Showing papers on "Photomask published in 1984"

Dust cover superior in transparency for photomask reticle use and process for producing the same

Abstract: In a dust cover for photomask reticle purposes which consists essentially of a supporting frame and a thin film bonded to a surface of the frame, the dust cover is improved in transparency by constructing at least the outermost layers of the thin film with thin films of a fluoropolymer which exhibits an average transmittance of at least 90% for rays of wavelengths from 240 to 290 nm and an average transmittance of at least 93.5% for rays of wavelengths from 290 to 500 nm, when having a thickness of 10 μm, and has a refractive index of up to 1.42.

Apparatus for inspecting mask used for manufacturing integrated circuits

Abstract: @ A mask inspection apparatus is arranged to compare a measured data signal obtained by optically measuring a photomask with a design data signal representing an integrated circuit pattern so as to inspect defects of the photomask on which the integrated circuit pattern is drawn. To inspect the pattern area and its peripheral area of the mask in one step, a reference signal generator (48) in the mask inspection apparatus is arranged to generate a reference signal containing a predetermined additional data signal representing the peripheral area of the integrated circuit pattern, in addition to the design data signal representing the integrated circuit pattern. The reference signal is compared with the measured data signal of the pattern area and its peripheral area from a signal detector (43) by a defect detector (47).

Plasma etching apparatus

Abstract: PURPOSE:To prevent the irregularity of a dimension, by a method wherein the resist surface of a photomask is irradiated with monochromatic light during discomposition and the decrease of the resist film by discomposition is measured from the amount of reflected light. CONSTITUTION:A photomask 2 provided with a resist pattern is placed to the center of the treating tank for discomposition and plasma is generated from a high frequency power source 3. The resist film of the photomask is irradiated with light 5 at an arbitrary angle theta from a monochromatic light source 4 such as He-Ne laser. Reflected light is received by a light receiving element 7 such as photomultiplier to be converted to an electric signal. By this method, the irregularity of a dimension by discomposition is prevented.

Method for fabricating a photomask pattern

Abstract: A method for fabricating unit patterns each having the same shape and size for a semiconductor die on a photomask pattern area of a photomask. By designating a matrix having rows and columns for the unit patterns on the photomask pattern area, the fabrication is made in the order of two exposing modes. In the first exposing mode, the fabrication is made by exposing respectively an optical image for the unit pattern on selected several matrix elements placed as far as possible away from each other in the photomask pattern area; in the second exposing mode, the exposure of the unit pattern is made along the row of the matrix elements except for the elements which have been exposed in the first exposing mode, until the exposure for all unit patterns are made by shifting sequentially the exposure to the next row. These exposures of the unit patterns, thusly are made with vernier pattern producing overlapped vernier patterns when the exposures of the first and the second exposing modes are made. Thus, after all the unit patterns have been printed on the photomask base plate, an inspection of the positions of the unit patterns can be made by observing some of the overlapping vernier patterns and measuring the accumulated shears which are produced in the second exposing mode.

Improvement of mask-limited yield with a vote-taking lithographic scheme

Abstract: A lithographic technique which can significantly reduce the effect of photomask defects is investigated. It is based on exposures of multiple reticle fields containing identical patterns, and is especially suitable for 1 × wafer steppers. The principle, requirements, and initial experimental results of this method are presented.

Registering and exposing sheet substrates using photosensitive liquid

Abstract: A process is disclosed for the application of a photosensitive liquid between the substrate and the photomask during contact printing. The substrate and photomask are aligned in a hinged relationship.

Projection type light exposing device

Abstract: PURPOSE:To contrive improvement in working efficiency by a method wherein two sheets of semiconductor wafers are exposure-treated simultaneously for a sheet of photomask CONSTITUTION:A half mirror 14, which transmits and reflects the light irradiated from above a photomask, is transmitted in-between the photomask and the projetion lens 131 of the projection type exposing device A mirror 15, which reflects the reflected light coming from the mirror 14, and the second projection lens 132, which projects the light coming from the mirror 15, are arranged in parallel with said mirror 14, thereby enabling to simultaneously perform an exposure processing on two sheets of semiconductor wafers 171 and 172 pertaining to a sheet of reticle 16

Electron beam peripheral patterning of integrated circuits

Abstract: Silicon wafers are imprinted with microelectronic circuit patterns by firstithographing the outlines or peripheries of all circuit features of a given wafer level by means of a narrow line formed by direct-writing electron beam lithography utilizing a positive electron resist, then using proximity photoprinting to complete the lithography of that level using a positive photoresist and a photomask with oversized opaque areas so that the pattern edges on the wafer exposed to the flux passing through the photomask will fall within the peripheral lines formed by the electron beam.

Guide rail apparatus for positioning flat objects for microscopic examination

Abstract: A work station for photomask inspection includes a microscope and a movable stage positioned below the objective of the microscope. A rectangular frame of the stage surrounds a viewable area of the stage. Rail means are bolted onto the frame at spaced apart positions corresponding to the width of the photomask that is to be inspected so as to position the photomask therebetween. The rails have end stops that are positionable according to the length of the photomask for positioning the end edges of the photomask therebetween.

Production of color filter

Abstract: PURPOSE: To improve the degree of freedom for formation of a color filter and the mass productivity thereof by coating transparent electrodes with a resist material then patterning said material, removing the resist, coating the resist over the entire surface, patterning the resist and removing the remaining resist. CONSTITUTION: The patterned transparent electrodes 32aW32f are formed on a transparent substrate 31 and the resist material is further coated thereon and is patterned by using a photomask so that resist film remains only on the shaded part 47. The colored layer is formed only on part 48b, 48c, 48e, 48f of the electrodes 32b, 32c, 32e, 32f when electrodeposition painting is executed in this state. The filters are formed with all the optional patterns defined by the pattern of the photomask when cleaning, baking and resist removal are executed. The degree of freedom from the formation of the color filter and the mas productivity thereof by the electrodeposition painting method are thus considerably improved by the addition of a slight stage. COPYRIGHT: (C)1986,JPO&Japio

Method for inspection of photomask

Abstract: PURPOSE:To increase the reliability of photomask inspection by a method wherein a transparent film having film thickness of nlambda/4 (n: integral number, lambda: light- emission source wavelength) is formed in advance on a substrate, a mask pattern is reproduced on the upper surface of said transparent film, and a comparative detection is performed. CONSTITUTION:A resist film pattern 8 is reproduced on the substrate 1 using the photmask to be inspected, and a defect is detected by comparing the reflected light image coming from the two mask patterns of samd type located on the substrate. At that time, a transparent film 10 having the film thickness of nlambda/4 (n: integral number, lambda: light-emission source wavelength) is formed in advance on the substrate 1. As a result, the difference of quantity of light between the pattern 8 and the surface of the substrate 1 is increased, and a misjudgement can be eliminated even when a visual inspection is performed.

Apparatus for inspecting mask for use in manufacturing large scale integrated circuits

Abstract: A photomask (12) bearing a circuit pattern depicted thereon, which is used in manufacturing semiconductor integrated circuits, is exactly inspected, without being influenced by the geometrical distortion of the photomask. To this end, the positions of at least three position detecting marks on the photomask, which is placed on an X-Ytable (11), are optically detected. Using the detected positions of these marks, the geometrical distortion of the photomask is calculated. According to the detected distortion of the photomask, a compensation is made of the reference signal generated based on design pattern data, which is to be compared with a measured signal obtained by the optical measurement of the circuit pattern.

Laser working method

Abstract: PURPOSE:To perform laser working with high accuracy and extreme ease by forming a highly reflective thin film on the surface of a work, and forming a mask pattern consisting of a resist thereon then etching away the thin film along the pattern and irradiating a high output laser thereto. CONSTITUTION:A thin film 3 of Al or Au having high reflectivity to laser light is formed by a sputtering method or the like on the surface of a work 1. A resist 5 is coated thereon and after a photomask pattern is exposed thereon, the resist is developed to form the mask pattern of the resist. The film 3 is then etched to form the mask of the thin film, and the resist 5 is stripped. A high output laser 7 is finally irradiated on the surface thereof to work only the window 3' part of the thin film mask by the laser and the film 3 is removed. Machining, such as drilling or cutting and a surface heat treatment, such as annealing, are easily made possible by the adequate control of the laser output.

Cleaning method of photomask

Abstract: PURPOSE:To clean a photomask to be used as an original plate in photolithography without damaging the metallic film for light shielding, by dipping the photomask in a bath of a sulfuric acid or the like while applying a voltage between the photomask and the counter electrode thereof CONSTITUTION:A photomask 8 formed with a figured patternlike chromium film 12 on a glass substrate 10 provided with a light transmittable conductive film 11 is subjected to a cleaning treatment More specifically, the above-mentioned photomask 8 (a symbol 9 is a clip) and a platinum plate 14 are dipped perpendicularly in the sulfuric acid 2 in a cleaning tank 1 The acid 2 is heated to about 90-120 degC with a heater 3 and foam 15 of ozone-contg air is ejected through a blow pipe 5 and a blow-out port 6 into the acid 2 to generate a Caro's acid On the other hand, about 15-25V DC voltage is applied between the plate 14 (cathode) and a chromium film 12 (anode) by a power source 13 Therefore, the film 12 is immobilized by the oxide film formed on the surface thereof and since it is insoluble, only the foreign matter such as photoresist sticking on the mask 8 is dissolved away in the Caro's acid

Precured split hinge for photomask assembly

Abstract: Hinged glass photomask assemblies for photolithographic processes are disclosed wherein a flexible polymeric split hinge is used to join glass plates thereby providing for greater flexibility of the phototool.

Manufacturing device of semiconductor device

Abstract: PURPOSE:To obtain photo resist pattern without pinholes by developing and transferring mask pattern to the semiconductor wafers surface on which the photo resist is applied, thereby obtaining the predetermined photo resist pattern and by irradiating with ultraviolet rays thereto. CONSTITUTION:Semiconductor substrates which have been accommodated in a carrier 1 and have completed the processes up to the photomask transfer and exposure process are sent one by one to a developing apparatus 3 with the conveyor belt, then subjected to the predetermined development process therein for the patterning of photoresist film. Next, while the substrates 4, 4' 4'' are being sent with the conveyor belt 5, the photoresist pattern is exposed to the mercury lamps 6, 6' provided on the belts 5, 5'. Thereby the optical polymerization is caused to advance and accordingly etching resistivity can be enhanced in combination with the thermal polymerization in the next process. Finally, a multi- layer structure which does not generate separation of patterns can be obtained.

Photomask for fabrication of semiconductor device

Abstract: PURPOSE:To prevent heat strain of a photomask due to heat caused by transmission of intense exposure light, by superposing a material same as the photomask on a pattern face, and forming the image of dust on the mask at a position different from that of the pattern. CONSTITUTION:A plane pattern 32 is placed on a quartz glass 31, and a quartz glass 33 same in material as the glass 31 is further placed on the glass 31, and the glass 33 is joined with a low-melting junction glass 34 at the circumference to constitute a photomask. Therefore, even if dust 35 is attached to the surface of the glass 33, the image of the dust 35 is not attached to the resist by baking because the positions of formation of the images of the dust 35 and the pattern 32 are different from each other. Moreover, since the pattern face is interposed between the materials same in expansion coefft., heat strain is small even if intense exposure light is transmitted. The pattern 42 formed on the quartz glass 41 may be buried perfectly in the quartz glass by forming the quartz glass 43 and joining it with the glass 41 into one body.

An X-Ray Stepper

Abstract: With design rules for highly integrated circuits approaching or even attaining the sub-micron range, a mask aligner which is not working near its resolution limit is needed in order to provide enough process latitude. A candidate for this kind of machine is an x-ray stepper operating at a safe gap between mask and wafer and using a synchrotron radiation source. A mechanical stepping system, a gap setting mecnanism and an autoalignment scheme, in addition to the adaptation to synchrotron sources are described. An outlook on the economical advantages of this kind of lithography versus optical steppers is given.

Photographic process for applying phosphor pattern to color crt shadow mask

Abstract: Phosphor characters to supply feedback information for an automatic convergence system are applied to the gun side of the shadow mask of a color cathode ray tube by a method of applying layers of a positive-working photoresist and phosphor, exposing the layers through a positive photomask, back exposing to clear the shadow mask apertures, developing to remove the exposed areas, and baking to remove the photoresist.

Equipment for management of incomings and outgoings of photomask

Abstract: PURPOSE:To manage the incomings and outgoings of photomasks quickly and accurately and suppress the generation of the dust as low as possible by providing a container shelf in which mask case containers are loaded, a transfer equipment and a computer. CONSTITUTION:When a type and a process of a product is specified by operating keys of an input part or an operation panel 33 of a photomask managing computer 50, the managing computor 50 retrieves the information stored in itself and finds out the location of a container 10 and a mask case 11 and gives instructions to a transfer control computer of a mating and anmating equipment 30. The transfer control computer drives and controls a transfer equipment 40 and the container 10 is inserted into the mating and anmating equipment 30 and the mask case 11 in which the indicated mask is contained is pushed up. Whenever a photomask is taken out and put in, the managing computer 50 renews the photomask information.

Photomask material and photomask

Abstract: PURPOSE:To prevent deterioration of light transmittance, to reduce reflectance, and to raise glass strength, by forming a glass tarnish preventing layer on both sides of a glass substrate or on one side opposite to a hard mask formed layer to prevent bluing tarnish on the surface of the glass substrate. CONSTITUTION:Tarnish preventing layers 3, 3' are formed on both sides of the substrate 4 of a soda lime glass, alumina silicate glass, or the like, or on one side opposite to a hard mask formed layer by vapor depositing a material having characteristics small in refractive index, high in surface hardness, almost transparent to light from a baking light source, and unattacable by an etchant. A Cr layer 1, a chromium oxide layer 2, and a photoresist layer 5 are formed on the layer 3' or the substrate 4 to form a photomask R. The layers 3, 3' prevent the phenomenon of bluing tarnish that the substrate 4 reacts with moisture in the air and forms a number of fine crystal group, and when they grow coarse, they opacify the outside surface of the photomask a little, deteriorate transmittance, cause local corrosion and defects on the mask pattern.

Photomask for manufacture of semiconductor device

Abstract: PURPOSE:To minimize the effect of a photoresist film for ion-implantation against the ion-implantation quantity and its distribution by designing the photomask pattern in such a manner that the photoresist film for ion-implantation has the minimum necessary area. CONSTITUTION:In the figure showing a photomask for a semiconductor device, 1 is a semiconductor chip, 3 is each of ion-implantation domains and 7 is each of photoresist films composing a mask for ion-implantation. The photomask pattern is such that the films 7 are formed to have the minimum necessary area only on the domains which must be covered from ion-implantation and all the photoresist films on the domains to which ion-implantation has no harmful effect are removed. With this constitution, the effect of the photoresist films for ion- implantation can be minimized and a semiconductor device with stability and reproducibility can be realized.

Method of fabricating a photomask pattern

Abstract: of EP0138602A method of fabricating a photomask pattern (210), having a matrix array of unit patterns (201) on a photomask (200), involves two exposure modes. In a first exposure mode selected matrix locations (211 to 214) are exposed to an optical image for forming a unit pattern. In a second exposure mode the other matrix locations are exposed to the optical image in a regular ordered sequence by step-and-repeat printing (D, E, F, G, H). Each unit pattern has a vernier pattern. Vernier patterns of adjacent unit patterns overlap (230) to provide for measurement of shear. The employment of the two exposure modes allows accumulated printing shear to be measured from overlapping verniers patterns provided at locations (e, f, g, h) where unit patterns formed in the first and second modes respectively are adjacent.

Reduction projecting and exposing method

Abstract: PURPOSE:To minimize the influence of dust sticking to a mask, by using plural masks and reducing transmitted energy per mask, and exposing the same position of a substrate several times. CONSTITUTION:An image obtained by a photomask 1 is reduced by a lens system 2 and projected on the substrate 3 by one shot to complete an exposure pattern. N Sets of masks 1 having the same pattern are used to reduce the amount of exposure per mask to 1/N as great as the basic amount of exposure and the substrate 3 is exposed to a one-shot image; and the substrate 3 is moved in an x-axis and a y-axis direction to form exposure patterns 4a-4c over the entire surface of the substrate successively for entire-surface exposure. Further, a prepared photomask 1 is replaced and the same operation is repeated by N times for superposition exposure. In this case, plural lens systems may be used to perform plural exposure shots simultaneously or to superpose images of those lens systems optically. Thus, the influence of dust sticking to a mask is minimized as much as possible.

Photomask for microfabrication

Abstract: PURPOSE:To solve problems of deficiency of fabrication demensional precision and resolution due to roughness of the surface of a wafer, by coating the surface of a photomask with an elastic thin polymer film. CONSTITUTION:The substrate 1 coated with a 50-1nm thick patterned mask material 2 is further coated with a polymer, such as styrene-butadiene copolymer rubber, transparent for UV rays, resembling the substrate 1 or the photomask in refractive index, and dried to form a thin polymer film 3 of 3-5mum thickness. Then, it is exposed to plasma of a fluorine compd., such as CF4 or C3F8 or a silicon compd., such as SiH4 or SiF4, to give peelability to the surface of the film 3. As a result, lowering of semiconductor production yield due to stains on the photoresist or the photomask or abrasion of the photomask can be prevented.

Mask for manufacturing semiconductor device

Abstract: PURPOSE:To improve accuracy of a photomask and to enable application to a large-sized semiconductor wafer by dividing whole pattern to be formed in the semiconductor wafer into plural number and providing a part of pattern in a mask member. CONSTITUTION:A pattern to be formed in the semiconductor pattern 8 is divided and formed in the first and the second photomasks 1A, 1B. A pattern 3 of the first photomask 3A is transferred to (y) side of the wafer 8 using a mask fitting pattern 5 and a pattern 5B of the wafer 8. Then, the mask 1A is removed and the second photomask 1B is placed, and after fitting the mask, transferred to (x) side of the wafer 8. In this way, tolerance of the part that constitutes pattern area of the mask is improved, and accuracy of the mask can be improved. Accordingly, a mask applicable to a large-sized semiconductor wafer can be formed.

Projection type mask aligner

Abstract: PURPOSE:To reduce the frequency of changing a photomask setting the necessary pattern easily by a method wherein the surface of wafer or the like can be exposed with a plurality of photomasks by an identical projection exposure system and a mask selection means is provided to the optical system of each photomask. CONSTITUTION:A wafer 1, which is placed on a stage 2 and whose surface is coated by the prescribed photoresist, is moved along the horizontal X and Y directions by the stage 2. On the other hand, photomasks 3, 4, which are formed to the patterns different to each other, are supported at the positions perpendicular to each other by holders 5, 6 and illuminated by the light source lamps 7, 8. Then, a contracting type projection optical system 9 is provided to the light axis of one photomask 3 and the wafer 1 and a half mirror 10 is provided to the cross point of that light axis and the light axis of another photomask 4. Shutters 11, 12, which can be operated individually, are provided to the light paths of those photomasks 3, 4.

Method and device for washing photomask

Abstract: PURPOSE:To perfectly remove attached matters of >=3mum size and to prevent stains, etc. during drying of a washing soln. by wetting a photomask with an electrolytic soln., showing it with an alcohol type org. solvent, cleaning it with fluorinated hydrocarbon vapor, and drying it. CONSTITUTION:In an electrolytic soln. vessel 100, a photomask 10 is washed with aq. ammonia 2 filtered with a filter 16 and having prescribed purity, and thereafter, the use of the aq. ammonia 2 prevents electrification of the photomask 10, and attachment of dust, etc. perfectly in the following steps. In a shower vessel 200, isopropanol 9 is sprayed on the photomask 10 to substitute isopropanol 9 for the aq. ammonia 2 and to help the next drying step. In a vapor vessel 300, the photomask 10 is dried perfectly in a short time by once immersing it in trichlorotrifluoroethane 13 vapor and taking it out.

Photomask pattern inspection

Abstract: @ For inspecting the arrangement of unit patterns (2A to 2F; 41) on a photomask, the unit patterns being intended to have having the same shape and size and to be printed repeatedly with equal intervals on the photomask; shear-detecting-patterns (3a to 3c) are provided on each unit pattern so that pairs of adjacent shear-detecting patterns belonging to adjacent unit patterns form combined-patterns (51 to 53, 61 go 63,71 to 73;81 to 86, 91 to 96). In a group of such combined-patterns all the combined-patterns should have the same shape and size. One combined-pattern of the group is designated a standard-pattern and comparison is effected between the standard-pattern and another combined pattern of the group. The comparison yields a difference amount from which it is determined whether the combined-pattern arrangement in the group is correct.

Method and apparatus for inspecting a photomask reticle for semiconductor device fabrication

Abstract: @ An inspection method of a photomask reticle for the fabrication of a semiconductor device such as a die having a first pattern which has an individual shape and a plurality of second patterns each having a same shape and size, combining a method of a database inspection and a method of a pattern comparing inspection. The method of the database inspection is applied to the first pattern and a pattern selected randomly from the second patterns, The database inspection can be performed comparing with the inspection data derived from the designing data for the fabrication of the photomask reticle by such as an improved reticle tester which can exclude the second patterns except the pattern selected from the second patterns. The second patterns except the selected pattern are inspected by the method of the mask comparing inspection comparing with the selected pattern which has already inspected by the database inspection. Applying the present invention, the volume of the store medium for the data and time to inspect the photomask reticle can be reduced to as little as one fourth of those in the prior art inspection method, keeping high accuracy of the photomask reticle inspection.