| 摘要 |
PURPOSE:To produce a relatively large single crystal by a method wherein the long span or the short span of an elliptic projection of an energy beam on an object is inclined in relation with the direction of beam scan. CONSTITUTION:An energy beam with an elliptic cross section is used, with the long span (b) or the short span (a) forming an angle beta or alpha with the scanning direction in an laser-annealing process for a polycrystalline Si film. By this, a single crystal 41 is created at the central part, flanked by polycrystalline Si bands 42 and 43. When a next scan is slightly displaced upward as shown with B, the width of the central single crystal 51 almost doubles, while the side bands 52 and 53 remain almost unchanged. The polycrystalline section 54 may grow a little into the central single crystal 51, the growth is small and further decelerated as scans are repeated. Thus, repetition of scans results in the formation of a wide single crystal. |
