JP4014031B2 - Substrate processing apparatus and substrate processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize improvement in throughput and reduction in size of an apparatus by performing peripheral exposure of a substrate to be processed on which a resist film is formed and linear exposure of an identification mark region. <P>SOLUTION: The substrate processing apparatus comprises a chuck 80 for holding a wafer W with the surface thereof located at a upper side, a motor 81 for rotating the chuck 80, a moving means 90 for linearly moving the wafer W in the horizontal direction, and an exposing means 60 for irradiating the surface of the wafer W with light. The exposing means 60 is provided with a light source 61, a first mask 67 having a rectangular slit for adjusting the exposing area from the light source 61 and guiding the light to a region in the peripheral part of the wafer W, a second mask 69 having a circular slit for adjusting the exposing area from the light source 61 and guiding the light to the region of alignment mark of the wafer W, and a mask change-over moving mechanism 72 for realizing change-over movement of the circular slit of the second mask 69 to the location just under the light source 61 or to the standby position. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate processing apparatus and a substrate processing method, for example, a substrate processing apparatus and a substrate processing for removing unnecessary portions of a resist film formed on a substrate to be processed such as a semiconductor wafer having a linear identification mark. It is about the method.
[0002]
[Prior art]
In general, in a manufacturing process of a semiconductor wafer or the like, a photolithography technique is used to form a resist pattern on a surface of a substrate to be processed (substrate to be processed) such as a semiconductor wafer or an LCD substrate. This photolithography technology includes a resist coating process for applying a resist solution to the surface of a substrate to be processed, an exposure processing process for exposing a circuit pattern to the formed resist film, and a development for supplying a developer to the substrate after the exposure process. And processing steps. In this case, in the resist coating process, a resist solution is supplied (dropped and discharged) to the surface of the substrate to be rotated, and a resist film is formed on the surface of the substrate to be processed by centrifugal force. Therefore, the film thickness of the resist film in the peripheral part of the substrate to be processed is increased, and the film thickness uniformity on the surface of the substrate to be processed is impaired. In addition, there is a possibility that the transfer of the substrate to be processed may be hindered, and the surplus resist film in the peripheral portion may be peeled off during the transfer or processing of the substrate to be processed to generate particles. Further, there is a problem that the accuracy of flattening the coating film is lowered in the coating process in which a plurality of coating processes are performed. In order to solve these problems, conventionally, the peripheral portion of the substrate to be processed after resist coating is exposed, and the excess resist film on the peripheral portion of the surface of the substrate to be processed is removed by development processing. In this case, light from the light source is irradiated to a predetermined area in the peripheral portion of the substrate to be processed through a rectangular slit that adjusts the exposure area to make the light quantity constant, for example, a rectangular slit of 4 mm × 5 mm or 4 mm × 10 mm. At the same time, the substrate to be processed is rotated to expose the peripheral portion of the substrate to be processed after the resist application.
[0003]
By the way, in the manufacturing process of the semiconductor wafer or the like, an alignment mark is formed on the surface of the substrate to be processed so that the relative position accuracy of the next process design pattern with respect to the existing pattern on the substrate to be processed and the type or use of the substrate to be processed can be identified. Etc. are given an identification mark. This identification mark is generally provided in a straight line in a region (place) that is closer to the center of the substrate to be processed than a region that is peripherally exposed at the peripheral portion of the surface of the substrate to be processed and that does not cover the chip of the circuit pattern. . However, in the above-described resist coating process, the resist liquid is also coated on the identification mark, and there is a possibility that the reading of the identification mark may be hindered. For this reason, conventionally, a substrate to be processed on which a resist film is formed is transported to an exposure apparatus, and an exposure process is performed on a region provided with an identification mark, followed by a development process.
[0004]
[Problems to be solved by the invention]
However, when the area of the identification mark is formed in the exposure apparatus, the number of steps for transporting the substrate to be processed is increased, and a long time is required for the processing. Thus, there is a problem that the throughput is reduced and the apparatus is enlarged.
[0005]
As a method of solving this problem, a method of exposing the area of the identification mark in the peripheral exposure apparatus is conceivable. The light to be processed is emitted from the light source through the rectangular slit S provided in the mask used for the peripheral exposure. When the region of the identification mark is irradiated and the substrate to be processed is rotated by a predetermined angle in the horizontal direction and moved linearly, the exposure region EX of the identification mark provided on the substrate to be processed, for example, the wafer W, as shown in FIG. There is a possibility that the ridge line on the outer peripheral side of the wafer W in the exposure area EX rises outward and hits the chip of the adjacent circuit pattern.
[0006]
The present invention has been made in view of the above circumstances. By performing the peripheral exposure of the substrate to be processed on which the resist film is formed and the linear exposure of the identification mark region at the same place, the throughput is improved and the apparatus is downsized. An object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of achieving the above.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the substrate processing apparatus of the present invention forms a resist film by applying a resist solution to the surface of a substrate to be processed having a linear identification mark on the surface, and the resist film is formed. The first substrate processing apparatus according to the present invention is based on the premise of a substrate processing apparatus for developing the substrate to be processed after irradiating light to the surplus resist portion and the identification mark portion adhering to the peripheral portion of the substrate to be processed. Holding means for holding the surface of the substrate to be processed upward, rotating means for rotating the holding means, moving means for linearly moving the holding means and the rotating means in the horizontal direction, Exposure means for irradiating the surface with light, and the exposure means has a light source and a rectangular slit for adjusting an exposure area from the light source, and the light is applied to a predetermined region in the peripheral portion of the substrate to be processed. Induce A first mask, a second mask for adjusting an exposure area from the light source, a second mask for guiding light to an area of an identification mark on the substrate to be processed, and the first mask or the second mask. A mask moving mechanism for controlling switching of at least the second mask to a position immediately below the light source and a standby position deviating from the position directly below the light source. It is characterized (claim 1).
[0008]
Further, the second substrate processing apparatus of the present invention delivers the substrate to be processed to and from the transfer means for holding and transferring the substrate to be processed on which the resist film has been formed, and the surface of the substrate to be processed is Hold up Holding means and said holding means A rotating means that rotates the surface of the substrate to be processed, an exposure means that irradiates light on the surface of the substrate to be processed, and a holding means and a rotating means that are disposed horizontally between the conveying means and the exposing means. A moving means that moves linearly in the direction; and a detecting means that detects the amount of eccentricity from the center of the substrate to be processed held by the holding means. The exposure means includes a light source and a light source from the light source. It has a rectangular slit that adjusts the exposure area, a first mask that guides light to a predetermined region around the substrate to be processed, a circular slit that adjusts the exposure area from the light source, and light. A second mask for guiding the first mask to the region of the identification mark of the substrate to be processed, and at least the second mask so as to dispose the first mask or the second mask immediately below the light source. Position and light And a mask moving mechanism for performing a switching movement from the position directly below the source to the standby position (Claim 2).
[0009]
In the substrate processing apparatus of the present invention, the second mask moves the mask substrate so that the mask substrate having a plurality of circular slits of different sizes and the arbitrary circular slit are positioned immediately below the light source. It is good also as a structure which comprises a mask movement mechanism (Claim 3). Further, the second mask has a structure including a plurality of diaphragm pieces that cooperate with each other to form a variably adjustable circular slit, and a diaphragm piece moving mechanism that adjusts and moves each diaphragm piece. (Claim 4).
[0010]
A first substrate processing method of the present invention is a substrate processing method using the substrate processing apparatus according to claim 1, wherein the substrate to be processed on which the resist film is formed is rotated and the first mask is formed from the light source. A first exposure step of irradiating a predetermined region around the surface of the substrate to be processed through the rectangular slit, and the identification of the substrate to be processed from the light source through the circular slit of the second mask. And a second exposure step of irradiating the mark area with light and linearly moving the substrate to be processed while rotating the substrate in a horizontal direction by a predetermined angle (claim 5).
[0011]
A second substrate processing method of the present invention is a substrate processing method using the substrate processing apparatus according to claim 2, wherein the substrate to be processed on which the resist film is formed is held and transferred by a transfer means. A step of delivering to the holding means, a step of detecting the amount of eccentricity from the center of the substrate to be processed, and a position of the substrate to be processed and the holding means below the exposure means based on the information on the amount of eccentricity from the detected center. And a step of disposing a peripheral portion of the substrate to be processed at a position immediately below the light source of the exposure unit, and a predetermined region on the peripheral portion of the surface of the substrate to be processed through the rectangular slit of the first mask from the light source. A first exposure step of irradiating light; and an identification mark region of the substrate to be processed is disposed immediately below the light source on the basis of information stored in advance in the control means, and the second mask circle from the light source. The above-mentioned treatment through the shape slit After irradiating the region of the identification mark on the substrate with light and linearly moving the substrate to be processed while rotating the substrate by a predetermined angle in the horizontal direction, and after the first and second exposure steps are completed, And a step of delivering the substrate to be processed to the transfer means (claim 6).
[0012]
In the substrate processing method of the present invention, the second exposure step is a step of irradiating light through a selected circular slit among a plurality of circular slits of different sizes provided in the second mask. (Claim 7). Further, the second exposure step may be a step of irradiating light through a circular slit set by adjusting and moving a plurality of variable adjustable diaphragm pieces constituting the second mask ( Claim 8).
[0013]
According to the first, second, fourth, and fifth aspects of the present invention, the substrate to be processed on which the resist film is formed is rotated and the surface peripheral portion of the substrate to be processed is passed from the light source through the rectangular slit of the first mask. Irradiating light onto a predetermined region of the substrate {first exposure step}, irradiating light from the light source to the region of the identification mark of the substrate to be processed through the circular slit of the second mask, and processing The exposure process {second exposure step} in which the substrate is linearly moved while being rotated by a predetermined angle in the horizontal direction can be performed at the same light source, that is, at the same location. Therefore, it is possible to improve the throughput and reduce the size of the apparatus, and to improve the reliability of the apparatus.
[0014]
Further, in the first exposure step, a uniform amount of light can be irradiated to the peripheral portion of the surface of the substrate to be processed through the rectangular slit, so that the exposure accuracy at the boundary between the surplus resist portion and the other resist film portion Can be increased. In the second exposure step, accurate linear exposure corresponding to the linear identification mark region can be performed by the diameter of the circular slit, the rotation angle of the substrate to be processed, and the linear movement amount. There is no possibility that the exposure area is applied to the chip of the circuit pattern adjacent to the mark.
[0015]
According to the second and fifth aspects of the present invention, the amount of eccentricity from the center of the substrate to be processed is detected by the detecting means, and based on the detected information and the position information of the identification mark stored in advance, the substrate of the substrate to be processed is detected. Since the peripheral exposure {first exposure step} and the linear exposure {second exposure step} of the identification mark region can be controlled, the exposure processing accuracy can be improved and the reliability of the apparatus can be improved. Can be improved.
[0016]
According to the third, fourth, seventh, and eighth aspects of the present invention, the identification mark region is exposed through the circular slit selected from the plurality of circular slits of different sizes provided in the second mask. Or by adjusting a variably adjustable circular slit provided in the second mask, thereby linearly exposing the identification mark region corresponding to the size of the identification mark {second exposure step }It can be performed. Therefore, it is not necessary to separately prepare a second mask having a slit corresponding to the size and type of the identification mark, and the linear exposure {second exposure step} of the identification mark region can be performed with one mask. .
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings. In this embodiment, a case where the substrate processing apparatus according to the present invention is applied to a resist solution coating / development processing system for a semiconductor wafer will be described.
[0018]
FIG. 1 is a schematic plan view of an embodiment of the resist solution coating / developing system, FIG. 2 is a front view of FIG. 1, and FIG. 3 is a rear view of FIG.
[0019]
In the resist solution coating / developing system, a plurality of semiconductor wafers W (hereinafter referred to as wafers W), which are substrates to be processed, are carried into or out of the system from the outside in units of a plurality of, for example, 25 wafers in the wafer cassette 1. A cassette station 10 (carrying unit) for carrying wafers W in and out of the cassette 1 and various single-wafer processing units for performing predetermined processing on the wafers W one by one in the coating and developing process. An interface unit for transferring the wafer W between a processing station 20 having processing apparatuses arranged in multiple stages at a predetermined position and an exposure apparatus (not shown) provided adjacent to the processing station 20 30 is the main part.
[0020]
As shown in FIG. 1, the cassette station 10 includes a plurality of, for example, up to four wafer cassettes 1 at the position of the projection 3 on the cassette mounting table 2 with the respective wafer entrances facing the processing station 20 side. Wafer transfer tweezers 4 mounted in a line along the direction and movable in the cassette arrangement direction (X direction) and in the wafer arrangement direction (Z direction) of the wafer W accommodated in the wafer cassette 1 along the vertical direction. Is configured to be selectively transferred to each wafer cassette 1. Further, the wafer transfer tweezers 4 are configured to be rotatable in the θ direction, and are arranged in alignment units (ALIM) and extension units (EXT) belonging to a multi-stage unit portion of a third group G3 on the processing station 20 side described later. Can also be transported.
[0021]
As shown in FIG. 1, the processing station 20 is provided with a vertical transfer type main wafer transfer mechanism (substrate transfer mechanism, substrate transfer apparatus) 21 at the center, and a chamber 22 that houses the main wafer transfer mechanism 21. All processing units are arranged in multiple stages around one or more sets. In this example, five sets G1, G2, G3, G4 and G5 have a multi-stage arrangement configuration, and the first and second sets G1, G2 multi-stage units are arranged in parallel on the system front (front side in FIG. 8) side, The multistage unit of the third group G3 is arranged adjacent to the cassette station 10, the multistage unit of the fourth group G4 is arranged adjacent to the interface part 30, and the multistage unit of the fifth group G5 is arranged on the back side. Is arranged.
[0022]
In this case, as shown in FIG. 2, in the first group G1, the developing unit (DEV) that develops the resist pattern by facing the wafer W and the developer supply means (not shown) in the cup (container) 23. ) And a resist coating unit (COT) configured by the substrate processing apparatus according to the present invention for performing predetermined processing by placing the wafer W on a spin chuck (not shown), in order from the bottom in the vertical direction. It is stacked on the stage. Similarly, in the second group G2, two resist coating units (COT) and a developing unit (DEV) are stacked in two stages from the bottom in the vertical direction. The reason why the resist coating unit (COT) is arranged on the lower side in this way is that the drain of the resist solution is troublesome both in terms of mechanism and maintenance. However, the resist coating unit (COT) can be arranged in the upper stage as required.
[0023]
As shown in FIG. 3, in the third group G3, an oven-type processing unit that performs a predetermined process by placing the wafer W on the wafer mounting table 24, for example, a cooling unit (COL) that cools the wafer W, and the wafer W Adhesion unit (AD) for performing hydrophobic treatment, alignment unit (ALIM) for aligning wafer W, extension unit (EXT) for loading / unloading wafer W, and four hot plate units for baking wafer W (HP) is stacked, for example, in eight steps in order from the bottom in the vertical direction. Similarly, the fourth group G4 is an oven-type processing unit such as a cooling unit (COL), an extension / cooling unit (EXTCOL), an extension unit (EXT), a cooling unit (COL), and two chilling hot plate units having a rapid cooling function. (CHP) and two hot plate units (HP) are stacked in, for example, eight stages in order from the bottom in the vertical direction.
[0024]
As described above, the cooling unit (COL) and the extension cooling unit (EXTCOL) having a low processing temperature are arranged in the lower stage, and the hot plate unit (HP), the chilling hot plate unit (CHP) and the adhesion unit having a high processing temperature. By disposing (AD) in the upper stage, it is possible to reduce thermal mutual interference between units. Of course, a random multi-stage arrangement is also possible.
[0025]
As shown in FIG. 1, in the processing station 20, the third and fourth sets G3 and G4 of multistage units (spinner type processing units) adjacent to the first and second sets of G1 and G2 (spinner type processing units) ( Ducts 25 and 26 are vertically cut in the side walls of the oven-type processing unit. Downflow clean air or specially temperature-controlled air is allowed to flow through these ducts 25 and 26. By this duct structure, the heat generated in the oven type processing units of the third and fourth groups G3 and G4 is cut off and does not reach the spinner type processing units of the first and second groups G1 and G2. ing.
[0026]
Further, in this processing system, a fifth stage G5 multi-stage unit can be arranged on the back side of the main wafer transfer mechanism 21 as shown by a dotted line in FIG. The multistage units of the fifth group G5 can move sideways along the guide rail 27 as viewed from the main wafer transfer mechanism 21. Therefore, even when the multi-stage unit of the fifth group G5 is provided, the space portion is secured by sliding the unit, so that the maintenance work can be easily performed from the back with respect to the main wafer transfer mechanism 21.
[0027]
The interface unit 30 has the same dimensions as the processing station 20 in the depth direction, but is made small in the width direction. A portable pickup cassette 31 and a stationary buffer cassette 32 are arranged in two stages on the front part of the interface part 30, and the peripheral part of the wafer W and the identification mark area are exposed on the rear part. A peripheral exposure device 33 which is an exposure unit to be performed is provided, and a wafer transfer arm 34 which is a transfer unit is provided at the center. The transport arm 34 is configured to move in the X and Z directions and transport to both cassettes 31 and 32 and the peripheral exposure device 33. Further, the transfer arm 34 is configured to be rotatable in the θ direction, and the extension unit (EXT) belonging to the multi-stage unit of the fourth group G4 on the processing station 20 side and a wafer transfer table (not shown) on the adjacent exposure apparatus side. ) Can also be transported.
[0028]
The processing system configured as described above is installed in the clean room 40, and the cleanliness of each part is increased by an efficient vertical laminar flow method in the system.
[0029]
As shown in FIGS. 4 and 5, the peripheral exposure apparatus 33 includes a housing 50 that forms an exposure processing chamber 52 having a wafer W loading / unloading port 51 at one end. An exposure means 60 is attached to the upper part on the other end side. Further, in the casing 50, holding means for holding the wafer W so that the surface thereof is upward, for example, a chuck 80 for holding the wafer W by vacuum suction, and a motor 81 which is a rotating means for driving the chuck 80 to rotate. The moving means 90 for linearly moving the chuck 80 and the motor 81 in the horizontal direction (X direction) on the wafer transfer arm 34 side, that is, the wafer loading / unloading exit 51 side or the exposure means 60 side, and the wafer W held by the chuck 80 Detection means for detecting the amount of eccentricity from the center of the position detector 100, for example, a position detector 100 having a CCD camera, and the transfer arm 34 inserted into the housing 50 via the wafer loading / unloading port 51 and the chuck 80. And a buffer 85 which is a delivery means for delivering the wafer W.
[0030]
As shown in FIGS. 6 to 9, the exposure means 60 includes a light source 61 formed by, for example, an ultrahigh pressure mercury lamp, a condensing mirror 62 that condenses the light from the light source 61, and the light source 61 and the condensing light. A light source box 63 that houses the mirror 62; a rod 65 that is provided below the light source box 63 and guides light from the light source 61 to the lower optical system (lens group) 64; and a lower end opening of the rod 65. A cylinder which is disposed in the vicinity and accommodates a first mask 67 having a rectangular slit 66 (hereinafter referred to as a rectangular slit 66) for adjusting an exposure area, a rod 65, and an optical system (lens group) 64. The exposure area that is selectively incorporated between the rod 65 and the optical system (lens group) 64 via the cylindrical cover body 65b and the notch 65a provided on the side of the cylindrical cover body 65b is adjusted. Rectangular slip The second mask 69 having a circular slit 68 (hereinafter referred to as a circular slit 68) having a different size from that of the slit 66, for example, and the circular slit 68 of the second mask 69 is used as the light source 61. And a mask switching motor 70 that is a mask moving mechanism that controls switching to a standby position deviated from a position immediately below or directly below the light source 61.
[0031]
In this case, the size of the rectangular slit 66 provided in the first mask 67 is set to 4 mm × 5 mm or 4 mm × 10 mm, for example. The diameter of the circular slit 68 of the second mask 69 is set to a dimension that can cover an area of the alignment mark M provided on the wafer W, for example, 50 to 250 μm.
[0032]
In the exposure means 60 configured as described above, when the second mask 69 is in the standby position, a rectangular slit provided in the first mask 67 with the light B from the light source 61 as shown in FIG. A predetermined area in the peripheral portion of the surface of the wafer W is uniformly irradiated by being guided by 66. In this state, when the wafer W is rotated by the motor 81, the surplus resist film (region) RA on the periphery of the surface of the wafer W is irradiated with light B, that is, exposed (peripheral exposure) {first exposure step}. it can. In this way, by irradiating the periphery of the surface of the wafer W with a uniform amount of light through the rectangular slit 66, the exposure accuracy at the boundary between the surplus resist film (part) RA and the other resist film part can be improved. it can. Therefore, there is no possibility that the boundary surface of the resist film after the development processing is broken.
[0033]
Further, when the second mask 69 is inserted into the notch 65a provided in the cylindrical cover body 65b, that is, when the circular slit 68 is located immediately below the light source 61, as shown in FIG. The light B is guided by a circular slit 68 provided in the second mask 69, irradiates the resist film R in the region of the alignment mark M formed on the surface of the wafer W, and the wafer W is horizontal (θ direction). In this way, linear exposure (alignment mark exposure) {second exposure step} can be performed by linearly moving in the horizontal X direction while rotating at a predetermined angle.
[0034]
As shown in FIGS. 4 and 5, the moving means 90 includes a mounting table 91 on which the chuck 80 and the motor 81 are mounted, and the mounting table 91 on the wafer transfer arm 34 side, that is, the wafer loading / unloading port 51 side or exposure. It is mainly composed of a ball screw mechanism 92 moving to the means 60 side. In this case, the ball screw mechanism 92 includes a screw shaft 93 that engages (screws) the mounting table 91 so as to be movable in the axial direction, and a moving motor 94 that rotates the screw shaft 93 forward and backward. In addition, a pair of guide shafts 95 that are arranged in parallel with the screw shaft 93 and slidably support the mounting table 91 are provided. In the moving means 90 configured in this manner, the moving motor 94 is driven to rotate in the forward and reverse directions, whereby the chuck 80 and the motor 81 are moved to the wafer transfer arm 34 side, that is, the wafer loading / unloading exit 51 side or the exposure means 60. It is moved straight in the horizontal direction.
[0035]
Here, the case where the moving unit 90 is configured by the ball screw mechanism 92 has been described, but the moving unit 90 is not necessarily configured by the ball screw mechanism 92, and may be configured by, for example, a cylinder mechanism or a belt mechanism. May be.
[0036]
As shown in FIG. 4, the buffer 85 includes a support plate 86 having an arcuate notch 86 a surrounding the outside of the chuck 80 in plan view, and 3 near the arcuate notch 86 a side of the support plate 86. A support pin 87 that rises at a location, and an elevating mechanism that elevates and lowers the support plate 86 in the vertical direction of the chuck 80, for example, an elevating air cylinder 88 are provided. The buffer 85 configured as described above receives the wafer W held by the transfer arm 34 with the support pins 87 while being raised above the chuck 80 by driving the air cylinder 88, and thereafter, below the chuck 80. By descending, the wafer W is delivered to the chuck 80. Conversely, the wafer W held by the chuck 80 is lifted from the lower position of the chuck 80 so that the support pins 87 receive from the chuck, and then enter the casing 50 of the peripheral exposure apparatus 33 to enter the wafer W. It is configured to deliver the wafer W to the transfer arm 34 positioned below.
[0037]
The motor 81, the mask switching motor 70, the moving motor 94, the lifting air cylinder 88, and the position detector 100 are electrically connected to control means such as a central processing unit 200 (hereinafter referred to as CPU 200). , Based on information stored in the CPU 200 in advance, for example, information such as the distance from the edge of the wafer W to the chip of the circuit pattern, the position and dimensions of alignment (not shown), or detection from the position detector 100 Based on the signal, the motor 81, the mask switching motor 70, the moving motor 94, the lifting air cylinder 88 and the like are operated.
[0038]
Next, the operation of the resist solution coating / developing system will be described. First, in the cassette station 10, the tweezers 4 for wafer transfer access the cassette 1 containing unprocessed wafers W on the cassette mounting table 2, and take out one wafer W from the cassette 1. When the wafer tweezers 4 takes out the wafer W from the cassette 1, it moves to the alignment unit (ALIM) arranged in the multi-stage unit of the third group G3 on the processing station 20 side, and in the unit (ALIM) A wafer W is placed on the wafer mounting table 24. The wafer W undergoes orientation flat alignment and centering on the wafer mounting table 24. Thereafter, the main wafer transfer mechanism 21 accesses the alignment unit (ALIM) from the opposite side, and receives the wafer W from the wafer mounting table 24.
[0039]
In the processing station 20, the main wafer transfer mechanism 21 first carries the wafer W into an adhesion unit (AD) belonging to the multistage unit of the third group G3. Within this adhesion unit (AD), the wafer W is subjected to a hydrophobic treatment. When the hydrophobization process is completed, the main wafer transfer mechanism 21 unloads the wafer W from the adhesion unit (AD), and then cools the cooling units (belonging to the third group G3 or the fourth group G4 multi-stage unit). COL). In this cooling unit (COL), the wafer W is cooled to a set temperature before the resist coating process, for example, 23 ° C. When the cooling process is completed, the main wafer transfer mechanism 21 unloads the wafer W from the cooling unit (COL), and then to the resist coating unit (COT) belonging to the first group G1 or the second group G2 multistage unit. Carry in. In this resist coating unit (COT), the wafer W is coated with a resist with a uniform film thickness on the wafer surface by spin coating.
[0040]
When the resist coating process is completed, the main wafer transfer mechanism 21 unloads the wafer W from the resist coating unit (COT) and then loads it into the hot plate unit (HP). In the hot plate unit (HP), the wafer W is mounted on a mounting table and pre-baked at a predetermined temperature, for example, 100 ° C. for a predetermined time. As a result, the residual solvent can be removed by evaporation from the coating film on the wafer W. When pre-baking is completed, the main wafer transfer mechanism 21 unloads the wafer W from the hot plate unit (HP), and then transfers the wafer W to the extension cooling unit (EXTCOL) belonging to the multistage unit of the fourth group G4. In this unit (EXTCOL), the wafer W is cooled to a temperature suitable for the peripheral exposure process in the next process, that is, the peripheral exposure apparatus 33, for example, 24 ° C. After this cooling, the main wafer transfer mechanism 21 transfers the wafer W to the extension unit (EXT) immediately above, and places the wafer W on a mounting table (not shown) in the unit (EXT). When the wafer W is mounted on the mounting table of the extension unit (EXT), the transfer arm 34 of the interface unit 30 accesses from the opposite side to receive the wafer W. Then, the transfer arm 34 carries the wafer W into the peripheral exposure apparatus 33 in the interface unit 30. That is, the wafer W held by the transfer arm 34 is carried into the housing 50 of the peripheral exposure apparatus 33 and transferred to the support pins 87 of the raised buffer 85. Next, the support plate 86 of the buffer 85 is lowered, and the wafer W supported by the support pins 87 is held by the chuck 80. Then, the moving motor 94 of the moving unit 90 is driven to move the wafer W together with the chuck 80 to the exposure unit 60 side. At this time, a notch (not shown) provided at the edge of the wafer W is detected by the laser light emitted from the position detector 100 by rotating the motor 81 at a low speed, and the wafer held by the chuck 80. The amount of eccentricity from the center of W is detected, and a detection signal is transmitted to the CPU 200. Based on this, a control signal from the CPU 200 is transmitted to the movement motor 94, and the position of the peripheral portion of the wafer W held by the chuck 80 on the exposure means 60 side is set.
[0041]
When the wafer W is moved below the exposure unit 60, that is, directly below the light source 61 and the rod 65 of the exposure unit 60, the exposure unit 60 is activated, and the light B from the light source 61 is generated as shown in FIG. It is guided by a rectangular slit 66 provided in one mask 67 and uniformly irradiates a predetermined area on the periphery of the surface of the wafer W. In this state, the wafer 81 is rotated by the motor 81, and the surplus resist film (part) RA on the periphery of the surface of the wafer W is irradiated with the light B to perform exposure (peripheral exposure) {first exposure step}. . In this peripheral exposure {first exposure step}, a uniform amount of light can be irradiated to the peripheral portion of the surface of the wafer W through the rectangular slit 66, so that the surplus resist film (part) RA and other resist films The exposure accuracy at the boundary with the part can be increased. Therefore, there is no possibility that the boundary surface of the resist film after the development processing is broken.
[0042]
After the peripheral exposure is completed, the moving motor 94 is driven based on a control signal from the CPU 200, and the region of the alignment mark M formed (formed) on the wafer W is positioned immediately below the rod 65 of the exposure means 60. On the other hand, the switching motor 70 is driven to insert the second mask 69 into the notch 65 a provided in the cylindrical cover body 65 b, that is, to place the circular slit 68 directly below the light source 61. Specifically, the circular slit 68 is disposed between the rod 65 and the optical system (lens group) 64. In this state, the exposure means 60 operates, and as shown in FIG. 9, the light B from the light source 61 is guided by the circular slit 68 provided in the second mask 69, and is formed on the surface of the wafer W. The resist film R in the region of the mark M is irradiated, and the wafer W is linearly moved in the horizontal X direction by the moving means 90 while the wafer W is rotated by a predetermined angle in the θ direction by the motor 81 to perform linear exposure (alignment mark exposure). ) {Second exposure step} is performed.
[0043]
As a result, as shown in FIG. 10, the surplus resist portion at the peripheral portion of the wafer W is uniformly subjected to peripheral exposure EX1, and the resist film on the surface of the alignment mark M is linearly exposed EX2 (alignment mark exposure) along the alignment mark M. Is done. The width B of the exposure area (EX2) of the alignment mark M can be set by the diameter of the circular slit 68, and the length L of the exposure area (EX2) of the alignment mark M depends on the rotation angle of the wafer W in the θ direction and the wafer W. It can be set by the amount of linear movement in the X direction.
[0044]
The alignment mark exposure {second exposure step} does not need to be performed every time, and is set according to the state of the resist film applied to the wafer W, for example, whether the resist film layer is one layer or two layers.
[0045]
After the peripheral exposure and the alignment mark exposure are performed as described above, the moving motor 94 is driven to rotate in the reverse direction, and the wafer W together with the chuck 80 is moved to the loading / unloading port 51 side of the peripheral exposure apparatus 33. Moving. Next, the lift air cylinder 88 is driven to raise the support plate 86, and the wafer W on the chuck 80 is received by the support pins 87, and the wafer W is moved to a position above the chuck. Next, the transfer arm 34 enters below the wafer W in the housing 50 of the peripheral exposure apparatus 33, and the support plate 86 is lowered in this state, so that the wafer W is transferred to the transfer arm 34. Thereafter, the transfer arm 34 is retracted from the peripheral exposure apparatus 33 to carry out the wafer W and transfer it to a wafer receiving table (not shown) on the adjacent exposure apparatus side. In this case, the wafer W may be temporarily stored in the buffer cassette 32 before being transferred to the exposure apparatus.
[0046]
When the entire exposure is completed by the exposure apparatus and the wafer W is returned to the wafer receiving table on the exposure apparatus side, the transfer arm 34 of the interface unit 30 accesses the wafer receiving table to receive the wafer W, and receives the received wafer. W is loaded into an extension unit (EXT) belonging to the multi-stage unit of the fourth group G4 on the processing station 20 side, and placed on the wafer receiving table. Also in this case, the wafer W may be temporarily stored in the buffer cassette 32 in the interface unit 30 before being transferred to the processing station 20 side.
[0047]
The wafer W placed on the wafer receiving table is transferred to the chilling hot plate unit (CHP) by the main wafer transfer mechanism 21 to prevent fringes, or an acid catalyst in the chemically amplified resist (CAR). A post-exposure bake treatment is applied to induce the reaction.
[0048]
Thereafter, the wafer W is carried into a developing unit (DEV) belonging to the multistage unit of the first group G1 or the second group G2. In the developing unit (DEV), a developing solution is uniformly supplied to the resist on the surface of the wafer W to perform a developing process. By this development processing, the resist film formed on the surface of the wafer W is developed into a predetermined circuit pattern, and the surplus resist film in the peripheral portion of the wafer W is removed, and further, the resist film formed on the surface of the wafer W is applied (applied). E) The resist film adhering to the region of the alignment mark M is removed. In this way, when the development is completed, a rinse liquid is applied to the surface of the wafer W to wash away the developer.
[0049]
When the developing process is completed, the main wafer transfer mechanism 21 unloads the wafer W from the developing unit (DEV), and then the hot plate unit (HP) belonging to the third group G3 or the multistage unit of the fourth group G4. Carry in. In this unit (HP), the wafer W is post-baked for a predetermined time at 100 ° C., for example. Thereby, the resist swollen by development is cured, and chemical resistance is improved.
[0050]
When the post-baking is completed, the main wafer transfer mechanism 21 unloads the wafer W from the hot plate unit (HP), and then loads it into one of the cooling units (COL). Here, after the wafer W returns to room temperature, the main wafer transfer mechanism 21 next transfers the wafer W to the extension unit (EXT) belonging to the third group G3. When the wafer W is mounted on a mounting table (not shown) of the extension unit (EXT), the wafer transfer tweezers 4 on the cassette station 10 side accesses from the opposite side and receives the wafer W. The wafer transfer tweezers 4 put the received wafer W into a predetermined wafer storage groove of the processed wafer storage cassette 1 on the cassette mounting table, and the processing is completed.
[0051]
In the above-described embodiment, the case where one slit, for example, the circular slit 68 is formed in the second mask 69 has been described. However, the second mask 69 may have a structure as described below. For example, as shown in FIG. 11, the second mask 69A has a plurality of, for example, five circular slits 68a, 68b, 68c, 68d, 68e (68a>68b>68c>68d> 68e) having different sizes. Mask switching movement for moving the mask substrate 71 so that the mask substrate 71 having a substantially half donut shape in plan view and any circular slit of the circular slits 68 a, 68 b, 68 c, 68 d, 68 e are positioned immediately below the light source 61. You may comprise with the mechanism 72. FIG. In this case, the mask switching moving mechanism 72 includes a mask switching motor 70A formed by a stepping motor, and a connecting member 73 that connects the drive shaft 70a of the mask switching motor 70A and one end of the mask substrate 71. It is configured.
[0052]
According to the second mask 69A configured as described above, a predetermined one of the circular slits 68a, 68b, 68c, 68d, 68e based on information such as the size and shape of the alignment mark M stored in advance in the CPU 200. A circular slit having a size, for example, a circular slit 68 b can be positioned immediately below the light source 61 of the exposure means 60. Therefore, it is not necessary to separately prepare the second mask 69 having a circular slit corresponding to the size and type of the alignment mark M, and the linear exposure of the alignment mark region {second second mask 69A by the second mask 69A] Exposure step} can be performed. Note that the number of the circular slits 68a, 68b, 68c, 68d, and 68e is not necessarily five, and may be an arbitrary number corresponding to the type of the alignment mark M.
[0053]
As another form of the second mask, as shown in FIG. 12, a plurality of (for example, twelve) apertures that form a circular slit 68B that can be variably adjusted by cooperating with the second mask 69B. It can also be configured by a piece 74 and a diaphragm piece moving mechanism 75 that adjusts and moves each diaphragm piece 74. In this case, the diaphragm piece moving mechanism 75 mounts the drive tooth portion 76 on the drive shaft 70a of the switching motor 70B capable of forward and reverse rotation, and fixes the outer side of each diaphragm piece 74 to the inner periphery of the drive tooth portion 76. The driven tooth portion 78 provided on the outer periphery of the operation ring 77 is engaged.
[0054]
According to the second mask 69B configured in this way, each aperture piece 74 is obtained by rotating the switching motor 70B by a predetermined angle based on information such as the size and shape of the alignment mark M stored in advance in the CPU 200. Can cooperate to form a circular slit 68B of a predetermined size. The position of the alignment mark M is determined from the reference position of the notch position of the wafer W by obtaining circuit pattern information from a host computer of the CPU 200 such as a host computer through a network. Accordingly, it is not necessary to separately prepare the second mask 69 having a slit corresponding to the size and type of the alignment mark M, and the linear exposure of the alignment mark region {second exposure step by one second mask 69B. }It can be performed.
[0055]
In the embodiment described above, the peripheral exposure apparatus 33 performs the alignment mark exposure {second exposure step} after performing the peripheral exposure {first exposure step} of the wafer W. May be. That is, after performing the alignment mark exposure {second exposure step}, the peripheral exposure {first exposure step} may be performed.
[0056]
In the above embodiment, the first mask 67 is fixed at a position directly below the light source 61, and the second masks 69, 69A, and 69B are switched between the position immediately below the light source 61 and the standby position. However, such a structure is not necessarily required. For example, both the first mask 67 and the second masks 69, 69 </ b> A, 69 </ b> B may be configured to be movable between a position directly below the light source 61 and a standby position.
[0057]
Moreover, although the said embodiment demonstrated the case where the to-be-processed substrate was the semiconductor wafer W, the substrate processing apparatus and substrate processing method of this invention are applicable to circular other than the wafer W, for example, an LCD substrate, a photomask substrate, etc. The same applies.
[0058]
【The invention's effect】
As described above, according to the substrate processing apparatus and the substrate processing method of the present invention, the following effects can be obtained.
[0059]
1) According to the first, second, fourth, and fifth aspects of the present invention, the substrate to be processed on which the resist film is formed is rotated, and the surface of the substrate to be processed is passed from the light source through the rectangular slit of the first mask. An exposure process for irradiating light to a predetermined area in the peripheral portion {first exposure step}, and irradiating the area of the identification mark of the substrate to be processed from the light source through the circular slit of the second mask, Since the exposure process {second exposure process} in which the substrate to be processed is linearly moved while being rotated by a predetermined angle in the horizontal direction can be performed in the same light source, that is, in the same location, the throughput is improved and the apparatus is downsized. And the reliability of the apparatus can be improved.
[0060]
Further, in the first exposure step, a uniform amount of light can be irradiated to the peripheral portion of the surface of the substrate to be processed through the rectangular slit, so that the exposure accuracy at the boundary between the surplus resist portion and the other resist film portion Can be increased. In the second exposure step, accurate linear exposure corresponding to the linear identification mark region can be performed by the diameter of the circular slit, the rotation angle of the substrate to be processed, and the linear movement amount. There is no possibility that an exposure area is applied to the chip of the circuit pattern adjacent to the mark, and only the resist in the area of the identification mark can be accurately removed.
[0061]
2) According to the second and fifth aspects of the invention, the amount of eccentricity from the center of the substrate to be processed is detected by the detecting means, and the object to be processed is based on the detected information and the position information of the identification mark stored in advance. Since the peripheral portion exposure {first exposure step} and the identification mark region exposure {second exposure step} of the substrate can be controlled, the exposure processing accuracy can be improved and the reliability of the apparatus can be further improved. It is possible to improve the performance.
[0062]
3) According to the inventions of claims 3, 4, 7, and 8, the identification mark region is provided through the selected circular slit among the plurality of circular slits of different sizes provided in the second mask. Or by adjusting a variably adjustable circular slit provided in the second mask so as to correspond to the size of the identification mark {2 Exposure step} can be performed. Therefore, it is not necessary to separately prepare a second mask having a slit corresponding to the size and type of the identification mark, and the linear exposure {second exposure step} of the identification mark region can be performed with one mask. .
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing an example of a resist solution coating / development processing system to which a substrate processing apparatus according to the present invention is applied.
FIG. 2 is a schematic front view of the resist solution coating / developing system.
FIG. 3 is a schematic rear view of the resist solution coating / developing system.
FIG. 4 is a transverse sectional view showing exposure means in the present invention.
FIG. 5 is a longitudinal sectional view of the exposure means.
FIG. 6 is a schematic cross-sectional view (a) showing a peripheral exposure {first exposure step} by the exposure means, and a cross-sectional view (b) taken along line II of FIG. 6 (a).
FIG. 7 is a schematic perspective view (a) showing a peripheral exposure {first exposure step} by the exposure means, and an enlarged sectional view (b) taken along line II-II in (a).
FIG. 8 is a schematic cross-sectional view (a) showing alignment mark exposure {second exposure step} by the exposure means, and a cross-sectional view (b) taken along line III-III in (a).
FIG. 9 is a schematic perspective view (a) showing alignment mark exposure {second exposure step} by the exposure means and an enlarged cross-sectional view (b) taken along line IV-IV in FIG. 9 (a).
FIG. 10 is a plan view showing peripheral exposure {first exposure step} and linear exposure (alignment mark exposure) {second exposure step} by the exposure means.
FIG. 11 is a schematic perspective view showing a second embodiment of the second mask in the present invention.
FIG. 12 is a schematic perspective view showing a third embodiment of the second mask in the present invention.
FIG. 13 is an enlarged plan view showing linear exposure using a conventional mask having a rectangular slit.
[Explanation of symbols]
33 Peripheral exposure equipment
34 Transfer arm (transfer means)
51 Loading / unloading
60 exposure means
61 Light source
66 Rectangular slit
67 First mask
68, 68a, 68b, 68c, 68d, 68e Circular slit
68B Circular slit
69, 69A, 69B Second mask
70, 70A, 70B Mask switching motor
71 Mask substrate
72 Mask switching movement mechanism
74 Aperture piece
75 Aperture moving mechanism
80 Chuck (holding means)
81 Motor (rotating means)
85 buffer (delivery means)
90 Moving means
91 Mounting table
92 Ball screw mechanism
100 Position detector (detection means)
200 CPU (control means)
W Semiconductor wafer (substrate to be processed)
B light
M alignment mark
R resist film
RA Excess resist film (part)

Claims (8)

A resist solution is applied to the surface of the substrate to be processed with a linear identification mark on the surface to form a resist film, and the surplus resist portion attached to the peripheral portion of the substrate to be processed on which the resist film is formed and the above A substrate processing apparatus for developing the substrate to be processed after irradiating the identification mark with light,
Holding means for holding the surface of the substrate to be processed upward;
Rotating means for rotating the holding means;
Moving means for linearly moving the holding means and the rotating means in the horizontal direction;
Exposure means for irradiating light on the surface of the substrate to be processed;
The exposure means includes a light source, a rectangular slit that adjusts an exposure area from the light source, a first mask that guides light to a predetermined region in a peripheral portion of the substrate to be processed, and exposure from the light source. A second mask for guiding the light to the region of the identification mark on the substrate to be processed, and the first mask or the second mask are arranged at a position directly below the light source, and has a circular slit for adjusting the area. A substrate processing apparatus comprising: a mask moving mechanism that controls at least the second mask to switch to a position immediately below the light source and a standby position off the position directly below the light source. A resist solution is applied to the surface of the substrate to be processed with a linear identification mark on the surface to form a resist film, and the surplus resist portion attached to the peripheral portion of the substrate to be processed on which the resist film is formed and the above A substrate processing apparatus for developing the substrate to be processed after irradiating the identification mark with light,
A holding means for delivering the substrate to be processed and holding the substrate to be processed while holding the substrate to which the resist film is formed ;
Rotating means for rotating the holding means ;
Exposure means for irradiating light on the surface of the substrate to be processed;
A moving means for linearly moving the holding means and the rotating means in the horizontal direction on the conveying means side or the exposing means side between the conveying means and the exposure means;
Detecting means for detecting the amount of eccentricity from the center of the substrate to be processed held by the holding means,
The exposure means includes a light source, a rectangular slit that adjusts an exposure area from the light source, a first mask that guides light to a predetermined region in a peripheral portion of the substrate to be processed, and exposure from the light source. A second mask for guiding the light to the region of the identification mark on the substrate to be processed, and the first mask or the second mask are arranged at a position directly below the light source, and has a circular slit for adjusting the area. A substrate processing apparatus comprising: a mask moving mechanism that controls at least the second mask to switch to a position immediately below the light source and a standby position off the position directly below the light source. The substrate processing apparatus according to claim 1 or 2,
The second mask includes a mask substrate having a plurality of circular slits of different sizes, and a mask moving mechanism that moves the mask substrate to position any of the circular slits directly below the light source. A substrate processing apparatus. The substrate processing apparatus according to claim 1 or 2,
The second mask includes a plurality of diaphragm pieces that cooperate with each other to form a variably adjustable circular slit, and a diaphragm piece moving mechanism that adjusts and moves each diaphragm piece. Processing equipment. A substrate processing method using the substrate processing apparatus according to claim 1,
A first exposure step of rotating a substrate to be processed on which a resist film is formed and irradiating light from a light source to a predetermined region around the surface of the substrate to be processed through a rectangular slit of the first mask;
A second exposure that irradiates light from the light source through the circular slit of the second mask to the area of the identification mark of the substrate to be processed and linearly moves the substrate to be processed while rotating the substrate to be processed by a predetermined angle in the horizontal direction. And a substrate processing method. A substrate processing method using the substrate processing apparatus according to claim 2,
Holding and transferring the substrate to be processed on which the resist film is formed by a transfer means, and transferring to the holding means;
Detecting the amount of eccentricity from the center of the substrate to be processed;
Moving the substrate to be processed and the holding unit below the exposure unit based on the detected amount of eccentricity from the center, and disposing the peripheral portion of the substrate to be processed at a position directly below the light source of the exposure unit; ,
A first exposure step of irradiating light from a light source to a predetermined region of the peripheral portion of the surface of the substrate to be processed through a rectangular slit of the first mask;
Based on the information stored in advance in the control means, an identification mark region of the substrate to be processed is disposed immediately below the light source, and the light source of the substrate to be processed passes through a circular slit of a second mask from the light source. A second exposure step of irradiating the region of the identification mark with light and linearly moving the substrate to be processed while rotating the substrate in a horizontal direction by a predetermined angle;
And a step of transferring the substrate to be processed to the transfer means after the first and second exposure steps are completed. The substrate processing method according to claim 5 or 6,
In the second exposure step, light is irradiated through a circular slit selected from a plurality of circular slits of different sizes provided in the second mask. The substrate processing method according to claim 5 or 6,
The second exposure step irradiates light through a circular slit set by adjusting and moving a plurality of variable adjustable diaphragm pieces constituting the second mask.

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