Macro- and micro-scale simulation of growth rate and composition in MOCVD of yttria-stabilized zirconia

Thermal barrier coatings produced by chemical vapor deposition

“…Since the thin film form of YSZ can reduce the overall electrical resistance, YSZ thin films have been synthesized by several methods including CVD [8 -12]. Table 1 4 and YCl 3 would require deposition temperatures higher than 1200 K and produce corrosive HCl by-products. Thus, these precursors will be limited to use for nonmetallic substrates.…”

“…Table 2 summarizes CVD conditions and several properties for YSZ intended for TBCs. Wahl et al [15] reported the use of Zr(thd) 4 and Y(thd) 3 precursors in a vertical hot-wall reactor at 900-1300 K and 1 kPa. The precursor vapors were separately carried by argon gas, and reacted with preheated oxygen.…”

“…Dubourdieu et al [16] employed a solid single-source delivery system to deposit YSZ films from Y(thd) 3 and Zr(thd) 4 precursors at 723 -1123 K and 0.40 kPa. The precursors mixed in the desired ratios were packed into a pyrex tube.…”

“…Fig. 1 shows YSZ films prepared from Zr(dpm) 4 and Y(dpm) 3 precursors at 1073 K and 0.8 kPa for 0.9 ks. The precursors were separately vaporized at 593 and 433 K, respectively, and carried by argon gas.…”

“…YSZ coatings exhibited the desirable nonequilibrium tetragonal t 0 phase with a strong (200) orientation. The PE-CVD coatings were prepared at 973 or 1173 K and 106.4 Pa using a microwave power about 1700 W. ZrCl 4 and Y(thd) 3 precursors were separately evaporated at 443 -503 K, where Y 2 O 3 contents varied from 3 to 4.3 mol%. Coatings obtained at 973 K consisted of fine and irregular aligned columns while those prepared at 1173 K exhibited welldeveloped columns.…”