal barrier coating. ZrO2 occurs naturally in monoclinic form at room temperature and undergoes transformation to tetragonal phase at 1170℃ and to cubic phase at 2370℃. Phase change from tetragonal to monoclinic is destructive as it is accompanied by a 4% volume increase leading to cracking of the material. ZrO2 is doped with dopants like Y2O3, MgO, CaO to stabilize tetragonal and cubic phases at room temperature. ZrO2 doped with 3-5 mol% Y2O3 results in partially stabilized zirconia (PSZ). Doping ZrO2 with 8 mol% Y2O3 stabilizes ZrO2 in cubic phase known as yttria stabilized zirconia (YSZ)