Exposure device

Abstract

Abstract PURPOSE:To accurately control the exposure amount by intercepting by a shutter means the laser in the early stage of the laser oscillation which has a large inter-pulse output deviation, and using as the illumination light for exposure only the laser after that the inter-pulse output of which has become stable. CONSTITUTION:A pulse laser oscillated from an excimer laser light source 10 enters a beam splitter 12, by which it is divided into an illumination light for exposure penetrating the beam splitter 12 and a partially reflected light for detecting the pulse output. The reflected light enters a first detector 14, detects the pulse intensity for each one pulse, and transmits this to a control section 16 thereby detecting the output strength deviation among pulses. The light having penetrated the beam splitter 12 enters a shutter 18. The shutter 18 is closed to intercept the laser light till the inter-pulse output deviation becomes a predetermined allowable value or less, and when it becomes the allowable value or less, the shutter 18 is opened and the beam splitter 12 is removed from the optical path, whereby control is provided so as to start the exposure.

Inventors

• 👤 Ikuo Hikima
• 👤 郁雄 引間
• 👤 Akira Miyaji
• 👤 章 宮地

Bibliographic Details