| 摘要 |
<p>PURPOSE:To rapidly and effectively obtain desired data in PL photoevaluation by providing a lambda/4 wavelength plate for varying the polarizing state of a laser light at the laser light incident side of a microscope, and varying the quantity of light which arrives at a sample surface by continuously altering the polarizing state. CONSTITUTION:A linearly polarized laser light 11 becomes circularly or elliptically polarized light by a lambda/4 wavelength plate 25, incident to 45 deg. mirror 13, and is reflected on the surface of a sample 15 at a predetermined reflectivity. The plate 25 is regulated (rotated), i.e., applied with phase difference to continuously regulate the quantity of light which arrives at the sample surface. A PL light 16 generated from the sample 15 by an exciting laser light 11 is fed by a full- reflecting mirror 17 to a spectral unit, and a wavelength-intensity curve is drawn on a plotter 23. Since the plate is generally formed for the specific wavelength light, when the laser light is oscillated by a YAG laser, lambda/4 wavelength plate is disposed at the incident light side of a microscope 24, observed at a predetermined position on the wafer 15 to decide the propriety of the wafer.</p> |
