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
  • G03F7/707—Chucks, e.g. chucking or un-chucking operations or structural details
• • 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
  • G03F7/707—Chucks, e.g. chucking or un-chucking operations or structural details
  • G03F7/70708—Chucks, e.g. chucking or un-chucking operations or structural details being electrostatic; Electrostatically deformable vacuum chucks
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
  • H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
  • H01L21/6831—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping using electrostatic chucks

Definitions

• the invention relates to a device for holding a substrate in a containment system, in which the substrate rests on a movable table in the coordinates X, Y and between the table surface and the substrate dimensionally encoding means for adjusting the distance and aligning the substrate relative to a viewing optics are from which a corpuscular radiation is directed at a right angle, corresponding to the coordinate Z, onto the substrate surface
• Holding devices for holding substrates, in particular masks and wafers, during exposure in optical, including electron-optical, inspection systems are known in the prior art in various designs.
• the holding systems are arranged on a table which can be moved in two coordinates XN and have one Support plane for the substrate, on which the substrate is placed and on which it is held before the exposure process begins, while the table is shifted step by step in the X and / or Y direction and brought into the desired viewing positions one after the other high-level support surfaces, partly also formed by several point-shaped support elements.
• the basic bodies, support plates, etc., on which support elements are arranged or support surfaces are formed, are generally mechanically fixed to the coordinate Z by means of dimensional adjustment for aligning the substrate Table connected
• the coordinate Z corresponds to the direction of irradiation of the exposure beam path directed at right angles to the substrate surface
• the positioning accuracy of the substrate surface, the alignment of the support plane, the flatness of a support surface and last but not least the dimensional stability of all parts and assemblies of the holding system are of essential importance for the goodness and delicacy of the structure aimed for during exposure, the more the efforts of the Microelectronics industry are aimed at further reducing the structural width
• sapphire is provided as the supporting material for the substrate.Not all of the 8-inch supporting surface has been covered with sapphire, but only a few 2-inch-large sapphire discs have been arranged over an intermediate layer of niobium, the surfaces of which form the supporting surface for the substrate.
• the disadvantage here is the complex manufacturing process for the multi-part supporting surface, which causes high costs in addition to the expensive sapphire material
• a further receiving device for substrates is described in US Pat. No. 5,600,530, in which an electrostatic chuck arrangement is again provided.
• aluminum oxide is used here as the material for the insulating layer.
• a method is specified by which the aluminum oxide layer is thinned back to position the substrate.
• the use of aluminum oxide disadvantageously leads to problems that are due to its unfavorable coefficient of thermal expansion.Therefore, the use of aluminum oxide inevitably requires measures that compensate for this disadvantage and a change in position and / or shape of the substrate that goes beyond an acceptable level Preventing fluctuations in temperature The solution to this problem is not apparent from the document mentioned
• the holding systems are always designed only for substrates of a predetermined size.
• the known holding systems are not or only partially suitable for use for the exposure of individual substrates or of series of substrates of different sizes, for example only under the condition of a very high assembly and adjustment effort
• the object of the invention is to further develop a holding device of the type described above in such a way that support elements for the substrate can be exchanged for one another quickly and easily, and nevertheless high positioning accuracy is achieved
• this object is achieved in that two support plates aligned parallel to the plane X, Y are provided on the table in the direction of the viewing optics and at different distances from the table surface, of which a first support plate is connected directly to the table and the second support plate via at least a holding device, the holding function of which can be switched on and off, is connected to the first support plate, a support plane for the substrate being formed on the side of the second support plate facing the viewing optics.
• the first support plate is connected to the table via vibration-damping elements and that the switchable holding devices which hold the second support plate are provided on the first, at the same time are designed as spacers, by means of which the two support plates are held at a predetermined distance in the direction of the coordinate Z from one another and between the two support plates there is a space into which, for example, a lifting device coupled to a robot arm is inserted and with it the second support plate can be removed or exchanged for a second support plate with a different size of the support plane
• At least the second support plate, on which the support plane for the substrate is formed is designed with regard to its material properties, its dimensions and its shape so that forces are caused, for example, by material expansion of temperature changes or in mechanical impacts and which are of such a size that they could cause deformation of the substrate beyond an allowable amount, are not transferred to the substrate.
• a so hard material is provided that a plastic deformation due to the application of force is not permitted
• connection of the first support plate to the table can be made by spacing elements which, on the one hand, are mechanically fixed to the table surface are connected and, on the other hand, are coupled to the second support plate via elastic intermediate layers, which consist, for example, of a fluorine elastomer.
• a particularly preferred embodiment of the invention provides that electrostatic chuck arrangements are provided as holding devices between the two support plates. These each consist of a base body made of electrically non-conductive material, on which an electrically conductive layer, for example made of nickel or chromium, and above which in turn an insulating layer is arranged. With regard to its areal extent, the electrically conductive layer can advantageously be divided into individual segments, each segment being connectable separately to an electrical potential.
• the surfaces of the insulating layer facing the exposure optics are designed as contact surfaces for the second support plate.
• these chuck arrangements also have the function of forming a reference plane for aligning the second support plate and thus the substrate, which is arranged on the second support plate as shown.
• the support plane for the substrate is formed from three balls, which are held, for example, by cages on the second support plate or which are glued to the second support plate.
• the balls can be arranged radially symmetrically, forming a three-point support for the substrate, on a pitch circle.
• one or more electrostatic chuck arrangements are arranged on the second support plate (in addition to the chuck arrangements that serve to hold the second support plate), on which a support plane for the substrate is formed and whose task is to hold the substrate electrostatically on the second support plate.
• Base body of this chuck arrangement for example by wringing or gluing, attached to the second support plate.
• the electrically conductive layer is provided with contacts.
• an electrical potential is applied to the respective electrically conductive layer of the one concerned Chuck arrangement and on the other hand placed on the assembly placed on the insulating layer (the second support plate) or on the placed part (substrate)
• This material enables a structure that is extremely insensitive to temperature fluctuations. Temperature influences within the protective arrangement can hardly be avoided during the exposure process, they can result from heat conduction and / or heat radiation within the system, but can also be entered through the exposure of the substrate However, the negative consequences of disturbing temperature influences can be reduced to such an extent that the effort for temperature stabilization within the guard arrangement or in the vicinity of the substrate can be reduced to a minimum
• the glass ceramic used can be processed effectively and with maximum dimensional accuracy using conventional optical processing technologies.This applies in particular to the production of flat surfaces, but also compliance with parallelism and angles.This enables manufacturing tolerances in the micrometer range and in the range of Arc seconds must be observed Due to the hardness of the glass ceramic, plastic deformations on the flat surfaces are excluded. As already described above, this prevents uncontrolled substrate deformation
• coatings can be applied to the parts made of glass ceramic using conventional technologies.
• Such coatings can be mirror layers, for example for interferometer mirrors, or also electrically conductive layers.
• the latter serve to apply an electrical potential.
• the latter serves to avoid electrostatic charges at undesired locations, which can otherwise occur, for example, when electrically charged particles hit insulating surfaces during the exposure.
• the electrical potential for generating the electrostatic chuck can also be applied to this layer. Holding forces are placed between the first and second support plate
• the glass ceramic used is magnet-free, this ensures that the observation beam path cannot be influenced by magnetic fields, which can have their origin in components made of metallic materials or materials with magnetic particles
• An electrical potential of up to 5000 V is provided to generate the electrostatic forces.
• the potential can be switched, so that the holding forces can be switched on and off as required
• Chuck arrangements are attached, which together form a support surface for the second support plate.
• the chuck arrangements can be positioned, for example, radially symmetrically to one another on a pitch circle.Their dimensions in the direction of the coordinate Z and their distances from one another in the coordinates XN are such that between the chuck arrangements and between the first and the second support plate there is sufficient space to insert a lifting tool connected to a robot arm and to grip under it with the second support plate, lift it off the support surface, remove it from the device and replace it with a support plate which is designed to accommodate a substrate of a different size
• the described holding device for the substrate can also be equipped with a metrology system which serves to determine and monitor the position of the substrate in the coordinates XN during the exposure and in which two orthogonally aligned mirrors are provided which serve as a reference for an interferometric measuring arrangement
• the two mirrors can either be placed directly on the first support plate or placed on intermediate bars that are connected to the first support plate. In the latter case, the intermediate bars serve as spacers for adjusting the positions of the mirrors in the direction of the coordinate Z.
• Basic bodies of the mirrors are made by wringing or gluing. It is also advantageous if the mirrors are made from the same glass ceramic as mentioned above, so that there is a uniform expansion behavior of the relevant parts or assemblies under the influence of temperature.
• coatings can be applied to the base bodies of the mirrors high reflectivity, for example made of aluminum with an oxide protective layer
• FIG. 1 shows a top view from FIG. 1
• FIG. 3 shows the basic structure of the arrangement according to the invention with an electrostatic chuck arrangement for receiving the substrate
• FIG. 4 shows a top view from FIG. 3
• FIG. 5 shows the basic structure of an electrostatic chuck arrangement
• the viewing optic 2 is, for example, an electron-optical exposure system, from which the exposure radiation is directed at a right angle, following the coordinate Z, onto the table
• a first support plate 3 is initially arranged on the table 1 in the direction of the viewing optics 2.
• the surface of the supporting plate 3, which faces the viewing optics 2, is provided as a first reference plane 4.
• this area is designed to be raised and to that of the coordinates XN spanned plane aligned exactly parallel
• the support plate 3 is mechanically connected to the table 1 by means of fastening elements 6, which can be pressed or screwed to the table 1, for example on the table surface 5.
• the connection between the fastening elements 6 and the support plate 3 is designed such that corresponding annular widenings 7 , 8 on the fastening elements 6 as well as on the support plate 3 are opposed to one another.
• damping elements 9 made of a fluorine elastomer are arranged, the task of which is the transmission of vibrations, impacts or / or deformations to reduce or prevent from the table 1 on the support plate 3
• three electrostatic chuck arrangements 11 are arranged, which have a circular cross-sectional area.
• the surfaces of the three chuck arrangements 11 facing the observation optics 2 together form a second reference plane 12 and at the same time a support plane for a second supporting plate 16
• each of the chuck arrangements 11 has a basic body
• the electrically conductive layer 14 made of chrome or nickel and an insulating layer 15 is applied over it.
• the electrically conductive layer 14 can be applied in the form of several segments which are electrically separated from one another, so that different electrical potentials can be applied to the individual segments
• the basic bodies 13 and the insulating layers 15 of the chuck arrangements 11 are made from a glass ceramic having the same properties, as a result of which differences in expansion behavior are minimized are or the accuracy of the reference plane 12 is retained even with the influence of temperature.
• the "ZERODUR" glass ceramic already described is advantageously provided here.
• Support elements for the substrate 18 arranged.
• the balls 17 are held in their position by cages 19 which are glued to the support plate 16 (cf. FIG. 2).
• the support plate 16 and the balls 17 are advantageously made of the same glass ceramic as the base body 13 and the insulating layers 15.
• the components which serve to measure the coordinate Z above the first reference plane 4 are thus made of the same material.
• the support plate 16 is provided with a layer 10 made of an electrically conductive material. If an electrical potential of 3000 V, for example, is applied to the layer 10 on the one hand and to the conductive layers 14 of the chuck arrangements 11 on the other hand, electrostatic forces are generated by which the support plate 16 is held in the position shown in FIG. 1 on the support plate 3 .
• electrical connections 20 are passed through the base body 13 of the chuck arrangements 11.
• the potential can be switched on or off by means of a switch (not shown), so that after the voltage has been disconnected, the electrostatic forces are eliminated and the support plate 16 together with the support elements for the substrate 18 can be removed from the chuck arrangements 11 so that the support plates 16 can be exchanged at any time and support plates for substrates of different sizes can be exchanged for one another in a simple manner.
• two mirrors 21 and 22 are also provided on the support plate 3, each of which is set at a distance from the reference plane 12 via an intermediate bar 24 or 25.
• the mirrors 21 and 22 serve as reference mirrors for a laser measuring system, which is not described here in each case.
• One of the mirrors 21, 22 is assigned to one of the coordinates XN, and consequently they are orthogonal aligned to each other They consist of a basic body made of glass ceramic, which is provided in the measuring direction with a highly reflective layer, for example made of aluminum with an oxide layer
• the laser measuring system it is possible to determine the position of the table 1 and thus the position of the substrate 18 in the coordinates XN during the exposure and to check and, if necessary, correct it after each shift of the table 1 into the next exposure position
• FIG. 2 shows a top view of the arrangement according to FIG. 1.
• the orthogonal alignment of the two mirrors 21 and 22 can be seen here as well as the positions of the chuck arrangements 11 and the balls 17 on which the substrate 18 is placed.
• the structure is provided above the table 1 in the direction of the viewing optics 2 up to the support plate 16, as in the previously explained example.
• the chuck arrangement 23 is constructed in the same way as the chuck arrangements 11 according to FIG. 5. That is, an electrically conductive layer 14 is applied to a base body 13 and an insulating layer 15 is applied above it. The insulating layer 15 is raised so that the substrate 18 can be placed on it Is held there in the correct form
• the electrostatic holding forces become analog here generated by applying an electrical potential to the electrically conductive layer 14 on the one hand and to the substrate 18 on the other hand. This potential can also be switched, so that the substrate can be held or released from the chuck arrangement 23 with the switching on or off.
• the electrostatic attraction is dependent on the size of the voltage, the area size of the chuck arrangement 23 and the thickness of the insulating layer 15.
• the outer surface or contact surface of the insulating layer 15 is designed with a surface profile of a depth in the ⁇ m range, so that the substrate can be easily removed from the insulating layer 15 after potential isolation.
• chuck arrangement 23 is circular and its diameter is adapted approximately to the dimensions of the substrate 18.
• the positioning of the chuck arrangements 11 by which the support plate 16 is held can also be seen here.
• the components made of glass ceramic are provided with an electrically conductive coating on their surface, at least on the surface sections which have no function with regard to a material measure in the direction of the coordinate Z.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Condensed Matter Physics & Semiconductors (AREA)
• Manufacturing & Machinery (AREA)
• Computer Hardware Design (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Power Engineering (AREA)
• Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
• Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)
• Container, Conveyance, Adherence, Positioning, Of Wafer (AREA)
• Electron Beam Exposure (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

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Cited By (5)

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Citations (2)

Family Cites Families (21)

• 1998
  • 1998-11-20 DE DE19853588A patent/DE19853588B4/de not_active Expired - Fee Related
• 1999
  • 1999-11-16 US US09/600,630 patent/US6426860B1/en not_active Expired - Lifetime
  • 1999-11-16 JP JP2000584509A patent/JP4499293B2/ja not_active Expired - Fee Related
  • 1999-11-16 DE DE59912677T patent/DE59912677D1/de not_active Expired - Lifetime
  • 1999-11-16 WO PCT/DE1999/003638 patent/WO2000031774A2/de active IP Right Grant
  • 1999-11-16 EP EP99963248A patent/EP1050070B1/de not_active Expired - Lifetime
  • 1999-11-17 TW TW088120041A patent/TW452674B/zh not_active IP Right Cessation

Patent Citations (2)

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