摘要 |
An exposure method is disclosed. A wafer coated with a photoresist layer having an exposure threshold dose is provided. The wafer has at least a central region and a peripheral region. Then, a compensating light beam having a first dose directs on the photoresist layer within the peripheral region. Next, a patterned light beam having a second dose is then projected, in a step-and-scan manner, onto the photoresist layer, thereby exposing the photoresist layer. The total dose of the first energy and the second energy is above than the exposure threshold dose.
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