Abstract: A method for evaluating the measure precision of patterns such as photoresist and etched ones, and a photomask therefor. The photomask according to the present invention has a mask pattern corresponding to a pattern desired to be formed in a substrate, and also has a measure precision evaluating pattern formed at an area different from where the mask pattern is present. The measure precision evaluating pattern comprises a first measure precision evaluating pattern which has a plurality of pairs of pattern elements opposite to each other with a predetermined distance interposed therebetween, and a second measure precision evaluating pattern which has a plurality of pairs of pattern elements overlapped each other in a predetermined measure and arranged opposite to each other to form a constricted portion. The distance or the measure of overlapped area between paired pattern elements is varied with every pair of pattern elements.

Abstract: A photomask is disclosed which is suitable for use in the one-mask method capable of forming a plurality of patterns with one exposure, and in which an opaque pattern having a predetermined form and a semi-transparent pattern having another predetermined form are formed on a transparent substrate, and the semi-transparent pattern is formed of an opaque film having a large number of fine through holes.

Abstract: In the projection-copying of a mask on a workpiece including a light-reflecting semiconductor substrate, the alignment of mask and workpiece is effected by illuminating marks on the substrate which appear dark relative to a surrounding area. To provide each mark with a contrasting background of sufficient brightness, a partly reflecting surface layer overlying the substrate in that area has a nonuniform optical thickness whereby cancellation of reflections due to interference is limited to isolated regions.

Abstract: A photomask comprises a transparent substrate on one surface of which a mask pattern is formed of a photoshielding film and the opposite surface of which is roughened in order that rays of incident light are refracted diffusedly through the rough surface and the images of minute particles of dust disappear in the projected pattern.

Abstract: A projection mask and method and apparatus for production thereof comprising a substrate carrying a mask thereon, a cover glass covering the pattern mask and sealed at peripheral edges thereof to the substrate defining a space between the substrate with the mask and the cover glass. A particle-free fluid is provided in this space. A projection printing system projects illumination through such a projection mask into a light sensitive substrate.

Abstract: An apparatus and method is disclosed which will rapidly provide uniform layers of two liquid photopolymerizable materials for a capped (i.e., two layer) printing plate. The apparatus comprises a dual manifold which spans the plate-forming area of a surface and which is moved in tandem transversely in order to provide two overlapping layers of liquid photopolymerizable materials.

Abstract: A computer-generated halftone contact screen is disclosed which consists of a rectangular array of small abutting square areas each of uniform transmittance (density), in which the transmittance (density) of the squares is described by a random variable whose distribution is controlled to give the screen a desired reproduction curve. The facsimile produced using the screen, its equivalent produced by computer-assisted means, and its representation in computer memory are disclosed.

Abstract: A method of making a halftone contact screen having a plurality of discrete different optical transmittance levels by making multiple relative translations of light-sensitive material under and in close contact with a ruling mask while exposures to light through the ruling mask are made between the translations. The mask comprises a thin flat plate having an array of parallel periodic equal width opaque straight bars separated by an array of parallel equal width transparent bars. In a first process, translations are normally made perpendicular to the parallel of the bars. Two-dimensional or dot halftone contact screens are made by repeating the process wherein the light-sensitive material is rotated relative to the ruling mask, in its own plane, at an angle greater than zero to the direction of the ruling bars during the first process. Using the single process creates a line halftone contact screen; adding the second process creates a dot halftone contact screen.

Abstract: A process for fabricating polyimide membrane x-ray lithography masks is described. Thin membrane of polyimide is formed by spinning polyamic acid on a glass substrate and polymerizing in situ. The glass substrate acts as a holder and efficient heat sink during formation of gold absorber patterns on top of the polyimide. A support ring is then bonded to the polyimide, and the glass etched in dilute HF. Optically smooth polyimide membranes with thickness from 0.5 to 5 .mu.m are readily achieved. The method and resulting product is not limited to the above materials or to masks.

Abstract: There is described a unique mask and method of making same. The mask is especially useful in high resolution fabrication techniques such as in making magnetic bubble domain structures, semiconductor device structures and the like. The mask includes a suitable support of appropriate density to be substantially transparent to various types of radiation such as, but not limited to, E-beams, X-rays and the like. A layer of material which is substantially opaque to the same radiation and which can have the solubility thereof changed by application of E-beams or the like is provided on the support material. The mask is exposed to the solubility changing radiation wherein a pattern is defined in the layer, the layer is etched in a non-critical etch so that the soluble portion thereof is removed and the remaining material provides a suitable pattern. To the extent necessary, a suitable auxiliary support member can be provided to the support.

Abstract: An improved halftone dot screen for use in reproduction of continuous-tone graphic images is disclosed. The screen comprises a two-dimensional matrix of cells (dots) each cell having a common pattern of transmittance to radiation utilized in the reproduction process. The common pattern of transmittance for each cell is characterized by a finite number of different discrete transmittance level patterns. In a preferred embodiment, these patterns include portions arranged along the respective sides of a parallelogram. In one preferred embodiment, the discrete transmittance level patterns comprise an array of concentric parallelograms. Each parallelogram has a plurality of dot portions arranged along the sides of the parallelogram. The sides of the parallelogram patterns are preferably disposed at a substantial angle to the horizontal to reduce moire and rosette pattern effects and to simplify the reproduction process.

Abstract: There is described an exposure frame for aligning and holding photomasks in registration with a printed circuit board coated with a light sensitive material. The printed circuit board is held between an independently adjustable mounting strip and slides. A contact strip is floated on the mounting strip by a spring mounting to permit the slides to position the printed circuit board relative to the photomask. The photomask, in turn, is mounted on the adjustable mounting strip. This facilitates good registration between the board and mask.

Abstract: A photograph of an object is made on color film in a conventional manner. Then the object is back-lighted only to silhouette it and a second photograph is made using the same film. The two films are developed simultaneously so as to subject them to identical processing conditions. Using the photograph taken while the object was back-lighted, a contact exposure is made on a high contrast film to produce a negative. After development of this negative, it and the initial, front-lighted, photograph of the object are employed on a scanner to produce the color separations for printing purposes.

Abstract: The claimed reproduction procedure avoids the use of as many masks as there are degrees of shading for each primary color.For each primary color, only a single mask capable of being stripped and not painted in gouache is used. This mask serves as the mask assignable to the most densely shaded areas, and then upon stripping, as each of the masks assignable to the less densely shaded areas and so on to the weakest density. The mask acts as a photomask for a film which is underexposed for each degree of shading desired bymeans of a single screen.The invention is applicable to the reproduction of all documents using a number of shades of color.

Abstract: An apparatus for use in producing an illumination pattern on an electrically conductive mask blank having a photoresist coating thereon for a color cathode ray tube. The apparatus comprises a rigid, transparent substrate which has a first preselected pattern on the substrate, having a preselected optical density. The first pattern has first areas corresponding in distribution to the pattern of apertures to be formed in a mask blank, at least a predetermined group of the first areas being smaller in size than the desired ultimate mask aperture size. The substrate has a second preselected pattern having second areas surrounding the first areas, at least a predetermined group of the second areas corresponding to the first group of areas and having the size and outer configuration of the desired ultimate mask apertures. A third area between the second areas of the second preselected pattern has an optical density substantially different from the optical density of the first areas of the first preselected pattern.

Abstract: In a projection printing system the pattern mask, whose image is projected onto a light sensitive layer, is encased in a glass sandwich so that any dirt particles on the surfaces of the sandwich are out of focus and are not printed in the light sensitive layer.

Abstract: Disclosed is a photomask and a method for the manufacture thereof. A metal stencil is disposed on a glass substrate such that only preselected areas of the glass which are to be made opaque are exposed. A grit-etch step follows in which depressions are formed in the glass substrate in the preselected areas. Fusible masking material is sprayed in the depressions through the metal stencil. The masking material is preferably in particulate form in a volatile carrier liquid. The carrier liquid is preferably first driven off and, then, the combination is exposed to a relatively high temperature that fuses the masking material to the substrate.

Abstract: Light quantization of elemental areas of pictorial information by a plurality of contiguous light integrating tunnels, either with or without one of a group of different sampling-function array masks and/or printing-function array masks, is used to modify the original picture information for such purposes as subjectively providing a (1) more pleasing picture, (2) striking special display effects and (3) studying visual perception by the human visual system. Analog processor replaces expensive computer equipment which also required tedious programming, formerly required for producing similar modification of picture information.

Abstract: A roller is coupled to a movable support frame which in a first position bears a flexible halftone screen which is fully wound up about said roller. As the support frame is translated in a first direction across the film mounted upon a vacuum platen, the flexible screen unwinds and is laid flat across the platen. When the movable support frame is translated in a second direction, the screen is thereafter wound up about said roller somewhat in the manner of a "reverse windowshade.

Abstract: A sheet of opaque material has a window therein and marks on the sheet indicating the positioning of an edge of a test print for placement over the window to expose different areas of the test print in succession.

Abstract: Disclosed is an improved microform card which includes a wear-strip spacer element structure located on the card surface in one of several configurations, some containing coded secondary information. The wear-strip spacer elements separate the card surface from adjacent optical elements in a card utilizing apparatus by a distance sufficient to prevent the formation of colored Newton rings at the card-to-optical-element interface. Card utilization equipment capable of recognizing the presence of wear-strip spacer elements on a microform card and using any secondary information encoded thereon is also disclosed.

Abstract: A method for producing a photomask by exposing and development-processing a photographic light-sensitive material including a transparent support having thereon a masking layer and a silver halide emulsion layer to thereby form silver image areas, etch-bleaching the silver halide emulsion layer to thereby remove the silver image areas to uncover the masking layer thereunder, subjecting the coated support to etching to etch the uncovered masking layer with a mixed solution containing hydrofluoric acid and ammonium fluoride to thereby uncover the transparent support thereunder, and then removing the non-silver image areas to thereby reveal the masking layer.

Abstract: A method for producing a photomask, by exposing and development-processing a photographic material including a transparent support having thereon a masking layer and a silver halide emulsion layer to thereby form a silver image, etch-bleaching the silver halide emulsion layer to thereby remove the silver image areas, baking the remaining non-silver image areas to thereby decompose the binder contained therein, subjecting the coated support to etching to thereby remove the masking layer located at the areas corresponding to the silver image, and removing the decomposed binder to thereby uncover the masking layer at the areas corresponding to the non-silver image areas.

Abstract: A colored photomask has a glass substrate with a masking film deposited thereon formed of a non-stoichiometric chromium oxide composition produced by heating chromic oxide or metallic chromium in a clear oxidizing atmosphere of oxygen or an oxygen-nitrogen mixture at a total pressure of 0.5 .times. 10.sup.-.sup.4 to 5 .times. 10.sup.-.sup.4 Torr and at an oxygen pressure of 0.1 .times. 10.sup.-.sup.4 to 5 .times. 10.sup.-.sup.4 Torr to generate the vapor from the chromic oxide or metallic chromium, and depositing the rising vapor onto one surface of the glass substrate heated and positioned within the oxidizing atmosphere in a manner similar to a known vacuum-plating process, and at least one window in the masking film formed by etching the film.