Growth of Aluminum Nitride on Porous Alumina and Silica through Separate Saturated Gas-Solid Reactions of Trimethylaluminum and Ammonia

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• 作者：Riikka L. Puurunen ; Andrew Root ; Priit Sarv ; Minna M. Viitanen ; Hidde H. Brongersma ; Marina Lindblad ; and A. Outi I. Krause
• 刊名：Chemistry of Materials
• 出版年：2002
• 出版时间：February 2002
• 年：2002
• 卷：14
• 期：2
• 页码：720 - 729
• 全文大小：135K
• 年卷期：v.14,no.2(February 2002)
• ISSN：1520-5002

文摘

Aluminum nitride-type species were prepared on porous alumina and silica by repeatedseparate, saturated reactions of gaseous trimethylaluminum (TMA) and ammonia with solidsubstrates. Reaction cycles of TMA at 423 K and ammonia at 823 K were performed up tosix times. Growth per cycle was on average 2.4 AlN units/nm², but it increased slightly withthe number of reaction cycles. The amount of hydrogen present in NH_x groups increasedwith the increasing number of reaction cycles. AlN₄ units were observed by ²⁷Al NMR onalumina, but the AlN remained amorphous to X-ray diffraction. Scanning electron microscopycombined with energy-dispersive X-ray spectroscopy revealed that the AlN-type species werespread out evenly on the surface of the particles. TMA reacted with equal probability withthe still-exposed silica and the AlN-type species present on the surface, as shown by low-energy ion scattering. ²⁹Si and ²⁷Al NMR suggested that transition from the oxide substratesto aluminum nitride occurred through silicon oxynitride for the silica substrate and throughaluminum oxynitride for both substrates.