| 摘要 |
PURPOSE:To detect the position where an error of irradiation is generated without delay by a method wherein whether there is reflected electron detecting signal is detected in the condition wherein a blanking signal passes through an electron beam, and when there is no detected signal, a decision is given as the error of irradiation, with the result that a positional information is written in a memory storage. CONSTITUTION:A reflected electron detection signal PA can be obtained from a reflected electron detecting device 108 by interrupting an electron beam 104 with a blanking signal BL. Said signal PA is inputted to a reflected electron detecting signal generator 206, differentiated by a differentiation circuit 206A, amplified 206B, and compared with the comparison voltage CV of a DA converter 206D. The waveform of the output pulse PC is shaped up (206E), the output PD of the circuit 206 is given to an abnormality detecting circuit 207, and an abnormality extraction clock PE is received from a patterning control system 201. Then, the circuit 207 detects the state of nil of the signal PD when clock PE is present, and the signal PE is outputted as an abnormality detecting signal PF. This signal PF is written in a memory circuit 208, which stores the positional information of deflection and the information of stage position at that time to indicate the generation and the position of the irradiation error.
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