JP4014348B2 - Heat treatment device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat treatment apparatus for heating a substrate, which is used when a semiconductor device or the like is manufactured by applying and developing a substrate such as a semiconductor wafer.
[0002]
[Prior art]
In a photolithography process of a semiconductor device, a resist is applied to a semiconductor wafer (hereinafter simply referred to as a wafer), a resist film formed thereby is exposed according to a predetermined circuit pattern, and the exposure pattern is developed. Thus, a circuit pattern is formed on the resist film.
[0003]
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. .
[0004]
These heat treatments are usually performed by a hot plate unit in which a heating plate (hot plate) heated by a heater is disposed in the casing. During the heat treatment, the semiconductor wafer is placed close to or placed on the surface of the heating plate. At this time, the heating plate is placed over the entire surface of the placement surface so that the heat treatment can be performed at a uniform temperature over the entire surface of the wafer. The temperature is required to be uniform (in-plane uniformity).
[0005]
Therefore, in order to maintain the in-plane uniformity of the heating temperature, a plurality of ring-shaped heating elements are provided concentrically on the heating plate, and the temperature on the mounting surface is substantially uniform in the circumferential direction. The heating plate is covered with a cover during the heat treatment, and an air flow from the outer periphery of the heating plate to the center is formed therein, and the air is exhausted upward from the center of the cover.
[0006]
However, when forming an air flow from the outer periphery of the heating plate to the center, gas collects and stays in the exhaust port that exhausts upward from the center of the cover, so that dust, dust, or the like is mixed in the gas. Then, dust or dust from the staying gas may fall on the wafer and cause particle adhesion. Further, since the gas stays in the exhaust port that exhausts upward from the center of the cover in this way, the heat from the heating plate tends to act unevenly near the center of the wafer. Furthermore, since it is necessary to provide an exhaust mechanism at the center of the cover, the vertical dimension of the device itself must be increased.
[0007]
As a hot plate unit that can eliminate such an inconvenience, a unit that forms an airflow in one direction from one end to the other end on a heating plate has been proposed (for example, Japanese Patent Application Laid-Open No. 11-238661). . Since this hot plate unit only needs to provide an air inlet at one end of the cover on the heating plate and an air outlet at the other end, there is no need to provide an air outlet above the heating plate. There is no risk of dust falling on the upper surface of the wafer. Further, since there is no need to exhaust from the center of the cover, the heat from the heating plate does not act unevenly near the center of the wafer. Furthermore, since it is not necessary to provide an exhaust mechanism at the center of the cover, the vertical dimension of the device itself can be reduced.
[0008]
In this type of hot plate unit, a rectangular heating plate is arranged, and a plurality of linear heating elements are arranged in parallel to the direction perpendicular to the airflow in the heating plate. The resistance value of the heat generating element is not always uniform, and the amount of heat generation varies among the heat generating elements. Moreover, it is difficult for heat transfer to occur in the direction perpendicular to the airflow. Therefore, there is a problem that temperature variations tend to occur in the direction perpendicular to the airflow in the heating plate.
[0009]
In order to suppress such variations, it may be possible to provide a plurality of control channels in one heating element. However, as the entire heating plate, the number of control channels becomes too large, and the control of the heating element becomes extremely complicated. End up.
[0010]
[Problems to be solved by the invention]
This invention is made | formed in view of this situation, and it aims at providing the heat processing apparatus which can make the temperature uniformity of a heating plate favorable, without performing complicated control.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is, firstly, a heat treatment apparatus that heat-treats a substrate to a predetermined temperature, and a heating plate that heat-treats the substrate in the vicinity of or on the surface thereof, A plurality of heating elements that are arranged on the heating plate and generate heat when supplied with power, and a plurality of heat pipes arranged between the heating elements. The plurality of heating elements are linear and arranged substantially in parallel, and the plurality of heat pipes are linear and arranged between the adjacent heating elements and substantially parallel to the heating elements. ing A heat treatment apparatus characterized by the above is provided.
[0012]
Secondly, the present invention is a heat treatment apparatus for heat-treating a substrate to a predetermined temperature, and a heating plate for heat-treating the substrate close to or placed on the surface thereof, a heat plate disposed on the heat plate, and supplying power A plurality of heating elements that generate heat, a plurality of heat pipes disposed between the heating elements, and a unidirectional flow forming means for forming a one-way airflow from one end to the other end on the heating plate And the plurality of heating elements are linearly arranged, each being arranged substantially perpendicular to the direction of the airflow formed by the one-way flow forming means, and the plurality of heat pipes are linear. Provided is a heat treatment apparatus, wherein the heat treatment apparatus is arranged between the adjacent heat generating elements so as to be substantially parallel to the heat generating elements.
[0013]
According to the first aspect of the present invention, a plurality of heat pipes are arranged between a plurality of heating elements arranged on a heating plate, and the heat pipe uses the evaporation phenomenon and the condensation phenomenon of the working fluid filled therein. One heating element has the function of easily transporting a large amount of heat from one end to the other and the function of quickly transporting heat and making the temperature uniform when there is high or low temperature in it. Even in the case where the resistance value is non-uniform and the amount of heat generated is non-uniform in FIG. Even if complicated control such as providing the control channel is not performed, the temperature around the heating element can be maintained uniformly, and the temperature uniformity of the heating plate can be improved. In addition, due to such a temperature equalizing action of the heat pipe, there is a possibility that a heating plate having a large variation in the resistance value of the heating element can be used, and the yield of the apparatus can be increased. In addition, when a plurality of heating elements are arranged adjacent to each other, even if the temperature of one heating element is controlled to be kept uniform, it is affected by the heat from the adjacent heating elements, Although the temperature of the heating element rose and sometimes interfered with the adjacent heating element, according to the present invention, since the heat pipe is arranged between the adjacent heating lines, the adjacent heating element By eliminating the thermal influence of the wires, mutual interference can be eliminated, and the temperature control of the heating wires can be facilitated.
[0014]
Further, according to the second aspect of the present invention, in the one-way flow type heat treatment apparatus in which the one-way flow forming means forms a one-way air flow from one end to the other end on the heating plate, a plurality of linear shapes Are arranged substantially perpendicular to the direction of the airflow formed by the unidirectional flow forming means, and a plurality of linear heat pipes are arranged between the adjacent heating elements with respect to the heating elements. Since the heat pipes are arranged in parallel, the temperature of the heating plate can be controlled without complicated control in a unidirectional flow type heat treatment device that tends to cause temperature variations due to variations in the resistance value of the heating element due to the heat equalization of the heat pipe Uniformity can be improved.
[0015]
Thirdly, the present invention is a heat treatment apparatus for heat-treating a substrate to a predetermined temperature, and a heating plate for heat-treating the substrate close to or placed on the surface thereof, and a heat plate disposed on the heat plate and supplied with power. A plurality of heat generating elements that generate heat, and a plurality of heat pipes that respectively accommodate the heat generating elements. The plurality of heat pipes each include an inner tube that accommodates the heat generating element, and the inner tube. And a working fluid filled between the inner tube and the outer tube. A heat treatment apparatus is provided.
[0016]
Fourthly, the present invention is a heat treatment apparatus for heat-treating a substrate to a predetermined temperature, a heating plate for heat-treating the substrate close to or placed on the surface thereof, and a heat plate disposed on the heating plate for power supply. A plurality of heat generating elements that generate heat, a plurality of heat pipes that respectively accommodate the heat generating elements, and a one-way flow forming unit that forms a one-way air flow from one end to the other end on the heating plate; The plurality of heat pipes are linear, arranged substantially perpendicular to the direction of the airflow formed by the one-way flow forming means, and each of the inner pipes containing the heating elements, An outer tube that surrounds the inner tube, and a working fluid filled between the inner tube and the outer tube, and the plurality of heating elements are linear, each along the inner tube that forms a straight line It is characterized by being arranged To provide a heat treatment apparatus.
[0017]
According to the third and fourth aspects of the present invention, since a plurality of heat pipes having a structure in which a heating element is inserted in the inner pipe of a double pipe structure heat pipe are arranged on the heating plate, the temperature equalizing action of the heat pipe is achieved. Since it can exhibit more effectively, the temperature uniformity of a heating plate can be made still better. In addition, by providing the heating elements inside the heat pipe in this way, the arrangement density of the heating elements can be increased. Moreover, since the heating element and the heat pipe are integrated, assembly is easy.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
FIG. 1 is a schematic plan view showing a resist coating / development processing system for a wafer on which a hot plate unit according to an embodiment of the present invention is mounted, FIG. 2 is a front view thereof, and FIG. 3 is a rear view thereof.
[0019]
In this processing system, a wafer W is transferred 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 this purpose.
[0020]
The cassette station 10 carries in a semiconductor wafer (hereinafter simply referred to as a wafer) W as an object to be processed from another system in a state where a plurality of, for example, 25 wafers W are mounted on the wafer cassette CR. To carry out the wafer W from the wafer cassette CR to the processing station 11.
[0021]
In the cassette station 10, as shown in FIG. 1, a plurality of (four in the figure) positioning projections 20a are formed on the cassette mounting table 20 along the X direction in the figure, and at the positions of the projections 20a. The wafer cassette CR can be placed in a line with each wafer inlet / outlet facing the processing station 11 side. In the wafer cassette CR, the wafers W are arranged in the vertical direction (Z direction). The cassette station 10 has a wafer transfer mechanism 21 located between the wafer cassette mounting table 20 and the processing station 11. The wafer transfer mechanism 21 has a wafer transfer arm 21a that can move in the cassette arrangement direction (X direction) and the wafer arrangement direction (Z direction) of the wafer 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, and a third processing unit G on the processing station 11 side to be described later. ₃ An alignment unit (ALIM) and an extension unit (EXT) belonging to can be accessed.
[0022]
The processing station 11 is provided with a plurality of processing units for performing a series of steps when coating / phenomenon is performed on the semiconductor wafer W, and these are arranged in multiple stages at predetermined positions. W is processed one by one. As shown in FIG. 1, the processing station 11 has a 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. Yes. The plurality of processing units are divided into a plurality of processing units, and each processing unit includes a plurality of processing units arranged in multiple stages along the vertical direction.
[0023]
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 the wafer transfer device 46 can also be rotated integrally with the cylindrical support 49.
[0024]
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.
[0025]
Further, as shown in FIG. 1, in this embodiment, four processing units G ₁ , G ₂ , G ₃ , G ₄ Are actually arranged around the wafer transfer path 22a, and the processing unit G ₅ Can be arranged as needed.
[0026]
Of these, the first and second processing units G ₁ , G ₂ Are arranged in parallel on the front side of the system (front side in FIG. 1), and the third processing unit G ₃ Is arranged adjacent to the cassette station 10 and the fourth processing section G ₄ Is disposed adjacent to the interface unit 12. The fifth processing unit G ₅ Can be placed on the back.
[0027]
First processing unit G ₁ Then, a resist coating unit (COT) for coating a resist on the wafer W and a developing unit (DEV) for developing a resist pattern are stacked in two stages in order from the bottom. Second processing unit G ₂ Similarly, a resist coating unit (COT) and a developing unit (DEV) are stacked in two stages from the bottom as two spinner type processing units.
[0028]
Third processing unit G ₃ In 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, an adhesion unit (AD) that performs a so-called hydrophobic treatment for improving the fixability of the resist, an alignment unit (ALIM) that performs alignment, an extension unit (EXT) that carries in and out the wafer W, and a cooling process. A cooling unit (COL), four hot plate units (HP) that heat-treat 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.
[0029]
Fourth processing unit G ₄ Also, oven-type processing units are stacked in multiple stages. That is, 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.
[0030]
On the back side of the main wafer transfer mechanism 22 is a fifth processing unit G. ₅ Is provided, it can be moved laterally along the guide rail 25 as viewed from the main wafer transfer mechanism 22. Therefore, the fifth processing unit G ₅ Even 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.
[0031]
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 so that both cassettes CR and BR and the peripheral exposure device 23 can be accessed. ing. Further, the wafer transfer arm 24a is rotatable in the θ direction, and the fourth processing unit G of the processing station 11 is used. ₄ It 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.
[0032]
In such a resist coating and developing system, first, in the cassette station 10, the wafer transfer arm 21a of the wafer transfer mechanism 21 accesses the wafer cassette CR containing the unprocessed wafers W on the cassette mounting table 20. Then, one wafer W is taken out from the cassette CR, and the third processing unit G ₃ To the extension unit (EXT).
[0033]
The wafer W is transferred from the extension unit (EXT) to the processing station 11 by the wafer transfer device 46 of the main wafer transfer mechanism 22. And the third processing unit G ₃ After being aligned by the alignment unit (ALIM), it is transported to an adhesion processing unit (AD), where it is subjected to a hydrophobization process (HMDS process) for improving 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.
[0034]
After completion of the adhesion process, the wafer W cooled to a predetermined temperature by the cooling unit (COL) is subsequently transferred to the resist coating unit (COT) by the wafer transfer device 46, where a coating film is formed. After the coating process, ₃ , G ₄ Are pre-baked in one of the hot plate units (HP), and then cooled to a predetermined temperature in one of the cooling units (COL).
[0035]
The cooled wafer W is transferred to the third processing unit G. ₃ After being transferred to the alignment unit (ALIM) and aligned there, the fourth processing unit group G ₄ Are transferred to the interface unit 12 via the extension unit (EXT).
[0036]
In the interface unit 12, the peripheral exposure device 23 performs peripheral exposure for removing extra resist on, for example, a 1 mm portion on the periphery of the wafer, and then an exposure device (not shown) provided adjacent to the interface unit 12. Thus, the resist film on the wafer W is subjected to exposure processing according to a predetermined pattern.
[0037]
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. ₄ To 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 and subjected to post-exposure baking, and then cooled to a predetermined temperature by the cooling unit (COL).
[0038]
Thereafter, the wafer W is transferred to a developing unit (DEV) where the exposure pattern is developed. After the development process is completed, the wafer W is transferred to one of the hot plate units (HP), subjected to a post-bake process, and then cooled to a predetermined temperature by the cooling unit (COL). After such a series of processing ends, the third processing unit group G ₃ Is returned to the cassette station 10 via the extension unit (EXT) and accommodated in one of the wafer cassettes CR.
[0039]
Next, the hot plate unit according to the first embodiment of the present invention will be described with reference to FIGS. 4 is a cross-sectional view schematically showing the hot plate unit according to the first embodiment of the present invention, FIG. 5 is a block diagram showing its control system, and FIG. 6 is a schematic view of the heating plate portion of the hot plate unit of FIG. FIG. 7 is a schematic perspective view of the heat pipe provided in the hot plate unit of FIG.
[0040]
The hot plate unit (HP) has a casing 50, and a heating plate 51 having a rectangular shape is disposed on the lower side of the casing 50. The heating plate 51 includes a face plate 52 whose surface is a wafer facing surface and a bottom plate 53 provided below the face plate 52. Proximity pins 54 are provided on the surface of the face plate 52, and the wafer W is placed on the proximity pins 54 so as to be close to the surface of the face plate 52 of the heating plate 51. .
[0041]
A plurality of linear heating elements 60 are arranged substantially in parallel on the upper surface of the bottom plate 53, and the face plate 52 is arranged on the bottom plate 53, so that these heating elements 60 are attached to the heating plate 51. It will be buried. These heating elements 60 generate heat when energized, and heat the heating plate 51 to raise the temperature of the wafer W. In this case, it is preferable that the energization amount to each linear heating element 60 can be controlled independently.
[0042]
The heating plate 51 is supported by a support member 55, and the support member 55 is hollow. The heating plate 51 is formed with three through holes 56 (only two are shown in FIG. 4) at the center thereof, and the three lift pins 57 for raising and lowering the wafer W are formed in these through holes 56. It can be moved up and down. These elevating pins 57 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 55 via the support plate 58.
[0043]
A support ring 61 that surrounds and supports the heating plate 51 and the support member 55 is provided, and a cover 62 that is movable up and down is provided on the support ring 61. Then, the processing chamber S sealed from the outside by the seal ring 63 is formed with the cover 62 lowered to the upper surface of the support ring 61.
[0044]
One side of the heating plate 51 is provided with a gas supply nozzle 64 having a width of substantially one side of the heating plate 51 and for supplying a gas such as an inert gas or air into the processing chamber S. A gas supply pipe 65 for supplying a gas such as an inert gas or air is connected to the nozzle 64. The gas supply pipe 65 is provided with an electromagnetic valve 66 for adjusting the flow rate and flow velocity of the gas flowing therethrough.
[0045]
On the other hand, on the other side of the heating plate 51, there is provided an exhaust nozzle 67 having a width of substantially one side of the heating plate 51 and exhausting the gas in the processing chamber S. The exhaust nozzle 67 includes an exhaust pipe. 68 is connected. The exhaust pipe 68 is provided with an electromagnetic valve 69 for adjusting the exhaust amount.
[0046]
Then, the gas supplied from the gas supply nozzle 64 to the processing chamber S is exhausted from the exhaust nozzle 67, and the processing chamber S is moved from one end side to the other end side of the heating plate 51 as indicated by an arrow in FIG. Directional airflow is formed.
[0047]
A plurality of temperature sensors 70 are provided at appropriate positions in the face plate 52 of the heating plate 51, whereby the temperature of the heating plate 51 is measured. As shown in FIG. 5, the detection signal from the temperature sensor 70 is transmitted to a unit controller 71 for controlling the hot plate unit (HP). Based on the detection information, the detection signal is sent from the controller 71 to the temperature controller 72. A control signal is transmitted, and an output adjustment signal is transmitted from the temperature controller 72 to the heating element power supply 74 based on the control signal. Further, the unit controller 71 sends a control signal to the cylinder 59 to control the raising and lowering of the raising and lowering pins 57 during the heat treatment, and sends a control signal to the electromagnetic valves 66 and 69 to supply the gas from the gas supply nozzle 64. The supply amount and the exhaust amount from the exhaust nozzle 67 are controlled. The unit controller 71 outputs a control signal based on a command from a system controller (not shown) of the coating / developing system.
[0048]
The control of the heating element 60 by the unit controller 71 is located upstream of the unidirectional airflow formed on the heating plate 51 when the energization amount to each linear heating element 60 can be controlled independently. It is preferable to control so that the electric current supplied by the heating element and the heating element located on the downstream side is changed. That is, in the rectangular heating plate 51, the plurality of heating elements 60 are each linear and arranged substantially in parallel so that an airflow in one direction flows on the heating plate 51 in a direction substantially perpendicular to the heating element 60. Further, since the wafer W is slightly separated from the mounting surface by the proximity pins 54, the supplied gas flows to the back side of the wafer W, and more gas stays on the downstream side of the wafer W. However, if the supply current of the heating element 60 is the same, the temperature may increase slightly toward the downstream side of the wafer W. Therefore, when the heating element 60 is controlled by the unit controller 71, the current supplied by the heating element located on the upstream side and the heating element located on the downstream side of the airflow is changed. Specifically, the power source 74 is preferably controlled by the unit controller 71 so that a larger amount of current is supplied to the heating element 60 located on the upstream side than the heating element 60 located on the downstream side of the airflow. Thereby, the temperature of the heating plate 51 is maintained uniformly in the direction of the airflow (that is, the direction substantially perpendicular to the heating element 60).
[0049]
A plurality of linear heat pipes 80 are arranged between a plurality of linear heating elements 60 provided on the heating plate 51. Specifically, as shown in FIG. 4, the heat pipe 80 is fitted into a recess formed on the upper surface of the bottom plate 53, and as shown in the schematic perspective view of FIG. On the other hand, they are arranged perpendicular to the direction of the airflow in one direction. The plurality of heat pipes 80 and the heating elements 60 are preferably provided at substantially equal intervals.
[0050]
As shown in FIG. 7, the linear heat pipe 80 includes a container 81 as an outer shell member made of a cylindrical metal closed at both ends, for example, copper or a copper alloy, and a net-like shape provided on the inner peripheral wall thereof. It has a wick 82 as a member, and has a sealed structure filled with hydraulic fluid such as water. The wick 82 has a function of moving the working fluid by utilizing capillary action. This linear heat pipe 80 has a function of easily transporting a large amount of heat from one end to the other using the evaporation phenomenon and the condensation phenomenon of the working fluid filled therein, and has a high and low temperature therein. In some cases, it has a function of quickly transporting heat to make the temperature uniform. Specifically, for example, when one end of the heat pipe 80 is heated, the hydraulic fluid evaporates and becomes a vapor stream, moves at high speed to the low temperature portion, and then contacts the tube wall to be cooled and condensed. The condensate returns to the heating section due to the capillary action of the wick 82. Instead of using the wick 82, the condensate can be returned by gravity.
[0051]
When the heat treatment is performed by the hot plate unit (HP) configured as described above, first, the wafer W is loaded into the housing 50 of the hot plate unit (HP) by the wafer transfer device 46 and protruded. The lift pins 57 are transferred to the lifted pins 57 in the above state, the lift pins 57 are lowered, and the wafer W is placed on the proximity pins 54 provided on the surface of the face plate 52 of the heating plate 51.
[0052]
Next, the cover 62 is lowered to form the processing chamber S, and the electromagnetic valves 66 and 69 are controlled to form a unidirectional airflow in the processing chamber S from one end side to the other end side of the heating plate 51.
[0053]
In a state where such a unidirectional airflow is formed, the wafer W on the heating plate 51 is heated by supplying power to the heating element 60. As described above, since a one-way air flow is formed on the upper surface of the heating plate 51, an exhaust port is not provided in the central portion of the cover 62, and dust or dust does not fall on the upper surface of the wafer from the accumulated gas. . Further, since the gas does not stay above the vicinity of the center of the wafer W, the heat from the heating plate 51 does not act unevenly near the center of the wafer W. Furthermore, since it is not necessary to provide an exhaust structure such as an inert gas in the cover 62, the vertical dimension of the apparatus itself can be reduced.
[0054]
In this case, the resistance value of one linear heating element 60 is not necessarily uniform, variation in the amount of heat generation occurs in one heating element 60, and the heating element 60 is perpendicular to the air flow that hardly causes heat transfer. However, in this embodiment, since the heat pipe 80 is provided substantially in parallel between the heating elements 60, the temperature variation is likely to occur in the direction perpendicular to the airflow in the heating plate 51. The temperature equalizing action of the heat pipe 80 can maintain the temperature around the heating element 60 uniformly, and the temperature uniformity of the heating plate 51 can be improved. Therefore, it is sufficient to have one control channel for one heating element without performing complicated control such as providing a plurality of control channels in one heating element. It is sufficient that the temperature sensor 70 is also provided corresponding to each heating element 60.
[0055]
Further, even in the case of a heating plate that has a large variation in resistance value in the heating element 60 and has been a defective product in the past, due to the temperature equalizing action of the heat pipe 80, the amount of heat generated due to this variation in resistance value is non-uniform. Therefore, there is a possibility that it can be used as a product, and the yield of the product can be improved.
[0056]
Further, when a plurality of heating elements 60 are arranged adjacent to each other, even if the temperature of one heating element 60 is controlled to be kept uniform, it is affected by the heat from the adjacent heating elements 60 and is Although the temperature of the two heating elements 60 rises and may interfere with the adjacent heating elements 60, the heat pipe 80 is disposed between the adjacent heating elements 60 according to the present embodiment. Therefore, it is possible to eliminate the thermal influence of the adjacent heating elements 60 and eliminate mutual interference, and to facilitate the temperature control of the heating elements 60.
[0057]
Furthermore, when the circular wafer W is placed on such a rectangular heating plate 51, the end of the wafer W is affected by the heat from the placement surface on which the wafer W does not exist, and its temperature is Compared to the central portion of the wafer W, the temperature tends to rise and it is difficult to maintain the temperature uniformity between the end portion and the central portion of the wafer W, but the temperature of the heat pipe 80 disposed between the heating elements 60 is made uniform. Therefore, such inconvenience can be avoided.
[0058]
After the heat treatment of the wafer W is completed in this way, the cover 62 is moved upward, the wafer W is lifted by the lift pins 57, transferred to the wafer transfer device 46, and from the hot plate unit (HP). Unloaded and transported to the next process unit.
[0059]
In the above example, the heat pipe 80 is provided in the direction perpendicular to the air flow, and the temperature equalizing action is performed to equalize the temperature in the direction perpendicular to the air flow. As shown in FIG. A plurality of (only one is shown) vertical heat pipes 83 are provided on the back surface side of the heating plate 51 along the airflow direction (that is, substantially perpendicular to the heating element 60). The temperature may be equalized. That is, even when temperature non-uniformity occurs in the airflow direction in the heating plate 51, the non-uniformity can be eliminated by the temperature equalizing action of the vertical heat pipe 83, and the temperature uniformity of the heating plate 51 can be improved. This can be further improved. The structure of the vertical heat pipe 83 is the same as that of the heat pipe 80 shown in FIG.
[0060]
Next, a hot plate unit according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a cross-sectional view schematically showing the main part of a hot plate unit according to the second embodiment of the present invention, and FIG. 10 is a perspective view showing a double-pipe heat pipe used therefor.
[0061]
In the second embodiment, instead of the heat pipe 80 used in the first embodiment, a straight double pipe heat pipe 85 is used, and the plurality of double pipe heat pipes 85 are bottoms. They are arranged substantially parallel to the upper surface of the plate 53. As shown in FIG. 10, the double pipe heat pipe 85 includes an inner pipe 86, an outer pipe 87 surrounding the inner pipe 86, and a wick 88 provided between the inner pipe 86 and the outer pipe 87. And filled with hydraulic fluid such as water. A linear heating element 60 is inserted into the inner tube 86 along its longitudinal direction. Therefore, this double pipe type heat pipe 85 also has a function of easily transporting a large amount of heat from one end to the other end using the evaporation and condensation phenomenon of the hydraulic fluid, and a case where the temperature is high or low. It has the function of quickly transporting heat to make the temperature uniform.
[0062]
Therefore, even in the second embodiment, even if the heating element 60 has a variation in the amount of heat generated due to the variation in the resistance value, the temperature equalizing action of the double-tube heat pipe 85 causes the surroundings of the heating element 60 to be Can be maintained uniformly, and the temperature uniformity of the heating plate 51 can be improved. In this case, since the heating element 60 is provided in the heat pipe 85, the temperature equalizing action of the heat pipe 85 can be more effectively exhibited, and the variation in the amount of heat generated by the heating element 60 is further reduced. be able to. In addition, by providing the heating elements 60 inside the heat pipe 85 in this way, the arrangement density of the heating elements 60 can be increased. Further, since the heating element 60 and the heat pipe 85 are integrated, assembly is easy.
[0063]
Next, a hot plate unit according to a third embodiment of the present invention will be described with reference to FIGS. 11 is a cross-sectional view schematically showing a hot plate unit according to the third embodiment of the present invention, and FIG. 12 is a perspective view schematically showing a heating plate portion of the hot plate unit of FIG. 13 is a schematic view showing a part of the ring-shaped heat pipe provided in the hot plate unit of FIG.
[0064]
In the third embodiment, a circular heating plate 51 ′ is provided, and the heating plate 51 ′ includes a face plate 52 ′ and a bottom plate 53 ′. The heating plate 51 ′ is supported by a support member 55 ′, and the inside of the support member 55 ′ is hollow. A support ring 61 ′ is provided around the heating plate 51 ′ and the support member 55 ′, and a cover 62 ′ movable up and down is provided on the support ring 61 ′. Then, the processing chamber S ′ sealed from the outside is formed by the seal ring 63 ′ in a state where the cover 62 ′ is lowered to the upper surface of the support ring 61 ′. The cover 62 ′ has a conical shape that gradually increases from the outside toward the center, and has an exhaust port 93 connected to the exhaust pipe 94 at the center top.
[0065]
A gas supply port 91 for supplying a gas such as an inert gas or air to the processing chamber S ′ is provided along the heating plate 51 ′ at the upper end of the support ring 61 ′. Many gas supply ports 91 may be provided along the outer periphery of the heating plate 51 ′, or may be in a ring shape. A gas supply path 92 for supplying gas is connected to the gas supply port 91. Therefore, the gas supplied from the gas supply port 91 to the processing chamber S ′ is exhausted from the exhaust port 93 through the exhaust pipe 94, and an air flow from the periphery of the heating plate 51 ′ toward the center is formed in the processing chamber S ′. The
[0066]
A plurality of ring-shaped heating elements 90 are arranged substantially concentrically on the upper surface of the bottom plate 53 ′, and the face plate 52 ′ is arranged on the bottom plate 53 ′, so that these heating elements 90 are heated. It will be in the state embed | buried under plate 51 '. These heating elements 90 generate heat when energized from a power source (not shown), and heat the heating plate 51 to raise the temperature of the wafer W. In this case, it is preferable that the energization amount to each ring-shaped heating element 90 can be controlled independently.
[0067]
A plurality of temperature sensors 70 are provided at appropriate locations in the face plate 52 ′ of the heating plate 51 ′, whereby the temperature of the heating plate 51 ′ is measured. The detection signal from the temperature sensor 70 is transmitted to the unit controller 71 for controlling the hot plate unit (HP) shown in FIG. 5 as in the first embodiment, and the controller 71 outputs the temperature signal based on the detection information. A control signal is transmitted to the adjuster 72, and an output adjustment signal is transmitted from the temperature adjuster 72 to the heating element power source 74 based on the control signal, and the output of the heating element 90 is controlled.
[0068]
The control of the heating elements 90 by the unit controller 71 is performed on the outer peripheral side located on the upstream side of the airflow formed in the processing chamber S ′ when the energization amount to each ring-shaped heating element 90 can be controlled independently. It is preferable to control so as to change the current supplied between the heating element and the central heating element located on the downstream side. That is, since the wafer W is slightly separated from the mounting surface by the proximity pins 54, the supplied gas also flows to the back side of the wafer W, and the downstream side of the wafer W (that is, the central portion of the wafer W). If a large amount of gas stays and the supply current of the ring-shaped heating element 90 is the same, the temperature may slightly increase toward the downstream side of the wafer W (that is, toward the center of the wafer W). Therefore, when the heating element 90 is controlled by the unit controller 71, the heating element located on the upstream side (that is, the outer peripheral side of the wafer W) and the heat generation located on the downstream side (that is, the central portion of the wafer W). Changes the current supplied by the body. Specifically, the ring shape is located on the upstream side of the inert gas or the like (that is, the outer peripheral side of the wafer W) rather than the ring-shaped heating element 90 located on the downstream side of the airflow (that is, the center of the wafer W). It is preferable that the power source 74 is controlled by the unit controller 71 so as to supply more current to the heating element 90. Thereby, the temperature of the wafer W is maintained uniformly in the flow direction of the inert gas or the like (that is, from the periphery of the wafer W to the center).
[0069]
A plurality of ring-shaped heat pipes 95 are arranged between a plurality of ring-shaped heating elements 90 provided on the heating plate 51 ′. As shown in FIG. 13, the ring-shaped heat pipe has a ring-shaped cylindrical metal, for example, a container 96 made of copper or a copper alloy, and a wick 97 provided on the inner peripheral wall thereof. It has a sealed structure filled with hydraulic fluid such as water. The wick 97 has a function of moving the working fluid using a capillary phenomenon. This ring-shaped heat pipe 95 uses the evaporation and condensation phenomenon of the working fluid filled in the inside to quickly transport a large amount of heat, and quickly heats up when there is high or low temperature. It has the function of transporting and uniforming the temperature. Specifically, for example, when a part of the heat pipe 95 is heated, the hydraulic fluid evaporates and becomes a vapor stream, moves to the low temperature part at high speed, and then contacts the tube wall to be cooled and condensed. The condensate returns to the heating section due to the capillary action of the wick 97.
[0070]
When the heat treatment is performed by the hot plate unit (HP) configured as described above, first, the wafer W is loaded into the housing 50 of the hot plate unit (HP) by the wafer transfer device 46 and protruded. The lift pins 57 are transferred to the lifted pins 57 in the above state, the lift pins 57 are lowered, and the wafer W is placed on the proximity pins 54 ′ provided on the surface of the face plate 52 ′ of the heating plate 51 ′.
[0071]
Next, the cover 62 ′ is lowered to form the processing chamber S ′, gas is supplied from the gas supply port 91 to the processing chamber S ′, exhausted from the central exhaust port 93, and from the periphery of the heating plate 51 ′ to the center. A heading airflow is formed.
[0072]
In a state where such a unidirectional airflow is formed, the wafer W on the heating plate 51 ′ is heated by supplying power to the heating element 90.
[0073]
In this case, the resistance value of one ring-shaped heating element 90 is not necessarily uniform, and the amount of generated heat varies among the heating elements 90, and the heating plate 51 ′ is arranged along the arrangement direction of the heating elements 90. In this embodiment, the ring-shaped heat pipe 95 is provided between the ring-shaped heat generating elements 90, so that the temperature of the heat pipe 95 is equalized. The ambient temperature can be maintained uniformly, and the temperature uniformity of the heating plate 51 ′ can be improved. Therefore, it is sufficient to have one control channel for one heating element without performing complicated control such as providing a plurality of control channels in one heating element. It is sufficient if the temperature sensor 70 is also provided corresponding to each heating element 90. Further, since the ring-shaped heat pipe 95 is disposed between the adjacent ring-shaped heating elements 90, the thermal influence of the adjacent ring-shaped heating elements 90 is eliminated and mutual interference is eliminated. Thus, the temperature control of the heating element 90 can be facilitated.
[0074]
In addition, this invention is not limited to the said embodiment, A various deformation | transformation is possible. For example, in the above embodiment, the heating element and the heat pipe are linear or ring-shaped, but the present invention is not limited to this and may have other shapes. Further, the structure of the heat treatment apparatus is not limited to the hot plate unit exemplified in the above embodiment, and various forms are possible. Furthermore, although the heat treatment of the resist coating / development processing system has been described, the present invention can be applied to other heat treatments. Furthermore, in the above-described embodiment, the case where the wafer is placed on the proximity pin and heated indirectly is shown. However, the wafer may be placed directly on the heating plate and heated. Furthermore, although the case where a semiconductor wafer is used as the substrate has been described in the above embodiment, the present invention can also be applied to a case where heat treatment is performed on a substrate other than the semiconductor wafer, for example, an LCD substrate.
[0075]
【The invention's effect】
As described above, according to the present invention, a plurality of heat pipes are arranged between a plurality of heating elements arranged on the heating plate. However, since the heat pipe has a temperature equalizing action, Even in the case where the resistance value is non-uniform and the amount of heat generated is non-uniform, the heat equalizing action of the heat pipes arranged between adjacent heat generating elements can cause multiple heating elements Even if complicated control such as providing a control channel is not performed, the temperature around the heating element can be maintained uniformly, and the temperature uniformity of the heating plate can be improved. In addition, due to such a temperature equalizing action of the heat pipe, there is a possibility that a heating plate having a large variation in the resistance value of the heating element can be used, and the yield of the apparatus can be increased. In addition, when a plurality of heating elements are arranged adjacent to each other, even if the temperature of one heating element is controlled to be kept uniform, it is affected by the heat from the adjacent heating elements, Although the temperature of the heating element rose and sometimes interfered with the adjacent heating element, according to the present invention, since the heat pipe is arranged between the adjacent heating lines, the adjacent heating element By eliminating the thermal influence of the wires, mutual interference can be eliminated, and the temperature control of the heating wires can be facilitated.
[0076]
Further, according to the present invention, in the one-way flow type heat treatment apparatus that forms a one-way air flow from one end to the other end on the heating plate by the one-way flow forming means, a plurality of linear heating elements Are arranged substantially perpendicular to the direction of the air flow formed by the one-way flow forming means, and a plurality of linear heat pipes are arranged between the adjacent heating elements and substantially parallel to the heating elements. As a result, the temperature uniformity of the heating plate can be improved without complicated control in a one-way flow type heat treatment device that tends to cause temperature variations due to variations in the resistance value of the heating element due to the heat equalization of the heat pipe. Can be.
[0077]
Furthermore, according to the present invention, since a plurality of heat pipes having a structure in which a heating element is inserted in the inner pipe of a heat pipe having a double pipe structure are arranged on the heating plate, the temperature equalizing action of the heat pipe is more effectively exhibited. Therefore, the temperature uniformity of the heating plate can be further improved. In addition, by providing the heating elements inside the heat pipe in this way, the arrangement density of the heating elements can be increased. Moreover, since the heating element and the heat pipe are integrated, assembly is easy.
[Brief description of the drawings]
FIG. 1 is a plan view showing an overall configuration of a semiconductor wafer resist coating and developing treatment system including a hot plate unit as an embodiment of a heat treatment apparatus of the present invention.
FIG. 2 is a front view showing an overall configuration of a semiconductor wafer resist coating and developing treatment system including a hot plate unit according to an embodiment of the heat treatment apparatus of the present invention.
FIG. 3 is a rear view showing an overall configuration of a semiconductor wafer resist coating and developing treatment system including a hot plate unit according to an embodiment of the heat treatment apparatus of the present invention.
FIG. 4 is a cross-sectional view schematically showing a hot plate unit according to the first embodiment of the present invention.
FIG. 5 is a diagram showing a control system of the hot plate unit in FIG. 4;
6 is a perspective view schematically showing a heating plate portion of the hot plate unit of FIG. 4. FIG.
7 is a schematic view showing a heat pipe provided on the hot plate of FIG. 4 with a part cut away. FIG.
FIG. 8 is a cross-sectional view schematically showing a modification of the hot plate unit according to the first embodiment of the present invention.
FIG. 9 is a cross-sectional view schematically showing main parts of a hot plate unit according to a second embodiment of the present invention.
10 is a perspective view showing a double tube heat pipe used in the hot plate unit of FIG. 9;
FIG. 11 is a cross-sectional view schematically showing a hot plate unit according to a third embodiment of the present invention.
12 is a perspective view schematically showing a heating plate portion of the hot plate unit of FIG. 11. FIG.
13 is a schematic view showing a part of a ring-shaped heat pipe provided in the hot plate unit of FIG.
[Explanation of symbols]
51, 51 '; heating plate
54, 54 '; Proximity pins
57; Lift pin
60, 90; heating element
62, 62 '; cover
64; gas supply nozzle
65; gas supply pipe
66; solenoid valve
67; exhaust nozzle
68; exhaust pipe
69; Solenoid valve
70; temperature sensor
71; Unit controller (control means)
72; Temperature controller (control means)
74; heating element power supply
80; Linear heat pipe
85; Double pipe heat pipe
86; inner pipe
87; Outer tube
95; Ring-shaped heat pipe
S: Processing chamber
W: Semiconductor wafer

Claims (14)

A heat treatment apparatus for heat-treating a substrate to a predetermined temperature,
A heating plate that heats the substrate by placing the substrate close to or on its surface;
A plurality of heating elements that generate heat by being placed on the heating plate and fed with power,
A plurality of heat pipes disposed between the heating elements ,
The plurality of heating elements are linear and arranged substantially in parallel, and the plurality of heat pipes are linear and arranged between the adjacent heating elements and substantially parallel to the heating elements. The heat processing apparatus characterized by the above-mentioned. A heat treatment apparatus for heat-treating a substrate to a predetermined temperature,
A heating plate that heats the substrate by placing the substrate close to or on its surface;
A plurality of heating elements that generate heat by being placed on the heating plate and fed with power,
A plurality of heat pipes arranged between these heating elements;
A unidirectional flow forming means for forming a unidirectional airflow from one end to the other end on the heating plate;
The plurality of heating elements are linear and are arranged substantially perpendicular to the direction of the airflow formed by the one-way flow forming means, respectively, and the plurality of heat pipes are linear and each of the adjacent heating elements A heat treatment apparatus, wherein the heat treatment apparatus is arranged between the bodies substantially parallel to the heating element. 3. The control device according to claim 2, further comprising a control unit that changes a current supplied by a heating element located upstream and a downstream heating element of the airflow formed by the one-way flow forming unit. The heat treatment apparatus as described . 4. The heat treatment apparatus according to claim 1, wherein the plurality of heating elements and the plurality of heat pipes are arranged at substantially equal intervals . 5. 5. The heat treatment apparatus according to claim 1 , further comprising a vertical heat pipe disposed substantially perpendicular to the heating element on the heating plate. 6. A heat treatment apparatus for heat-treating a substrate to a predetermined temperature,
A heating plate that heats the substrate by placing the substrate close to or on its surface;
A plurality of heating elements that generate heat by being placed on the heating plate and supplied with power,
A plurality of heat pipes arranged between these heating elements
Comprising
The heat treatment apparatus according to claim 1, wherein the plurality of heating elements have a ring shape and are arranged concentrically, and the plurality of heat pipes have a ring shape and are arranged between the adjacent heating elements. The heat treatment apparatus according to claim 6 , wherein the plurality of heating elements and the plurality of heat pipes are arranged at substantially equal intervals. Heat treatment apparatus according to claim 6 or claim 7, characterized in that it comprises further the airflow forming means for forming an air flow toward the center from the periphery to the heating plate. It further comprises control means for changing the current supplied by the outer peripheral heating element located upstream of the air flow formed by the air flow forming means and the central heating element located downstream. The heat treatment apparatus according to claim 8 . A heat treatment apparatus for heat-treating a substrate to a predetermined temperature,
A heating plate that heats the substrate by placing the substrate close to or on its surface;
A plurality of heating elements that generate heat by being placed on the heating plate and fed with power,
A plurality of heat pipes for accommodating each of the heating elements,
Each of the plurality of heat pipes includes an inner pipe that houses the heating element, an outer pipe that surrounds the inner pipe, and a working fluid that is filled between the inner pipe and the outer pipe. A heat treatment apparatus. The plurality of heat pipes are linearly arranged and arranged substantially parallel to each other, and the plurality of heating elements are linearly arranged, and are respectively arranged along the straight inner pipes. The heat treatment apparatus according to claim 10 . Wherein the plurality of heat pipes without the ring, is arranged concentrically, claim 10 wherein the plurality of heating elements forms a ring shape, respectively, characterized in that it is arranged along the inner tube having a ring shaped The heat processing apparatus as described in. A heat treatment apparatus for heat-treating a substrate to a predetermined temperature,
A heating plate that heats the substrate by placing the substrate close to or on its surface;
A plurality of heating elements that generate heat by being placed on the heating plate and fed with power,
A plurality of heat pipes for accommodating each of the heating elements;
A unidirectional flow forming means for forming a unidirectional airflow from one end to the other end on the heating plate;
The plurality of heat pipes form a straight line and are arranged substantially perpendicular to the direction of the airflow formed by the one-way flow forming means, and each surrounds an inner tube that houses the heating element. And a plurality of working fluid filled between the inner tube and the outer tube, and the plurality of heating elements are linearly arranged along the linear inner tube. The heat processing apparatus characterized by the above-mentioned. Claim 1, wherein the temperature detecting means for detecting the temperature of the heating plate, further comprising a control means for controlling the current supplied to the heating element based on the detected temperature of the temperature detecting means The heat treatment apparatus according to claim 13 .

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