X-ray Exposure Process Patents (Class 430/967)
  • Patent number: 4465768
    Abstract: A radiation-sensitive composition comprising an iodine-containing azide compound at least a part of which can be fixed substantially in a polymer by exposure to a radiation and a polymer, or a radiation-sensitive composition comprising an azide compound, an iodine compound at least a part of which can be fixed substantially in a polymer by exposure to a radiation and a polymer. This composition can be subjected to the dry development with oxygen plasma after the exposure followed by heating.
    Type: Grant
    Filed: July 13, 1982
    Date of Patent: August 14, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Takumi Ueno, Hiroshi Shiraishi, Takao Iwayanagi, Takahiro Kohashi, Saburo Nonogaki
  • Patent number: 4454209
    Abstract: A lithographic process utilizing soft x-rays or ions to achieve high resolution is disclosed. The process is particularly useful and semiconductor processing where high resolution is required to achieve a high density. The process utilizes a mask to selectively expose a photoresist to soft x-rays of flood beams of ions. The mask comprises a thin metallic foil supported by a frame such that the foil is in tension. The frame includes optical alignment keys. A second patterned layer of metal is affixed to the foil to form areas which are non-transparent to the soft x-rays or flood ion beams for delineating the elements of a semiconductor circuit, for example. This permits the mask to be optically aligned using conventionally techniques with high resolution being achieved due to the short wavelength of the x-ray radiation or the ion beams.
    Type: Grant
    Filed: January 19, 1983
    Date of Patent: June 12, 1984
    Assignee: Westinghouse Electric Corp.
    Inventor: Phillip D. Blais
  • Patent number: 4453262
    Abstract: In order to obtain shorter exposure time and to obtain a longer life in x-ray lithography apparatus, an x-ray target made of tungsten is utilized and the apparatus operated to generate the tungsten M-line, this line being at a wavelength which will be absorbed by the resist normally used in lithography. To develop the resist, which was initially designed for use in an electron beam lithography, a developing method is used in which an initial short development with a high concentration is first carried out followed by a longer, full development with a concentration which is approximately the lowest at which complete development will take place.
    Type: Grant
    Filed: May 24, 1982
    Date of Patent: June 5, 1984
    Assignee: The Perkin-Elmer Corporation
    Inventor: William D. Buckley
  • Patent number: 4451544
    Abstract: The invention provides a mask structure for X-ray lithography, having a mask substrate of an X-ray transmitting material, a mask pattern of an X-ray absorbing material which is formed on the surface of the mask substrate or therein, a support ring for supporting the rear periphery of the mask substrate, and a lattice-shaped metal film embedded in a lattice-shaped slit in the mask substrate. The mask structure with a large area has a dimensional stability.
    Type: Grant
    Filed: June 17, 1982
    Date of Patent: May 29, 1984
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventor: Katsuhiro Kawabuchi
  • Patent number: 4436797
    Abstract: An improved X-ray lithography mask has been fabricated by forming an X-ray absorbing lithography pattern on a supporting foil of hydrogenated amorphous carbon. The substrate foil is formed by depositing a carbon film in the presence of hydrogen onto a surface having a temperature below 375.degree. C. The hydrogen concentration is maintained sufficiently high that the resulting film has at least one atom percent of hydrogen. A film having about 20 atom percent of hydrogen is preferred. While impurities are permitted, impurities must be maintained at a level such that the optical bandgap of the resulting film is at least one electron volt. A film with an optical bandgap of about 2 electron volts is preferred.
    Type: Grant
    Filed: June 30, 1982
    Date of Patent: March 13, 1984
    Assignee: International Business Machines Corporation
    Inventors: Michael J. Brady, Bernard S. Meyerson, John M. Warlaumont
  • Patent number: 4430419
    Abstract: The invention provides a positive resist comprising a copolymer of 60 to 90 mol % of phenylmethacrylate and 40 to 10 mol % of methacrylic acid.The invention also provides a method for forming a pattern of a positive resist comprising the steps of:forming on a substrate a film of a positive resist which comprises a copolymer of 60 to 90% of phenylmethacrylate and 40 to 10 mol % of methacrylic acid;pre-baking said positive resist film to cross-link said copolymer;selectively radiating said positive resist film which has been pre-baked with a high energy beam to form a latent image; anddeveloping said latent image with a developing solvent. Said positive resist has excellent resistance to dry etching and high sensitivity, and shows good adhesion to a substrate and can realize high resolution.
    Type: Grant
    Filed: January 15, 1982
    Date of Patent: February 7, 1984
    Assignee: Nippon Telegraph & Telephone Public Corporation
    Inventor: Katsuhiro Harada
  • Patent number: 4426439
    Abstract: A negative photoresist emulsion, wherein after a film of negative photoresist emulsion on a substrate has been exposed for pattern writing in vacuum to charged particle beams or soft X-ray beams, the film-coated substrate is transferred to, and kept in, a chamber filled with non-oxidizing gas, and then the substrate is removed to the outside atmosphere. By this method, a curing effect of the photoresist film is prevented, enabling formation of fine patterns with precision. An apparatus for carrying out the above method, has a gas chamber filled with non-oxidizing gas connected to an exposure chamber, and the substrate, after such exposure, is kept in an atmosphere of non-oxidizing gas in the gas chamber before being removed to the outside atmosphere. In either the above-method or apparatus, the concentration of oxygen in the non-oxidizing gas must be less than 5%, preferably less than 1%.
    Type: Grant
    Filed: December 11, 1981
    Date of Patent: January 17, 1984
    Assignee: Fujitsu Limited
    Inventors: Koichi Kobayashi, Kenichi Kawashima, Shuzo Oshio
  • Patent number: 4425423
    Abstract: An Auger microlithography process wherein a beam of substantially monochromatic X-rays is passed through a photomask to induce Auger electrons from a selected atomic element within a photosensitive layer which Auger electrons act on a material in that layer to cause a physicochemical change thereof and form a latent image. The X-rays used are selected to be substantially monochromatic such that the range of wave lengths falls largely or almost totally within the Auger window, as defined, determined by the particular electron shell of the atomic element to be activated to produce the Auger electrons.
    Type: Grant
    Filed: September 17, 1982
    Date of Patent: January 10, 1984
    Inventor: Chia-Gee Wang
  • Patent number: 4421844
    Abstract: Disclosed is a process for the preparation of relief copies, comprising the steps of imagewise irradiating a radiation-sensitive copying material comprising a layer support and a radiation-sensitive layer comprising (a) a compound which upon irradiation splits off acid, and (b) a compound possessing at least one acid-cleavable C--O--C group; heating the imagewise irradiated copying material to a temperature above room temperature for a period of time sufficient to produce an increase in radiation sensitivity of the radiation-sensitive layer; and washing out the irradiated layer areas by means of a developer.
    Type: Grant
    Filed: October 9, 1981
    Date of Patent: December 20, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gerhard Buhr, Marie-Luise Geus
  • Patent number: 4401738
    Abstract: An X-ray mask including a pattern of X-ray absorbing material on a thin membrane is provided. The mask includes overlapping first and second patterns of X-ray absorbing material. This permits X-ray lithography printing of lines in complex patterns required for large scale integration. The X-ray mask can provide patterns of less than 20 A in thickness by X-ray irradiation.
    Type: Grant
    Filed: November 16, 1981
    Date of Patent: August 30, 1983
    Assignee: Kabushiki Kaisha Suwa Seikosha
    Inventor: Seiichi Iwamatsu
  • Patent number: 4396704
    Abstract: Solid state devices are produced by dry etching of a resist film to produce a negative resist pattern. The film comprises a polymer typically containing a halogen, and at least one type of silicon-containing or nonsilicon-containing organometallic monomer. The radiation, typically X-ray radiation, locks the monomer or monomers into the polymer, with a subsequent fixing step removing the unlocked monomer or monomers in the unirradiated portion of the resist. The film is then exposed to a plasma comprising oxygen, which removes the unirradiated portion at a faster rate than the radiated portion, producing a negative resist pattern. The plasma development is typically accomplished by reactive ion etching. Sensitizers can be used to extend the wavelength response of the films, typically into the ultraviolet or visible regions.
    Type: Grant
    Filed: April 22, 1981
    Date of Patent: August 2, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Gary N. Taylor
  • Patent number: 4394439
    Abstract: Permanent records of X rays or radiations of shorter wavelengths are formed on a film substrate by direct exposure to the radiation and heat development. The process is not sensitive to visible radiation and can therefore be carried on in daylight. An X ray photosensitive film containing a halogenated photodegradable polymer and an aryl dye promoter reacting to free radicals is exposed to an X ray image and then heated under conditions which allow the free radical generated by the photodegradation of the polymer to migrate and react with the aryl dye promoter to provide the imaging dye. The X ray photosensitive layer of the X ray photosensitive film or paper includes, in addition to the photodegradable polymer and the aryl dye promoter, a heat activable complexing agent and an organic binder. The process can be carried out using currently available X ray equipment with the advantage of handling the film in daylight and eliminating chemical development.
    Type: Grant
    Filed: May 28, 1981
    Date of Patent: July 19, 1983
    Inventor: Jean J. Robillard
  • Patent number: 4394770
    Abstract: An X-ray package for X-raying an object such as a portion of a human body includes a film which has been pre-exposed to dimensional indicia so that, after the package has been exposed to X-radiation relative to the object and the film has been developed, the image on the film includes both the object and the dimensional indicia. The package is made by unwinding a roll of pre-exposed film while simultaneously unwinding rolls of cover materials to form a composite strip of film and cover materials and forming X-ray packages successively from the end of the composite strip. The film is pre-exposed by unwinding a roll of unexposed film while simultaneously unwinding a control strip and the control strip causes the film to advance in steps of precisely equal lengths. Between each advance of the strips, a portion of the strip of film is exposed to dimensional indicia.
    Type: Grant
    Filed: June 29, 1981
    Date of Patent: July 19, 1983
    Inventor: Peter J. La Franca
  • Patent number: 4393127
    Abstract: A structure for shaping or masking energetic radiation is described. The structure comprises a shallow silicon body having at least one through opening, and a metal silicide layer covering the surface of the structure. The structure characterized by having a high mechanical, and thermal stability may be used particularly in electron and X-ray lithography. More specifically, the structure may be used as an aperture for electron beams, or as a mask for X-rays. The production of the structure includes the steps of making through openings in the silicon body, and the forming of the silicide layer by vapor depositing a metal on the surface of the silicon body and by subsequent annealing.
    Type: Grant
    Filed: July 17, 1981
    Date of Patent: July 12, 1983
    Assignee: International Business Machines Corporation
    Inventors: Johann Greschner, Georg Kraus, Gerhard E. Schmid
  • Patent number: 4388728
    Abstract: A soft X-ray lithography system including an X-ray tube having an evacuated and sealed-off envelope provided with an X-ray transparent window made of beryllium material and enclosing a rotatable anode target made of graphite material, the target having an annular sloped surface carrying a focal track layer made of titanium carbide material and having a focal spot area aligned with an electron emitting cathode to generate characteristic titanium K alpha X-rays which pass in a beam through the window, a mask aligned with the window and having transparent portions which transmit the beamed X-rays, and a workpiece, such as a semiconductor wafer, for example, having a surface coated with a photoresist film disposed in alignment with the mask to have selected portions of the film irradiated by the X-rays transmitted through the transparent portions of the mask.
    Type: Grant
    Filed: November 20, 1978
    Date of Patent: June 14, 1983
    Assignee: The Machlett Laboratories, Incorporated
    Inventor: Saurabh D. Emmanuel
  • Patent number: 4377627
    Abstract: A semiconductor substrate is mounted in an electron beam image projector with a mask. The patterned electron beam from the mask comprises a first sub-pattern and a second lower intensity sub-pattern. The difference in the intensities of the two sub-patterns permits the automatic alignment of the patterned electron beam relative to the substrate by detecting when the first sub-pattern is incident on a reference marker pattern on the substrate, while the first and second sub-patterns together expose an electron sensitive layer at the entire area of the reference marker pattern. The part of the layer retained after developing can be used as an etchant mask during the definition of a protective layer or the removal of unwanted material from the entire area of the reference marker pattern depending on whether the layer is a negative or a positive electron sensitive material.
    Type: Grant
    Filed: December 15, 1980
    Date of Patent: March 22, 1983
    Assignee: U.S. Philips Corporation
    Inventor: David J. Vinton
  • Patent number: 4350755
    Abstract: Relatively monochromatic soft X-rays at 4.5 m.mu. is used to induce auger electrons from the silver-halide crystal to sensitize the photosensitive grain, and the exposed crystal is developed into a fine silver grain. The pattern of the silver grains with sizes of about 0.02.mu. can be used as a photoresist with a resolution of about 0.1.mu.. The silver grains can also be used to initiate certain organic compounds for the resist, also with a resolution of the order of 0.1.mu..
    Type: Grant
    Filed: July 23, 1980
    Date of Patent: September 21, 1982
    Inventor: Chia-Gee Wang
  • Patent number: 4349621
    Abstract: A process for X-ray microlithography useful in the manufacture of microelectronic devices is provided. In the process, a mask in the form of a thin film of a eutectic is interposed between a source of X-rays and a substrate to selectively expose a layer of X-ray sensitive resist situate on the surface of the substrate. After exposure, the resist is developed to yield in the resist a replica of the submicron minimum feature size pattern of the mask.
    Type: Grant
    Filed: April 13, 1981
    Date of Patent: September 14, 1982
    Assignee: General Electric Company
    Inventor: Harvey E. Cline
  • Patent number: 4342917
    Abstract: In order to obtain shorter exposure time and to obtain a longer life in x-ray lithography apparatus, an x-ray target made of tungsten is utilized and the apparatus operated to generate the tungsten M-line, this line being at a wavelength which will be absorbed by the resist normally used in lithography. To develop the resist, which was initially designed for use in an electron beam lithography, a developing method is used in which a initial short development with a high concentration is first carried out followed by a longer, full development with a concentration which is approximately the lowest at which complete development will take place.
    Type: Grant
    Filed: November 9, 1979
    Date of Patent: August 3, 1982
    Assignee: The Perkin-Elmer Corporation
    Inventor: William D. Buckley
  • Patent number: 4329410
    Abstract: A method of depositing X-ray absorber patterns on a mask membrane to achieve minimum pattern feature dimensions less than 1 .mu.m. The membrane is covered with an ultraviolet (VU) sensitive photoresist which carries a thin metallic film. The metallic film is coated with an electron beam resist. The electron beam resist is exposed to the desired pattern by an electron beam. After development, the metal film is etched through the remaining electron beam resist. This forms a stencil overlying the lower UV photoresist layer which is then exposed by an ultraviolet or soft X-ray source. After development, an X-ray absorber, such as gold, is deposited on the membrane. The final exposure step may be done by means of a point source of radiation. The X-ray absorbers will then have sloping walls to prevent shadowing of the X-ray source.
    Type: Grant
    Filed: December 26, 1979
    Date of Patent: May 11, 1982
    Assignee: The Perkin-Elmer Corporation
    Inventor: W. Derek Buckley
  • Patent number: 4328202
    Abstract: Ionic compounds of the formula ##STR1## wherein X is --CONR.sub.1 R.sub.2, --CH.sub.2 NH.multidot.Acyl or --CH.sub.2 OH; Y is --NR.sub.3 R.sub.4, --NH.multidot.Acyl or OR.sub.5 ; R.sub.1, R.sub.2, R.sub.3 and R.sub.4 can be identical or different, and each is hydrogen, C.sub.1-6 - alkyl or C.sub.2-8 -alkyl substituted by 1-5 OH groups and/or by one C.sub.1-3 -alkoxy group, R.sub.5 is C.sub.1-6 alkyl or C.sub.2-8 -alkyl substituted by 1-5 OH groups and/or by one C.sub.1-3 -alkoxy group, and Acyl, which can be the same or different in X and Y, is C.sub.2-6 -alkanoyl or C.sub.2-6 -alkanoyl substituted by 1-4 OH groups and/or by one C.sub.1-3 -alkoxy group, or a physiologically compatible salt thereof with an inorganic or organic base, have valuable properties as X-ray contrast agents.
    Type: Grant
    Filed: January 9, 1981
    Date of Patent: May 4, 1982
    Assignee: Schering, A.G.
    Inventors: Heinz Gries, Heinrich Pfeiffer, Ulrich Speck, Wolfgang Muetzel
  • Patent number: 4308341
    Abstract: There are disclosed an imaging composition, element and method featuring an aromatic dialdehyde that reacts with an exposure-generated amine to form a dye. The photographic speed of the reaction is improved by incorporating into the composition an imide capable of providing an ##STR1## moiety when heated.
    Type: Grant
    Filed: August 8, 1980
    Date of Patent: December 29, 1981
    Assignee: Eastman Kodak Company
    Inventor: Thap DoMinh
  • Patent number: 4304840
    Abstract: A method is disclosed of delineating a desired integrated circuit pattern upon a circuit substrate. According to the method, the copolymer poly(methyl alpha-chloroacrylate-co-methacrylonitrile) is formed by emulsion polymerization techniques. The copolymer is then dissolved in a spinning solvent that will dissolve the copolymer and form a viscous solution. The solution is applied to the surface of the substrate and the substrate spinned to form a smooth, uniform resist film of about 0.3 to 1.0 micron in thickness. The resist film is heated and the region of the resist film to be patterned then exposed to ionizing radiation until exposures greater than 1.5.times.10.sup.-5 C/cm.sup.2 are obtained. The exposed regions of the resist are then developed to the substrate.
    Type: Grant
    Filed: May 22, 1980
    Date of Patent: December 8, 1981
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: John N. Helbert, Charles U. Pittman, Jr.
  • Patent number: 4301237
    Abstract: An X-ray transparent mask (51) is comprised of a support ring (42) with a planar substrate stabilizer (41) thereon, the stabilizer having a plurality of apertures (43) therethrough, arranged in a "checkerboard" fashion. A thin X-ray transparent mask substrate (52) is placed over the stabilizer. (41), the substrate having X-ray absorptive metallized patterns (53) thereon which are aligned with the apertures (43). The mask (51) is positioned proximate a semiconductor wafer (56) having a photoresist coating (30) thereon. X-rays (14) are directed at the photoresist coating (30) through the apertures (43) to selectively expose the coating. The mask (51) is then indexed one aperture position and the remaining portion of coating (30) is exposed to the X-rays (14).
    Type: Grant
    Filed: September 29, 1980
    Date of Patent: November 17, 1981
    Assignee: Western Electric Co., Inc.
    Inventor: John A. Burns
  • Patent number: 4293640
    Abstract: A process for reducing patient and personnel hazards from exposure to X-radiation during diagnostic procedures, comprising irradiating a photographic emulsion to produce an underexposed radiograph, developing and fixing the radiograph and treating the underexposed processed radiograph in a one-step copper ion image enhancement composition to intensify the image profile to a level at least equivalent to a fully exposed radiograph and subsequently darkening the enhanced image by treatment in a one-step iron ion darkening composition to blacken the image profile. The copper ion image enhancement composition and subsequent iron ion darkening composition produces a darkened or blackened image profile as is found in conventional radiographs and enables a reduction in radiation exposure to patient and personnel up to 50% and more over what is generally regarded as the usual level of radiation for a given diagnostic radiographic examination.
    Type: Grant
    Filed: July 21, 1980
    Date of Patent: October 6, 1981
    Assignee: Minrad Corporation
    Inventor: Norman L. Weinberg
  • Patent number: 4273858
    Abstract: A resist material for micro-fabrication comprising a polymer in which the polymer backbone has thereon a moiety of the formula (I) ##STR1## wherein R represents a hydrogen atom, an alkyl group, an alkenyl group or an aryl group or an aralkyl group, the resist material being curable by electromagnetic radiation such as electron beams, X-rays or deep ultraviolet light with a wave length of less than about 3000A and being particularly suitable as a micro-fabrication resist material.
    Type: Grant
    Filed: July 19, 1978
    Date of Patent: June 16, 1981
    Assignee: Somar Manufacturing Co., Ltd.
    Inventors: Kohtaro Nagasawa, Hideo Ochi, Fujio Tanaka, Yumi Shibata
  • Patent number: 4267259
    Abstract: Radiation sensitive layers are x-ray exposed by providing a metal mask pattern on the layer through which the layer is exposed. The metal mask pattern is formed by applying a blanket metal layer to the radiation sensitive layer followed by an electron beam sensitive resist layer which is patterned by an electron beam exposure process. The exposed portions of the metal layer are then etched away to form the metal mask pattern.
    Type: Grant
    Filed: February 16, 1979
    Date of Patent: May 12, 1981
    Assignee: International Business Machines Corporation
    Inventors: Harald Bohlen, Johann Greschner, Werner Kulcke, Peter Nehmiz
  • Patent number: 4262083
    Abstract: Copolymers of an aziridine and sulfur dioxide are disclosed which are useful as positive radiation resists for use in electron beam and x-ray lithography.
    Type: Grant
    Filed: September 18, 1979
    Date of Patent: April 14, 1981
    Assignee: RCA Corporation
    Inventors: Thomas R. Pampalone, Nitin V. Desai, Eugene S. Poliniak
  • Patent number: 4262081
    Abstract: Radiation sensitive negative resists with requisite stability for dry processing of integrated circuits are polymerized from aromatic moieties containing halogen atoms. Halogen-aryl bridging, generally carbonaceous, increases sensitivity to radiation. Exemplary materials, copolymers prepared from aromatic and glycidyl methacrylate (GMA) comonomers, are suitable for direct processing of large-scale integrated circuits. While electron beam patterning is contemplated both for direct processing and mask making, radiation such as X-ray and deep u.v. may be used.
    Type: Grant
    Filed: November 21, 1979
    Date of Patent: April 14, 1981
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Murrae J. S. Bowden, Eugene D. Feit, Larry F. Thompson, Cletus W. Wilkins, Jr.
  • Patent number: 4262073
    Abstract: A recording medium is provided which is comprised of a substrate and a film of a polyacetylene sulfone on the surface of the substrate. The recording medium is especially useful in the microlithographic manufacture of electronic circuits using deep ultraviolet exposure.
    Type: Grant
    Filed: November 23, 1979
    Date of Patent: April 14, 1981
    Assignee: RCA Corporation
    Inventors: Thomas R. Pampalone, Emil J. Gavalchin
  • Patent number: 4260670
    Abstract: An X-ray transparent mask (51) is comprised of a support ring (42) with a planar substrate stabilizer (41) thereon, the stabilizer having a plurality of apertures (43) therethrough, arranged in a "checkerboard" fashion. A thin X-ray transparent mask substrate (52) is placed over the stabilizer (41), the substrate having X-ray absorptive metallized patterns (53) thereon which are aligned with the apertures (43). The mask (51) is positioned proximate a semiconductor wafer (56) having a photoresist coating (30) thereon. X-rays (14) are directed at the photoresist coating (30) through the apertures (43) to selectively expose the coating. The mask (51) is then indexed one aperture position and the remaining portion of coating (30) is exposed to the X-rays (14).
    Type: Grant
    Filed: July 12, 1979
    Date of Patent: April 7, 1981
    Assignee: Western Electric Company, Inc.
    Inventor: John A. Burns
  • Patent number: 4256825
    Abstract: A photographic element, comprising a photographic base carrying a light-sensitive photographic silver halide emulsion layer and a photosensitive non-silver halide layer in operative association with said silver halide layer, said non-silver halide layer containing a light-sensitive composition selected from the group consisting of diazotype compositions, vesicular compositions and photosensitive polymers.
    Type: Grant
    Filed: June 8, 1979
    Date of Patent: March 17, 1981
    Assignee: GAF Corporation
    Inventor: Frank J. Loprest
  • Patent number: 4256829
    Abstract: A method of manufacturing a microminiature solid-state device includes first and second exposure steps in which radiation-sensitive material on a solid-state substrate is exposed radiation through a mask pattern to define locations for localized processing. A local processing step between the first and second exposure steps causes an undesired dimensional distortion of the substrate surface in the plane of the substrate surface. This dimensional distortion is then reduced by adjusting the relative sizes of the area of the substrate surface and the area of the mask used in the second exposure step in an substantially uniform manner prior to the second exposure step. By adjusting the relative sizes of the substrate surface and mask areas in such a way as to compensate for the planar dimensional distortion induced in the first exposure step, such dimensional distortion can be substantially reduced.
    Type: Grant
    Filed: May 3, 1978
    Date of Patent: March 17, 1981
    Assignee: U.S. Philips Corporation
    Inventor: Peter J. Daniel
  • Patent number: 4254210
    Abstract: To reduce silver coating weight in photographic silver halide elements (e.g., medical X-ray films) the density of the silver image is increased by forming a black-toned, direct positive image in a photopolymer layer on the reverse side from the silver image.
    Type: Grant
    Filed: May 11, 1978
    Date of Patent: March 3, 1981
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Albert L. Van Stappen
  • Patent number: 4232110
    Abstract: A process of dry etching to form negative resist patterns is described. A host polymer is mixed with one or more monomers capable of being locked into place by electromagnetic radiation and is deposited as a film on a substrate. The film is then selectively irradiated, and then fixed by heating, or vacuum, or both, and etched by means of an oxygen plasma. The rate of removal is higher in the unirradiated region than in the irradiated region, yielding a negative resist pattern. A sensitizer may be added to allow use of various radiation wavelengths. The desirable properties of monomer and host polymer materials are discussed, and specific compositions given of aromatic monomers, silicon containing monomers, and chlorinated polymers.
    Type: Grant
    Filed: March 12, 1979
    Date of Patent: November 4, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Gary N. Taylor
  • Patent number: 4232116
    Abstract: Ultraviolet radiation sensitive photographic film material comprising a silver halide emulsion of at least 50 mole % silver chloride and a yellow filter dye over said silver halide emulsion layer.
    Type: Grant
    Filed: January 31, 1979
    Date of Patent: November 4, 1980
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Peter B. Jamieson
  • Patent number: 4215192
    Abstract: In order to obtain shorter exposure time and to obtain a longer life in x-ray lithography apparatus, an x-ray target made of tungsten is utilized and the apparatus operated to generate the tungsten M-line, this line being at a wavelength which will be absorbed by the resist normally used in lithography. To develop the resist, which was initially designed for use in an electron beam lithography, a developing method is used in which a initial short development with a high concentration is first carried out followed by a longer, full development with a concentration which is approximately the lowest at which complete development will take place.
    Type: Grant
    Filed: January 16, 1978
    Date of Patent: July 29, 1980
    Assignee: The Perkin-Elmer Corporation
    Inventor: William D. Buckley
  • Patent number: 4212936
    Abstract: A photographic element having at least two silver halide emulsion layers, one layer containing a colorless cyan-forming coupler which produces a negative image and the other layer containing a colored coupler which upon color development with a p-phenylene diamine developer produces a positive dye image of contrasting color to cyan, will produce a color contrast radiographic picture after exposure and development.
    Type: Grant
    Filed: November 25, 1977
    Date of Patent: July 15, 1980
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Claudio Giampieri