摘要 |
An improved method for coating a semiconductor wafer with a uniform layer of photoresist or other liquid film is provided. The liquid is first semi-uniformly deposited on the wafer by spraying or otherwise. Thereafter, the wafer is rotated about an axis perpendicular to the plane of the wafer and removed from the wafer. In the preferred embodiment, a number of wafers are placed about the perimeter of a large, flat disc which is rotated about its center. The liquid is spread over the surface of each wafer by the centrifugal force generated by such rotation. By placing the wafers at a distance from the axis of rotation, the centrifugal force on all points of each wafer is approximately the same, thereby providing for a uniform spreading of the film over the wafer.
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