Kl. Saenger et al., Oxygen stoichiometry in PdOx and PdOx/Pt electrode layers during processing of ferroelectric and high-epsilon perovskites, J MATER RES, 15(4), 2000, pp. 961-966
High-epsilon (HE) and ferroelectric (FE) perovskites such as (Ba,Sr)TiO3 an
d SrBi2Ta2O9 are attracting substantial interest for use in dynamic random-
access memory and nonvolatile memory. In this paper, we describe how an eas
ily decomposable PdO bottom electrode layer may be used as a marker for pos
sible HE/FE damage induced by exposure to reducing environments. Oxygen los
s from PdO films with and without a HE/FE overlayer was monitored by in sit
u x-ray diffraction during heating in an inert ambient. Additional measurem
ents were performed on PdO films in contact with Pt underlayers. A Pt under
layer was found to reduce the temperature of oxygen release from PdO, sugge
sting that it may be possible to custom-design PdO-based oxygen sources wit
h specific oxygen release characteristics to resupply the HE/FE with oxygen
lost during processing.