Oxide epitaxial lift-off (OELO) has been successfully accomplished for thin
single layer films of strontium titanate and multilayer films of strontium
titanate and superconducting yttrium barium copper oxide (YBCO). The techn
ique employs a YBCO release layer to separate the films from the growth sub
strate. The critical development was the use of a polymer support layer whi
ch retains sufficient compliance after curing to permit stress relaxation o
f the oxide film in such a way as to prevent cracking. Multilayer lift-off
had the additional necessity of encapsulating the YBCO device layer. This w
as accomplished by alternately depositing layers of strontium titanate and
YBCO. Layer thicknesses were optimized to compensate for the resulting thro
ugh-thickness stress gradient which developed due to thermal expansion diff
erences.