Exposure control in X-ray exposure apparatus.

摘要

Exposure control method and apparatus particularly suitably usable in an X-ray exposure apparatus, for exposing a mask and a wafer to a radiation (X-rays) from a synchrotron to transfer a pattern formed on a mask onto the wafer, is disclosed. Shutter device for controlling passage and interception of the synchrotron radiation is provided between the synchrotron and the wafer. The shutter device includes a blade member having a leading edge and a trailing edge which are rectilinearly movable in a direction in which there exists non-uniformness in illuminance of the radiation. The leading edge is used to determine the timing of start of passage of the radiation to the wafer, while the trailing edge is used to determine the timing of interception of the radiation. The moving speeds of the leading edge and the trailing edge are controlled independently of each other to provide different exposure times for different portions of an exposure region on the wafer, in accordance with the non-uniformness in illuminance. By this, the amount of absorption of radiation by a resist material on the wafer can be uniformized throughout the exposure region.