CN102468200A - Heat treatment device - Google Patents

Abstract

The invention provides a heat treatment apparatus. Which shortens the heat treatment time and saves the heating power in the heat treatment of the glass substrate. A plurality of lower surface body-shaped heaters arranged below a conveying path for conveying a substrate in a horizontal direction are divided into an E row in the central part of the conveying path in the width direction, and a D row and an F row at the two ends. The heating power at the central portion is set higher than the heating power at the both end portions. The column of the lower surface body-shaped heater maintains the temperature corresponding to the heating of the tubular heater, and maintains the temperature to approximately a half region of the space by heat conduction. The heat of the tubular heaters of the column (D, F) is also maintained to a temperature of approximately half the area of the space by heat conduction. Since the tubular heater has low electric power, the temperature is only (Dh, Fh), but the accumulated heat in the inner wall of the housing is integrated with the heat of (Dh, Fh) to reach the same temperature as (Eh).

Description

Heat treatment device

technical field

The present invention relates to a heat treatment apparatus for performing heat treatment on a substrate such as a glass substrate for a flat panel display (FPD).

Background technique

Typically, flat panel displays (FPDs) are fabricated using photolithographic processes. The photolithography process of FPD has three steps: a coating process of coating a resist on a glass substrate, an exposure process of transferring a pattern of a photomask onto a resist film, and a development process of developing a pattern after exposure. basic process. Before and after these basic steps, various heat treatment steps are performed as an auxiliary. For example, heat treatment (dehydration baking) for removing moisture from the substrate is performed before the coating process. Between the application process and the exposure process, heat treatment (pre-baking) for evaporating residual solvent is performed after application of the resist film. After the development step, heat treatment (post-baking) for evaporating and removing the developing solution and cleaning solution remaining in the resist pattern is performed.

Conventional heat treatment (baking) equipment has a hot plate oven structure in many cases. A glass substrate or the like is placed on a hot plate, and a chamber is formed by closing a lid from above, and the substrate is heated in the chamber. , to discharge solvents such as thinner volatilized from the resist film. In the heat treatment apparatus of this form, in order to transfer the substrate to the transfer robot, a lift pin mechanism is included to raise and lower the substrate by raising and lowering a plurality of lift pins from the through holes of the hot plate, and the lid is placed on the hot plate or the lid is turned upward. Open the lid opening and closing mechanism. Alternatively, a device of the type in which the upper cover is fixed and the substrate inlet and outlet is provided on one side wall includes a shutter mechanism for opening and closing the substrate inlet and outlet (for example, refer to Patent Documents 1 and 2).

Patent Document 1: Japanese Patent Application Laid-Open No. 8-313855

Patent Document 2: Japanese Patent Application Laid-Open No. 11-204428

However, in the conventional heat treatment apparatus, there are problems in that it takes a long time to load and unload substrates due to the process of raising and lowering the lift pins and handing over the substrates by the conveyance robot, resulting in low productivity. In addition, in recent years, due to the increase in the size of FPDs, huge glass substrates with a side of more than 2m have appeared. The impact at the time of handover will cause damage and generate particles. In addition, the heating plate generally has poor temperature responsiveness and is maintained at a predetermined temperature. Therefore, in the above-mentioned conventional heat treatment apparatus, it takes a relatively long time from when the glass substrate is placed on the heating plate to reaching the set temperature. time, therefore, it is possible to consume more power.

Contents of the invention

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide a heat treatment apparatus capable of increasing the processing speed without damaging the substrate even for a large glass substrate, reducing particles and saving energy.

In order to solve the above problems, the present invention provides a heat treatment device, which is used for heat treatment of the substrate, characterized in that the heat treatment device includes: a transport path, which is used to transport the substrate in the horizontal direction; a frame, It is installed in a manner to surround the above-mentioned conveying path, and an exhaust mechanism for internal exhaust is provided at the central part of the conveying direction of the above-mentioned substrate and at both ends of the conveying direction; The upper portion of the transport path is provided with a plurality of lower planar heating units, and a plurality of lower planar heating units are arranged at the lower part of the transport route; any one or both of the upper planar heating unit and the lower planar heating unit are arranged. Divided in the conveying direction of the conveying path; at least the lower planar heating part of the upper planar heating part and the lower planar heating part is divided into a central part and both ends in the width direction of the conveying path; The heat treatment device is formed so that the temperature of the above-mentioned both ends can be controlled to be lower than the temperature of the divided above-mentioned central part by the control device.

In the present invention, it is preferable that at least one of the upper planar heating unit and the lower planar heating unit includes a planar radiator and a tubular heater embedded in the radiator. In this case, it is preferable to embed a first tubular heater in the central portion of the planar heating portion in the width direction, and to embed a second tubular heater and a third tubular heater on both sides of the planar heating portion in the width direction. device, the above-mentioned second tubular heater and the third tubular heater are the same type of tubular heater, more preferably the end of the first tubular heater and the end of the second tubular heater, the first tubular heater The end of the pipe heater is separated from the end of the third tubular heater by a predetermined distance in the width direction of the above-mentioned conveying path. In this case, it is preferable that the first tubular heater is a jacket heater, and the second tubular heater and the third tubular heater are cassette heaters.

In addition, in the present invention, it is preferable that at least a part of the wall portion of the frame body has a double-wall structure including an inner wall and an outer wall provided with a space therebetween, and the space between the inner wall and the outer wall acts as a mechanism for separating the frame. The function of the thermal insulation layer composed of thermal insulation material and air for internal and external thermal insulation.

In addition, in the present invention, it is preferable that the above-mentioned planar heat dissipation body includes: a surface, which faces the substrate to be heat-treated; a back surface, which is the surface of the planar heat dissipation body opposite to the surface; A notch, which is continuous from the back, is provided in the region between the above-mentioned separated ends.

In order to solve the above problems, the present invention provides a heat treatment device, which is used for heat treatment of the substrate, characterized in that the heat treatment device includes: a transport path, which is used to transport the substrate in the horizontal direction; a frame, It is installed in a manner to surround the above-mentioned conveying path, and an exhaust mechanism for internal exhaust is provided at the central part of the conveying direction of the above-mentioned substrate and at both ends of the conveying direction; There are a plurality of upper portions of the conveying path; a plurality of lower surface-shaped heating parts are arranged in the lower part of the conveying path; the upper planar heating part and the lower planar heating part are divided in the conveying direction of the conveying path; The above-mentioned upper surface-shaped heating part and the lower surface-shaped heating part are divided into a central part and two end parts in the width direction of the above-mentioned conveying path; The insides of the end portions each have heaters for heating; the temperature of the heaters in the central portion is set to a higher temperature than the heaters in the two end portions.

In addition, in the present invention, it is preferable to set the temperature of the heater at the central portion to be higher than the temperature of the heaters at the both ends by a predetermined value so that the heat accumulated in the frame is conducted to the both ends. On the other hand, the temperature of the above-mentioned both ends and the temperature of the said center part become the same temperature.

According to the present invention, in the heating unit, the conveyance path for conveying the substrate in the horizontal direction, the frame provided to surround the conveyance path, and the conveyance path between the conveyance path and the width direction of the conveyance path The upper and lower parts of the path are divided by arranging a plurality of planar heating parts, and the temperature is controlled for each divided area, whereby the substrate can be heated with high productivity and high uniformity.

In addition, an exhaust mechanism for exhausting air in the above-mentioned frame is provided at the central part and both ends of the conveying direction of the above-mentioned frame, and the heating part at the upper part and the heating part at the lower part make the width direction of the above-mentioned conveying path The heating power is set to be lower in both side portions than in the central portion in the width direction of the conveyance path, whereby heat treatment can be performed with higher uniformity.

Description of drawings

Fig. 1 is a schematic plan view showing a coating-developing device of the present invention.

(a) and (b) of FIG. 2 are cross-sectional views in the planar direction of the lower part of the heat treatment apparatus of the present invention.

Fig. 3 is a cross-sectional view in the side direction of the heat treatment apparatus of the present invention.

Fig. 4 is a plan view showing a part of the lower planar heater of the present invention in cross section.

Fig. 5 is a plan view showing a section of a part of the upper surface heater of the present invention.

Fig. 6 is a schematic diagram of temperature control of the widthwise division of the lower planar heater according to the present invention.

(a) of FIG. 7 is a schematic sectional view of the lower surface heater of the present invention, (b) of FIG. 7 is a distribution diagram of heating power applied to the lower surface heater, and (c) of FIG. Temperature distribution diagram of a planar heater.

Fig. 8 is a top view showing notches provided in the radiator according to the present invention.

Fig. 9 is a plan view showing another form of the notch provided in the radiator according to the present invention.

Fig. 10 is a plan view showing another form of the notch provided in the radiator according to the present invention.

Detailed ways

Next, a case where the heat treatment apparatus of the present invention is applied to a resist coating-development treatment apparatus for an FPD substrate will be described.

FIG. 1 shows a coating-development processing system as an example of the configuration of a heat processing apparatus to which the present invention can be applied. The coating-development processing system 200 is installed in a clean room, for example, an FPD substrate is used as a substrate to be processed (hereinafter referred to as substrate G), and cleaning, resist coating, pre-processing, etc. Various processes such as baking, developing, and post-baking.

The coating-development processing system 200 is generally composed of four zones. It includes a cassette station (C/S) 201 that transfers a cassette C for storing a substrate G to an external device, a coating line portion 202 that applies a chemical solution to a substrate G, and a transfer line that transfers a substrate to an exposure device. An interface (I/F) 203, and a developing line part 205 for developing the substrate G after exposure. The exposure device 204 is provided adjacent to the transition part 203 .

The cassette station section (C/S) 201 includes a cassette mounting table 10 and a transport mechanism 11. The cassette mounting table 10 can place up to four cassettes C side by side in the horizontal direction, for example, in the X direction. G is stacked in multiple layers and stored in multiple sheets; the conveyance mechanism 11 is used to access the substrate G with respect to the cassette C of the cassette mounting table 10 .

The conveyance mechanism 11 has a member capable of holding the substrate G, such as a conveyance arm 12, which can move on the four axes of the horizontal X and Y directions, the vertical Z direction, and the horizontal rotation (θ). The coating production line 202 and the development production line 205 deliver the substrate G.

In the coating line 202, an excimer UV irradiation unit (e-UV) 21, an erasing cleaning unit (S CR) 22, a preheating unit (PH) are arranged in sequence from the box station part 201 toward the transfer part 203. 23. Attachment unit (AD) 24, cooling unit (COL) 25, resist coating unit (CT) 26, decompression drying unit (DP) 27, heat treatment unit (HT) 28, cooling unit (COL) 29 .

The excimer UV irradiation unit (e-UV) 21 performs removal processing of organic substances contained in the substrate G, and the erasing cleaning unit (SCR) 22 performs erasing cleaning processing and drying processing on the substrate G. The preheating unit (PH) 23 heats the substrate G, the attachment unit (AD) 24 performs hydrophobization treatment on the substrate, and the cooling unit (COL) 25 cools the substrate G. The resist coating unit (CT) 26 supplies a resist liquid onto the substrate G to form a resist film, and the decompression drying unit (DP) 27 makes the resist film contained on the substrate G under reduced pressure conditions. The volatile components evaporate to dry the resist film. A heat treatment unit (HT) 28 described later in detail heat-processes the substrate G, and a cooling unit (COL) 29 cools the substrate G similarly to the cooling unit (COL) 25 .

In the development production line 205 , a development unit (DEV) 30 , a heat treatment unit (HT) 31 , and a cooling unit (COL) 32 are arranged sequentially from the transfer portion 203 toward the box station portion 201 . In addition, between the cooling unit (COL) 32 and the cassette station part 201, an inspection device (IP) 35 for performing a series of processes including resist coating and development is provided. The substrate G is inspected.

The developing unit (DEV) 30 performs a process of applying a developer to the substrate G, a process of rinsing the substrate G, and a process of drying the substrate G in this order. The heat treatment unit (HT) 31 heat-processes the substrate G similarly to the heat treatment unit (HT) 28 , and the cooling unit (COL) 32 cools the substrate G similarly to the cooling unit (COL) 25 .

The transfer unit 203 includes a rotary table (RS) 44 serving as a delivery unit for the substrate G on which a buffer box capable of accommodating the substrate G is arranged, receives the substrate G conveyed from the coating line 202 and conveys the substrate G Transfer arm 43 to rotary table (RS) 44. The transport arm 43 can move on the four axes of the horizontal X and Y directions, the vertical Z direction, and the horizontal rotation (θ), and it can also enter the exposure device 204 provided adjacent to the transport arm 43, and the transport arm 43. Arm 43 , developer unit (DEV) 30 are arranged adjacently in external device area 90 with peripheral exposure device (EE) and code generator (TITLER).

The coating-development processing system 200 is connected to the control device 101 and controlled by the control device 101 . The input and output unit 102 and the storage unit 103 are connected to the control device 101. The input and output unit 102 includes a keyboard for the operator to input commands for each part or each unit of the coating-developing processing system 200, and is used to control each part. or a display for monitoring the operation status of each unit, the above-mentioned storage unit 103 is used to store a control program, a process program in which processing condition data, etc. are recorded, and the control program, processing condition data, etc. Various treatments such as heating treatment and cooling treatment performed by the coating-development treatment system 200 are realized.

If necessary, an arbitrary process program can be called from the storage unit 103 by an instruction from the input and output unit 102 and executed by the control device 101, so that the target process can be performed in the coating-development processing system 200 under the control of the control device 101 . In addition, process programs such as control programs and processing condition data can also use data stored in computer-readable storage media such as CD-ROMs, hard disks, flash memory, etc., or can also be obtained from other devices, such as through dedicated The line is transmitted at any time and used online.

In the coating-development processing system 200 configured in this way, first, the substrate G in the cassette C placed on the mounting table 10 of the cassette station section 201 is transported to the coating line 202 by the transport arm 12 of the transport device 11. The upstream end of the substrate G is dry-cleaned by ultraviolet irradiation in the excimer UV irradiation unit (e-UV) 21 . In this ultraviolet cleaning, organic substances on the surface of the substrate are mainly removed. After the ultraviolet cleaning is finished, the substrate G is transferred to the scrub cleaning unit (SCR) 22 of the cleaning process section by roller conveyance.

In the wiping and cleaning unit (SCR) 22, the upper surface (surface to be processed) of the substrate G is subjected to brushing cleaning and blow cleaning while being advected in a horizontal posture by roller conveyance, Thus, particulate dirt is removed from the surface of the substrate. In addition, after washing, the substrate G is blown off with a blower or the like while conveying the substrate G advectively, and the substrate G is dried. In the preheating unit (PH) 23 , the substrate G cleaned in the erasing and cleaning unit (SCR) 22 is heated and dehydrated. In the attachment unit (AD) 24 , hydrophobization treatment is performed on the substrate G that has been heat-treated in the preheating unit (PH) 23 . The adhesion between the substrate G and the resist solution is improved by hydrophobization treatment. In the cooling unit (COL) 25 , the substrate G that has undergone the hydrophobization treatment in the attachment unit (AD) 24 is cooled to a constant normal temperature.

A resist film is formed on the substrate G cooled in the cooling unit (COL) 25 in the resist coating unit (CT) 26 . A resist solution is applied to the substrate upper surface (surface to be processed) of the substrate G by spin coating or slit coating. The substrate G on which the resist film is formed in the resist coating unit (CT) 26 is transported on the transport line, and the resist film is dried in a reduced pressure atmosphere in the reduced pressure drying unit (DP) 27 .

In addition, in the case where the resist coating unit (CT) 26 employs the spin coating method, each of the reference numeral 26i on the upstream side and the reference numeral 26o on the downstream side of the resist coating unit (CT) 26 are only Roller conveying mechanism for conveying substrate G. In addition, when the resist coating unit (CT) 26 adopts the slit coating method, the reference numeral 26i on the upstream side of the resist coating unit (CT) 26 is that of the self-cooling unit (COL) 25. The transfer unit that transfers from the roller conveying mechanism to the conveying mechanism that performs conveyance by air flotation used in the case of slot coating, and the reference numeral 26o on the downstream side is from the conveyance mechanism that performs conveyance by air flotation to the conveyance unit that conveys by air flotation. The transfer unit that performs transfer by the roller conveying mechanism of the decompression drying unit (DP) 27.

In the transport line, the substrate G subjected to the drying process of the resist film in the depressurized drying unit (DP) 27 is transported, and the heat treatment unit (HT) 28 evaporates and removes the residue of the resist film by heat treatment. Contains solvents. The heat treatment is carried out while being conveyed on a conveying line by a roller conveying mechanism 5 described later. The detailed operation of the heat treatment unit (HT) 28 of the present invention will be described later.

The substrate G that has been heat-treated in the heat treatment unit (HT) 28 is transported on the transport line, and cooled in the cooling unit (COL) 29 . After the substrate G cooled in the cooling unit (COL) 29 is transported to the downstream end in the coating line, it is transported to the rotary table (RS) 44 by the transport arm 43 of the transfer unit 203 . Next, the substrate G is transported by the transport arm 43 to the peripheral exposure device (EE) of the external device area 90, and an exposure process for removing unnecessary peripheral portions of the resist film is performed in the peripheral exposure device (EE).

Next, the substrate G is transported to the exposure device 204 by the transport arm 43, and exposure processing of a predetermined pattern is performed on the resist film. In addition, the substrate G may be transported to the exposure device 204 after being temporarily accommodated in a buffer box on the rotary table (RS) 44 . Use the conveying arm 43 to transport the exposed substrate G to the code generator (TITLER) in the external device area 90, and record the ID information of the product in the code generator (TITLER) with two-dimensional code and OCR characters for the specified information.

The substrate G on which predetermined information is recorded in the tag generator (TITLER) is conveyed in the developing line 205, and the developing unit (DEV) 30 is sequentially subjected to a developer application process, rinse process, and drying process. The developer application process, rinsing process, and drying process are performed in such a sequence that, for example, while the substrate G is being transported on the transport line, the developer is deposited on the substrate G, and then the transport is temporarily stopped, and the substrate is tilted at a predetermined angle for development. In this state, the rinse liquid is supplied onto the substrate G to wash off the developing solution, and then the drying gas is sprayed onto the substrate G while the substrate G is returned to a horizontal posture and transported again.

The substrate G that has been treated with the developer in the developing unit (DEV) 30 is transported on the transport line, and heat-treated in the heat treatment unit (HT) 31 to evaporate and remove the solvent contained in the resist film. and moisture. The heat treatment is performed while being conveyed on the conveying line by the roller conveying mechanism 5 . In addition, an i-line UV irradiation unit for decolorizing the developer may be provided between the developing unit (DEV) 30 and the heat treatment unit (HT) 31 . The substrate G that has been heat-treated in the heat treatment unit (HT) 31 is conveyed on the development line 205 and cooled in the cooling unit (COL) 32 .

The substrate G cooled in the cooling unit (COL) 32 is conveyed on the developing line 205 and inspected in the inspection device (IP) 35 . The substrate G that has passed the inspection is accommodated in a predetermined cassette C placed on the stage 10 by the transfer arm 12 of the transfer device 11 provided in the cassette station section 201 .

Next, heat treatment of the substrate G performed in the heat treatment units (HT) 28 and 31 configured as described above will be described with reference to FIG. 3 . In the heat treatment unit (HT) 28, the substrate G conveyed from the decompression drying unit (DP) 27 side is handed over to the roller conveying mechanism 5 when passing through the substrate input port 61, and is conveyed by the roller conveying mechanism 5 while using The upper surface-shaped heater 81 and the lower surface-shaped heater 71 whose temperature is controlled by the hot plate controller 104 are heated in the frame body 6, and in the heat treatment unit (HT) 31, the product transported from the developing unit (DEV) 30 side is heated. When the substrate G passes through the substrate input port 61, it is handed over to the roller conveying mechanism 5, and while being conveyed by the roller conveying mechanism 5, the upper planar heater 81 and the lower planar heater 71 whose temperature is controlled by the hot plate controller 104 Heating inside the frame 6.

In this way, since the conveyance and heating of the substrate are performed simultaneously, the processing time can be shortened. Since the substrate G is heated from the upper and lower sides by the upper planar heater 81 and the lower planar heater 71 , occurrence of warpage can be suppressed. The substrate G transported by the roller transport mechanism 5 is delivered to the transport mechanism on the cooling unit (COL) 29 side (in the case of the heat treatment unit (HT) 31 , the cooling unit (COL) 32 side) when passing through the output port 62 .

Next, the heat treatment unit (HT) 28 will be described in detail. In addition, since the heat treatment unit (HT) 31 also has completely the same structure as the heat treatment unit (HT) 28, the heat treatment unit (HT) 28 will be described here as a representative.

FIG. 2 is a plan view showing a lower heating portion of a heat treatment unit (HT) 28 (heat treatment device), and FIG. 3 is a side view. The heat treatment unit (HT) 28 includes a roller conveying mechanism 5 for conveying the substrate G toward one side in the Y direction, a frame body 6 provided to surround or accommodate the roller conveying mechanism 5, and is used for using the substrate G in the frame body 6. The roller conveyance mechanism 5 performs heating mechanisms 7 and 8 for heating the substrate G conveyed by the rollers.

The roller conveyance mechanism 5 arrange|positions the substantially columnar-shaped rotatable roller member 50 extended in the X direction in a plurality of rows at intervals in the Y direction. The roller members 50 are connected directly or indirectly to an unillustrated motor through a rotating shaft 51 or indirectly through gears, and are driven by the motor to rotate, whereby the substrate G is conveyed toward one side in the Y direction on the plurality of roller members 50 . .

In addition, each of the roller members 50 has a shape in contact with the substrate G in the entire width direction (X direction) of the substrate G. In order to make it difficult to transmit the heat of the substrate G heated by the heating mechanism 7, the roller outer peripheral surface 52 is made of resin or the like to conduct heat. It is made of a material with a low coefficient, and the rotating shaft 51 is a rotating shaft made of high-strength and highly corrosion-resistant ferritic stainless steel.

The frame body 6 is formed in a box shape, can accommodate the substrate G in a substantially horizontal state, and has a slit-shaped substrate input port 61 and a substrate output port 62 arranged in the substrate transfer direction (Y direction). The roller members 50 of the roller conveyance mechanism 5 are arranged in the frame body 6 so that the rotation shafts 51 are rotatably supported by bearings 60 provided on opposite side wall portions of the frame body 6 in the X direction.

Here, among the walls of the housing 6, the upper wall, the bottom wall, and the side walls facing in the Y direction have a double-wall structure including inner walls 63 and The outer wall 64 , the inner wall 63 , and the space 65 between the outer wall 64 function as an air insulation layer that insulates the inside and outside of the frame body 6 . A heat insulating material 66 for insulating the inside and outside of the housing 6 is provided on the inner surface of the outer wall 64 .

The heating mechanism 7 includes lower planar heaters 71 ( 71 a to 71 o ) as lower planar heating parts provided in the housing 6 along the transport path of the substrate G formed by the roller transport mechanism 5 , The lower planar heaters 71 are respectively provided on the back (lower surface) side of the substrate G conveyed by the roller conveyance mechanism 5 so as to be close to the substrate G conveyed by the roller conveyance mechanism 5 .

In addition, the heating mechanism 8 includes upper planar heaters 81 ( 81 a to 81 h ) as upper planar heating parts provided on the housing 6 along the conveyance path of the substrate G formed by the roller conveyance mechanism 5 . Inside, the upper planar heaters 81 are respectively provided on the surface (upper surface) side of the substrate G conveyed by the roller conveyance mechanism 5 so as to be close to the substrate G conveyed by the roller conveyance mechanism 5 .

In the case of a material with a lot of strain on the substrate G during heating, the upper surface body on the front (upper surface) side is placed in the same arrangement as the lower surface body heaters 71 (71a to 71o) on the back (lower surface) side. The shape heaters 81 ( 81 a to 81 h ) and the lower surface body shape heaters 71 ( 71 a to 71 o ) are arranged in vertical symmetry, thereby also reducing strain by making the upper and lower heat distribution uniform.

The lower planar heater 71 is formed so as to be divided in the X direction, and is respectively provided between the roller members 50 and arranged in a plurality in the Y direction (71a to 71o sequentially from the upstream side in the Y direction). The upper planar heater 81 is attached to and supported by, for example, side wall portions facing the housing 6 in the X direction. When controlling the heating of the substrate G in more detail, the upper planar heater 81 may be formed to be divided in the X direction.

In order to dissipate the heat in the housing 6 , exhaust ports 67 are respectively provided at the central portion in the transport direction and the upper wall portions at both ends, and an exhaust device 68 is connected to the exhaust ports 67 . Then, the inside of the housing 6 can be exhausted by the exhaust device 68 through the exhaust port 67 . For example, the exhaust port 67 may be formed in plural in the X direction, or may be formed in a slit shape extending in the X direction.

By arranging exhaust mechanisms at both ends of the frame body 6 in the Y direction and forming air curtains at the input port 61 and the output port 62 , external particles can be prevented from entering the frame body 6 from the input port 61 and the output port 62 . In addition, since the exhaust flow toward the Y direction is formed in the same direction as the conveyance direction of the substrate G, the particles generated inside the frame body 6 are discharged without generating turbulent air flow, and therefore, it is possible to prevent the particles from adhering to the substrate G. Substrate G.

In Fig. 3, the exhaust port 67 is disposed on the top of the frame body 6, but if it is desired to increase the discharge amount of heat and solvent, or to discharge a large amount of particles, it may also be located symmetrically with the upper exhaust port 67. The lower part has an exhaust port. In addition, the upper wall portion of the frame body 6 can be opened and closed at the central position in the conveyance direction (Y direction), and it is easy to clean the evaporated solvent adhering to the inner wall 63 and maintain the inside.

Next, the overall temperature control of the lower planar heater 71 will be described with reference to FIG. 6 . The control device 101 issues a command to set the temperature to the hot plate controller 104 . The hot plate controller 104 issues commands to the hot plate power supply 105 to set the temperature. In this case, the hot plate power supply is divided into six zones of 105a, 105b, 105c, 105d, 105e, and 105f. The lower planar heaters 71 are also arranged in sections 71a-71b, 71c-71d, 71e-71g, 71h-71j, 71k-71m, 71n-71o corresponding to the hot plate controller 104 on the Y-axis in the conveying direction. These 6 districts. Since the temperatures of the inlet, center, outlet, and width direction of the substrate G are different due to the air flow and the heat storage deviation of the inner wall, the heating power for each zone can be controlled for each zone.

In addition, the hot plate power supply 105 is divided into S, T, and U corresponding to the divisions of D, E, and F in the width direction of the lower planar heater 71 . For example, the zone D of the lower planar heaters 71a to 71b is controlled by S of the hot plate power supply 105a. Similarly, T of the hot plate power supply 105a controls the E zone of the lower surface heaters 71a to 71b, and U of the hot plate power supply 105a controls the F zone of the lower surface heaters 71a to 71b. S, T, and U of other hot plate power supplies 105b to 105f are also performed correspondingly to D, E, and F of the lower surface heaters 71c to 71d, 71e to 71g, 71h to 71j, 71k to 71m, and 71n to 71o. control.

Here, the temperature distribution of the heat treatment device 28 (31) will be described using FIG. An exhaust device 68 is connected to the exhaust port 67 . In addition, since the substrate input port 61 and the substrate output port 62 are opened, even if the same power is applied to the lower planar heater 71 and the upper planar heater 81, the temperatures at the center and both ends are low. In addition, the temperature of both end portions of the substrate G in the X direction increases due to the heat accumulation in the frame inner wall 63 shown in FIG. 2 . Even if the same electric power is applied in this way, the temperature is different, so it is necessary to be able to control the lower surface heater 71 and the upper surface heater 81 for each area in the conveyance direction (Y axis). Therefore, the lower planar heater 71 is divided into three areas of D, E, and F in the width direction of the substrate G (X-axis), and finely controlled.

FIG. 4 is a plan view showing a part of the lower planar heater 71 in cross section. The overall heat dissipation of the lower planar heater 71 is performed by a radiator 71p of aluminum, stainless steel, ceramics, or the like. The heat dissipation in the column E in FIG. 4 is performed by two parallel tubular heaters 71q embedded in the radiator 71p. The temperature is detected by the sensor 71 t , and the detected temperature is input to the hot plate controller 104 through the hot plate power supply 105 . The hot plate controller 104 issues commands to raise and lower the temperature according to the detected temperature. The hot plate power supply 105 supplies power to the hot plate on command. In the rows of D and F at both ends of the heat sink 71p, the tubular heater 71r and the tubular heater 71s are arranged so as to open blank areas (spaces) 71w and 71x with the tubular heater 71q, and the temperature sensor 71u The temperature of the tubular heater 71r is controlled, and the temperature of the tubular heater 71s is controlled by a temperature sensor 71v.

In FIG. 4, one tubular heater 71r, 71s is arrange|positioned with respect to two tubular heaters 71q. One tubular heater 71r, 71s corresponding to the rows D and F at both ends supplies lower heating power than the two tubular heaters 71q corresponding to the row E in the center. The reason for this is that the heat storage effect of the side wall portion of the frame body 6 can be used to maintain the temperature even if the calorific value of 71r and 71s is low. In addition, the tubular heater 71q and the tubular heaters 71r and 71s may be the same number of tubular heaters.

Next, the temperature distribution of the hot plate will be described using FIG. 7 . In (a) of FIG. 7 , lower planar heaters 71 for heating the lower portion (back surface) of the substrate G are divided into an E row at the center, and D and F rows at both ends. The upper portion (surface) of the substrate G is heated by the upper planar heater 81 .

(b) of FIG. 7 is a graph diagrammatically illustrating the electric power applied to the planar heater. Of the thermoelectric power applied to the E row in the center as the lower planar heater 71 and the thermoelectric power applied to the D and F rows at both ends, the thermoelectric power applied to the E row in the center is set to higher. In addition, blank areas (spaces) 71w and 71x for heating power exist between the tubular heaters 71r and 71s at both ends of the tubular heater 71q. This point can also be confirmed from FIG. 4 .

(c) of FIG. 7 is a diagram roughly illustrating an actual temperature distribution. The E row of the lower planar heater 71 can maintain the temperature corresponding to the heating of the tubular heater 71q, but at the same time, the temperature is maintained to approximately half of the spaces 71w and 71x by heat conduction. Similarly, the heat of the tubular heaters 71r and 71s is also maintained in approximately half of the space 71w and 71x by conduction. Since the electric powers D and F of the tubular heaters 71r and 71s are relatively low electric powers, the temperature is only the amount of Dh and Fh. However, the accumulated heat 63h in the wall portion of the frame body 6 conducts heat and is integrated with the heat of Dh and Fh to become the same temperature as the temperature of Eh.

In the spaces 71w and 71x, the integrated temperature can be adjusted by moving the tubular heaters 71r and 71s in the X direction. Through this adjustment, the central portion and both end portions of the lower planar heater 71 have an averaged temperature. As shown in FIG. 4, the central tubular heater 71q may be formed by a sheath heater, and the tubular heaters 71r and 71s at both ends may be formed by a cartridge heater.

In the structure of the jacket heater, the spiral heating wire (nickel-chromium alloy wire) is passed into the metal tube, and the heating wire and the metal tube are filled and sealed with high electrical insulation and thermal conductivity. Heat-resistant insulating material, therefore, can prevent the generation of particles. Electrical wiring is arranged at both ends of the heater. With this structure, it is embedded in the center of the lower planar heater, that is, the central tubular heater 71q. The thus formed jacket heater has excellent mechanical strength such as vibration and impact.

In the construction of a cassette heater, a heating wire (nickel-chrome wire) wound into a rod shape (such as ceramic) is inserted into a tube (such as stainless steel), and a material such as magnesium oxide, which is excellent in high thermal conductivity and high insulation, is used. (MgO) seals between the heating wire and the tube. Since the cassette heater can be wired in only one direction, it is possible to insert the heater into the hole in the metal region for heating, and also to adjust the temperature by adjusting the length of insertion. In addition, in the cassette heater, the uniformity of the generated temperature can be adjusted by inserting into both ends of the planar heater to adjust the distance from the jacket heater. The thus formed cassette heater is suitable as a heater that can withstand vibration without generating particles.

In this way, by forming the tubular heater 71q in the center by the jacket heater, and forming the tubular heaters 71r and 71s at both ends by the box heater, the substrate G of the present invention is a glass substrate for a flat panel display. In the case of a size of one meter, even if the vibration for conveying the substrate G is severe, the vibration can be withstood. In addition, ultra-miniaturization of the circuit pattern on the flat panel display and minimizing the generation of particles is an important issue, and it is also ideal for this point.

As shown in FIG. 3 , the upper planar heater 81 includes eight upper planar heaters 81 a to 81 h arranged on the upper surface (surface side) of the substrate G. As shown in FIG. Of these, the upper planar heaters 81d and 81e are divided from the middle of the conveyance direction width of the upper planar heaters 81a to 81c and 81f to 81h. The purpose is to open and close the upper wall portion of the frame body 6 at the center position in the transport direction (Y direction) to perform maintenance and internal cleaning.

FIG. 5 is a plan view showing a part of the upper planar heater 81 in cross section. The control method of the upper planar heater 81 is basically the same as that of the lower planar heater 71 , but it is not divided in the X direction. In addition, three tubular heaters 81q are embedded in the radiator 81p. The temperature of heat generation is detected by the sensor 81t. It is controlled by means of a hot plate controller 104 by means of a hot plate power supply 105 in FIG. 6 . In addition, one tubular heater is embedded in each of the upper planar heaters 81d and 81e.

As described above, according to the heat treatment apparatus of the embodiment, since the heat treatment can be carried out while the substrate G is conveyed, the processing time can be shortened, and the generation of the turbulent airflow can be suppressed by making the flow of the airflow the same as the conveyance direction of the substrate G. , and can prevent the generation of particles before it happens. In addition, based on the structure of the planar heaters 71, 81 and the hot plate controller 104, energy saving and heating uniformity of the substrate G can be realized by utilizing the heat storage on the side wall surface of the heat treatment device.

Next, a second embodiment will be described. In addition, the description of the same parts as those of the above-mentioned embodiment will be omitted, and only the different parts will be described. In 2nd Embodiment, as shown in FIG.

In the second embodiment, groove-shaped cutouts 92 are provided on the back surface 91 in the spaces 71w and 71x. The notch 92 is arranged, for example, in a linear shape when viewed from the direction of the arrow K. As shown in FIG. In addition, the cross-sectional shape of the notch 92 is a quadrangle. By providing the gaps 92 in this way, the heat conduction between the columns D, E, and F can be limited, so that the temperature distribution in the surface 90 can be further uniformed. In addition, the notch 92 can also be used for heat dissipation.

In addition, the cross-sectional shape of the notch 92 is not limited to a quadrangle, and may be an arc shape as shown in FIG. 9 . In addition, the cross-sectional shape of the notch 92 may be a triangular shape as shown in FIG. 10 .

When the cross-sectional shape of the notch 92 has a corner such as a quadrangle or a triangle at the tip of the notch 92, heat conduction tends to be uneven at the corner. By utilizing this point in reverse and making the cross-sectional shape of the notches 92 quadrilateral or triangular, the temperature distribution on the surface 90 can be made uniform.

In addition, when the cross-sectional shape of the notch 92 is arcuate and the tip of the notch 92 is formed gently, the heat conduction in this part is easy to be uniform. This point can also be utilized to make the cross-sectional shape of the notch 92 arc-shaped, so that the temperature distribution in the surface 90 can be made uniform.

Next, a third embodiment will be described. In addition, the description of the same parts as those of the above-mentioned embodiment will be omitted, and only the different parts will be described. In the third embodiment, a worker can take out the tubular heaters 71r and 71s from the radiator 71p or put them in the radiator 71p. That is, the insertion length of the tubular heaters 71r and 71s with respect to the radiator 71p can be changed. When the tubular heaters 71r, 71s are pulled out to the near side with respect to the radiator 71p, the spaces 71w, 71x expand. In addition, when the tubular heaters 71r and 71s are pushed into the radiator 71p, the spaces 71w and 71x are narrowed.

First, the temperatures of the tubular heaters 71q, 71r, and 71s are set to respective temperatures to be used, and the temperatures are raised. The temperature of the radiator 71p rises, and the temperature distribution is measured after the temperature of the radiator 71p stabilizes. Then, for example, if the temperature of the space 71w, 71x is lower than that of other parts, the operator pushes the tubular heater 71r, 71s into the radiator 71p to narrow the space 71w, 71x. Then, after the temperature of the radiator 71p stabilized, the temperature distribution of the radiator 71p was measured again. Such operations are repeated, and the positions of the tubular heaters 71r and 71s are adjusted so that the temperature of the radiator 71p becomes uniform. With this configuration, the temperature distribution of the radiator 71p can be made uniform.

In addition, the heat treatment apparatus of the present invention is suitable for particularly large substrates such as glass substrates for FPDs, but is not limited thereto, and can be widely used for heat treatment of other substrates such as semiconductor wafers.

Explanation of reference signs

G, substrate; 5, roller conveying mechanism; 6, frame body 7, heating mechanism; 8, heating mechanism; 50, roller member; 61, substrate input part; 62, substrate output part; 63, frame inner wall; 64, frame External wall; 65, air insulation layer; 66, heat insulating material; 71 (71a～71o), lower surface-shaped heater (lower surface-shaped heating part); 71p, radiator; 71q-71s, tubular heater; 71t-71v , temperature sensor; 71w, 71x, space; 81 (81a～81h), upper surface-shaped heater (upper surface-shaped heating part); 101, control device; 104, hot plate controller; 105, hot plate power supply.

Claims (9)

1. A heat treatment device, which is used for heat treatment of a substrate, characterized in that, The heat treatment device includes: a transport path for transporting the substrate in the horizontal direction; A frame body is provided to surround the conveyance path, and an exhaust mechanism for exhausting the interior is provided at the center part and both ends of the conveyance direction of the substrate; an upper surface body-shaped heating part, which is arranged in a plurality on the upper part of the above-mentioned conveying path; a lower surface body-shaped heating unit, which is arranged in a plurality of lower parts of the above-mentioned conveying path; Either one or both of the upper planar heating unit and the lower planar heating unit are divided in the conveying direction of the conveying path; At least the lower planar heating part of the upper planar heating part and the lower planar heating part is divided into a central part and both end parts in the width direction of the transport path; This heat treatment apparatus is formed so that the temperature of the said both ends can be controlled lower than the temperature of the divided said central part by a control device. 2. The heat treatment apparatus according to claim 1, wherein: At least one of the upper planar heating unit and the lower planar heating unit includes a planar radiator and a tubular heater embedded in the radiator. 3. The heat treatment apparatus according to claim 2, wherein: A first tubular heater is embedded in the central portion of the planar heating portion in the width direction, and a second tubular heater and a third tubular heater are respectively embedded in both sides of the planar heating portion in the width direction. and the third tubular heater are the same type of tubular heater. 4. The heat treatment apparatus according to claim 2, wherein: The end of the first tubular heater and the end of the second tubular heater, the end of the first tubular heater and the end of the third tubular heater are separated by a predetermined distance in the width direction of the transport path. separate. 5. The heat treatment apparatus according to claim 4, wherein: The first tubular heater is a jacket heater, and the second tubular heater and the third tubular heater are cassette heaters. 6. The heat treatment apparatus according to any one of claims 1 to 5, wherein: At least a part of the wall portion of the frame has a double-wall structure including an inner wall and an outer wall spaced apart from each other, and the space between the inner wall and the outer wall functions as an insulating material for insulating the inside and outside of the frame. The role of the insulating layer composed of air. 7. The heat treatment apparatus according to claim 4, wherein: The above-mentioned radiator in the shape of a plane body includes: a surface facing the substrate to be heat-treated; a back surface, which is the surface on the side opposite to the surface of the above-mentioned radiator in the form of a planar body; A notch, which is continuous from the back, is provided in the region between the above-mentioned separated ends. 8. A heat treatment device, which is used for heat treatment of a substrate, characterized in that, The heat treatment device includes: a transport path for transporting the substrate in the horizontal direction; A frame body is provided to surround the conveyance path, and an exhaust mechanism for exhausting the interior is provided at the center part and both ends of the conveyance direction of the substrate; an upper surface body-shaped heating part, which is arranged in a plurality on the upper part of the above-mentioned conveying path; a lower surface body-shaped heating unit, which is arranged in a plurality of lower parts of the above-mentioned conveying path; The upper planar heating unit and the lower planar heating unit are divided in the conveying direction of the conveying path; The upper planar heating part and the lower planar heating part are divided into a central part and both end parts in the width direction of the conveyance path; The upper planar heating part and the lower planar heating part each have heaters for heating inside the central part and the two end parts; The temperature of the heater at the central portion is set to be higher than the temperature of the heaters at the both ends. 9. The heat treatment apparatus according to claim 8, wherein: The temperature of the heater at the central part is set to be higher than the temperature of the heaters at the two ends by a predetermined value so that the heat accumulated in the frame is conducted to the two ends, and the temperatures at the two ends and The temperature of the said central part becomes the same temperature.

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