| 摘要 |
PURPOSE:To obtain magnesia spinel layers of good crystallinity, by a method wherein an Si substrate i surface-etched with hydrogen fluoride acid and rinses before vapor-phase growth and then immersed in pure water at least 4 hours or more. CONSTITUTION:The conventional treatments (1)-(9) are carried out before pure-water boiling (13); after that process, the part of an Si substrate surface where an Si film on the etching Si substrate has been formed is etched (10) in surface with hydrogen fluoride acid, thus removing the Si dioxide film. The substrate is then subjected to pure-water rinse (11) and pure-water immersion (12). The characteristic of a formed spinnel layer markedly varies with the time of this pure-watrer immersion. After pure-water boiling (13), the processes of the Si substrate finish with drying with hot nitrogen gas (14). Then, a magnesia spinel layer is formed. |
