| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress deformation of a mask due to thermal energy. <P>SOLUTION: As an illumination means for irradiating the illumination area of a semiconductor wafer 18 and a mask 40 with light emitted from a light emitting diode LD; the light emitting diode LD, and a lighting control circuit for lighting the light emitting diode LD intermittently, are provided. In order to light the light emitting diode LD only when it is required, instant stroboscopic light emission of the light emitting diode LD is carried out. Since the mask 40 is not always irradiated with light; impact of thermal energy imparted to the mask 40 becomes very small, and deformation of the mask 40 can be suppressed. <P>COPYRIGHT: (C)2008,JPO&INPIT |
