J. Aarik et al., IN-SITU STUDY OF A STRONTIUM BETA-DIKETONATE PRECURSOR FOR THIN-FILM GROWTH BY ATOMIC LAYER EPITAXY, Journal of materials chemistry, 4(8), 1994, pp. 1239-1244
Precursor properties of Sr(thd)2 (thd = 2,2,6,6-tetramethyl heptane-3,
5-dione) have been investigated using in situ mass monitoring of thin
films during atomic layer epitaxy growth cycles. H2O and H2S were used
as the other source materials. The Sr(thd)2 source temperature, T(s),
significantly affects the growth rate. At T(S) = 240-270-degrees-C, a
decrease of growth rate and in some cases even etching of the grown f
ilm takes place. These phenomena can be explained by the decomposition
of Sr(thd)2, which also explains the dependence of the growth rate on
the reactor temperature, T(R), observed when T(S) < 240-degrees-C and
240 less-than-or-equal-to T(R)/degrees-C less-than-or-equal-to 400. T
he growth experiments were complemented and the conclusions supported
by separately studying (by mass spectrometry thermogravimetry, and dif
ferential thermal analysis) the thermal stability and fractionation of
the precursor.