| 摘要 |
PURPOSE:To correct the deflection direction of electron beam with a good following property by detecting the change of the movement velocity of a table in real time. CONSTITUTION:After moving in the +y direction by L, table 9 moves in the x direction by l in steps; and after moving in the -y direction by L, table 9 moves by l in steps to perform a beam exposure. The brightness dependent upon the movement of the table is converted photoelectrically by laser reflector 11 and laser interference meter 12 and is counted in 13 and is operated in 14 to calculate the movement velocity of the table and the velocity change. Correcting components DELTAy and DELTA<2>y are obtained from these values to control deflection through interface 15 by controller 16. Controller 16 applies a prescribed voltage to deflecting plates 6 and 7 synchronously with the movement of the table. Thus, a very accurate beam scanning without pattern slippage DELTAy and change components DELTA<2>y of it is performed. |
