Abstract: Techniques are disclosed to compensate for distortions in lithography by locally heating the membrane in a lithographic mask. The techniques may be used both to shrink and to expand areas of the mask locally, in order to adjust for varying magnitudes and signs of distortion. In one embodiment the correction method comprises two steps: (1) A send-ahead wafer is exposed and measured by conventional means to determine the overlay errors at several points throughout the field. (2) During exposure of subsequent wafers, calibrated beams of light are focused on the mask. The heating from the absorbed light produces displacements that compensate for the overlay errors measured with the send-ahead wafer. Any source of distortion may be corrected—for example, distortion appearing on the mask initially, distortion that only develops on the mask over time, or distortion on the wafer.

Abstract: The present invention provides a method of manufacturing a circuit element which includes a step of performing first exposure for transferring a pattern having a narrowed portion for forming a particular pattern, onto an exposure-target substrate, and a step of moving the pattern in a direction not parallel to a segment forming an outer circumference of the narrowed portion and performing second exposure for transferring the pattern onto the exposure-target substrate.

Abstract: An optical element includes two electrodes 1 and 2 arranged at a distance to oppose each other and configured to converge an electron beam. The opposing surfaces of the electrodes 1 and 2 are so formed as to be cylindrically symmetrical along the beam passing direction and to form curves obtained by deforming hyperbolas in a direction perpendicular to the beam passing direction, in order that an electric field whose effective part except for an arbitrary constant of the field potential is given by.phi.=(k/2)r.sup.2 -.alpha.lnr-kz.sup.2is spatially partially formed in a cylindrical coordinate system defined by (r, z, .theta.).

Abstract: A mask inspection apparatus of the present invention includes an electron gun for irradiating an electron beam onto a mask with a pattern formed thereon, an electron lens for magnifying an electro-optic mask image passed through the mask, a fluorescent screen for converting the magnified electro-optic mask image to an optical mask image, an optical lens for optically magnifying the optical mask image, a detector for detecting the magnified optical mask image, and a comparator for inspection a defect in the pattern on the basis of the image. By doing so, it is possible to suppress aberrations resulting from the electro-optic magnification and, in addition, inspect the pattern with a high resolution through optical magnification. It is also possible to inspect the mask at its area and to inspect a defect at high speeds.

Abstract: A method for forming an X-ray exposure mask having an X-ray permeable film with a high visible-light transmissivity. The method includes the steps of forming an aluminum oxide anti-reflective film on an x-ray permeable film, placing an x-ray absorber on the anti-reflective film and etching with the x-ray absorber to form x-ray pattern.

Abstract: An X-ray mask includes an X-ray transmitting thin film consisting of SiC, a W X-ray absorber formed on one surface of the thin film and having a predetermined pattern, and a support frame arranged on a peripheral portion of the thin film. The thin film is constituted by a plurality of SiC layers having different C/Si composition ratios. When the thin film is formed by a CVD method, the flow rate of a gas containing Si is fixed while a gas containing C or a diluted gas mixture of the gas containing C is changed. Consequently, the visible light transmittance of the thin film is improved.