Popis: |
Examples of chemical control in CVD of metallic and ceramic films are highlighted. Specific attention is paid to the complexity of precursor design. The effect of reactor environment on growth chemistry is investigated. Examples where reducing or oxidizing atmospheres provide a high level of control over deposit composition are outlined. The system examined centers on yttrium and yttria. These materials are, in general, desired less for their optical or electronic properties and more for their structural properties. Thus, the rigid purity demands of the microelectronics industry are somewhat relaxed. Nevertheless, critical attention must be paid to the issues of vapor pressure and decomposition profile. Where sufficient data is available to justify it, some explaination of the issues relevent to vapor pressure is presented. |