| 摘要 |
<p>Chemical vapor deposition of hafnium to form compounds on the surface of suitable substrates has various applications, based on the coherence and hardness of the coating. Such coatings can, for example, act as a diffusion barrier or as a hard surface for tools. In the past, it has been assumed that temperatures in the neighbourhood of 1200 to 1300 degrees C. were required to produce hafnium coatings by C.V.D. It has been found that by utilizing the lower halides of hafnium in the process, much lower temperatures can be used, in the neighbourhood of 900 degrees C. It has also been found that lower halides are most conveniently produced by a low temperature reaction between hafnium and halide compounds such as hydrogen chloride, hydrogen iodide, etc.</p> |
