Exposure apparatus
US4713675A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 29, 1986 |
| Grant date | Dec 15, 1987 |
| Priority date | — |
| Expiry date | Oct 29, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70558
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An exposure apparatus for exposing a semiconductor wafer to a pattern of the mask with light from a light source, thereby to transfer the pattern of the mask onto the wafer. The appartus includes a shutter operable for selectively passing/blocking the light from the light source to the wafer, and a control system for controlling the intensity of light emission from the light source in a manner that the intensity becomes greater at the time of exposure operation than that at the time of non-exposure operation. The shutter opening movement for effecting the exposure is initiated after the intensity of light from the light source, when it is increased by the control system, becomes substantially stable. This avoids unpreferable effects, upon exposure, of overshooting, ringing, etc. in the light from the light source, such that the amount of exposure of the wafer can be controlled accurately.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.