Sputter Joining of TiO2 / SiO2 Thin Film System

This paper describes the results of room temperature joining of TiO2 / SiO2 IRF by sputter deposition with a special emphasis of improvement of adherence at the interface. This multilayer system is designed to shield the infrared energy of solar spectrum by interference reflection. The abrasion resistance of the multilayer stacks was also estimated by the Haze value after the Taber abrasion test. It was found that the Haze values of TiO2 / SiO2 system showed over 20% after abrasion test, indicating poor adhesion at the interface. By introducing Al2O3 layer at the interface between SiO2 and TiO2, the haze value deceased to 1.9%. Transmission electron microscopic observation revealed distinct interface at TiO2 /SiO2, but amorphous continuous and indistinct interfaces of SiO2/ Al2O3 and TiO2 / Al2O3 were clearly found. These results can be explained in terms of chemical reactions at the interface at SiO2 / Al2O3 and Al2O3 /TiO2 by local heat evolution induced by energy deposition of sputtered particles.