The deposition of ZrO2, Y2O3 or Al2O3 from the precursors Zr(tmhd)(4), Y(tm
hd)(3) and Al(acac)(3) is investigated in this paper. Chemical vapor deposi
tion (CVD) experiments were carried out in the temperature range 500-1100 K
at pressures between 1000 and 4000 Pa in different reactors with different
temperature fields. In addition. the temperature gradient between substrat
e and gas was changed from negative to positive values in order to measure
the influence of thermophoresis effects. The deposition rate j in the low t
emperature range can be described by an Arrhenius law, j=k exp(-E/RT), wher
eby the pre-exponential factor k and the activation energy E depend on the
temperature field. It is experimentally found that the effect of a changing
activation energy is partly compensated by a changing pre-exponential fact
or in the same direction (compensation effect). In the case of Al2O3-deposi
tion, thermophoresis effects were measured. (C) 2000 Elsevier Science S.A.
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