| 摘要 |
<p>PROBLEM TO BE SOLVED: To simply and accurately cut a single crystal wafer at a surface having a desired crystal orientation and to reduce loss of a single crystal material by detecting the orientation of the crystal from a deviation of a reflected light of a laser beam from an emitted beam, and deciding a cutting direction. SOLUTION: An He-Ne laser beam (laser beam) 8 having about several mW and satisfactory directivity with a spreading angle of 3" or less is incident to a plane mirror 9, and position and direction of a laser beam oscillator 10 are regulated so that its reflected beam is returned to an emitting port 14. A single crystal ingot 12 is installed in a work holder 11 while the emitting direction of the beam 8 remains fixed, and the beam 8 is reflected on a crystal habit surfaces 5. The reflected beam is projected to a screen 13 parallel to a base 7, and an angle (θ) of the reflected beam and a position on the screen are measured. Here, a distance from the port 14 to the surface 5 is about 1m, theθis about 3 deg., it is regulated so that a deviation of a reflected beam spot 15 becomes at a position of about 10.5cm in a horizontal direction, and cut.</p> |
