| 摘要 |
PURPOSE:To remove the blur of the window of a reaction cell, and moreover to enable to control a chemical reaction having high selectivity by a method wherein excitation of an oscillation is performed according to infrared laser, and then molecules excited to the oscillation are excited to be dissolved according to ultraviolet laser. CONSTITUTION:SiH4 gas diluted by N2 or Ar gas is introduced in a reaction cell 31 through port openings 36, 37. Then a CO2 laser beam (infrared wavelength variable laser) 35 is introduced in parallel with the surface of an Si wafer 32. When the laser beam is formed in a sheet type using a cylindrical lens, SiH4 molecules in the neighborhood of the surface of the substrate are excited to oscillate. Then by irradiating perpendicularly by a dye laser 34 to the surface of the substrate, only excited SiH4 to the oscillation is dissolved to generate atom type Si, and an a-Si thin film is formed. Because the reaction thereof is generated only in the neighborhood of the surface of the substrate 32, the blur of a window 34 is not generated. Moreover because only the molecules selectively excited according to the oscillation level are dissolved, selectivity of the oscillation is favorable. |
