Strontium titanate, deposition

Strontium titanate (SrTi03) has a large dielectric constant of 12, and a high refractive index with potential opto-electronic applications. It is deposited by MOCVD from titanium isopropoxide and a strontium beta-diketonate complex at 600-850°C and 5 Torr.t" " ... 

Fell, W. A., Wessels, B., Tonge, L., and Marks, T., Chemically Vapor Deposited Strontium Titanate Thin Films and Their Properties, Proc. 11th. Int. Conf. on CVD, (K. Spear and G. Cullens, eds.), pp. 148-154, Electrochem. Soc., Pennington, NJ 08534(1990)... 

Lehn, J.-M., Sauvage, J.-R, Ziessel, R., and Hilaire, L., Water photolysis by UV irradiation of rhodium loaded strontium titanate catalysts. Relation between catalytic activity and nature of the deposit from combined photolysis and ESCA studies, Isreal ]. Chem., 22,168,1982. 

Water Photolysis by UV Irradiation of Rhodium Loaded Strontium Titanate Catalysts. Relation Between Catalytic Activity and Nature of the Deposit from Combined Photolysis and ESCA Studies. Powdered catalysts used and the water photolysis efficiency is found to have a strong pH dependence. 399... 

Additional work on dielectrics includes deposition of silica, PABS (lead aluminum boron silicates), PLZT (lead lanthanum zirconium titanate) and BST (barium strontium titanate) on Si-Ti-Pt wafers (Figure 2). The wafer specimens were patterned with metal electrodes and electronic properties were characterized. 

Fig. 3 An epitaxial layer of strontium titanate was successfully deposited onto a MgO single crystal. The lower picture is a 5x magnification of the inset in the upper picture.

Barium titanate thin films can be deposited on various substances by treating with an aqueous solution containing barium salts and an alkanolamine-modifted titanate such as TYZOR TE (151). In a similar fashion, reaction of a tetraalkyl titanate with an alkah metal hydroxide, such as potassium hydroxide, gives oxyalkoxide derivatives (KTi O(OR) ), which can be further processed to give alkali metal titanate powders, films, and fibers (152—155). The fibers can be used as adsorbents for radioactive metals such as cesium, strontium, and uranium (156). 

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