| 摘要 |
PURPOSE:To magnify the depth of focus at the time of projection exposure of a contact hole pattern. CONSTITUTION:On the pupil surface there is provided a polarizing plate, a 1/2 wavelength plate, a 1/4 wavelength plate, or an optically active material which makes the polarization state of an imagery light flux LFa different from the polarization state of an imagery light flux LFb. The flux LFa passes the central circular region of the pupil surface of a projection optical system PL. The flux LFb passes the ring belt type region around the central circular region. Thereby the SFINCS method of turning the two imagery light fluxes (LFa, LFb) into at least an incoherent state is applied. |
