Ultra-high vacuum CVD

For instance, a dip-coating technique can be used to prepare GaN films from either [Ga(N3)3]o= or the base-stabilized species . A unique azide that contains no carbon or hydrogen is [Cl2GaN3]3. It can be used to form GaN under ultra high vacuum CVD conditions . A related derivative, monomeric Cl2GaN3-NMe3, has a higher vapor pressure and can be used to form pure GaN (1-2 atom % carbon and chlorine) more effectively ... 

When pressure is used to control the deposition process, CVD can be classified into three categories, namely atmospheric-pressure CVD, low-pressure CVD (i.e. <1 Torr) or ultra-high vacuum CVD (i.e. 10 3 Torr) [10], Pressure has a considerable effect on the deposition rate and quality of the finished products, in terms of coating thickness uniformity. Detailed impacts of the pressure control are discussed in Chapter 4. 

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