摘要 |
<p>A method for projecting a predetermined pattern of an electron beam from an emitter to a wafer in a vacuum chamber of an electron-beam lithography system is provided. An initial condition for performing an electromagnetic focusing is first set and outspread phenomenon of the electron beam, which is caused by an initial emitting velocity difference and an initial emitting angle difference between electrons emitted from the emitter, is corrected. Then, a shift of the electron beam, which is caused when an electric field is not in parallel with a magnetic field, is corrected and a shift of the electron beam, which is caused by a gradient of the magnetic field, is corrected, after which an increase of a beam diameter of the electron beam, which is caused by Coulomb-interaction between the electrons emitted from the emitter, is corrected. Then, it is determined if a focusing error is within a range of an allowable error. When it is determined the focusing error is out of the range of the allowable error, the above operations are repeated.</p> |