| 摘要 |
<p>A square-shaped electron beam is stepped from one predetermined position to another in a line-by-line scan to form a desired pattern on each chip of a semiconductor wafer to which the beam is applied. At each of the predetermined positions, the beam is on, off, or on for a portion of the time period at which the beam is disposed at the predetermined position. The beam also can be offset both along its direction of movement and perpendicular thereto at each of the predetermined positions. Control of this movement of the beam is obtained through utilizing a memory with no change being made in the memory if the predetermined position at the next line does not have any change from the predetermined position at the line along which the beam is moving.</p> |
