EP0670052A1 - Photolithographie par batterie d'objectifs - Google Patents

Photolithographie par batterie d'objectifs

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Publication number
EP0670052A1
EP0670052A1 EP94906428A EP94906428A EP0670052A1 EP 0670052 A1 EP0670052 A1 EP 0670052A1 EP 94906428 A EP94906428 A EP 94906428A EP 94906428 A EP94906428 A EP 94906428A EP 0670052 A1 EP0670052 A1 EP 0670052A1
Authority
EP
European Patent Office
Prior art keywords
array
lens
image
field
light
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP94906428A
Other languages
German (de)
English (en)
Other versions
EP0670052A4 (fr
Inventor
Lithography Inc. Hugle
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
HUGLE LITHOGRAPHY Inc
Original Assignee
Individual
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Filing date
Publication date
Priority claimed from GB929224080A external-priority patent/GB9224080D0/en
Priority claimed from US08/114,732 external-priority patent/US5517279A/en
Application filed by Individual filed Critical Individual
Publication of EP0670052A1 publication Critical patent/EP0670052A1/fr
Publication of EP0670052A4 publication Critical patent/EP0670052A4/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/70—Microphotolithographic exposure; Apparatus therefor
    • G03F7/70691—Handling of masks or workpieces
    • G03F7/70791—Large workpieces, e.g. glass substrates for flat panel displays or solar panels
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/32—Projection printing apparatus, e.g. enlarger, copying camera
    • G03B27/44—Projection printing apparatus, e.g. enlarger, copying camera for multiple copying of the same original at the same time
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/0006—Arrays
    • G02B3/0037—Arrays characterized by the distribution or form of lenses
    • G02B3/0056—Arrays characterized by the distribution or form of lenses arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/18—Diffraction gratings
    • G02B5/1876—Diffractive Fresnel lenses; Zone plates; Kinoforms
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/18—Diffraction gratings
    • G02B5/1876—Diffractive Fresnel lenses; Zone plates; Kinoforms
    • G02B5/188—Plurality of such optical elements formed in or on a supporting substrate
    • G02B5/1885—Arranged as a periodic array
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/0005—Production of optical devices or components in so far as characterised by the lithographic processes or materials used therefor
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/20—Exposure; Apparatus therefor
    • G03F7/2002—Exposure; Apparatus therefor with visible light or UV light, through an original having an opaque pattern on a transparent support, e.g. film printing, projection printing; by reflection of visible or UV light from an original such as a printed image
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/70—Microphotolithographic exposure; Apparatus therefor
    • G03F7/70216—Mask projection systems
    • G03F7/70275—Multiple projection paths, e.g. array of projection systems, microlens projection systems or tandem projection systems
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/70—Microphotolithographic exposure; Apparatus therefor
    • G03F7/70216—Mask projection systems
    • G03F7/70316—Details of optical elements, e.g. of Bragg reflectors, extreme ultraviolet [EUV] multilayer or bilayer mirrors or diffractive optical elements
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/70—Microphotolithographic exposure; Apparatus therefor
    • G03F7/70425—Imaging strategies, e.g. for increasing throughput or resolution, printing product fields larger than the image field or compensating lithography- or non-lithography errors, e.g. proximity correction, mix-and-match, stitching or double patterning
    • G03F7/70475—Stitching, i.e. connecting image fields to produce a device field, the field occupied by a device such as a memory chip, processor chip, CCD, flat panel display
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/0006—Arrays
    • G02B3/0012—Arrays characterised by the manufacturing method
    • G02B3/0018—Reflow, i.e. characterized by the step of melting microstructures to form curved surfaces, e.g. manufacturing of moulds and surfaces for transfer etching
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/0006—Arrays
    • G02B3/0037—Arrays characterized by the distribution or form of lenses
    • G02B3/0062—Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between

Definitions

  • This invention is concerned generally with microimaging and concerned specifically with photolithography using lens arrays.
  • Microlithography has a long history and has provided benefits to many fields. Those familliar with the very tedius and time consuming "wire-wrap" methods can fully appreciate the power of printed circuit technologies. It has now become possible using microlithography methods, to create several million transistors in an area smaller than a square centimeter. Mechanical devices also have enjoyed spectacular advances. It was recently reported in the Journal of Micromechanical Devices that a fully operational motor that is only tens of microns in width can be made using techniques of microlithography. These advances have made the visions depicted in the fictional movie "Innerspace” where microrobotic machines were injected into humans to perform operations on a microscopic level, into something less of a dream and infinitely closer to a reality.
  • microlithography Projection of microimages is common for the manufacturing processes of microdevices including both electric and mechanical microdevices. These include, but are not limited to: electronic type devices such as micro integrated circuits and flat panel display devices, and physical devices such as surface acoustic wave devices, micromotors and other micromechanical devices. Modern microlithography processes sometimes require projection of light images (photolithography) having features as small as, or even smaller than one micrometer. Images for microlithography applications having such small features are generally produced with large lenses in photolithography projection machines.
  • a popular exposure tool for projecting images for photolithographic applications is called a "stepper machine".
  • a stepper machine generally has a very precise large lens with a high numeric aperture.
  • Some stepper machines are capable of faithfully reproducing images with features as small as .5 microns. Abberations, limit the useful field-of-view of stepper machines to a circular area of a few centimeters in diameter.
  • FPD Flat Panel Display
  • stepper image fields are projected in sequential exposures immediately next to each other.
  • This method requires a displacement of the lens with respect to the device substrate that is being printed, and therefore requires some very sophisticated motion and alignment equipment.
  • the exposure steps and move steps are repeated until the entire surface of device substrate is exposed. In this way, a large area device can be "built- up" with a multiplicity of exposures of a single, area-limited stepper field.
  • step-and-repeat has been the preferred method of microlithography to date for even large devices like FPDs.
  • the use of stepper machines has resulted in unacceptably low throughput and yield problems.
  • Production on a mass scale can only be economical with an exposure technique that can improve both the throughput and the yield that are currently known in the step-and-repeat methods.
  • a well known method of photolithography for very large areas is called "contact printing".
  • Contact printing does not suffer from field size limitations, but has very bad contamination problems. It is a problem to replace expensive large area photomasks which need to be replaced frequently due to damage caused by contact. Contact printing therefore is not currently considered a feasible alternative.
  • Still another method of large area exposure devices includes holographic photomasks which do not require lenses to form images. Holographic methods usually combine a photomask and an imaging means into a single device. These methods are quite elaborate and have yet to mature to the stage where production manufacturing is practical. Canon corporation offers lens imaging with scanning in one dimension and stepping in an orthogonal direction. A device produced by MRS Technology, Inc.
  • a Panel PrinterTM is a photolithography device which specifically built for very large area photolithography.
  • the device of MRS Technology, Inc. called a "stitching aligner". Although it is an advanced type of stepper, it also suffers from "stitching" type alignment errors.
  • a device developed by Ultratech stepper company employs a mirror for reflective type imaging optics and is quite successful in producing some special advantages such as ultra high resolution. However their Markel-Dyson imager is not suited for large areas. All of the photolithography systems mentioned are deficient in their ability to achieve large field, efficient imagers. They can not accomplish the advantages of the current invention and they are not effective replacements thereof.
  • a unique optical device with special imaging properties is known as a lens array.
  • a lens array is an arrangement of a plurality of lenses adjacent to each other in a plane with each of their optical axis perpendicular thereto.
  • MIT Lincoln Laboratory
  • ion etching having numeric apertures from 0.25 to 0.5 are described in a paper published by Leger, Scott, and Neldkamp, in Applied Physics Letters, vol 52 pages 1771-1773 in the
  • Refractive type microlens arrays are known and are simple to fabricate and the following are examples thereof: 1) NSG America inc. 2-d microlens array produced by photolithography and ion-exchange having a numeric aperture of 0.37. 2) CORNING shperical microlens arrays produced directly from glass by a photolytic process, NA ⁇ 0.35 published in Applied Optics, vol 27, 476-479 1988. and 3) NPL National Physical
  • BODs binary optical devices
  • Binary optical devices can be designed with optical properties that could not be obtained with conventional refractive type spherical optics. For example, it is easy to approximate a lens of parabolic shape having little or no geometric aberrations found in spherical devices. BODs are known by experts to be used for optical interconnects, aberration correction, computer vision, optical multiplexers, and even microsurgery of the human eye.
  • BODs Uses of BODs in array arrangements are described in a paper published in Scientific America by Neldkamp and McHugh, two of the pioneers of binary optics. However, previous to the present disclosure, it was not anticipated that BODs could be used to make even better microlithography tools. It is now possible to provide superior photolithography exposure tools which use techniques of lens array optical imaging.
  • an array of microlenses can be used as a photolithography exposure tool to project image information of a photomask onto an image field of very large area.
  • Many microdevices have a repetitive and discrete nature with respect to some unit element. For example, each pixel of a multi-million pixel flat panel display may be identical in circuit geometry. The repetitive and discrete nature of microdevices lends itself well to the imaging properties particular to lens arrays. Each lens of the array can be made to correspond to some unitary element of a particular microdevice.
  • the lens array can serve well. If the repetitive and discrete nature of microdevices is well matched with the repetitive and discrete properties of a lens array, the image field demarcations can be strategically placed to have minimal or no effect on a finished device.
  • an important design step is to define a "unitary element". Using lens arrays for photolithography applications may imply design rules that are unique to array photolithography, but the new rules will be a small price to pay for the advantages returned. It is also possible that those new rules will yield new design advantages.
  • a unitary element of a photomask pattern is some sub-area that is repeated over the entire device.
  • a unitary element can be defined by the image field limits of a single lens thereof.
  • Lens arrays can be designed to have different cell size, shapes and configurations to match the geometries of various devices. Depending upon the discretization and repetitivity of a particular device, the unit cell characteristics of a lens array would be designed to accommodate the geometry features of that particular device.
  • Dividing the image of a microdevice into subsections that can be imaged simultaneously is new to the art. Since an array can be comprised of a plurality of microlenses in a planar arrangement, arrays provide for a large area imaging. It is now possible to make a single exposure over a comparatively large area, thereby eliminating step-and-repeat operations and thereby reducing required exposure times for large area devices.
  • lens arrays can be adapted to address substrate shrinkage problems suffered by current microlithography systems.
  • an obvious case against using arrays could be made by suggesting that each unit lens of the array also has a limited image field, the detailed disclosure that follows describes methodologies that recognizes this specific limitation and provides clever solutions for it. Indeed it is a daunting task to have a continuous image over a large area using lens arrays; the following disclosure directly addresses this issue.
  • figure one is a representation of how a multilayer binary optical device can be used to represent a lens
  • figure two shows three alternative arrangements of lens elements in an array
  • figure three is an optical schematic drawing that shows simple imaging of a photomask of multiple images onto an image field through an array of lenses in a lens array plane
  • figure four shows that image inversion properties occur within each lens cell
  • figure five shows an array image comparison with an image from a conventional lens image
  • figure six is an exploded view of an example of a particular flat panel display device, an AMLCD, that can be manufactured with methods and devices of the invention
  • figure seven shows possible steps between images and the communication possible between pixels provided by field shifted layers
  • figure eight shows a magnification schematic, it is possible to achieve reduction (magnification ⁇ 1) but this is not shown.
  • figure nine shows field overlap that can be used to facilitate interconnections between adjacent image fields; figure ten show how four adjacent field images can be made to form a simple continuous image; figure eleven shows a complex image that is continuous over a multiplicity of cells and the mask that is required to generate such image; figure twelve shows the use of a "field lens" to aperture single mask fields; figure thirteen shows the conformal mapping that is possible with binary optics "lenses".
  • an apparatus for and method of photolithographic exposure there is provided an apparatus for and method of photolithographic exposure. It will be appreciated that each of the embodiments described include both an apparatus and method and that the apparatus and method of one preferred embodiment may be different than the apparatus and method of another embodiment.
  • a machine for photolithography typically includes substrate handling systems, alignment mechanisms, a light source, an imaging means and a photomask.
  • the imaging means of the invention has many imaging properties unique to arrays and very useful for photolithography applications.
  • a plurality of lenses arranged in a two dimensional array can be realized by dividing a single large substrate into many subsections, each subsection thereby defining unitary lens areas.
  • a lens can be constructed using known techniques. For example, it is possible to create gradient index GRIN type lens by arrangement of the index of refraction profile of the substrate material between a first surface of the substrate and a second surface thereof. Alternatively, it is possible to heat a substrate with a previously preparred surface such that the surface tension of each unit lens areas forms a spherical surface therein.
  • BODs Binary optical device BOD physics provide added advantages that are expected to provide favorable results for photolithography techniques and it is currently anticipated that BODs will be the preferred method to fabricate lens arrays.
  • BODs have been used: as imagers without sphereical abberrations, in combination with refractive type optics to correct chromatic abberation, and as optical elements with complex mapping properties.
  • BODs work on principles of diffraction in comparison to conventional optics which rely on refraction to bend rays.
  • a BOD can be made to by creating multi-level, or "staircase" structure using common etching techniques.
  • a diffractive lens similar to a Fresnel zone plate is effective for creating images similar to refractive optics.
  • the drawing figure 1 shows a BOD lens that has been etched into some bulk material.
  • a circular blank is etched with a series of concentric staircase patterns.
  • Each staircase proceeding out from the center is made successively steeper and closer to its neighbor.
  • the steeper staircases bend the light by ever increasing angles so that light passing through the edges of the lens is focused to the same part as light passing through the center.
  • at least three methods of forming lens arrays are well known in the art and that the details of array manufacture are left for other presentations.
  • An array of lenses can be embodied in several ways to meet various repetive properties.
  • the three drawings of figure two show how the lenses can be put on centers that define triangular, square, or rectangular repetitive nature. Many other possibilities can be easily used to support various design rules.
  • a photomask sometimes called a reticle, is generally a light mask with aperture stops and apertures that serves to convert a uniform light field of some source to a spatially patterned light field.
  • a photomask is a substantially flat glass substrate with a pattern of chromium having been evaporated thereon. The pattern of the chromium defines the circuitry or other structure to be transmitted to the circuit substrate in a photolithographic process.
  • a very specialized mask technology has stops and apertures where the apertures are of varying types. The phase of a light field wavefront passing through some apertures is shifted usually by a high index transparent material. "Phase shift" masks will work very well with the lens array technology and lens array system is expected to benefit from phase shift mask technologies.
  • the spacing of the lens array with respect to the object (photomask pattern) and image (at the substrate surface) can follow the same rules of imaging with conventional single lenses whereby the size of the image is the same as the size of the photomask pattern when the lens plane is placed between and equidistant from the object and image.
  • An example of one to one imaging is shown in drawing figure 3. It is important to note that there is an image inversion symmetric about the optical axis of each lens of the array and the pattern of the photomask will necessarily be required to account for this image inversion.
  • the pattern on a photomask of the art is therefore likely to be different than the pattern on a photomask of the invention and photomasks to be used with lens arrays may have a new set of corresponding design rules.
  • an apparatus for photolithographic exposure which comprises a lens array
  • the apparatus for imaging a photomask pattern onto a substrate comprises a plurality of lenses arranged in a two dimensional array.
  • this device is one example of many possible FPDs and of many possible microdevices that can benefit from the various features, aspects and advantages of the invention. It is not intended that the use of the invention be limited to this specific device; and the contrary is explicitly stated here: the invention will be useful for all photolithography applications which yield various microdevices having properties that are compatible with the imaging characteristics of lens array devices.
  • the invention is particularly useful for the production of active matrix liquid crystal displays which is a type of high performance, high information density display.
  • the invention can image active circuit patterns, which is a critical step in the production process of AMLCDs.
  • AMLCD is the FPD technology which best combines rapid response rate, low power consumption, wide viewing angle and long lifetime while providing contrast, resolution and color quality that generally rivals the best cathode ray tubes and surpasses passive matrix displays.
  • AMLCDs are now used in high end laptop and notebook computers, camcorder viewfinders and miniature color televisions.
  • the principle disadvantage of AMLCDs is the high production cost; this invention aims to remedy that problem.
  • An AMLCD screen can be a pile of planar substrates including: a light field polarizing element, a circuit substrate, a liquid crystal solution, color filters, and a second polarizing element.
  • the circuit substrate is a complex electronic device comprised of high density microstructure of circuit lines and electronic components.
  • the entire display can be made of millions of pixels each being similar or identical in structure to the others.
  • Light from a source can be modulated by the device as the liquid crystal material can variably rotate the polarization state of the light propagating therethrough.
  • the circuits of each pixel independently control the transmission of light through that pixel thereby creating a light pattern.
  • Manufacturing the circuit substrate of an AMLCD requires the highly accurate printing onto a substrate of the high density microstructure which may be many layers in depth with their individual layers and interconnects.
  • a material such as indium tin oxide, a transparent metal
  • a coating of light-sensitive photoresist chemical is applied.
  • a series of photomask images is then successively imaged onto the photoresist by a photolithographic system, using a lens array. Each pattern exposed onto the photoresist can then be developed and etched. Developing removes the exposed photoresist pattern, while unexposed photoresist remains on the substrate impressing the image of the photomask onto the substrate.
  • etching then removes the metal layer in the exposed areas thereby transmitting the image into the metal layer thus creating the AMLCD circuitry and electronic structure.
  • an insulating material such as silicon nitride
  • a coating of photoresist is added and the plate is exposed, developed and etched. These steps are typically repeated five to seven times, or as many times as there are layers required to realize the electronic devices such as transistors and the electronic circuitry required to support those devices.
  • the invention provides an excellent means for the exposure of the photoresist and for cooperation of images of the various layers which make-up the device. Because the AMLCD has multiple exposures and each exposure is over a very large area, a lens array exposure tool with large area capability is a possible solution for the current limits face in the industry.
  • the required electronics to drive a single pixel can be imaged as self contained circuits that are continuous, within a field-of-view of a single lens unit.
  • the exposures of the final layers are made with a displacement of the lens array. Before the exposure, the lens array is displaced some fraction of a cell width such that the image field of a previous layer overlaps the image fields of a sequential layer.
  • image sub-fields with patterns therein can be made to overlap such that the patterns in one image sub-field are in good communication with the patterns of an adjacent image sub-field.
  • An example of this geometry is shown in figure 9.
  • the image shown in the figure is an exaggeration of an interconnect arrangement that could prevent even gross adjacent field image errors. It is further possible to have a very small overlap zone and intersecting geometries without special terminations that are oversized as is shown in the drawing. It the limiting case, a mask could be carefully designed to have overlap regions but the final image produced could be continuous over the entire area of the circuit substrate.
  • Lens array magnification can be achieved the same way as simple lens magnification where the ratio of the distances between the photomask (object) and the circuit substrate (image) each with respect to the lens plane, defines the value of the magnification.
  • An optical schematic is shown as figure 8 which is a lens array in a magnification orientation.
  • An array of field lenses can be placed between an imaging lens array and the photomask to collimate the light coming from the photomask. Light that does not enter the aperture of the correct field lens gets lost in the system instead of becoming imaged as can be possible without field lenses.
  • Using a plurality of arrays located sequentially in space with respect to a light field passing therethrough is considered to be a subset of simpler embodiments of the invention.
  • Another reason to combine several lens arrays in series is to correct for the effect of chromatic aberration; again, this is well know in the optics field and this effect translates nicely to the array photolithography systems. There are other possibilities of using multiple lenses in series to achieve imaging objectives and these are known from common geometrical optics.
  • a common problem experienced in the manufacture of large area devices is substrate shrinkage caused by processing environments between printing sucsessive layers. If a layer is first printed and then processed in etching and evaporating environments, the entire substrate can shrink. A following layer's image may not align well or be sized correctly with respect to the image of the first layer. Shrinkage is sometimes predicable and in that case the image can be compensated for in the construction of the photomask patterns. But shrinkage is not always exact and consistent and may vary from day-to-day. Some systems of the art respond by slight magnification changes.
  • Binary optical devices can be used to create a lens whose "optic axis" is not a simple line as is the axis of conventional optical devices, but rather a plane segment, a conic section or even a lens with an imaginary axis; imaginary in the mathamatical sense.
  • a lens can be designed such that it also has an irregularly shaped image field or provides some complex mapping of an object field to an image field. Such translation is sometimes called conformal mapping in mathematics.
  • the image field of conventional lenses is symmetric about the lens axis and is defined as a circle. Since circles are awkward in some geometries, circular image fields are frequently apertured to a square having corners defined by points on the circle. The image areas outside the bounds of the square but inside the circle represent areas of wasted space. In lens array systems, those areas of wasted space may interfere with images of adjacent lenses if the images are to be in close proximity. This is an artifact of axially symmetric optics and can be eliminated in BOD designs. BODs can be designed to have any shape image field. If some microdevice structure requires a group of squares next to a rectangle section next to it, these areas can be addressed with single BOD lenses. A rectangular field is impossible to achieve with conventional optics without aperturing, yet is quite simple with binary optical devices.
  • Photomasks are sometimes made with electron beam machines and they produce images with axially symetric artifacts.
  • a photomask may easily generate a pattern free from erros that is radially symmetric but an image having non-radial symmetry would necessarily suffer from errors intrinsic in the electron beam writing process.
  • Radially symetric image patterns flawlessly generated with an electron beam machine could then be converted into rectangularly symmetric images with a BOD that maps concentric circles to parallel lines.
  • Figure thirteen "A” shows a radial pattern that can be flawlessly generated by an electron gun photomask writing machine.
  • Figure thirteen "B” shows a BOD used to image the pattern of thirteen "A”.
  • Figure thirteen "C” shows the resultant rectangularly symmetric pattern which could not be generated without some asymmetric error caused by the electron beam writing system and transferred to the circuit substrate through photolithography.
  • conformal mapping techniques it is possible to have many translations that result in otherwise impossible imaging patterns and therefore otherwise impossible devices.
  • Image geometries that could not be realized in conventional optical systems can be easily generated with binary optical device imagers.

Abstract

Les techniques de microlithographie ont apporté le moyen de mettre au point un grand nombre de dispositifs utiles de microcircuits, qui ont rendu possible l'ère de l'ordinateur, ainsi que des dispositifs micromécaniques tels que des moteurs ne présentant que quelques dizaines de microns de largeur. La nouvelle utilisation d'un tel dispositif miniature présenté ici constitue un 'juste retour' à l'art de la microlithographie par la contribution notable qu'elle apporte à cet art. Le dispositif visé est un dispositif miniature unique réalisé selon les techniques avancées de la microlithographie, qui peut être utilisé comme un nouvel instrument d'exposition en microlithographie. Une batterie d'objectifs d'une épaisseur pouvant ne représenter que le quarantième d'une feuille de papier ordinaire comporte néanmoins un ensemble d'objectifs optiques assez puissant pour remplacer des optiques de précision complexes, volumineux et coûtant des millions de dollars. Une telle batterie d'objectifs peut être réalisée avec un dispositif optique binaire et selon d'autres techniques. Ayant une surface et un champ de vision illimités, une telle batterie peut servir d'instrument d'exposition à des dispositifs miniaturisés de grande surface, tels que des écrans de panneaux plans, sans qu'il soit nécessaire de recourir aux opérations par étapes et répétitives qui limitent considérablement le rendement dans la production moderne.
EP94906428A 1992-11-17 1993-11-15 Photolithographie par batterie d'objectifs. Withdrawn EP0670052A4 (fr)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
GB9224080 1992-11-17
GB929224080A GB9224080D0 (en) 1992-11-17 1992-11-17 Imaging mask patterns
US08/114,732 US5517279A (en) 1993-08-30 1993-08-30 Lens array photolithography
US114732 1993-08-30
PCT/US1993/010945 WO1994011781A1 (fr) 1992-11-17 1993-11-15 Photolithographie par batterie d'objectifs

Publications (2)

Publication Number Publication Date
EP0670052A1 true EP0670052A1 (fr) 1995-09-06
EP0670052A4 EP0670052A4 (fr) 1995-10-25

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JP (1) JP3443627B2 (fr)
KR (1) KR100310787B1 (fr)
AU (1) AU6013594A (fr)
WO (1) WO1994011781A1 (fr)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19520563A1 (de) * 1995-06-06 1996-12-12 Zeiss Carl Fa Beleuchtungseinrichtung für ein Projektions-Mikrolithographie-Gerät
US5684566A (en) * 1995-05-24 1997-11-04 Svg Lithography Systems, Inc. Illumination system and method employing a deformable mirror and diffractive optical elements
DE19757074A1 (de) * 1997-12-20 1999-06-24 Zeiss Carl Fa Projektionsbelichtungsanlage und Belichtungsverfahren
WO2001071410A2 (fr) * 2000-03-17 2001-09-27 Zograph, Llc Systeme de lentilles pour acuite elevee
DE60228943D1 (de) 2001-04-10 2008-10-30 Harvard College Mikrolinse zur projektionslithographie und ihr herstellungsverfahren
USRE43515E1 (en) 2004-03-09 2012-07-17 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US20050243295A1 (en) * 2004-04-30 2005-11-03 Asml Netherlands B.V. Lithographic apparatus and device manufacturing
LT5497B (lt) 2006-08-25 2008-05-26 Fizikos Institutas Gardelės formavimo būdas ir įrenginys
US8130364B2 (en) 2007-01-04 2012-03-06 Nikon Corporation Projection optical apparatus, exposure method and apparatus, photomask, and device and photomask manufacturing method
JP5190609B2 (ja) * 2008-08-21 2013-04-24 株式会社ブイ・テクノロジー 露光装置及びそれに使用するフォトマスク

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3763372A (en) * 1967-07-13 1973-10-02 Inventors & Investors Inc Zone plate optics monolithically integrated with photoelectric elements
EP0160518A2 (fr) * 1984-05-01 1985-11-06 Xerox Corporation Barreau lumineux
JPS6127548A (ja) * 1984-07-17 1986-02-07 Nec Corp 非接触式露光装置
US4851882A (en) * 1985-12-06 1989-07-25 Canon Kabushiki Kaisha Illumination optical system
US4895790A (en) * 1987-09-21 1990-01-23 Massachusetts Institute Of Technology High-efficiency, multilevel, diffractive optical elements

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3605593A (en) * 1967-07-03 1971-09-20 Tektronix Inc Optical apparatus including a pair of mosaics of optical imaging elements
US3584950A (en) * 1967-11-17 1971-06-15 Xerox Corp Lens strip optical scanning system
US4474459A (en) * 1982-01-20 1984-10-02 Minolta Camera Kabushiki Kaisha Optical projection system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3763372A (en) * 1967-07-13 1973-10-02 Inventors & Investors Inc Zone plate optics monolithically integrated with photoelectric elements
EP0160518A2 (fr) * 1984-05-01 1985-11-06 Xerox Corporation Barreau lumineux
JPS6127548A (ja) * 1984-07-17 1986-02-07 Nec Corp 非接触式露光装置
US4851882A (en) * 1985-12-06 1989-07-25 Canon Kabushiki Kaisha Illumination optical system
US4895790A (en) * 1987-09-21 1990-01-23 Massachusetts Institute Of Technology High-efficiency, multilevel, diffractive optical elements

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
IBM TECHNICAL DISCLOSURE BULLETIN, vol. 34, no. 10A, March 1992 NEW YORK US, pages 158-162, XP 000302260 ANON 'ULTRA-RESOLUTION IMAGE TRANSFER' *
IBM TECHNICAL DISCLOSURE BULLETIN, vol. 9, no. 1, June 1966 NEW YORK US, page 48 H.R. ROTTMANN ET AL 'ZONE LENS ARRAY FOR FABRICATION OF MULTIPLE-IMAGE PATTERNS' *
PATENT ABSTRACTS OF JAPAN vol. 10 no. 180 (P-471) ,24 June 1986 & JP-A-61 027548 (NEC CORP) 7 February 1986, *
SCI. AM. (INT. ED.) (USA), SCIENTIFIC AMERICAN (INTERNATIONAL EDITION), MAY 1992, USA, vol. 266, no. 5, ISSN 0036-8733, pages 50-55, VELDKAMP W B ET AL 'Binary optics' *
See also references of WO9411781A1 *

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KR100310787B1 (ko) 2002-01-09
EP0670052A4 (fr) 1995-10-25
KR950704720A (ko) 1995-11-20
JPH08503560A (ja) 1996-04-16
WO1994011781A1 (fr) 1994-05-26
JP3443627B2 (ja) 2003-09-08
AU6013594A (en) 1994-06-08

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