JP5559736B2 - Substrate heating apparatus, coating and developing apparatus including the same, and substrate heating method - Google Patents

Description

  The present invention relates to a substrate heating apparatus that heats a substrate such as a semiconductor wafer or a glass substrate for a flat panel display (FPD), a coating and developing apparatus including the substrate heating apparatus, and a substrate heating method.

  In the manufacturing process of a semiconductor device or a flat panel display (FPD), for example, after a photoresist film is formed on a semiconductor wafer or a glass substrate for FPD, various heat treatments including pre-baking for heating the photoresist film are performed. Is done. A predetermined heating device is used for pre-baking, and the substrate is heated to a temperature corresponding to the photoresist film to be used in the heating device.

JP 2006-222124 A JP 2007-329008 A

  By the way, for example, in the course of processing a plurality of wafers in one lot, it may be necessary to change the photoresist film to be used. With the change of the photoresist film, for example, the pre-bake temperature of the photoresist film needs to be changed. Such a change is necessary, for example, when the circuit pattern of the semiconductor device to be manufactured changes, and in accordance with this change, the photomask used for exposing the photoresist film is also replaced in the exposure apparatus. That is, along with the change of the circuit pattern, the photoresist solution to be used is changed, the prebake temperature is changed, and the photomask is changed.

  Since the photomask can be replaced in a short time by improving the exposure apparatus in recent years, the change of the pre-bake temperature is becoming rate-limiting the exposure process of the photoresist film. Considering the running cost of the exposure apparatus, it is not preferable to maintain the exposure apparatus in a standby state. For this reason, the request | requirement with respect to changing a prebaking temperature rapidly is increasing.

When changing the temperature of the hot plate in the heating device, it is relatively easy to raise the temperature, but it tends to take time to lower the temperature. In order to rapidly reduce the temperature, it is effective to reduce the heat capacity by thinning the heat plate.
However, when the hot plate is thinned, the hot plate is easily bent, and as a result, the interval between the hot plate and the substrate may be non-uniform. If it does so, nonuniformity may arise in the heating temperature of a board | substrate.

  The present invention has been made in view of the above circumstances, and a substrate heating apparatus capable of uniformly heating a substrate even when using a heating plate having a reduced thickness for quick change in temperature, A coating and developing apparatus and a substrate heating method including the same are provided.

According to a first aspect of the present invention, there is provided a heating plate that includes a heating element that heats a substrate and has a flexibility that curves in a concave shape due to its own weight when attached at a peripheral portion, and the heating plate is provided on the heating plate. A substrate heating apparatus comprising: a substrate support member to be supported; and a decompression unit that decompresses a space between the substrate supported by the substrate support member disposed in the vicinity of the periphery of the heating plate and the curved heating plate. provide.

According to a second aspect of the present invention, there is provided a substrate support provided on the heating plate, which includes a heating element for heating the substrate and has a flexibility to bend in a concave shape by its own weight when attached to the peripheral portion. Placing the substrate via a member; and depressurizing a space between the substrate supported by the substrate support member disposed near the periphery of the heating plate and the curved heating plate. A substrate heating method is provided.

  According to an embodiment of the present invention, a substrate heating apparatus capable of uniformly heating a substrate even when a heating plate having a reduced thickness for rapid change in temperature is used, and coating provided with the same A developing device and a substrate heating method are provided.

1 is a schematic top view showing a coating and developing apparatus according to an embodiment of the present invention. It is a schematic plan view which shows the coating and developing apparatus of FIG. It is a schematic side view which shows the coating and developing apparatus of FIG. It is a schematic perspective view which shows the 3rd block in the coating and developing apparatus of FIG. It is a schematic side view which shows the principal part of the heating apparatus by embodiment of this invention. It is a figure which shows the hot platen in the heating apparatus of FIG. It is a figure which shows the cooling plate in the heating apparatus of FIG. It is a figure explaining the heating method by embodiment of this invention. FIG. 9 is a diagram for explaining the heating method according to the embodiment of the present invention following FIG. 8. It is a schematic side view which shows the principal part of the heating apparatus by other embodiment of this invention. It is a perspective view which shows the cyclic | annular cover member in the heating apparatus of FIG. It is a figure explaining the heating method by other embodiment of this invention. FIG. 13 is a diagram for explaining a heating method according to another embodiment of the present invention, following FIG. 12. It is a graph which shows the result of the experiment conducted in order to confirm the effect of the heating apparatus by embodiment of this invention. It is a schematic side view which shows the principal part of the heating apparatus by another embodiment of this invention.

  Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In all the attached drawings, the same or corresponding members or parts are denoted by the same or corresponding reference numerals, and redundant description is omitted. Also, the drawings are not intended to show the relative ratios between members or parts, so specific dimensions should be determined by those skilled in the art in light of the following non-limiting embodiments.

(First embodiment)
First, a coating and developing apparatus according to a first embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, the coating and developing apparatus 100 is provided with a carrier station S1, a processing station S2, and an interface station S3 arranged in this order. An exposure device S4 is coupled to the coating station 100 on the interface station S3 side.

  The carrier station S1 includes a mounting table 21 and a transport mechanism C. On the mounting table 21, a carrier 20 in which a predetermined number (for example, 25) of semiconductor wafers (hereinafter referred to as wafers) W is placed is placed. In the present embodiment, four carriers 20 can be mounted side by side on the mounting table 21. In the following description, as shown in FIG. 1, the direction in which the carriers 20 are arranged is defined as the X direction, and the direction orthogonal thereto is defined as the Y direction. The transport mechanism C takes out the wafer W from the carrier 20 and transports it to the processing station S <b> 2, and receives the processed wafer W processed in the processing station S <b> 2 and stores it in the carrier 20.

  As shown in FIGS. 1 and 2, the processing station S2 includes a shelf unit U1, a shelf unit U2, a first block (DEV layer) B1, a second block (BCT layer) B2, and a third block (COT layer). B3 and a fourth block (TCT layer) B4.

As shown in FIG. 3, the shelf unit U1 includes, for example, delivery modules TRS1, TRS1, CPL11, CPL2, BF2, CPL3, BF3, CPL4, and TRS4 stacked in order from the bottom. Further, as shown in FIG. 1, a transport mechanism D that can be raised and lowered is provided on the + X direction side of the shelf unit U1, and the wafer W is transported by the transport mechanism D between the modules of the shelf unit U1.
As illustrated in FIG. 3, the shelf unit U2 includes delivery modules TRS6, TRS6, and CPL12 stacked in order from the bottom, for example.

  Among the delivery modules, some delivery modules to which reference numeral “CPL + number” is attached also serve as a heating module for heating the wafer W. The wafer W is cooled to a predetermined temperature (for example, 23 ° C.). Some of them also serve as a cooling module to be maintained. The delivery module to which reference numeral “BF + number” is attached also serves as a buffer module on which a plurality of wafers W can be placed. In addition, the transfer modules TRS, CPL, BF and the like are provided with a mounting portion on which the wafer W is mounted.

  Next, the third block B3 of the processing station S2 will be described with reference to FIG. As shown in FIG. 4, the third block B3 includes a coating module 23, a shelf unit U3, and a transport mechanism A3. The coating module 23 is provided with a coating unit (not shown) that supplies a photoresist solution onto the wafer W and rotates the wafer W to form a photoresist film. The shelf unit U3 is arranged so as to face the coating module 23 and has a heat treatment module TM. The heat treatment module TM includes a pre-processing unit for performing pre-processing before forming a photoresist film in the coating module 23, a pre-baking unit for heating the formed photoresist film, and a post-baking unit for heating the exposed photoresist film. The heating device according to the embodiment of the present invention, which will be described later, is also arranged in the shelf unit U3 as a heat treatment module. The transport mechanism A3 includes two forks 3A and 3B, a base 31, a rotation mechanism 32, and a lifting platform 34. The elevating table 34 is provided so as to be movable up and down by an elevating mechanism along a Z-axis guide rail (not shown) extending linearly in the vertical direction (Z-axis direction in FIG. 4). As the elevating mechanism, a ball screw mechanism, a mechanism using a timing belt, or the like can be used. In this example, the Z-axis guide rail and the elevating mechanism are each covered by a cover body 35, and are connected and integrated, for example, on the upper side. The cover body 35 is configured to slide along a Y-axis guide rail 36 that extends linearly in the Y-axis direction. With such a configuration, the transfer mechanism A3 carries the wafer W between the heat treatment modules TM and between the heat treatment modules TM and the coating module 23.

  Referring to FIGS. 1 and 3 again, the first block B1 is provided with a developing module 22, a transport mechanism A1, and a shuttle arm E. Specifically, there are two developing modules 22 in the first block B1, which are stacked one above the other. Each developing module 22 is provided with a developing unit that supplies a developing solution to the wafer W having the exposed photoresist film and develops the photoresist film.

  The second block B2 and the fourth block B4 have the same configuration as the third block B3. However, in the second block B2, a chemical solution for an antireflection film is supplied to the wafer W instead of the photoresist solution, and a lower antireflection film serving as a base layer of the photoresist film is formed. Also in the fourth block B4, the chemical solution for the antireflection film is supplied to the wafer W, and an upper antireflection film is formed on the photoresist film. In addition, as shown in FIG. 3, the reference symbol A2 is attached to the transport mechanism of the second block B2, and the reference symbol A4 is attached to the transport mechanism of the fourth block B4.

  The interface station S3 is provided with an interface arm F as shown in FIGS. The interface arm F is disposed on the + Y direction side of the shelf unit U2 of the processing station S2. The wafer W is transferred by the interface arm F between each module of the shelf unit U2 and between each module and the exposure apparatus S4.

  In the coating and developing apparatus 100 having the above-described configuration, the wafer W is transferred to each module as described below, a photoresist film is formed, and the exposed photoresist film is developed. First, the wafer W is taken out from the carrier 20 on the mounting table 21 by the transfer mechanism C of the carrier station S1, and transferred to the delivery module CPL2 of the shelf unit U1 of the processing station S2 (see FIG. 3). The wafer W transferred to the delivery module CPL2 is sequentially transferred to the heat treatment module and the coating module of the second block B2 by the transfer mechanism A2 of the second block B2, and a lower antireflection film is formed on the wafer W. .

The wafer W on which the lower antireflection film is formed is transferred to the transfer module BF2 of the shelf unit U1 by the transfer mechanism A2, and is transferred to the transfer module CPL3 of the shelf unit U1 by the transfer mechanism D (FIG. 1). Next, the wafer W is received by the transfer mechanism A3 of the third block B3, and is sequentially transferred to the heat treatment module TM and the coating module 23 (FIG. 3) of the third block B3, and a photoresist is formed on the lower antireflection film. A film is formed.
The wafer W on which the photoresist film is formed is transferred to the delivery module BF3 of the shelf unit U1 by the transfer mechanism A3.

  Note that an antireflection film may be further formed on the wafer W on which the photoresist film is formed in the fourth block B4. In this case, the wafer W is received by the transfer mechanism A4 of the fourth block B4 via the transfer module CPL4, and sequentially transferred to the heat treatment module and the coating module of the fourth block B4, and the upper reflection prevention is performed on the photoresist film. A film is formed. Thereafter, the wafer W is transferred to the transfer module TRS4 of the shelf unit U1 by the transfer mechanism A4.

  The wafer W on which the photoresist film (or the upper antireflection film is further formed) is transferred by the transfer mechanism D from the transfer module BF3 (or the transfer module TRS4) to the transfer module CPL11. The wafer W transferred to the transfer module CPL11 is transferred by the shuttle arm E to the transfer module CPL12 of the shelf unit U2, and then received by the interface arm F of the interface station S3.

  Thereafter, the wafer W is transferred to the exposure apparatus S4 by the interface arm F, and a predetermined exposure process is performed. The wafer W subjected to the exposure processing is transferred to the delivery module TRS6 of the shelf unit U2 by the interface arm F, and returned to the processing station S2. The wafer W returned to the processing station S2 is transferred to the first block B1, where development processing is performed. The wafer W on which the development processing has been performed is transferred to one of the delivery modules of the shelf unit U1 by the transfer mechanism A1, and returned to the carrier 20 by the transfer mechanism C.

(Second Embodiment)
Next, a heating apparatus according to a second embodiment of the present invention will be described with reference to FIGS. This heating apparatus is used as the heat treatment module TM (FIG. 4) of the third block B3 in the coating and developing apparatus 100 described above. FIG. 5 is a schematic diagram showing a main part of the heating device 50. In FIG. 5, the casing is omitted except for the transport port 24.

  As shown in the figure, the heating device 50 includes a hot plate 51 on which the wafer W is mounted, the heated wafer 51 for heating the mounted wafer W, a casing 52 having a bottomed cylindrical shape and supporting the peripheral portion of the hot plate 51, Three lift pins 53 (only two are shown in FIG. 5) that can move up and down through the through hole 51H formed in the hot plate 51 and the through hole 52H formed in the casing 52, and the side part of the casing 52 from the outside to the inside And a plurality of gas nozzles 54 penetrating the gas.

  The hot plate 51 is airtightly attached to the casing 52 through, for example, a silicone sheet at the peripheral edge portion, whereby the hot plate 51 and the casing 52 form a chamber 50C. The heat plate 51 is formed with a plurality of intake holes 51V that communicate the space above the heat plate 51 with the space in the chamber 50C. A plurality of spacers 51 </ b> S that support the wafer W are provided on the upper surface of the hot plate 51.

  Referring to FIG. 6A, the hot platen 51 in this embodiment includes a base 51B, a heater 51HE attached to the back surface of the base 51B, a flexible printed circuit (FPC) board 51F, a base 51B and a heater. The insulating resin 51R is used to join the 51HE and the FPC board 51F. The substrate 51B is made of, for example, a silicon carbide disk having a thickness of 100 μm to 500 μm and a diameter of 310 mm to 350 mm, for example. Referring to FIG. 6B showing the upper surface of the base material 51B, the base material 51B has three through holes 51H that allow the lift pins 53 (FIG. 5) to move up and down.

  The plurality of spacers 51S described above are disposed along the center of the base material 51B and two concentric circles. However, the number and arrangement of the plurality of spacers 51S are not limited to the illustrated example. The number and arrangement of the plurality of spacers 51S may be appropriately determined as long as the gap between the wafer W and the base material 51B can be maintained at a substantially constant width. Further, as described later, the height of the spacer 51S is determined to such an extent that a depressurizable space is maintained between the wafer W supported on the hot plate 51 by the spacer 51S and the hot plate 51, for example, 30 μm. To 500 μm, and preferably from 50 μm to 200 μm. The spacer 51S can be realized, for example, by forming a countersink on the upper surface of the base material 51B and placing a sphere made of ceramics or the like on the countersink. Further, when the base material 51B is made of, for example, silicon carbide, a plurality of protrusions arranged in a predetermined pattern may be formed and used as the spacer 51S. The protrusions in this case can have a pin shape, a dome shape, a cylindrical shape, or the like.

In the illustrated example, the base 51B is provided with eight intake holes 51V, but the number of intake holes 51V may be determined as appropriate. Specifically, the intake hole 51V is preferably provided so that the space between the wafer W supported on the hot plate 51 by the spacer 51S and the hot plate 51 can be decompressed.
Further, as shown in FIG. 6C, the heater 51HE attached to the back surface of the base material 51B has two substantially concentric circular shapes, which can heat the base material 51B uniformly. it can. The heater 51HE can be made of polyimide, for example. That is, the heater 51HE can be manufactured by forming a polyimide film on the back surface of the substrate 51B and patterning it. However, the heater 51HE may be formed of platinum. In this case, the heater 51H can be manufactured by depositing a platinum film, for example, by sputtering on the back surface of the substrate 51B and patterning the platinum film by photolithography.

The FPC board 51F has a thickness of, for example, 50 μm to 200 μm including a bump 51FB to be described later, and has a diameter substantially equal to the diameter of the base material 51B. As shown in FIG. 6A, bumps 51FB corresponding to the pattern of the heater 51HE are formed on the upper surface of the FPC board 51F. Each bump 51FB is electrically connected to a pad 51FP formed on the back surface of the FPC board 51F by a through electrode 51FE penetrating the FPC board 51F. Further, the FPC board 51F is attached to the back surface of the base material 51B by an insulating resin 51R so that the bumps 51FB are pressed against the heater 51HE. With such a configuration, when the power source PS is connected to the pad 51FP of the FPC board 51F and a current flows, a current flows to the heater 51HE through the pad 51FP, the through electrode 51FE, and the bump 51FB, and the heater 51HE generates heat. Thereby, the base material 51B is heated, and the wafer W (FIG. 5) mounted on the base material 51B via the spacer 51S is heated. The temperature is measured by a temperature sensor (for example, a thermocouple, a platinum resistor, a radiation thermometer, etc.) (not shown), and the output of the power source PS is controlled based on the measured temperature, depending on the photoresist film on the wafer W. The wafer W is heated at the heating temperature.
The hot plate 51 configured as described above has a diameter of 320 mm to 350 mm, for example, and its thickness is relatively thin, for example, 300 μm to 1000 μm, and is attached to the casing 52 at the periphery thereof. For this reason, it is normally curved in a concave shape by its own weight. Moreover, since it is thin as described above, the heat capacity of the hot plate 51 is small, and therefore the temperature of the hot plate 51 can be changed quickly. In other words, in the present embodiment, from the viewpoint of quick temperature change, the hot plate 51 is made thin enough to be bent in a concave shape by its own weight.
As shown in FIG. 6A, the through hole 51H and the intake hole 51V formed in the hot plate 51 penetrate the base material 51B, the FPC board 51F, and the insulating resin 51R.

  Referring again to FIG. 5, an exhaust pipe 52 </ b> V is connected to substantially the center of the bottom of the casing 52. The exhaust pipe 52V is connected to a vacuum exhaust device (pump) 60, and when the pump 60 is activated, the inside of the chamber 50C is exhausted through the exhaust pipe 52V. When the inside of the chamber 50C is exhausted by the pump 60 when the wafer W is placed on the hot plate 51 (the spacer 51S), the space between the hot plate 51 and the wafer W through the intake hole 51V of the hot plate 51. Is exhausted. Then, since the space is decompressed, the hot plate 51 and the wafer W are pulled with each other. Therefore, a uniform distance determined by the height of the spacer 51S is maintained between the hot plate 51 and the wafer W. .

Further, as shown in FIG. 5, a gas supply system 56 is connected to the gas nozzle 54 that penetrates the side portion of the casing 52. Gas supply system 56 is provided with a gas supply source 56a, and piping 56b which connects the gas supply source 56a and the gas nozzle 54, an opening and closing valve 5 6 c and 5 6 d provided in the pipe 56b, the pipe 56b flow And a controller 56e. The gas supply source 56a stores, for example, clean gas such as nitrogen gas or clean air at a predetermined pressure. With such a configuration, when the on-off valves 5 6 c and 5 6 d are opened, clean gas is supplied into the chamber 50 C through the gas nozzle 54 at a flow rate controlled by the flow rate controller 56 e, and on the back surface of the hot plate 51. Clean gas is blown. This clean gas promotes cooling of the hot plate 51.

  Although two gas nozzles 54 are shown in FIG. 5, for example, three or more gas nozzles 54 are provided on the side of the casing 52 at a predetermined interval, and clean gas is supplied at substantially the same flow rate from either of them. Is preferred. The number of gas nozzles 54 is preferably 6 to 8, for example.

Further, as shown in FIG. 5, the heating device 50 transfers the wafer W between the transfer mechanism A <b> 3 arranged in the third block B <b> 3 of the coating and developing device 100 and the hot plate 51 of the heating device 50. A cooling plate CP also serving as an arm is provided. The cooling plate CP can be moved between a position facing the transfer port 24 and a position above the hot plate 51 by a moving mechanism (not shown) as indicated by an arrow AR in the drawing. As shown in FIG. 7A, the cooling plate CP has a width slightly larger than the diameter of the wafer W so that the wafer W can be placed thereon. The cooling plate CP is provided with two slits SL. These slits SL are formed corresponding to the lift pins 53 so that the three lift pins 53 can pass through the cooling plate CP. Further, a conduit CPC through which the cooled medium flows is formed inside the cooling plate CP, and the cooling plate CP is cooled to a predetermined temperature by circulating the medium from the temperature control device (not shown) through the conduit CPC. For this reason, when the wafer W heated by the hot plate 51 is received by the cooling plate CP, it immediately begins to be cooled by the cooling plate CP. Therefore, for example, the time required for cooling can be shortened as compared with the case where the wafer W is cooled by a predetermined cooling module after being unloaded from the heating device 50.
The effects and advantages exhibited by the heating device 50 having the above-described configuration will become more apparent from the following description.

(Third embodiment)
Next, the case where the substrate heating method according to the third embodiment of the present invention is performed using the above-described heating device 50 will be described with reference to FIGS. 8 and 9. In the following, a case where one wafer W is heated to the first temperature and then the next wafer W is heated to a second temperature lower than the first temperature will be described as an example.
First, predetermined power is supplied to the hot plate 51 from the power source PS (shown only in FIG. 6A), and the hot plate 51 is maintained at the first temperature. Next, as shown in FIG. 8A, the wafer W is transferred by the cooling plate CP and maintained above the hot platen 51. Next, as shown in FIG. 8B, the lift pins 53 are lifted by a lifting mechanism (not shown) to lift the wafer W on the cooling plate CP, and the cooling plate CP is retracted from a position above the hot plate 51. Thereafter, when the lift pins 53 are lowered, the wafer W is supported by the spacers 51 </ b> S on the hot plate 51. At this time, the hot plate 51 is bent by its own weight and curved in a concave shape, and the wafer W is supported by spacers 51 </ b> S provided mainly on the peripheral side of the hot plate 51.

  At the same time as the wafer W is supported by the spacer 51S (or slightly delayed), the space between the hot plate 51 and the casing 52 (the space in the chamber 50C) passes through the exhaust pipe 52V and the exhaust device 60 (FIG. 5 only). ). Accordingly, as indicated by an arrow A in FIG. 8C, the space between the wafer W and the hot plate 51 is exhausted through the intake holes 51V of the hot plate 51, and the pressure in this space is higher than the atmospheric pressure. Also lower. Then, the wafer W and the hot plate 51 come close to each other while being deformed, and the distance between the wafer W and the hot plate 51 is maintained almost constant by the spacer 51S. Therefore, heat is uniformly transmitted from the hot plate 51 over the entire surface of the wafer W, and thus the entire wafer W is heated uniformly.

  After heating the wafer W at the first temperature for a predetermined period, the exhaust by the exhaust device 60 is stopped, and the lift pins 53 are raised, so that the wafer W is removed from the hot plate 51 as shown in FIG. lift. Next, when the cooling plate CP is moved between the wafer W and the hot plate 51 and the lift pins 53 are lowered, the wafer W is received by the cooling plate CP. Thereafter, the cooling plate CP moves to the transfer port 24 side, and the wafer W is transferred from the cooling plate CP to the interface arm 67 and unloaded from the heating device 50.

On the other hand, the electric power supplied from the power source PS to the hot plate 51 is adjusted, and the hot plate 51 is changed to the second temperature (<first temperature). As described above, the heat plate 51 is thin enough to bend due to its own weight and bend into a concave shape, so that the heat capacity is small. Therefore, the temperature is quickly changed to the second temperature. At this time, cooling of the hot plate 51 may be promoted by supplying a clean gas from the gas nozzle 54 into the chamber 50C.
Subsequently, the next wafer W is carried in by the cooling plate CP (see FIG. 8A). Thereafter, the wafer W is carried out in the same manner as described with reference to FIGS. 8B to 9E. W is heated at the second temperature and unloaded from the heating device 50.

As described above, in the substrate heating method according to the present embodiment, the wafer W is placed on the hot plate 51 that is thin enough to be bent by its own weight and curved in a concave shape, with the spacer 51S interposed therebetween. Since the space between them is depressurized by the exhaust device 60 through the intake holes 51V of the hot plate 51, the wafer W and the hot plate 51 are deformed with each other. As a result, the distance between the wafer W and the hot plate 51 is maintained substantially constant by the spacer 51S. Therefore, the heat from the hot plate 51 is uniformly propagated to the wafer W, so that the wafer W is uniformly heated.

  Moreover, since the heat plate 51 is thin and the heat capacity is small as described above, the temperature of the heat plate 51 can be quickly changed. Further, the heating device 50 according to the present embodiment is provided with a gas nozzle 54 that penetrates the side portion of the casing 52 to reach the inside of the chamber 50 </ b> C and supplies clean gas toward the hot plate 51. For this reason, when the temperature of the hot plate 51 is lowered, the cooling of the hot plate 51 can be promoted by the clean gas from the gas nozzle 54.

  Therefore, in the exposure apparatus S4 used with the coating and developing apparatus 100 including the heating apparatus 50 according to the embodiment of the present invention, the temperature change in the hot plate 51 can be completed while the photomask (reticle) is replaced. Therefore, it is not necessary to make the exposure apparatus stand by for changing the temperature of the hot plate 51 of the heating device 50.

(Fourth embodiment)
Next, a heating device according to a fourth embodiment of the present invention will be described with reference to FIGS. 10 and 11 focusing on differences from the heating device 50 shown in FIG.
Referring to FIG. 10, the heating device 501 of the present embodiment has an annular lid member 57 placed on the bottom surface of the casing 52. As shown in FIG. 11, the annular cover member 57 has three lift pins 53 which are fixed through the annular cover member 57 is provided. The lift pins 53 are lifted and lowered by a lift mechanism (not shown) in the same manner as the lift pins 53 in the heating device 50 shown in FIG. Accordingly, when the lift pins 53 are lifted to receive the wafer W from the cooling plate CP or when the wafer W is transferred, the annular lid member 57 is also lifted as shown in FIG. There is a gap in

  On the other hand, in the casing 52, two openings 52a having a substantially C shape and facing each other are formed below the annular lid member 57. The opening 52 a is closed by the annular lid member 57 when the annular lid member 57 is placed on the bottom surface of the casing 52, and opened when the annular lid member 57 is lifted together with the lift pin 53.

Referring again to FIG. 10, the branch pipe 58 branches from the pipe 56 b of the gas supply system 56, and the branch pipe 58 opens and closes to the exhaust pipe 60 </ b> L that connects the exhaust pipe 52 </ b> V at the bottom of the casing 52 and the exhaust device 60. They merge through the valve 58a. In addition, an opening / closing valve 60a is provided in the exhaust pipe 60L on the exhaust device 60 side of the junction. Here, by closing the on-off valve 58a and opening the on-off valve 60a, the space between the hot plate 51 and the casing 52 (the space in the chamber 50C) can be exhausted by the exhaust device 60. Conversely, when the opening / closing valve 58a is opened and the opening / closing valve 60a is closed, the clean gas from the gas supply system 56 can be supplied to the hot plate 51 also from the exhaust pipe 52V.
The effects and advantages exhibited by the heating device 501 having the above-described configuration will become more apparent from the following description.

(Fifth embodiment)
Next, a substrate heating method according to an embodiment of the present invention, which is performed using the above-described heating device 501, will be described with reference to FIGS. 12 and 13. In the following, as an example, a case where one wafer W is heated to a first temperature and then the next wafer W is heated to a second temperature lower than the first temperature will be described.
First, the hot plate 51 is maintained at the first temperature, and the wafer W is transferred by the cooling plate CP and is maintained above the hot plate 51 (FIG. 12A). Next, the lift pins 53 are raised by an elevating mechanism (not shown) to lift the wafer W on the cooling plate CP, and the cooling plate CP is retracted from a position above the hot plate 51 (FIG. 12B). Thereafter, when the lift pins 53 are lowered, the wafer W is supported by the spacers 51 </ b> S on the hot plate 51. Also in this case, the hot plate 51 is bent by its own weight and curved in a concave shape, and the distance between the wafer W and the hot plate 51 is wide at each central portion.

  At the same time as the wafer W is supported by the spacer 51S (or slightly delayed), the open / close valve 60a is opened while the open / close valve 58a is closed, whereby the space in the chamber 50C is exhausted by the exhaust device 60 (FIG. 10). The Accordingly, as indicated by an arrow A in FIG. 12C, the space between the wafer W and the hot plate 51 is exhausted through the intake holes 51V of the hot plate 51, and the pressure in this space is higher than the atmospheric pressure. Also lower. As a result, the wafer W and the hot plate 51 come close to each other while being deformed, and the distance between the wafer W and the hot plate 51 is maintained substantially constant by the spacer 51S, and the entire wafer W is heated uniformly.

  After heating the wafer W at the first temperature for a predetermined period, the exhaust by the exhaust device 60 is stopped, and the lift pins 53 are lifted to lift the wafer W from the hot plate 51 (FIG. 13D). Next, when the cooling plate CP is moved between the wafer W and the hot plate 51 and the lift pins 53 are lowered, the wafer W is received by the cooling plate CP (FIG. 13E). Thereafter, the cooling plate CP moves to the transfer port 24 side, and the wafer W is transferred from the cooling plate CP to the interface arm 67 and unloaded from the heating device 50.

Next, the power supplied from the power source PS to the hot plate 51 is adjusted, and the lift pins 53 and the annular lid member 57 are lifted again (FIG. 13 (f)). Thereby, the space in the chamber 50 </ b> C communicates with the space below the casing 52 through the opening 52 a formed at the bottom of the casing 52. Here, clean gas is supplied from the gas nozzle 54 to the space in the chamber 50, and clean gas is also supplied from the exhaust pipe 52V to the space in the chamber 50 by closing the open / close valve 60a and opening the open / close valve 58a. The clean gas supplied from the gas nozzle 54 and the exhaust pipe 52V is blown to the hot plate 51 to take heat from the hot plate 51 and is exhausted through the opening 52a. Thereby, the space in the chamber 50 is efficiently ventilated, cooling of the hot plate 51 is promoted, and the temperature of the hot plate 51 is quickly changed to the second temperature.
Subsequently, the next wafer W is carried in by the cooling plate CP (see FIG. 12A), and thereafter, in the same manner as described with reference to FIG. 12B to FIG. W is heated at the second temperature and unloaded from the heating device 50.

As described above, also in the substrate heating method according to the fifth embodiment, the wafer W is placed on the hot plate 51 so thin as to be bent by its own weight and curved in a concave shape, via the spacer 51S. Since the space between the two is depressurized by the exhaust device 60 through the intake holes 51V of the hot plate 51, the same effects and advantages as the substrate heating method according to the third embodiment are exhibited. In addition to this, in the substrate heating method according to the fifth embodiment, the lift pins 53 and the annular lid member 57 are lifted, clean gas is supplied from the gas nozzle 54 and the exhaust pipe 52V, and exhausted from the opening 52a of the casing 52. Therefore, the temperature of the hot platen 51 can be changed more quickly.

(Experimental example)
Next, how the wafer W and the hot plate 51 are deformed by depressurizing the space between the wafer W and the hot plate 51 placed on the hot plate 51 via the spacer 51S was examined. The result of the experiment will be described.

In this experiment, a silicon wafer having a diameter of 300 mm and a thickness of 775 μm was used as the wafer W. The size of the hot plate 51 used in the experiment is as follows.
・ Diameter: about 340mm
・ Thickness: about 500μm
・ Inner diameter of intake hole 51V: about 1.1 mm
The height of the spacer 51S from the surface of the hot plate 51: about 100 μm
The distance between the wafer W and the hot plate 51 was measured with a laser displacement meter.

  The measurement results are shown in FIG. Here, FIG. 14A shows a distance between the wafer W and the hot plate 51 when the wafer W is placed on the hot plate 51 via the spacer 51S. From this graph, it can be seen that the wafer W is curved in a convex shape, and the uppermost point is higher by about 250 μm than the lowermost point. On the other hand, the hot platen 51 is not a uniform concave shape, but is curved in a convex shape in a part similar to the wafer W. This is considered to be a result of reflecting the shape of the wafer W due to the influence of static electricity or the like acting between the two when the wafer W is placed on the hot platen 51. Here, although the interval between the wafer W and the hot plate 51 is substantially zero at the periphery of the wafer W, it can be seen that it is about 100 μm in a wide range.

  FIG. 14B shows the distance between the wafer W and the hot plate 51 when the space between the wafer W and the hot plate 51 is depressurized so as to be about 2 kPa lower than the atmospheric pressure. . From this graph, it can be seen that by reducing the space between the wafer W and the hot plate 51, the wafer W and the hot plate 51 are deformed to each other, and the distance between them is reduced. In particular, it can be seen that the distance between them is substantially constant over a wide range of the wafer W. From this, the effect of the substrate heating method by embodiment of this invention is understood.

  As can be seen from the above experimental results, even when the wafer W is curved in a convex shape, the distance between the wafer W and the hot plate 51 can be made substantially constant.

(Modification)
Next, modified examples of the heating devices 50 and 501 described above will be described. Referring to FIG. 15A, an exhaust pipe 51p is connected to the intake hole 51V of the hot plate 51, and the exhaust pipe 51p is connected to an exhaust device (not shown) at the other end. According to this, the space between the wafer W and the hot plate 51 is exhausted through the exhaust pipe 51p and depressurized. Therefore, the heating apparatus according to this modification also exhibits the same effects and advantages as those of the second and fourth embodiments.

  Referring to FIG. 15B, the heating device according to this modification includes an annular lid member 57 </ b> A that is detachably provided on the bottom surface of the casing 52. Unlike the above-described annular lid member 57, the annular lid member 57A is provided separately from the lift pins 53. That is, the through hole corresponding to the three lift pins 53 is formed in the annular lid member 57A, and the lift pins 53 are raised and lowered independently through these through holes. The annular lid member 57A can be lifted and lowered independently of the lift pins 53 by a lifting mechanism (not shown).

According to this configuration, when the temperature of the heat plate 51 is changed from the first temperature to the second temperature (<first temperature), only the annular lid member 57A is lowered, and the gas nozzle 54 and the exhaust pipe 52V are lowered. The clean gas supplied to the space in the chamber 50 </ b> C can be exhausted from the opening 52 a at the bottom of the casing 52. Therefore, the same effects and advantages as those of the fourth and fifth embodiments are exhibited. Further, in this modified example, when the space in the chamber 50 is exhausted through the exhaust pipe 52V by the exhaust device 60 (see FIG. 10), the annular lid member 57A is pressed against the back surface of the bottom portion of the casing 52. This is preferable because the space in the chamber 50 can be easily maintained at a reduced pressure.
In the heating device 501 according to the fourth embodiment, the annular lid member 57 may be provided separately from the lift pins 53, and the annular lid member 57 and the lift pins 53 may be moved up and down independently.

Although the present invention has been described above with reference to some embodiments and modifications, the present invention is not limited to the described embodiments and modifications, and further in light of the description of the appended claims. Changes or modifications are possible.
For example, in the third embodiment, after the wafer W is heated at the first temperature, the wafer W is lifted from the hot plate 51, and the cooling plate CP that has received the wafer W exits, the temperature of the hot plate 51 is changed to the first temperature. The temperature was changed from 1 to the second temperature (<first temperature). However, the temperature of the hot plate 51 may be changed at the same time (or slightly delayed) as the wafer W is heated at the first temperature and the wafer W is lifted from the hot plate 51. Thereby, the change from 1st temperature to 2nd temperature can be completed at an early stage. Of course, when the temperature change is started earlier, the supply of the clean gas from the gas nozzle 54 may be started earlier.

  In the third embodiment, when the temperature of the hot plate 51 is changed from the first temperature to the second temperature (see FIG. 9F), when supplying the clean gas from the gas nozzle 54, The chamber 50C may be exhausted using the exhaust device 60 (FIG. 5). In this way, the space in the chamber 50 can be efficiently ventilated, and thus the cooling of the hot plate 51 can be promoted. In this case, a flow rate controller may be provided in the exhaust pipe 52V, and the exhaust amount may be adjusted in accordance with the total supply amount of clean gas supplied from the gas nozzle 54 into the chamber 50.

  Furthermore, in the fifth embodiment, the cooling plate CP that has received the wafer W is withdrawn, the lift pins 53 and the annular lid member 57 are lifted again, and then a clean gas is supplied from the gas nozzle 54 and the exhaust pipe 52V (FIG. 13). (Refer to (f)). However, it is not necessary to lower the lift pin 53 and the annular lid member 57 once and then lift them. That is, after delivering the wafer W to the cooling plate CP, after lowering the lift pins 53 and the annular lid member 57 so that the annular lid member 57 does not contact the bottom surface of the casing 52, the temperature change of the hot plate 51 is started. Clean gas may be supplied from the gas nozzle 54 and the exhaust pipe 52V.

  Further, the exhaust pipe 52V is not limited to the substantially central portion of the bottom portion of the casing 52, and may be connected to a position shifted from the center of the bottom portion of the casing 52, or may be connected to a side portion of the casing 52.

  In addition, the substrate heating apparatus and the substrate heating method according to the embodiment of the present invention can be applied not only to a semiconductor wafer but also to a glass substrate for FPD.

  DESCRIPTION OF SYMBOLS 100 ... Coating and developing apparatus, S1 ... Carrier station, S2 ... Processing station, S3 ... Interface station, 20 ... Carrier, C ... Conveyance mechanism, U1, U2 ... Shelf unit , B1... First block (DEV layer), B2... Second block (BCT layer), B3... Third block (COT layer), B4. Layer), F ... interface arm, 50 ... heating device, 50C ... chamber, 51 ... hot plate, 51S ... spacer, 52 ... casing, 53 ... lift pin, 54. ..Gas nozzles 54, 51V ... intake holes, 52V ... exhaust pipe, 56 ... gas supply system, 60 ... exhaust device, W ... wafer.

Claims (13)

A heating plate that includes a heating element that heats the substrate and has a flexibility to bend into a concave shape by its own weight when attached at the periphery ; and
A substrate support member provided on the heating plate and supporting the substrate;
A substrate heating apparatus comprising: a decompression unit that decompresses a space between the substrate supported by the substrate support member disposed in the vicinity of the periphery of the heating plate and the curved heating plate. A through hole is provided in the heating plate,
The substrate heating apparatus according to claim 1, wherein the decompression unit decompresses the space through the through hole. It has a cylindrical shape and further has a frame that supports the peripheral part of the heating plate,
The substrate heating apparatus according to claim 2, wherein the decompression unit decompresses the space between the heating plate and the frame, and thereby the space is decompressed through the through hole.   The substrate heating apparatus according to claim 1, further comprising a gas supply unit that supplies gas to the heating plate.   The substrate heating apparatus according to claim 3, further comprising a gas supply unit that passes through the frame and supplies gas to the heating plate.   The substrate heating apparatus according to claim 5, wherein the frame body has an opening at a bottom portion, and the gas supplied from the gas supply unit to the heating plate is exhausted from the opening. A photoresist coating unit for forming a photoresist film on the substrate;
The substrate heating apparatus according to any one of claims 1 to 6, which heats the photoresist film;
A coating and developing apparatus, comprising: a developing unit that develops the photoresist film exposed through a predetermined photomask in an exposure apparatus. A heating plate that includes a heating element for heating the substrate and has a flexibility that curves in a concave shape due to its own weight when mounted at the peripheral portion is placed via a substrate support member provided on the heating plate. And steps to
Depressurizing the space between the substrate supported by the substrate support member disposed in the vicinity of the periphery of the heating plate and the curved heating plate.   The substrate heating method according to claim 8, wherein in the depressurizing step, the space is depressurized through a through hole provided in the heating plate.   In the depressurizing step, the space is depressurized through the through-hole by depressurizing a space between the heating plate and a frame body that has a cylindrical shape and supports a peripheral portion of the heating plate. The substrate heating method according to claim 9.   The substrate heating method according to claim 8, further comprising supplying a gas to the heating plate. In the step of supplying the gas, it has a cylindrical shape, passes through a frame body that supports a peripheral portion of the heating plate, and supplies the gas to the heating plate from the gas supply unit to the heating plate. The substrate heating method according to claim 11 , wherein gas is supplied.   The step of supplying the gas, wherein the gas supplied from the gas supply unit to the heating plate is exhausted from the opening from an opening provided at a bottom of the frame. Substrate heating method.

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