| 摘要 |
PURPOSE:To permit a practical high-speed image drawing, by effecting the same with a high-accelerating voltage, a low dosage and a small deflection in the case of a small-sized image drawing; and with a low-accelerating voltage, a low dosage and a large deflection in the case of a large-sized image drawing. CONSTITUTION:The minimum picture element (d) (equal to the beam diameter) corresponding to the minimum pattern dimension (x) in an LSI pattern is fed through a console unit 636. An optimum accelerating voltage V and dosage D for the formation of the minimum pattern dimension (x) are selected and fed through the console unit 636. A deflection oscillation width l is determined from (d) and V upon condition that they satisfy a certain expression of relation. The width l may be processed in a computer 630 or fed through the console unit 636. In this stage, the accelerating voltage and beam diameter in the electrooptic system are set according to commands from the computer 630. Variations of the accelerating voltage and the beam diameter change the deflection oscillation width and the deflection direction; therefore, these value and direction are detected by means of a mark 616 and fed back to a deflection controller 627. |
