JP2012146710A - Wafer fixing device and exposure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fix a wafer having a peripheral part warped upward onto a wafer mounting member while ensuring flatness at the peripheral part without causing any damage on the wafer surface, in a wafer fixing device where the wafer is fixed onto the wafer mounting member.SOLUTION: The wafer fixing device 3 has a wafer mounting member 111 for mounting a wafer Wf, and a clamp mechanism 120 for fixing the wafer onto the wafer mounting member while pressing. The wafer is formed so that the circumferential side end face thereof projects outward, and the clamp mechanism 120 has a clamp member 123 which engages with a projection projecting to the outside of the side end face of the wafer and presses the wafer against the wafer mounting member 111.

Description

  The present invention relates to a wafer fixing apparatus and an exposure apparatus, and more particularly to a structure for fixing a wafer (hereinafter also referred to as a semiconductor wafer) used for manufacturing a semiconductor device on a wafer mounting member while maintaining its flatness. It is.

  Conventionally, a wafer fixing apparatus for fixing a semiconductor wafer has been used in various semiconductor processing apparatuses for processing a semiconductor wafer, for example, an etching apparatus, a film forming apparatus, an exposure apparatus, and the like. The structured semiconductor wafer is fixed on a wafer mounting member in the semiconductor processing apparatus.

  FIG. 6 is a diagram for explaining a substrate suction fixing device in a projection exposure apparatus disclosed in Patent Document 1 as a general wafer fixing device, a cross-sectional structure of the substrate suction fixing device (FIG. 6A), and its The structure of the wafer mounting surface (FIG. 6B) is shown.

  A wafer fixing apparatus 200 shown in FIG. 6 is provided in a projection exposure apparatus used for manufacturing a semiconductor element or a liquid crystal display element, and holds and fixes a semiconductor wafer (substrate) that is a workpiece, and corrects the warpage to make a flat surface. It is a substrate suction holding device that uses vacuum suction force to maintain the properties.

  The substrate suction holding apparatus 200 includes a wafer chuck (mounting table) 208 for holding and fixing a semiconductor wafer (substrate). The wafer chuck 208 has a mounting surface 202 for mounting the substrate 201, and a mounting surface. Three through-holes 203a to 203c penetrating from the placement surface 202 to the back side, first edge bank portions 204a to 204c provided on the placement surface along the periphery of these through-holes 203a to 203c, and placement Provided in a region surrounded by the second edge ridge portion 205 formed at the peripheral edge of the surface 202, except for the region surrounded by the first edge ridge portions 204a to 204c. And a convex portion 206 that supports the substrate 201 to be placed.

  Further, the substrate suction holding apparatus 200 further includes three lift pins 209a to 209c, which are arranged so as to pass through the through holes 203a to 203c, respectively, for transferring the wafer 201, and these lift pins 209a to 209c are moved up and down. A vertical movement mechanism 210 for moving the wafer chuck, and a wafer chuck support 212 for supporting the wafer chuck 208; and a substrate 201 to be placed, a placement surface 202, first edge bank portions 204a to 304c, A vacuum piping system 211 for adsorbing and holding the substrate 201 on the mounting surface 202 by reducing the pressure in the space formed by the second edge bank 205 and the convex portion 206 is provided.

  Next, the operation will be described.

  In the substrate suction holding apparatus 200 having such a configuration, a wafer (substrate) 201 as a workpiece is waiting on a lift pin 209 that is in a state of protruding from the mounting surface 202 by an external transfer device (not shown). The vertical movement mechanism 210 lowers the lift pins 209 and delivers the wafer 201 onto the wafer chuck 208. Immediately before or immediately after the wafer 201 comes into contact with the wafer chuck 208, vacuum suction by the vacuum piping system 211 is started, and the wafer 201 is sucked and held on the mounting surface 202 so that the surface thereof becomes flat.

  In this manner, with the wafer 201 held by suction on the wafer chuck 208, the wafer is exposed and transferred by the semiconductor exposure apparatus.

  After the exposure transfer is completed, the wafer is unloaded from the substrate suction holding device by an operation reverse to the loading of the wafer into the substrate suction holding device.

  However, in the general substrate sucking and holding apparatus 200 disclosed in Patent Document 1, when the wafer (substrate) 201 is warped so as to be lifted at the peripheral edge, the wafer is chucked at the peripheral edge. There is a problem that it is difficult to suck and hold 208 so as to be in close contact with the mounting surface 202 of 208.

  In addition, some conventional wafer fixing devices can deal with the above-described warpage at the peripheral edge of the wafer, as disclosed in Patent Document 2.

  FIG. 7 is a diagram for explaining another conventional wafer fixing device disclosed in Patent Document 2. FIGS. 7A and 7B show the operation of fixing a semiconductor wafer by changing the position of a movable part. Show.

  The wafer fixing apparatus shown in FIG. 7 has a platen (wafer mounting member) 20 having a flat upper surface on which the semiconductor wafer 10 is placed, and a component sliding hole 21 formed in the center of the platen 20 in the vertical direction. A fixed chuck 30 that is slidably inserted in the semiconductor wafer 10 and holds the semiconductor wafer 10 by suction; an O-ring 40 having an elastic force that is disposed on the peripheral surface of the mounting region of the semiconductor wafer 10 on the upper surface of the platen 20; A clamp member 50 is provided on the platen 20 so as to be movable up and down, and presses and fixes the peripheral portion of the semiconductor wafer 10 onto the upper surface of the O-ring 40.

  The platen 20 is formed with a suction ductor portion 22 having one end opened on the upper surface of the platen 20 in order to evacuate the sealed space formed by the back surface of the semiconductor wafer 10, the upper surface of the platen 20, and the O-ring 40. Further, a gas injection ductor portion 23 and a gas discharge ductor portion 24 connected to the sealed space for cooling the back surface of the semiconductor wafer 10 are formed.

  Such a wafer fixing apparatus is provided inside the processing chamber of the semiconductor processing apparatus as described above.

  FIG. 8 is a plan view showing a clamp member of the semiconductor wafer fixing apparatus.

  The clamp member 50 is formed of a ring-shaped plate having an inner diameter larger than the diameter of the semiconductor wafer 10, and a large number of claw portions 51 are formed so as to protrude from the inner peripheral surface toward the center. In FIG. 8, reference numeral 11 denotes a chip pattern (planar shape of the chip region) formed on the semiconductor wafer 10.

  Next, the operation will be described.

  When the semiconductor wafer 10 is loaded into a processing chamber of a semiconductor processing apparatus by a wafer loading system (not shown) and held at a position facing the upper surface of the platen 20, the fixed chuck 30 provided on the platen 20 is fixed. Rises to adsorb the semiconductor wafer 10 (see FIG. 7A).

  Thereafter, the lower surface of the peripheral portion of the semiconductor wafer 10 comes into contact with the upper surface of the O-ring 40 by the lowering of the fixed chuck 30, and the semiconductor wafer 10 is placed on the O-ring 40.

  Thereafter, the fixed chuck 30 is further lowered from the semiconductor wafer 10, and the component sliding hole 21 is closed by the cap portion at the upper end of the fixed chuck 30.

  Next, the clamp member 50 is lowered to bring the upper surface of the edge (periphery) of the semiconductor wafer 10 into close contact with the upper surface of the O-ring 40 with a constant pressure, thereby pressing and fixing the semiconductor wafer 10 onto the platen.

  With the semiconductor wafer 10 pressed and fixed on the platen 20 in this way, the semiconductor wafer is processed by the semiconductor processing apparatus.

  By the way, when performing a process on a semiconductor wafer, for example, a process such as plasma etching or sputter deposition, the semiconductor wafer is heated. Therefore, the back side opposite to the front side where the process of the semiconductor wafer 10 is performed is performed. Temperature adjustment is performed so that the temperature of the semiconductor wafer is not excessively increased by cooling.

  Specifically, first, the gas injection ductor 23 and the gas discharge ductor 24 are closed, and then the air is sucked through the suction ductor 22 to form the back surface of the semiconductor wafer 10, the top surface of the platen 20, and the O-ring 40. Make the sealed space vacuum.

Thereafter, the suction ductor portion 22 is closed, the cooling gas is injected from the gas injection ductor portion 23 into the sealed space, and the cooling gas is discharged from the sealed space by the gas discharge ductor portion 24, thereby cooling the semiconductor wafer 10. The semiconductor wafer is cooled by exchanging heat with the working gas. Note that N ₂ gas is mainly used as the heat exchange gas.

Japanese Patent Laid-Open No. 10-233433 Japanese Patent Laid-Open No. 9-181153

  As described above, in the conventional general wafer fixing device (substrate suction fixing device) 200 disclosed in Patent Document 1, when the wafer (substrate) 201 is warped so as to be lifted at the peripheral portion thereof, There is a problem that it is difficult to suck and hold such a wafer so that the peripheral edge thereof is in close contact with the mounting surface 202 of the wafer chuck 208.

  Further, the wafer fixing device disclosed in Patent Document 2 can cope with the warp at the wafer peripheral portion as described above. However, in the wafer fixing device disclosed in Patent Document 2, the peripheral portion of the semiconductor wafer 10 is clamped to the clamper. 50, the wafer is pressed and fixed on the O-ring 40, so that the lower side of the portion inside the O-ring is hollow, and there is a problem that flatness cannot be secured at this portion.

  Also, depending on the state of the O-ring wear, etc., the height of the wafer that is pressed against and fixed to the O-ring changes within the surface of the wafer. The flatness of the wafer surface may be reduced.

  In particular, in an exposure apparatus that exposes a photoresist film or the like used in photolithography technology, flatness of the wafer on the platen (wafer mounting member) is required. In such an exposure apparatus, the wafer is fixed. When the flatness of the wafer surface fixed on the platen by the apparatus is lowered, defective portions P1 and P2 (see FIG. 5C) such as pattern jumps occur in the exposure pattern of the wafer Wf, and a resist as an etching mask is generated. There arises a problem that it becomes impossible to change the planar pattern of the film into a desired pattern.

  Further, since the clamp member comes into contact with the upper surface of the peripheral portion of the wafer, there is a problem that the chip area on the wafer surface is damaged.

  The present invention has been made to solve the above problems, and can fix a semiconductor wafer on a wafer mounting member without damaging the wafer surface while ensuring the flatness of the wafer. It is an object of the present invention to obtain a wafer fixing device and an exposure apparatus using such a wafer fixing device.

  A wafer fixing apparatus according to the present invention is a wafer fixing apparatus having a wafer mounting member for mounting a wafer and a clamp mechanism for pressing and fixing the wafer on the wafer mounting member. The clamp member is formed so that the side end surface of the peripheral edge protrudes outward, and the clamp mechanism engages with a protruding portion protruding outward of the side end surface of the wafer to press the wafer against the wafer mounting member. This achieves the above object.

  According to the present invention, in the wafer fixing apparatus, the wafer has a curved surface shape in a plane including a center of the wafer perpendicular to the surface of the wafer. Preferably there is.

  In the wafer fixing apparatus according to the present invention, the wafer has a polygonal shape in which the surface shape of the protruding portion of the side end face is bent in a plane perpendicular to the wafer surface and including the center of the wafer. It is preferable that

  According to the present invention, in the wafer fixing device, the clamp member is configured such that the surface shape of the engaging portion that engages with the protruding portion of the wafer is curved in a plane that is perpendicular to the surface of the wafer and includes the center of the wafer. It is preferable to have a curved shape.

  In the wafer fixing apparatus according to the present invention, it is preferable that the clamp member is formed of an elastic member so that a uniform pressing force is generated in the entire engaging portion engaged with the protruding portion of the wafer.

  In the wafer fixing apparatus according to the present invention, it is preferable that the clamp mechanism has an elevating member for elevating the clamp member, and the clamp member is detachably attached to the elevating member.

  In the wafer fixing apparatus according to the present invention, it is preferable that the clamp member is attached to the elevating member by a screw member.

  In the wafer fixing apparatus according to the present invention, it is preferable that the surface of the clamp member is coated with an antireflection film that prevents reflection of light.

  In the wafer fixing apparatus according to the present invention, it is preferable that the wafer mounting member has an air suction port formed on a surface thereof for sucking and adsorbing the wafer mounted on the surface.

  In the wafer fixing apparatus according to the present invention, preferably, the wafer mounting member has the air suction port formed in a plurality of concentric annular grooves formed on a surface of the wafer mounting member. .

  An exposure apparatus according to the present invention is an exposure apparatus that exposes a photosensitive film made of a photosensitive material formed on a surface of a wafer, a wafer fixing mechanism that fixes the wafer on a wafer mounting member, A light source for generating exposure light for exposing the photosensitive film formed on the surface; and an optical system for guiding the exposure light generated by the light source onto the photosensitive film. The above-mentioned object is achieved by this.

  Next, the operation will be described.

  In the present invention, in a wafer fixing device for pressing and fixing a wafer onto a wafer mounting member, a clamp that engages with a protruding portion that protrudes outside a side end surface of the wafer and presses the wafer against the wafer mounting member. Since the member is provided, the wafer whose peripheral portion is warped upward can be fixed on the wafer mounting member while ensuring flatness at the peripheral portion and without damaging the surface of the wafer.

  Further, the engaging portion (the peripheral side surface portion of the clamp member) that contacts the wafer etch portion of the clamp member has an arcuate cross-sectional shape like the wafer edge portion (wafer side surface protruding portion). The arc-shaped side edge of the member comes into contact with the arc-shaped side edge of the wafer, so that even if the degree of warping at the wafer edge varies slightly, the wafer edge is securely pressed onto the wafer mounting member. Is possible.

  Further, since the air suction port for adsorbing the wafer is formed on the surface of the wafer mounting member, the flatness of the wafer can be maintained over the entire surface.

  Further, since the air suction port is formed in the annular groove formed concentrically on the surface of the wafer mounting member, it is possible to make the wafer adsorption force by the air flow more uniform in the wafer surface. it can.

  Thereby, a flat and effective portion on the wafer can be maximized, and dust generation from a contact portion between the peripheral edge of the wafer and the wafer mounting member can be suppressed.

  In addition, since the surface of the clamp member is covered with an antireflection film that prevents reflection of exposure light, unnecessary reflection of exposure light on the surface of the clamp member can be prevented.

  As a result, it is possible to improve pattern skipping due to defocusing on the outer periphery of the wafer and realize a good exposure state.

  As described above, according to the present invention, in a wafer fixing apparatus that presses and fixes a wafer onto a wafer mounting member, the wafer is placed on the wafer by engaging with a protruding portion that protrudes outside the side end surface of the wafer. Since it has a clamp member that presses against the mounting member, it can fix the semiconductor wafer on the wafer mounting member while securing the flatness of the wafer without damaging the wafer surface, and such wafer fixing. An exposure apparatus using the apparatus can be obtained.

FIG. 1 is a diagram conceptually illustrating an exposure apparatus according to Embodiment 1 of the present invention. FIG. 2 is a view for explaining the wafer fixing device used in the exposure apparatus according to Embodiment 1 of the present invention, and FIG. 2 (a) is a cross-sectional view schematically showing the overall configuration of the wafer fixing device. FIG. 2B is a plan view showing a wafer mounting member constituting the wafer fixing device. FIG. 3 is a view for explaining the planar shape of the clamp member of the wafer fixing apparatus according to the first embodiment of the present invention. FIG. 3A shows a planar ring-shaped clamp member that presses the wafer by the entire inner peripheral edge. FIG. 3B shows a clamp member that presses the wafer at several locations on the inner periphery. FIG. 4 is a view for explaining the wafer fixing apparatus according to Embodiment 1 of the present invention. FIG. 4A shows a state in which the clamp member clamps a wafer having a semicircular sectional shape at the side end. FIG. 4B shows a state in which the clamp member clamps a wafer whose side end portion has a polygonal cross-sectional shape. FIG. 5 is a diagram for explaining the function and effect of the wafer fixing apparatus according to the first embodiment of the present invention. When clamping a wafer without warping at the side edge (FIG. 5A), FIG. When a certain wafer is clamped (FIG. 5B), the resist film has a poor exposure pattern (FIG. 5C), and the resist film is well exposed (FIG. 5D). FIG. 6 is a diagram for explaining a substrate suction fixing device disclosed in Patent Document 1 as a conventional wafer fixing device. FIG. 6 shows a cross-sectional structure of the substrate suction fixing device (FIG. 6A) and its wafer mounting surface. The structure (FIG. 6B) is shown. FIG. 7 is a diagram for explaining another conventional wafer fixing device disclosed in Patent Document 2. FIGS. 7A and 7B show the operation of fixing the semiconductor wafer according to the position of the movable portion. Shown by change. FIG. 8 is a plan view showing a clamp member of a conventional semiconductor wafer fixing apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a view for conceptually explaining an exposure apparatus according to Embodiment 1 of the present invention.

  An exposure apparatus 1 shown in FIG. 1 is an exposure apparatus that exposes a photosensitive film made of a photosensitive material formed on the surface of a wafer Wf, for example, a resist film (not shown). The exposure apparatus 1 includes a wafer fixing mechanism 3 that fixes the wafer on a wafer mounting member, a light source 11 that generates exposure light for exposing a photosensitive film formed on the surface of the wafer, and a light source 11 that generates the exposure light. And an optical system 2 that guides the exposed exposure light onto the photosensitive film. FIG. 1 conceptually shows a stage portion 100 including a movable portion and a fixed portion in the wafer fixing mechanism 3.

  Here, the optical system 2 includes a diaphragm member 12, a first condenser lens 13 that condenses the light that has passed through the diaphragm member 12 on the reticle R, and the wafer fixing mechanism 3 that transmits the light that has passed through the reticle R. And a second condenser lens 14 for condensing light on the wafer Wf fixed thereon.

  FIG. 2 is a view for explaining a wafer fixing device as the wafer fixing mechanism, FIG. 2 (a) is a cross-sectional view schematically showing the wafer fixing device, and FIG. 2 (b) is the wafer fixing device. It is a top view which shows the wafer mounting member which comprises an apparatus.

  The wafer fixing device 3 clamps and presses the wafer, and includes a wafer mounting member 111 for mounting the wafer Wf1, and a clamp mechanism 120 for pressing and fixing the wafer on the wafer mounting member 111. have.

  Here, as shown in FIG. 4A, the wafer Wf is formed such that the side end surface Sw of the peripheral edge protrudes outward. In other words, the wafer Wf has a surface shape of the protruding portion Cv on the side end surface thereof that is curved in a plane perpendicular to the surface of the wafer and including the center of the wafer.

  The shape of the protruding portion on the side surface of the wafer is not limited to a curved shape as shown in FIG. For example, in the wafer Wfa shown in FIG. 4B, the surface shape of the protruding portion Cva of the side end surface Swa is a polygonal shape that is bent in a plane that is perpendicular to the surface of the wafer and includes the center of the wafer. The shape of the side end surface of such a wafer may be a polygonal shape as shown in FIG.

  The clamp mechanism 120 has a clamp member 123 that engages with a protruding portion Cv protruding outside the side end surface of the wafer Wf and presses the wafer against the wafer mounting member.

  The clamp member 123 can be made of, for example, an insulating member such as ceramic. However, the elastic member is used to generate a uniform pressing force on the entire engaging portion 123a that engages with the protruding portion Cv1 of the wafer. It may be configured.

  The clamp mechanism 120 has an elevating member 122 that elevates and lowers the clamp member 123, and the clamp member 123 is attached to the elevating member 122 by a screw member 122a so as to be detachable. However, the clamp member 123 may be fixed to the elevating member 122 by welding or the like. The elevating member 122 is supported by an elevating drive device 121 attached to the wafer mounting member 111 so that the elevating member 122 can be moved up and down by this device.

  The clamp member 123 preferably has a structure in which the surface thereof is covered with an antireflection film that prevents reflection of exposure light.

  Further, the wafer mounting member 111 has a planar circular shape shown in FIG. 2B, and the lifting drive device 121 is spaced at an angle of 120 degrees on the outer peripheral side surface of the wafer mounting member 111. It is attached with a gap.

  However, the interval between the adjacent lifting members 122 is set to be larger than the diameter of the wafer so that the wafer can be carried onto the wafer mounting member 111 between the adjacent lifting members 122.

  The structure for loading the wafer onto the wafer mounting member 111 from the outside of the wafer fixing device is limited to a structure that allows the wafer to be loaded into the wafer mounting member 111 through the space between the adjacent lifting members 122. is not. For example, the ring-shaped clamp member 123 or 133 (see FIG. 3A or 3B) has a structure that can be divided into two at the central portion, and the wafer is loaded onto the wafer mounting member 111 from the outside of the wafer fixing apparatus. At this time, the ring-shaped clamp member may be divided into two to form a path for carrying the wafer onto the wafer mounting member 111.

  An air suction port 112a is formed on the surface of the wafer mounting member 111 for sucking and adsorbing the wafer mounted on the surface. As shown in FIG. 2A, the air suction port 112a is preferably formed on the bottom surface portion of the suction groove 112 formed in a concentric manner on the surface of the wafer mounting member 111.

  FIG. 3 shows the planar shape of the clamp member 123. The clamp member 123 has a ring shape as shown in FIG. 3A, and its inner diameter is larger than the diameter of the wafer. As shown in FIG. 4A, when the center of the wafer is aligned with the center of the ring-shaped clamp member, the protruding portion Cv on the side surface of the wafer Wf is at the inner peripheral side edge of the clamp member 123, as shown in FIG. A certain engaging portion 123a is in contact with the entire circumference excluding the orientation flat portion of the wafer.

  Here, the wafer mounting member 111 is formed with a plurality of air suction paths 113 connected to the air suction port 112a, and the wafer is moved up and down at the center when the wafer is delivered. An insertion hole 114 for arranging the elevating rod 104c is formed, and the lower end of the elevating rod 104c is attached to an elevating plate 104b that elevates and lowers by a drive mechanism (not shown).

  Further, the wafer mounting member 111 is supported on the first movable table 104 at three points by three support rods 104a. That is, the wafer mounting member 111 has a planar circular shape as shown in FIG. 2B, and the three support rods 104a are located in the vicinity of the outer peripheral edge on the back side of the wafer mounting member 111. Are arranged at an angle of 120 degrees.

  Therefore, by independently adjusting the heights of the three support rods 104a, the angle of the wafer surface with respect to the optical axis of the exposure light from the light source 11 can be adjusted.

  Further, the first movable table 104 is arranged on the second movable table 103 with respect to the second movable table 103 in the X direction (the left-right direction of the paper surface of FIG. 2) and the Y direction (the paper surface of FIG. 2). The second movable base 103 is supported on the third movable base 102 so as to be vertically movable by a lift pin 102a. By moving the second movable table 103 up and down, the position of the wafer can be adjusted so that the focal position of the exposure light is on the wafer surface.

  The third movable table 102 is held so as to be movable in a horizontal plane with respect to the fixing member 101 of the main body of the exposure apparatus 1, and the wafer fixing device 120 is sequentially exposed to the chip area on the wafer by exposure light from the light source. It has a function as a stepper to be moved.

  Further, the clamp member 133 shown in FIG. 3B has a planar shape different from the planar shape of the clamp member 123 shown in FIG.

  In other words, the clamp member 133 has a ring-shaped shape, and a main body portion 133a having an inner diameter slightly larger than the diameter of the wafer, and a clamp piece 133b extending from the ring-shaped main body portion 133a to the inner peripheral side. And has a structure in which the wafer Wf is pressed and fixed onto the wafer mounting member by the tip of the clamp piece.

  Next, the operation will be described.

  In the exposure apparatus 1 having such a configuration, when a wafer Wf on which a photosensitive material film (resist film) is formed is loaded, the wafer Wf is fixed by a wafer fixing apparatus 3 as a wafer fixing mechanism.

  That is, as shown in FIG. 2A, the wafer (see FIG. 1) is placed on the lifting rod 104c with the lifting rod 104c protruding from the surface of the wafer mounting member 111, and the lifting rod 104c. As the elevating plate 104b is lowered, the wafer is placed on the wafer placing member 111 of the wafer fixing device 3. At this time, the wafer Wf is adsorbed and fixed to the surface of the wafer mounting member 111 by the air flow sucked into the air suction port 112 a provided on the surface of the wafer mounting member 111.

  Thereafter, when the elevating drive device 121 lowers the elevating member 122, the engagement portion (inner peripheral side edge portion) 123a of the clamp member 123 attached to the elevating member 122 becomes the wafer Wf as shown in FIG. The clamp member 123 presses and fixes the wafer Wf to the wafer mounting member 111 with a predetermined pressing force.

  At this time, when the clamp member 123 is formed of an elastic member, the clamp member 123 presses the peripheral edge of the wafer with a uniform pressing force over the entire periphery.

  As a result, as shown in FIG. 5B, even when the wafer is warped at the peripheral edge, as shown in FIG. In addition, the peripheral edge of the wafer is closely fixed to the surface of the wafer mounting member.

  Thus, with the wafer fixed by the wafer fixing device 3, the height of the support rod 104a is such that the wafer surface is at a predetermined angle, for example, perpendicular to the optical axis of the exposure light from the optical system. Adjusted.

  Further, the movement of the first movable table 104 in the horizontal plane aligns the exposure pattern transmitted through the reticle R with respect to each chip region, and the second movable table 103 moves up and down to focus the exposure light. The height of the wafer mounting member is adjusted so that the position is on the wafer surface.

  Then, after the angle and position of the wafer with respect to the optical system of the exposure light are adjusted in this way, the resist film is exposed for each chip region Ch of the wafer Wf.

  At this time, the third movable stage 102 functions as a stepper that moves the wafer fixing device 120 so that the chip regions on the wafer are sequentially exposed by the exposure light from the light source.

  When the exposure process for the chip area of the wafer Wf is completed in this way, the lifting drive device 121 raises the lifting member 122, thereby engaging the engagement portion (inner peripheral side edge) of the clamp member 123 attached to the lifting member 122. Part) 123a is separated from the protruding portion Cv on the side surface of the wafer Wf, and the pressing and fixing of the wafer Wf by the clamp member 123 is released. Further, the adsorption operation by the air flow to the air suction port of the wafer is stopped, and the adsorption of the wafer to the wafer mounting member 111 is released. Further, when the lifting rod 104c is lifted, the wafer is lifted from the wafer mounting surface by the lifting rod 104c. In this state, the wafer is removed from the lifting rod 104c by the transfer arm of the transfer device (not shown), and next It is transferred to a processing chamber by a semiconductor processing apparatus in the process, for example, an etching apparatus.

  The exposure apparatus 1 according to the first embodiment configured as described above includes the wafer fixing device 3 that presses and fixes the wafer Wf onto the wafer mounting member 111, and the wafer fixing device 3 is disposed outside the side end surface of the wafer. Since the structure has the clamp member 123 that engages with the projecting protruding portion Cv and presses the wafer Wf against the wafer mounting member 111, the wafer Wf whose peripheral portion is warped upward is flattened at the peripheral portion. It can be fixed on the wafer mounting member while ensuring the property and without damaging the surface of the wafer.

  Furthermore, the engaging portion (peripheral side surface portion of the clamp member) 123a that contacts the wafer etch portion of the clamp member 123 has an arcuate cross-sectional shape in the same manner as the edge portion (side surface protruding portion of the wafer) Cv. Therefore, the arc-shaped side end portion of the clamp member comes into contact with the arc-shaped side edge portion of the wafer, and the wafer edge portion Cv is surely placed on the wafer mounting member 111 even if the degree of warping at the wafer edge portion varies somewhat. It becomes possible to press and fix.

  In this embodiment, since the air suction port 112a for adsorbing the wafer is formed on the surface of the wafer mounting member 111, the flatness of the wafer can be maintained over the entire surface.

  Further, since the air suction port 112a is formed in a plurality of suction grooves 112 formed concentrically on the surface of the wafer mounting member 111, the wafer suction force by the air flow is more uniformly in the plane of the wafer. can do.

  Thereby, a flat and effective portion on the wafer can be maximized, and dust generation from a contact portion between the peripheral edge of the wafer and the wafer mounting member can be suppressed.

  In addition, since the surface of the clamp member is covered with an antireflection film that prevents reflection of exposure light, unnecessary reflection of exposure light on the surface of the clamp member can be prevented.

  As a result, it is possible to improve the pattern skips P1 and P2 (FIG. 5C) due to defocusing of the outer peripheral portion of the wafer and realize a good exposure state (FIG. 5D).

  As mentioned above, although this invention has been illustrated using preferable embodiment of this invention, this invention should not be limited and limited to this embodiment. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge from the description of specific preferred embodiments of the present invention. It is understood that the patent documents cited in the present specification should be incorporated by reference into the present specification in the same manner as the content itself is specifically described in the present specification.

  The present invention relates to a wafer fixing apparatus and a wafer fixing apparatus capable of fixing a semiconductor wafer onto a wafer mounting member without damaging the wafer surface while ensuring the flatness of the wafer in the field of a wafer fixing apparatus and an exposure apparatus. An exposure apparatus using a simple wafer fixing apparatus can be provided.

DESCRIPTION OF SYMBOLS 1 Exposure apparatus 2 Optical system 3 Wafer fixing device (wafer fixing mechanism)
DESCRIPTION OF SYMBOLS 11 Light source 12 Diaphragm member 13 1st condensing lens 14 2nd condensing lens 102 3rd movable stand 103 2nd movable stand 104 1st movable stand 104a Support rod 104b Lifting plate 104c Lifting rod 111 Wafer mounting Member 112 Suction groove 112a Air inlet 114 Parts sliding hole 120 Clamp mechanism 121 Lifting drive device 122 Lifting member 122a Screw member 123, 133 Clamp member 133a Clamp member main body 133b Clamp piece Cv, Cva Protruding portion R Reticle Sw, Swa Wafer Side end face Wf, Wfa Wafer

Claims (11)

A wafer fixing device having a wafer mounting member for mounting a wafer, and a clamp mechanism for pressing and fixing the wafer on the wafer mounting member,
The wafer is formed such that the side end surface of the periphery projects outward.
The wafer fixing apparatus, wherein the clamp mechanism includes a clamp member that engages with a protruding portion that protrudes outward from a side end surface of the wafer and presses the wafer against the wafer mounting member. The wafer fixing apparatus according to claim 1,
The wafer fixing apparatus, wherein the wafer has a surface shape of a protruding portion on a side end surface thereof curved in a plane perpendicular to the surface of the wafer and including a center of the wafer. The wafer fixing apparatus according to claim 1,
The wafer fixing apparatus, wherein the wafer has a surface shape of a protruding portion on a side end surface thereof, which is a polygonal shape bent in a plane perpendicular to the surface of the wafer and including the center of the wafer. In the wafer fixing device according to claim 2 or 3,
The clamp member is a wafer in which the surface shape of the engaging portion that engages with the protruding portion of the wafer is a curved shape that is curved in a plane that is perpendicular to the surface of the wafer and includes the center of the wafer. Fixing device. The wafer fixing apparatus according to claim 1,
The wafer fixing apparatus, wherein the clamp member is constituted by an elastic member so that a uniform pressing force is generated in the entire engaging portion that engages with the protruding portion of the wafer. The wafer fixing apparatus according to claim 1,
The clamping mechanism is
An elevating member for elevating the clamp member;
The wafer fixing device, wherein the clamp member is detachably attached to the elevating member. The wafer fixing apparatus according to claim 6, wherein
The wafer fixing apparatus, wherein the clamp member is attached to the elevating member by a screw member. The wafer fixing apparatus according to claim 1,
The wafer fixing apparatus, wherein the clamp member has a surface coated with an antireflection film that prevents light reflection. The wafer fixing apparatus according to claim 1,
The wafer mounting apparatus, wherein the wafer mounting member is formed with an air suction port for sucking and adsorbing the wafer mounted on the surface of the wafer mounting member. The wafer fixing apparatus according to claim 9, wherein
The wafer mounting apparatus is a wafer fixing apparatus in which the air suction port is formed in an annular groove formed in a plurality of concentric shapes on the surface of the wafer mounting member. An exposure apparatus that exposes a photosensitive film made of a photosensitive material formed on a surface of a wafer,
A wafer fixing mechanism for fixing the wafer on the wafer mounting member;
A light source for generating exposure light for exposing a photosensitive film formed on the surface of the wafer;
An optical system that guides the exposure light generated by the light source onto the photosensitive film,
The exposure apparatus according to claim 1, wherein the wafer fixing mechanism is a wafer fixing apparatus.

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