In a joint program between the University of Tennessee Spare Institute (UTS
I) and Oak Ridge National Laboratory (ORNL), thin films of lanthanum alumin
ate (LAO) were formed on (100) strontium titanate (STO) single crystals and
on biaxially textured nickel by dip coating from sol-gel precursors and th
en annealing. XRD texture measurements were used to evaluate coating parame
ters including substrate withdrawal speed, degree of hydrolysis, and therma
l processing temperature, duration, and atmosphere. LAO films on the order
of 1000 thick showed 100% biaxial epitaxy on STO single crystals but only a
bout 50% in-plane epitaxy on nickel. An increase in substrate withdrawal ve
locity resulted in thicker films. On STO film texture degraded with increas
ed film thickness, but on nickel this effect was not noted, being obscured
as a result of the rather poor and variable texture of the nickel substrate
used. LAO on STO texture was improved by increases, within the ranges inve
stigated, in the degree of hydrolysis, and in the thermal processing time,
temperature, and oxygen concentration. No impediments to production scaleup
were found.