| 摘要 |
PURPOSE:To hold the exposure amount of the periphery of a wafer constant by providing a rotating mechanism for rotating the wafer coated with resist, a light radiating mechanism, an illuminance monitor, and comparing means for comparing a signal from the monitor with a reference illuminance signal, and controlling the rotating time of the rotating mechanism on the basis of the compared result. CONSTITUTION:In a wafer 1 periphery exposure, light from a mercury lamp L is guided by a light guide fiber 4, and the periphery 1p of the wafer 1 rotating by a rotary stage 6 is irradiated with the light. In order to hold exposure amount W constant t may be so controlled as to become t=t0(I0/I), where I0 is reference illuminance, I is monitoring illuminance, t0 is rotating time necessary at the time of the reference illuminance, and t is rotating time to be controlled. If the illuminance I is reduced due to certain reason, a control signal is so sent from a controller 10 to a stage driving motor 9 as to increase the rotating time t. Thus, even if the illuminance is reduced in an ageing manner, the exposure amount can be held necessarily constant. In the drawing, numeral 7 denotes an illuminance monitor, and numeral 8 denotes a comparator. |
