| 摘要 |
PURPOSE:To form a thin nitride film having a phase stable at high temp. on the surface of a substrate by immersing the substrate in a nitrogen medium and irradiating pulsed laser beams to the substrate surface through the medium to react the surface with nitrogen. CONSTITUTION:A substrate 4 to be nitrided is mounted on a table 5 in a liq. nitrogen container 2, and pulsed laser beams are irradiated to the substrate 4 surface from a laser beam generator 1 through liq. nitrogen 3. The pulsed laser beams are selected so that they pass through the nitrogen 3, and for example, the wavelengths are regulated to about 0.4-11mum. By irradiating laser beams for a short time, the temp. of the substrate 4 surface rises at a very high rising rate, the surface is melted and reacts with liq. nitrogen 3 contacting with the surface, and nitride is formed from the surface toward the interior. The reacted part cools by self-diffusion of heat and is kept at low temp. by the surrounding liq. nitrogen 3, and the cooling is accelerated to rapidly cool the reacted part. |
