The Organometallic Chemical Vapor Deposition of Transition Metal Carbides: The Use of Homoleptic Alkyls
Tóm tắt
The organometallic chemical vapor deposition (OMCVD) of transition metal carbides (M = Ti, Zr, Hf, and Cr) from tetraneopentyl-metal precursors has been carried out. Metal carbides can be deposited on Si, Al2O3, and stainless steel substrates from M[CH2C(CH3)3]4 at temperatures in the range of 300 to 750 °C and pressures from 10−2 to 10−4 Torr. Thin films have also been grown using a carrier gas (Ar, H2). The effects of variation of the metal center, deposition conditions, and reactor design on the resulting material have been examined by SEM, XPS, XRD, ERD and AES. Hydrocarbon fragments generated in the deposition chamber have been studied by in-situ mass spectrometry. Complimentary studies examining the UHV surface decomposition of Zr[CH2C(CH3)3]4 have allowed for a better understanding of the mechanism leading to film growth.
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