| 摘要 |
PURPOSE:To make it possible to detect errors in a pattern due to erroneous operation and the like, by providing a circuit memorizing the number of shots required for pattern scribing, a blanking counter, and a beam detection counter, and comparing the contents of the circuits one another at the appropriate time. CONSTITUTION:The ON and OFF operation and the deflection of the electron beam are controlled by a digital control circuit 11 based on the pattern data and the control signal from a CPU10. For example, in a formed beam system, the number of divisions of the pattern is computed and sent to a shot number memory circuit 12. Pulses are sent to the blanking counter 14 every time the blanking signal is generated from a driving circuit 16. The pulses are sent to the beam detection counter 15 through a detector 25 and a circuit 17 every time the detected signal of the beam which has arrived at a exposing specimen 26, exceeds a specified level, and the pulses are counted. The contents of the circuits 12, 14, and 15 are inputted in a comparator 13 which is provided in the circuit 11, every time the scribing of the arbitrary unit of the pattern data has completed. The erroneous operation or abnormality in the circuit systems and the electrooptical systems can be detected based on the agreement or disagreement in the comparison, and the pattern error can be confirmed. |
