| 摘要 |
PURPOSE:To obtain an exposure light source for an aligner, as a substituting light source for an excimer laser oscillating at a specified wavelength, by applying a solid laser light source generating the second harmonic wave of a fundamental laser light having a specified wavelength and the laser light generated from second nonlinear crystal to an illumination light. CONSTITUTION:Second harmonic wave L2 obtained by supplying fundamental wave L1 whose wavelength is 1000nm or longer to nonlinear crystal 22A from an Nd:YAG laser light source 21 is supplied, as a pumping light, to a wavelength changeable laser light source 23, and a wavelength changeable laser light L3 is obtained. Second harmonic wave L4 is obtained by supplying the wavelength changeable laser light L3 to nonlinear crystal 22B. Fourth harmonic wave is obtained by supplying the second harmonic wave L4 to nonlinear crystal 22C, or third harmonic wave is obtained by supplying the wavelength changeable laser light L3 and the second harmonic wave L4 to the nonlinear crystal 22C at a specified angle. Thereby a laser light whose wavelength is 250nm or shorter is applied to an illumination light. |
