JP3782314B2 - Application processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a coating processing apparatus that applies a resist solution to a substrate such as a semiconductor wafer and performs heat treatment.
[0002]
[Prior art]
For example, in a photolithography process for semiconductor devices, a resist is applied to a semiconductor wafer, a predetermined circuit pattern is exposed to the formed resist film, and this exposure pattern is developed to form a circuit pattern on the resist film. Is done.
[0003]
In general, in such a photolithography process, various heat treatments such as heat treatment after resist application (pre-baking), heat treatment after exposure (post-exposure baking), heat treatment after development (post-baking) and the like are performed. Has been done. Such a resist heat treatment is usually performed by using a hot plate unit in which a heating plate (hot plate) heated by a heater is disposed in a casing.
[0004]
Here, in the pre-bake treatment, various solvents contained in the resist solution are evaporated, thereby forming a resist film. The type of the solvent varies depending on the resist, and there are many types such as those having a low boiling point and a high vapor pressure and those having a high boiling point and a low vapor pressure. Conventionally, these solvent components have been discharged to the outside in the form of being included as steam in the hot exhaust from the hot plate unit. For example, the heat exhaust containing the solvent vapor is sent to a processing apparatus equipped with a scrubber or the like through factory piping in a factory where a coating processing apparatus equipped with a hot plate unit is installed. The solvent component was removed in the apparatus.
[0005]
One reason that such a method could be used is that many solvent components contained in conventional resists have a low boiling point and a high vapor pressure, and even if hot exhaust passes through factory piping. Since the solvent vapor is rarely liquefied by cooling and condensing, the inside of the piping is rarely contaminated.
[0006]
[Problems to be solved by the invention]
However, in recent years, as the integration and performance of semiconductor products are rapidly progressing, the resist used for forming the circuit pattern also dissolves various components adapted to the purpose of use and the components. A variety of solvents are now being used.
[0007]
For example, NMP (normal methyl pyrrolidone) having a high boiling point and a low vapor pressure is used for a polyimide resist, and such a high boiling point component has a temperature of heat exhaust exhausted from a hot plate unit. Condensation does not occur when it is high, but when it is naturally cooled while flowing through the pipe and drops to near normal temperature, condensation may occur inside the pipe, causing the pipe to become clogged, resulting in a problem of reducing the exhaust function. . In this case, there is a problem that the maintenance cost of the factory piping is increased.
[0008]
  The present invention has been made in view of such problems of the prior art, and provides a coating processing apparatus that prevents condensation and condensation in the piping of solvent components in the heat exhaust discharged from the heating apparatus. With the goal.
[0009]
[Means for Solving the Problems]
  That is, according to the present invention, there is provided a coating processing apparatus that applies a predetermined processing liquid to a substrate and then performs a heat treatment,
  A coating processing unit that applies a processing liquid to the substrate, a heating processing unit that heats the substrate coated with the processing liquid, and recovers at least a part of the solvent vapor contained in the heat exhaust discharged from the heating processing unit. A recovery processing unit,
  The recovery processing unit has a cooling device for recovering the solvent vapor by cooling it into a liquid.And
  The cooling device includes a processing chamber that cools and condenses mist and steam from the heat exhaust discharged from the heat treatment unit and separates them as a liquid, an introduction pipe that introduces the heat exhaust into the processing chamber, and a mist in the processing chamber. And a gas passage through which the exhaust gas after the vapor is separated, an exhaust pipe provided in communication with the gas passage for discharging the exhaust gas to the outside, and a liquid condensed in the processing chamber A liquid recovery chamber,
  The exhaust pipe passes through the liquid recovery chamber, and an air inlet for sucking atmospheric gas in the liquid recovery chamber is formed in a part of the exhaust pipe in the liquid recovery chamber.An application processing apparatus is provided.
[0011]
  According to such a coating treatment apparatus of the present invention, the thermal exhaust discharged from the heat treatment unit (heating apparatus) is cooled to a predetermined temperature, and the solvent vapor contained in the thermal exhaust is liquefied and removed. Since it is sent to the factory piping later, dew condensation in the factory piping is suppressed. As a result, the heat treatment can be performed without lowering the exhaust function. In addition, the load required for maintenance of factory piping, etc. is reduced, and corrosion of the factory piping due to solvent vapor or the like is suppressed, and the service life of the factory piping is extended.
[0012]
The removal rate of the solvent vapor can be controlled by the structure, scale, cooling temperature, heat exhaust flow rate, etc. of the installed cooling device, and the recovered solvent can be used as a raw material for reuse. It becomes possible. If a cooling device that circulates inexpensive city water or the like at normal temperature without using a chiller or the like is used, the processing cost can be reduced in terms of both the device cost and the running cost. Further, an apparatus and a method for passing hot exhaust through a demister to liquefy a part of the mist and vapor components contained in the hot exhaust and then passing the hot exhaust through a cooling coil to liquefy the remaining solvent vapor and mist. When is used, the cooling load of the solvent vapor in the cooling coil is reduced, and the service life of the cooling coil can be extended. On the other hand, since the demister is a net-like material, the exchange is easy.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, taking as an example a coating processing apparatus when a resist is applied to a semiconductor wafer (wafer) and then pre-baked. First, an outline of a resist coating / development processing system provided with the coating processing apparatus of the present invention will be given.
[0014]
FIG. 1 is a schematic plan view showing a resist coating / developing system, FIG. 2 is a front view thereof, and FIG. 3 is a rear view thereof. This resist coating / development processing system 1 transfers a wafer W between a cassette station 10 which is a transfer station, a processing station 11 having a plurality of processing units, and an exposure apparatus (not shown) provided adjacent to the processing station 11. And an interface unit 12 for delivery.
[0015]
The cassette station 10 carries a plurality of wafers W as processing objects, for example, in units of 25, into the wafer cassette CR, and carries them into the resist coating / development processing system 1 from the other systems, or This is for carrying the wafer W between the wafer cassette CR and the processing station 11 such as unloading from the coating / development processing system 1 to another system.
[0016]
In the cassette station 10, as shown in FIG. 1, a plurality (four in the figure) of positioning protrusions 20a are formed on the cassette mounting table 20 along the X direction in the figure, and the wafer is positioned at the position of the protrusions 20a. The cassette CR can be placed in a row with the respective wafer entrances facing the processing station 11 side. In the wafer cassette CR, the wafers W are arranged in the vertical direction (Z direction). Further, the cassette station 10 has a wafer transfer mechanism 21 located between the cassette mounting table 20 and the processing station 11.
[0017]
The wafer transfer mechanism 21 has a wafer transfer arm 21a that can move in the cassette arrangement direction (X direction) and the arrangement direction (Z direction) of the wafers W in the cassette arrangement direction. The wafer cassette CR can be selectively accessed. Further, the wafer transfer arm 21a is configured to be rotatable in the θ direction shown in FIG. 1, and a third processing unit G on the processing station 11 side to be described later.₃An alignment unit (ALIM) and an extension unit (EXT) belonging to can be accessed.
[0018]
On the other hand, the processing station 11 includes a plurality of processing units for performing a series of steps when coating / developing is performed on the wafer W, and these are arranged in multiple stages at predetermined positions. Are processed one by one. As shown in FIG. 1, the processing station 11 has a wafer transfer path 22a at the center thereof, in which a main wafer transfer mechanism 22 is provided, and all the processing units are arranged around the wafer transfer path 22a. It is an arranged configuration. The plurality of processing units are divided into a plurality of processing units, and each processing unit has a plurality of processing units arranged in multiple stages along the vertical direction (Z direction).
[0019]
As shown in FIG. 3, the main wafer transfer mechanism 22 is equipped with a wafer transfer device 46 that can move up and down in the vertical direction (Z direction) inside a cylindrical support 49. The cylindrical support 49 can be rotated by a rotational driving force of a motor (not shown), and accordingly, the wafer transfer device 46 can also be rotated integrally. The wafer transfer device 46 includes a plurality of holding members 48 that are movable in the front-rear direction of the transfer base 47, and the transfer of the wafers W between the processing units is realized by these holding members 48.
[0020]
Further, as shown in FIG. 1, in this embodiment, four processing units G₁・ G₂・ G₃・ G₄Are actually arranged around the wafer transfer path 22a, and the fifth processing unit G₅Can be arranged as needed. Of these, the first and second processing units G₁・ G₂Are arranged in parallel on the front side (front side in FIG. 1) of the resist coating / development processing system 1, and the third processing unit G₃Is arranged adjacent to the cassette station 10 and the fourth processing section G₄Is disposed adjacent to the interface unit 12. The fifth processing unit G₅Can be placed on the back.
[0021]
First processing unit G₁In the coater cup (CP), a resist coating unit (COT), which is two spinner type processing units for performing a predetermined process by placing the wafer W on a spin chuck (not shown), and a developing unit (DEV) for developing a resist pattern. ) Are stacked in two steps from the bottom. Second processing unit G₂Similarly, a resist coating unit (COT) and a developing unit (DEV) are stacked in two stages from the bottom as two spinner type processing units.
[0022]
Third processing unit G₃In FIG. 3, oven-type processing units that perform predetermined processing by placing the wafer W on the mounting table SP are stacked in multiple stages. That is, a cooling unit (COL) for performing a cooling process, an adhesion unit (AD) for performing a so-called hydrophobic process for improving the fixability of the resist, an alignment unit (ALIM) for performing alignment, and loading / unloading of the wafer W An extension unit (EXT) to be performed, and four hot plate units (HP) for performing a heat treatment on the wafer W before and after the exposure process and after the development process are stacked in eight stages in order from the bottom. A cooling unit (COL) may be provided instead of the alignment unit (ALIM), and the cooling unit (COL) may have an alignment function.
[0023]
Fourth processing unit G₄The oven-type processing units are stacked in multiple stages. That is, there are a cooling unit (COL), an extension cooling unit (EXTCOL), an extension unit (EXT), a cooling unit (COL), and four hot plate units (HP), which are wafer loading / unloading units equipped with cooling plates. Are stacked in 8 steps in order.
[0024]
On the back side of the main wafer transfer mechanism 22 is a fifth processing unit G.₅Is provided, the fifth processing unit G₅Can move sideways along the guide rail 25 as viewed from the main wafer transfer mechanism 22. Therefore, the fifth processing unit G₅Even in the case where the space is provided, the space is secured by sliding the guide rail 25 along the guide rail 25, so that the maintenance work can be easily performed from the back with respect to the main wafer transfer mechanism 22.
[0025]
The interface unit 12 has the same length as the processing station 11 in the depth direction (X direction). As shown in FIGS. 1 and 2, a portable pickup cassette CR and a stationary buffer cassette BR are arranged in two stages on the front part of the interface part 12, and a peripheral exposure device 23 is arranged on the rear part. A wafer transfer mechanism 24 is disposed at the center. The wafer transfer mechanism 24 has a wafer transfer arm 24a. The wafer transfer arm 24a moves in the X direction and the Z direction, and can access both cassettes CR and BR and the peripheral exposure device 23. Yes.
[0026]
The wafer transfer arm 24 a is rotatable in the θ direction, and the fourth processing unit G of the processing station 11 is used.₄It is also possible to access an extension unit (EXT) belonging to No. 1 and a wafer transfer table (not shown) on the adjacent exposure apparatus side.
[0027]
In the above-described resist coating / development processing system 1, first, in the cassette station 10, the wafer transfer arm 21 a of the wafer transfer mechanism 21 is placed on the wafer cassette CR containing the unprocessed wafers W on the cassette mounting table 20. Access to take out one wafer W, and the third processing unit G₃To the extension unit (EXT).
[0028]
The wafer W is transferred from the extension unit (EXT) to the third processing unit G by the wafer transfer device 46 of the main wafer transfer mechanism 22.₃After being transferred to the alignment unit (ALIM) and aligned, the wafer is transferred to the adhesion processing unit (AD), where a hydrophobic treatment (HMDS treatment) is performed to improve the fixability of the resist. Since this process involves heating, the wafer W is then transferred to the cooling unit (COL) by the wafer transfer device 46 and cooled.
[0029]
Depending on the type of resist used, the wafer W may be directly transferred to the resist coating unit (COT) without performing the HMDS process. For example, a polyimide resist may be used. .
[0030]
The wafer W that has been processed by the adhesion processing unit (AD) and has been cooled by the cooling unit (COL) or the wafer W that has not been processed by the adhesion processing unit (AD) is continuously resisted by the wafer transfer device 46. It is conveyed to a coating unit (COT), where a resist is applied and a coating film is formed. After the coating process, the wafer W is transferred to the third or fourth processing unit G.₃・ G₄Is pre-baked in one of the hot plate units (HP), and then cooled in one of the cooling units (COL).
[0031]
The cooled wafer W is transferred to the third processing unit G.₃After being transferred to the alignment unit (ALIM) and aligned there, the fourth processing unit G₄Are transferred to the interface unit 12 via the extension unit (EXT).
[0032]
The wafer W is subjected to peripheral exposure by the peripheral exposure device 23 in the interface unit 12 to remove excess resist, and then transferred to an exposure device (not shown) provided adjacent to the interface unit 12, where the wafer W is transferred according to a predetermined pattern. An exposure process is performed on the W resist film.
[0033]
The exposed wafer W is returned to the interface unit 12 again, and the fourth processing unit G is processed by the wafer transfer mechanism 24.₄To the extension unit (EXT) belonging to Then, the wafer W is transferred to one of the hot plate units (HP) by the wafer transfer device 46, subjected to post-exposure baking, and then cooled by the cooling unit (COL).
[0034]
Thereafter, the wafer W is transferred to a developing unit (DEV) where the exposure pattern is developed. After the development is completed, the wafer W is transferred to one of the hot plate units (HP), subjected to a post-baking process, and then cooled by a cooling unit (COL). After such a series of processing ends, the third processing unit G₃Is returned to the cassette station 10 via the extension unit (EXT) and accommodated in one of the wafer cassettes CR.
[0035]
Next, the hot plate unit (HP) described above will be described in more detail with reference to the cross-sectional view of FIG.
[0036]
The hot plate unit (HP) has a casing 50, and a heating plate 51 having a disk shape is disposed on the lower side inside the casing 50. The heating plate 51 is made of, for example, aluminum, and a proximity pin 52 is provided on the surface thereof. The wafer W is placed on the proximity pin 52 in a state of being close to the heating plate 51. An electric heater 53 having a predetermined pattern is disposed on the back surface of the heating plate 51.
[0037]
The heating plate 51 is supported by a support member 54, and the support member 54 is hollow. The heating plate 51 is formed with three through holes 55 (only two are shown) at the center thereof, and three elevating pins 56 for raising and lowering the wafer W can be raised and lowered in these through holes 55. Is provided. A cylindrical guide member 57 that is continuous with the through hole 55 is provided between the heating plate 51 and the bottom plate of the support member 54. These guide members 57 can raise and lower the elevating pins 56 without being obstructed by heater wiring or the like under the heating plate 51. These elevating pins 56 are supported by a support plate 58, and are moved up and down by a cylinder 59 provided on the side of the support member 54 via the support plate 58.
[0038]
A support ring 61 that surrounds and supports the heating plate 51 and the support member 54 is provided, and a cover body 62 that is movable up and down is provided on the support ring 61. Then, the heat treatment space S of the wafer W is formed in a state where the lid 62 is lowered to the upper surface of the support ring 61.
[0039]
The lid 62 has a conical shape that gradually increases from the outside toward the center, and has an exhaust port 63 to which an exhaust pipe 64 is connected at the top of the center. The heat treatment space S is exhausted through the pipe 64.
[0040]
In the hot plate unit (HP) configured as described above, first, the wafer W is loaded into the casing 50 in a state where the lid 62 is raised, and the lift pins 56 are on standby in a state where the wafer W is projected. Then, the wafer W is placed, and the lift pins 56 are lowered to place the wafer on the proximity pins 52. Next, the lid body 62 is lowered to heat the wafer W at a predetermined temperature in the heat treatment space S while exhausting the solvent vapor evaporating from the wafer W through the exhaust port 63 and the exhaust pipe 64.
[0041]
Conventionally, the solvent vapor contained in the hot exhaust discharged from the hot plate unit (HP) through the exhaust pipe 64 has been sent to a purification apparatus equipped with a scrubber through a factory pipe or the like and removed. However, the types of processing liquids such as resist liquids used for liquid processing of the wafer W are widespread, and these processing liquids are liquefied (condensed) while passing through the factory pipes and stay in the factory pipes. Substances are also being used. Therefore, in the present invention, a cooling device is disposed between the exhaust pipe 64 and the factory piping, etc., and the hot exhaust discharged from the hot plate unit (HP) through the exhaust pipe 64 is cooled, and the A predetermined amount of the solvent vapor contained is removed and recovered as a liquid.
[0042]
FIG. 5 is an explanatory view showing an embodiment of the cooling device. The cooling device 70 includes a demister 72 that removes mist and the like contained in the heat exhaust, a cooling coil 73 that cools the heat exhaust and liquefies the solvent in the heat exhaust, and a recovery tank 77 that recovers the liquefied solvent and the like. And have.
[0043]
The exhaust pipe 64 of the hot plate unit (HP) is connected to a hole 71a provided on the side wall of the cooling device 70, and in the cooling device 70, the heat exhaust flowing through the exhaust pipe 64 is removed from the processing chamber. The exhaust pipe 71 is disposed so as to pass through the bottom wall of the processing chamber 81 from the hole 71 a toward the processing chamber 81 so that it can be led to the processing chamber 81. The exhaust pipe 71 has a shape that protrudes upward from the bottom wall of the processing chamber 81 and then bends downward, so that liquid falling from the demister 72 or the cooling coil 73 to the bottom wall of the processing chamber 81 is exhausted. It does not flow into the pipe 71.
[0044]
The thermal exhaust discharged from the exhaust pipe 71 to the processing chamber 81 first passes through the demister 72. Here, most of the mist contained in the heat exhaust adheres to the demister 72, and a part of the solvent vapor adheres to the demister 72 and liquefies. Mist or liquefied solvent adhering to the demister 72 falls to the bottom wall of the processing chamber 81 due to its own weight.
[0045]
In this way, the mist and solvent vapor captured by the demister 72 are a part of the mist and solvent vapor contained in the heat exhaust, and thus all the mist and solvent contained in the heat exhaust in the cooling coil 73. There is no need to liquefy the steam, the cooling load on the cooling coil 73 is reduced, and the cooling efficiency can be increased. As the demister 72, for example, a metal mesh having a predetermined opening diameter can be used.
[0046]
The hot exhaust gas that has passed through the demister 72 passes through the cooling coil 73. The cooling coil 73 has a structure in which a refrigerant flows through the pipe, and has a large number of fins formed on the surface so that the surface area of the pipe is increased, a pipe bent in a complicated manner, and a plurality of straight pipes arranged in parallel. Those arranged in the above are preferably used. When the hot exhaust comes into contact with the surfaces of such fins and tubes, the solvent vapor in the hot exhaust is liquefied, and naturally falls by its own weight, and falls to the bottom of the processing chamber 81 together with the amount liquefied in the demister 72.
[0047]
As the refrigerant used for the cooling coil 73, the refrigerant may be liquid (water, oil, etc.) or gas (substitute chlorofluorocarbon etc.) as long as the surface of the tube is cooled. As the temperature of the refrigerant flowing through the cooling coil 73 is lower, the recovery efficiency of the solvent vapor is improved, and it is possible to recover the solvent species having a low boiling point. A heat exchanger such as a chiller may be provided. On the other hand, it is also possible to send industrial water, city water or the like directly to the cooling coil 73 without using a chiller or the like.
[0048]
The temperature and flow rate of the refrigerant sent to the cooling coil 73 are preferably determined in consideration of the type and boiling point of the solvent contained in the heat exhaust to be recovered, the temperature and flow rate of the heat exhaust, and the like. Further, when the temperature of the refrigerant sent to the cooling coil 73 is high, the flow rate is increased. On the other hand, when the temperature of the refrigerant is low, the flow rate is decreased to maintain the necessary cooling capacity in the cooling coil 73. be able to.
[0049]
In the present invention, industrial water or city water is used as the refrigerant, and a coolant having a structure for cooling the surface of the pipe by sending such cooling water using a circulation device such as a pump is preferably used. . Even in a state where the cooling device 70 is not operated, it is preferable that the cooling water is continuously fed at a minimum flow rate and circulated to prevent the generation of bacteria. In the cooling device 70 shown in FIG. 5, an import 78 and an outport 79 for circulating the cooling water through the cooling coil 73 are provided.
[0050]
Exhaust gas that has passed through the cooling coil 73 flows through a passage 82 and an exhaust pipe 83 in the cooling device 70 to a factory pipe 91 connected to the exhaust pipe 83. The factory piping 91 is an example, and may be connected to other disposal processing facilities. Since the exhaust gas that has passed through the cooling coil 73 is cooled by the cooling coil 73, there is almost no case where the temperature further decreases thereafter. Further, by reducing the temperature of the refrigerant flowing through the cooling coil 73 in consideration of the environmental temperature and the outside air temperature at which the factory pipe 91 is disposed, the temperature of the exhaust pipe when the temperature of the factory pipe 91 passes through the cooling coil 73. It is possible to avoid the situation where the temperature is too low.
[0051]
Thus, since the solvent vapor in the exhaust gas not recovered in the cooling device 70 is removed using a scrubber (not shown) provided in the factory pipe 91 as in the prior art, without being liquefied in the factory pipe 91, Clean exhaust can be performed.
[0052]
For example, in pre-baking after resist application using a polyimide resist, NMP (normal methyl pyrrolidone) contained as a solvent in the resist solution evaporates, but since NMP is a liquid at room temperature, The industrial water can be sufficiently recovered as a liquid by sending it to the cooling coil 73 and cooling the heat exhaust to near room temperature without the need to lower the temperature using a cooling device such as a chiller. . In this way, liquefaction stagnation in the factory piping 91 and the like is prevented, the load on maintenance of the factory piping 91 and the like is reduced, and the occurrence of corrosion and the like of the piping members is also suppressed. When using city water or the like, there is an advantage that the running cost can be kept low.
[0053]
As described above, when recovering the solvent such as NMP from the heat exhaust, when the coolant supplied to the cooling coil 73 is circulated without being forcibly cooled by a chiller or the like, the temperature of the coolant is the heat exhaust. It is preferable to monitor the flow rate and temperature of the cooling water so that the temperature does not become higher than a certain temperature due to heat applied from the heat.
[0054]
The mist adhering to the demister 72 or the solvent liquefied in the cooling coil 73 falls to the bottom of the processing chamber 81 due to its own weight, flows into the groove 74, and is stored and collected in the collection tank 77 via the drain 75. The solvent recovered in the recovery tank 77 can be processed and reused. The valve 76 may be normally opened and closed when the recovery tank 77 is replaced, while the groove 76 and the processing chamber 81 are normally closed with the valve 76 closed. When a certain amount of solvent is stored in the bottom of the tank, the valve 76 may be opened to recover the solvent in the recovery tank 77.
[0055]
The solvent vapor leaking from the recovery tank 77 is sucked from an intake port 83 a provided in the exhaust pipe 83 and guided to the factory piping 91. In this way, the atmosphere of the space in which the recovery tank 77 is arranged is kept clean to prevent corrosion and the like of various parts arranged in this space, and the work safety when the recovery tank 77 is replaced is improved. To do.
[0056]
Such a method using the recovery tank 77 is based on the premise that a manual operation of exchanging the recovery tank 77 is performed. However, the recovery tank 77 is used as a method of recovering the solvent liquefied by the demister 72 and the cooling coil 73. The method is not limited. For example, the cooling device 70a shown in FIG. 6 is provided with a water level sensor 93 on the side wall of the processing chamber 81, and with a drain pipe 92 in place of the recovery tank 77. It has the same structure as the cooling device 70.
[0057]
In the cooling device 70a, for example, the valve 76 is always opened, and the solvent or the like that falls from the demister 72 or the cooling coil 73 to the bottom of the processing chamber 81 is always provided outside through the drainage pipe 92 (not shown). It is possible to send the solution to a recovery device, a disposal device or the like and dispose of it. In this case, when the drainage pipe 92 is clogged or the like and the solvent stays in the processing chamber 81, the water level sensor 93 detects the staying of the solvent and issues an alarm. It can be configured to stop or the like.
[0058]
When the valve 76 is normally closed, the solvent falling in the bottom of the processing chamber 81 is stored in the processing chamber 81, and when the water level sensor 93 detects that the solvent has reached a predetermined water level. A structure in which the valve 76 is opened is also possible. Even in this case, the solvent stored in the bottom of the processing chamber 81 can be sent to a collecting device (not shown) or a discarding device provided outside through the drainage pipe 92 and disposed.
[0059]
In the case where the drainage pipe 92 is provided in this way, if liquid is recovered from the drainage pipe 92 to, for example, a large tank, a water level sensor is attached to the large tank to determine whether the solvent can be recovered. Information can be fed back to the control device 93 to a water level sensor attached to the cooling device 70a, and an alarm can be provided so that both the processing chamber 81 and the large tank do not overflow. Thus, when the drainage pipe 92 is provided, automatic operation becomes possible.
[0060]
The above-described cooling devices 70 and 70a can be provided in each of the hot plate units (HP), or several hot plate units (HP) are used only for one process, for example, pre-baking of a resist film. Thus, it is also possible to determine a processing application and arrange one cooling device 70 / 70a for each predetermined processing application. Furthermore, it is also possible to process the heat exhaust from all the hot plate units (HP) with one cooling device 70 / 70a.
[0061]
In the former two cases, the type of solvent vapor in the hot exhaust discharged from the hot plate unit (HP) is constant unless the processing solution such as the resist solution to be used is changed. Can be recovered. On the other hand, in the latter case, the solvent vapor used in various processing solutions such as a resist solution and a developing solution is cooled and condensed together, so that the recovered solvent becomes a mixed solution and the purity is low. There is an advantage that the device structure is simplified and maintenance is easy.
[0062]
FIG. 7 is an explanatory diagram showing an example of the arrangement of the cooling device 70 as an example. The third processing unit G₃And the fourth processing unit G₄The structure which exhausts the heat exhaust_gas | exhaustion discharged | emitted from all the hotplate units (HP) arrange | positioned in (1) to the factory piping 91 through the one cooling device 70 is shown. In FIG. 7, the detailed structure of the cooling device 70 is not shown.
[0063]
The cooling device 70 can be appropriately disposed at a suitable position corresponding to the position where the resist coating / development processing system is disposed. For example, the cooling device 70 can be installed on the same floor where the resist coating / development processing system is installed, as in the installation location A shown in FIG. It is also possible to install it below the floor where the coating / developing system is provided. These installation locations A and B do not cause a difference in the cooling performance of the heat exhaust in the cooling device 70 and the NMP recovery efficiency.
[0064]
Third processing unit G₃The exhaust pipes 64 of the four hot plate units (HP) arranged in one are connected to one exhaust pipe 65, and similarly, the fourth processing section G₄Each of the exhaust pipes 64 of the four hot plate units (HPs) disposed in is connected to one exhaust pipe 66. The exhaust pipes 65 and 66 are connected to the joint box 67, and the heat exhaust from the exhaust pipes 65 and 66 merges in the joint box 67. An exhaust pipe 68 is provided between the joint box 67 and the cooling device 70, and the thermal exhaust discharged from the hot plate unit (HP) through the exhaust pipe 68 is sent to the cooling device 70.
[0065]
As the exhaust pipes 65 and 66, for example, those having an inner diameter of 75 mmφ are used, and as the exhaust pipe 68, for example, those having an inner diameter of 100 mmφ are used. The lengths of the exhaust pipes 65, 66 and 68 are preferably 3 m or less for the exhaust pipes 65 and 66 and 10 m or less for the exhaust pipe 68 so that the pressure loss does not increase.
[0066]
For the cooling device 70, the temperature of the cooling water sent to the cooling coil 73 is in the range of 15 degrees (° C.) to 23 ° C., and the heat exhaust flow rate blown into the cooling device 70 is 3 m.³/ Min or less. At this time, when the temperature of the heat exhaust flowing into the cooling device 70 is 40 ° C., the cooling capacity of the cooling device 70 is adjusted so that the temperature of the exhaust discharged from the cooling device 70 is 25 ° C. or less. It is preferable. By setting such conditions, it is possible to sufficiently remove NMP from the hot exhaust.
[0067]
FIG. 8 is an explanatory diagram showing an example of the cooling performance of the cooling device 70, where the temperature of the hot exhaust gas flowing into the cooling device 70 is 40 ° C., and the temperature of the cooling water sent to the cooling coil 73 is shown. When the flow rate is 21 liters and the flow rate is 3 liters / minute, the relationship between the heat exhaust flow rate flowing into the cooling device 70 and the temperature of the exhaust discharged from the cooling device 70 and the heat exhaust flow rate flowing into the cooling device 70 The relationship with the temperature of the cooling water discharged | emitted from the cooling coil 73 is shown. In addition, the environmental temperature in the place where the cooling device 70 is disposed was 23 ° C.
[0068]
As shown in FIG. 8, the temperature change of the cooling water discharged from the cooling coil 73 is larger than the temperature change of the exhaust discharged from the cooling device 70, and the flow rate of the heat exhaust gas flowing into the cooling device 70 changes. However, the temperature change of the exhaust discharged from the cooling device 70 is small. That is, in the cooling device 70, sufficient heat exchange is performed for the heat exhaust flowing into the cooling device 70. By using the cooling device 70 having such a cooling performance, most of the vapor of the solvent such as NMP contained in the hot exhaust can be separated and removed by the cooling device 70.
[0069]
In the above description, NMP is exemplified as the solvent, but the solvent may be IPA, pure water, or the like. That is, various solvents such as a solvent such as thinner applied to the wafer W before the resist solution is applied to the wafer W, and a cleaning solution such as pure water and IPA used for washing away the developer used for the development processing after the exposure processing. Also for the heat exhaust containing the solvent vapor, the cooling devices 70 and 70a are provided to cool the heat exhaust, liquefy and separate the solvent vapor, and the exhaust with reduced solvent vapor amount is supplied to the factory piping 91. It is possible to prevent long-term maintenance by suppressing corrosion of the factory piping 91 and the like. Further, even when the heat exhaust discharged from the hot plate unit (HP) contains a component that is difficult to be liquefied in the factory piping 91, the above-described cooling devices 70 and 70a can be disposed. . In this way, it becomes possible to recover the solvent that has been discarded in the past as a resource.
[0070]
The arrangement positions of the cooling devices 70 and 70a are not limited to the positions shown in FIG. For example, FIG. 9 is a plan view of the resist coating / development processing system 1 described above, and a part of FIG. 1 is simplified, but the cooling devices 70 and 70a are replaced with, for example, a fifth process. Part G₅When not provided (see FIG. 1), the fifth processing unit G₅It can be provided in the position. Further, as shown in the plan view of FIG. 10, in the resist coating / development processing system 1, third and fourth processing units G in which hot plate units (HP) are disposed are provided.₃・ G₄It is also possible to provide it closely behind each of the.
[0071]
Further, in FIG. 7 described above, the cooling device 70 is separately provided on the outside of the back surface of the resist coating / development processing system 1 or the like. However, there is a restriction on the arrangement space of the cooling devices 70 and 70a. 11 has a structure in which an exhaust pipe 71 ′ communicating with the exhaust pipe 64 and an exhaust pipe 83 ′ communicating with the factory pipe 91 are attached to the bottom wall of the cooling apparatus 70 b as in the cooling apparatus 70 b shown in FIG. 11. The cooling device 70b can be provided in close contact with the side wall of the resist coating / developing system 1 by using a device.
[0072]
When the cooling device 70b is used, the exhaust pipe 64 is taken out from the bottom wall of the resist coating / development processing system 1 toward the floor surface 94 and attached to the bottom wall of the cooling device 70b, and the exhaust pipe 64, the exhaust pipe 71 ', , And the hot exhaust is sent to the processing chamber 81. Further, a factory pipe 91 is attached to the bottom wall of the cooling device 70b to communicate with the exhaust pipe 83 ′, and the exhaust gas that has passed through the cooling coil 73 is guided to the factory pipe 91 through the exhaust pipe 83 ′.
[0073]
When the cooling device 70b is used, the resist coating / development processing system 1 and the cooling device 70b can be arranged in close contact with each other, and the arrangement space of the device can be used effectively. However, when the cooling device 70b is used, the exhaust pipe 64 needs to be folded back, so that the pressure loss is larger than in the case of the cooling devices 70 and 70a. There is a possibility that the liquefied solvent vapor contained therein will remain. For this reason, when it is indispensable to reduce the pressure loss and prevent the solvent from staying in the exhaust pipe 64, use a structure that connects the exhaust pipe 64 to the side wall of the apparatus, such as the cooling devices 70 and 70a. Is preferred.
[0074]
  As described above, the coating processing apparatus of the present invention has been described by taking an example of an apparatus for performing resist coating processing and drying processing on a semiconductor wafer. However, in the present invention, the processing liquid and the solvent contained in the processing liquid are evaporated by the drying. It can be widely applied to apparatuses, for example, an apparatus that performs resist coating and pre-bake processing on an LCD substrate, an apparatus that cleans various substrates and performs drying with an organic solvent such as IPA, and develops and develops various substrates. It can also be used for an apparatus for performing washing and drying after treatment.
[0075]
【The invention's effect】
  According to the coating treatment apparatus of the present invention, the heat exhaust discharged from the heat treatment unit (heating device) is cooled to a predetermined temperature, and the solvent vapor contained in the heat exhaust is liquefied and removed before the factory piping. Therefore, dew condensation in the factory piping is suppressed. This makes it possible to carry out heat treatment without deteriorating the exhaust function, reduce the load on maintenance of factory piping, etc., and suppress the corrosion of factory piping due to solvent vapor etc. An excellent effect of extending the life is obtained. The removal rate of the solvent vapor can be controlled by the structure, scale, cooling temperature, heat exhaust flow rate, etc. of the installed cooling device, and the recovered solvent can be used as a raw material for reuse. The effect that it becomes possible is also acquired. In addition, if a cooling device that circulates inexpensive city water or the like at normal temperature without using a chiller or the like is used, an effect of reducing the processing cost in terms of both the device cost and the running cost can be obtained. Further, the apparatus and method for first passing the heat exhaust through the demister to liquefy part of the mist and vapor components contained in the heat exhaust, and then passing the heat exhaust through the cooling coil to liquefy the remaining solvent vapor and mist. When is used, the cooling load of the solvent vapor in the cooling coil is reduced, and it is possible to extend the service life of the cooling coil.
[Brief description of the drawings]
FIG. 1 is a plan view showing a schematic configuration of an embodiment of a resist coating / developing system according to a coating processing apparatus of the present invention.
FIG. 2 is a front view showing a schematic configuration of an embodiment of a resist coating / developing system according to the coating processing apparatus of the present invention.
FIG. 3 is a rear view showing a schematic configuration of an embodiment of a resist coating / developing system according to the coating processing apparatus of the present invention.
FIG. 4 is a cross-sectional view showing an embodiment of a hot plate unit used in the resist coating / developing system according to the coating processing apparatus of the present invention.
FIG. 5 is a cross-sectional view showing an embodiment of a cooling device used in the resist coating / developing system according to the coating processing apparatus of the present invention.
FIG. 6 is a cross-sectional view showing another embodiment of a cooling device used in the resist coating / developing system according to the coating processing apparatus of the present invention.
FIG. 7 is a plan view showing one form of the arrangement position of the cooling device.
FIG. 8 is an explanatory diagram showing an example of the cooling performance of the cooling device arranged at the position shown in FIG.
FIG. 9 is a plan view showing another embodiment of the arrangement position of the cooling device.
FIG. 10 is a plan view showing still another embodiment of the arrangement position of the cooling device.
FIG. 11 is a cross-sectional view showing still another embodiment of the cooling device.
[Explanation of symbols]
50; casing
51; heating plate
52; Proximity pins
53; Electric heater
54; Support member
62; lid
64; exhaust pipe
70, 70a, 70b; cooling device
71, 71 '; exhaust pipe
72; Demister
73; Cooling coil
74; groove
77; Collection tank
78; Import
79; Outport
81; processing chamber
82; passage
83, 83 '; exhaust pipe
83a; inlet
91; Factory piping
92; drainage pipe
93; Water level sensor
HP: Hot plate unit

Claims (12)

A coating processing apparatus that applies a predetermined processing liquid to a substrate and then performs a heat treatment,
A coating processing unit for applying a processing liquid to a substrate;
A heat treatment unit for heating the substrate coated with the treatment liquid;
A recovery processing unit for recovering at least a part of the solvent vapor contained in the thermal exhaust discharged from the heat processing unit;
Comprising
The recovery processing unit, have a cooling device for recovering the solvent vapor allowed to cool liquefied,
The cooling device is
A processing chamber for cooling and condensing mist and steam from the heat exhaust discharged from the heat treatment unit and separating them as a liquid;
An introduction pipe for introducing heat exhaust into the processing chamber;
A gas passage through which exhaust gas after mist and vapor are separated in the processing chamber flows;
An exhaust pipe provided in communication with the gas passage for discharging exhaust gas to the outside;
A liquid recovery chamber for recovering the liquid condensed in the processing chamber;
Have
The exhaust pipe passes through the liquid recovery chamber, and an air inlet for sucking atmospheric gas in the liquid recovery chamber is formed in a part of the exhaust pipe in the liquid recovery chamber. apparatus. The coating apparatus according to claim 1 , wherein the introduction pipe has a shape that protrudes upward from the bottom of the processing chamber and then bends downward so that hot exhaust is discharged substantially downward. The hot exhaust from the heating part, the coating apparatus according to claim 1 or claim 2, characterized in that it is introduced from a side wall of the cooling device to the cooling device inside. The hot exhaust from the heating part, the coating apparatus according to any one of claims 1 to 3, characterized in that it is introduced from the bottom wall of the cooling device to the cooling device inside. Coating treatment apparatus according to any one of claims 1 to 4, wherein a water level sensor for detecting the liquid amount of the processing chamber to the processing chamber is disposed. The liquid recovery chamber includes a drain provided through the bottom wall of the processing chamber, a drain opening / closing valve provided in the middle of the drain, and a detachable liquid recovery tank attached to the drain. coating treatment apparatus according to any one of claims 1 to 5, characterized in that it has. The recovery processing unit includes a device for processing or recovering waste liquid provided outside the cooling device , and the liquid recovery chamber has a drain provided through the bottom wall of the processing chamber. , coating treatment apparatus according to the recovered liquid any one of claims 1 to 5, characterized in that it is sent to a device for processing or recovering the waste liquid through the drain in the processing chamber. The cooling device includes a demister that mainly removes mist contained in the hot exhaust and a cooling coil that cools, condenses, and liquefies the steam contained in the hot exhaust. Item 8. The coating treatment apparatus according to any one of Item 7 . The coating treatment apparatus according to claim 8 , wherein the demister and the cooling coil are arranged so that hot exhaust gas introduced into the cooling device passes through the cooling coil after passing through the demister. The cooling coil coating apparatus according to claim 8 or claim 9, characterized in that water is used as coolant. The coating processing apparatus according to any one of claims 8 to 10 , wherein the cooling coil uses a refrigerant cooled by a chiller. The cooling coil coating processing apparatus according to claim 10 or claim 11, characterized by using circulating water that is cooled by the chiller.

Images