| 摘要 |
PURPOSE:To shorten the working time of exposure for the vector scanning by deciding queuing time in accordance with the flying distance of the electron beam. CONSTITUTION:The information of the X-direction end point of pattern A and the X-direction start point of pattern B are memorized in register 1 and 2 each in the stage under which the exposure is shifted from pattern A to B. In the same way, both the end and start points of both patterns in the Y-direction are memorized in register 3 and 4 respectively. Based on these memorization, the X- and Y-direction flying distances of the electron beam are calculated 5 and 6 to be supplied to register 7 with memorization of the larger distance. Then the queuing time signals are generated 8 according to the output value of register 7 to shield the electron beam. Thus the start of exposure is reduced. During this time, the D/A converter, the amplifier for driving polarizer and others are adjusted completely. The adjustment is finished properly for the polarization system reating the small flying distance, and then the beam shielding is opened to carry out exposure. Accordingly, the exposure working time can be accelerated greatly compared with the conventional method in which the maximum queuing time is applied irrespective of the beam flying distance. |
