WO2020246268A1 - Substrate temperature control device and substrate temperature control method - Google Patents

Abstract

This substrate temperature control device, for controlling the temperature of a substrate is provided: with a mounting platform where the substrate is mounted; a temperature control unit which controls the temperature of the mounting platform in order to control the temperature of the substrate placed on the mounting platform; a suction force generating unit which generates a suction force for suctioning the substrate and adheres said substrate to the temperature-controlled mounting platform by suction and has a suction pipe which sucks in air around the substrate; and a suction force control unit which has a control gas tube which supplies to the suction force generating unit a suction force control gas for controlling the suction force.

Description

Board temperature control device and board temperature control method

The present disclosure relates to a substrate temperature control device and a substrate temperature control method.

Patent Document 1 discloses a technique for mounting a semiconductor wafer (hereinafter referred to as "wafer") on a mounting table of a heating device in a state in which the warp of the substrate is corrected. More specifically, in Patent Document 1, a suction member that protrudes from the surface of the mounting table is provided, and when the wafer delivered from the substrate transport mechanism by the elevating pin is placed on the mounting table, the wafer is mounted. The suction member is attracted to the lower surface. Then, the suction member and the elevating pin are lowered in synchronization with each other, and the wafer is placed on the mounting table. Furthermore, the suction pressure of the suction member is monitored by the pressure sensor to determine whether the suction member is attracted to the wafer, and after the suction member is attracted to the wafer, the suction pressure of the suction member is reduced. I have to. As a result, the load on the suction pump is reduced. Further, in Patent Document 1, a damper is provided in the suction pipe connected to the suction member, and the suction pressure on the suction member side is adjusted by the opening degree of the damper.

JP-A-2017-228696

The technology according to the present disclosure makes it possible to suck the substrate on the mounting table of the temperature control device with an appropriate suction force, and further improves the responsiveness at the time of switching the suction force and the reproducibility of the suction force.

One aspect of the present disclosure is a substrate temperature control device for adjusting the temperature of a substrate, which is a mounting table on which the substrate is mounted and a mounting table for adjusting the temperature of the substrate mounted on the above-described stand. The temperature control part that adjusts the temperature of the substrate and the suction force that sucks the substrate are generated, and the substrate is attracted to the above-mentioned stand whose temperature is adjusted, and the suction has a suction pipe that sucks the air around the substrate. A force generating unit and a suction force adjusting unit having an adjusting gas pipe for supplying the suction force adjusting gas for adjusting the suction force to the suction pipe are provided.

According to the present disclosure, the substrate can be attracted to the mounting table of the temperature adjusting device with an appropriate suction force, and the responsiveness at the time of switching the suction force and the reproducibility of the suction force can be improved.

It is a vertical cross-sectional view which shows the outline of the structure of the heat treatment apparatus as the substrate temperature control apparatus which concerns on 1st Embodiment. It is sectional drawing which shows the outline of the structure of the heat treatment apparatus as the substrate temperature control apparatus which concerns on 1st Embodiment. It is sectional drawing which shows the outline of the structure of a hot plate. It is a top view which shows the outline of the structure of a hot plate. It is explanatory drawing which shows the outline of the structure of the suction mechanism. FIG. 5 shows a piping system for explaining the outline of the configuration of the suction mechanism of FIG. 5, and is an explanatory diagram in a normal VAC mode. The piping system for explaining the outline of the structure of the suction mechanism of FIG. 5 is shown, and it is explanatory drawing in the high VAC mode. The piping system for explaining the outline of the structure of the suction mechanism of FIG. 5 is shown, and it is explanatory drawing in the super high VAC mode. FIG. 5 shows a piping system for explaining the outline of the configuration of the suction mechanism of FIG. 5, and is an explanatory diagram in the VAC-OFF mode. The piping system for explaining the outline of the structure of the suction mechanism of FIG. 5 is shown, and it is explanatory drawing in the idle mode. It is a vertical cross-sectional view which shows the outline of the structure of the heat treatment apparatus as the substrate temperature control apparatus which concerns on 2nd Embodiment. It is a vertical cross-sectional view which shows the outline of the structure of the heat treatment apparatus as the substrate temperature control apparatus which concerns on the modification of 2nd Embodiment. It is explanatory drawing which shows the outline of the structure of the suction mechanism provided in the heat treatment apparatus as the substrate temperature control apparatus which concerns on 3rd Embodiment. FIG. 13 shows a piping system for explaining the outline of the configuration of the suction mechanism of FIG. 13, and is an explanatory diagram in a normal VAC mode. FIG. 13 shows a piping system for explaining the outline of the configuration of the suction mechanism of FIG. 13, and is an explanatory diagram in the high VAC mode. FIG. 13 shows a piping system for explaining the outline of the configuration of the suction mechanism of FIG. 13, and is an explanatory diagram in the ultra-high VAC mode. FIG. 13 shows a piping system for explaining the outline of the configuration of the suction mechanism of FIG. 13, and is an explanatory diagram in the VAC-OFF mode. The piping system for explaining the outline of the structure of the suction mechanism of FIG. 13 is shown, and it is explanatory drawing in the idle mode. It is explanatory drawing which shows the outline of the structure of the heat treatment apparatus which concerns on a reference embodiment.

In the photolithography process in the manufacturing process of semiconductor devices and the like, a series of processes are performed in order to form a predetermined resist pattern on a wafer as a substrate. The series of treatments include a coating treatment of applying a resist liquid to form a resist film, an exposure treatment of exposing the resist film to a predetermined pattern, and a development treatment of applying a developing liquid to the exposed resist film for development. Includes heat treatment to heat the wafer. The heat treatment includes a post-exposure baking (PEB) treatment that promotes a chemical reaction in the resist film after exposure.

If the wafer is warped due to the influence of the process before the heat treatment, the distance between the hot plate for heating the wafer and the wafer varies in the wafer plane, and it becomes difficult to heat the wafer uniformly in the plane. .. Therefore, by sucking and adsorbing the wafer on a mounting table that functions as a hot plate in which a temperature control mechanism such as a heater is embedded, the wafer is placed on the mounting table with the warp of the wafer corrected. ing.

By the way, in the field of 3D NAND type semiconductor devices and the like, in recent years, the film formed on the wafer has become thicker, and the warpage of the wafer has increased (for example, up to several hundred μm). When the warp of the wafer is large as described above, a strong suction force is required to correct the warp.
However, according to the diligent studies of the present inventors, if the suction force is increased in order to eliminate a large warp, the wafer may be locally cooled by the air flow flowing between the wafer and the mounting table, and the wafer may be surfaced. It may not be possible to heat uniformly inside. This point becomes more remarkable as the suction force becomes stronger. Further, if the suction force is increased, the lower surface of the wafer may be scratched or the like.
Further, even if the amount of air sucked in the space formed between the wafer and the mounting table is the same, the pressure in the space changes depending on the temperature of the mounting table. Therefore, the suction amount required for correcting the warp of the wafer also changes depending on the temperature of the mounting table.

Note that Patent Document 1 discloses that a suction member that protrudes from the surface of the mounting table is provided, and after the suction member is attracted to the wafer, the suction pressure of the suction member is reduced. However, Patent Document 1 does not disclose the above-mentioned problems and the like when the suction force is increased. Further, in Patent Document 1, the change in suction pressure is adjusted by the opening degree of the damper. Since the damper is used so that its opening degree becomes a predetermined opening degree, it takes time from the start to the completion of the operation, and the responsiveness is poor. Therefore, when a damper is used as in Patent Document 1, it takes time to settle the suction pressure. Further, if the suction force is adjusted by the opening degree of the damper, the suction force changes with a slight variation in the opening degree, so that the reproducibility of the suction force is poor.

In view of the above points, the technique according to the present disclosure makes it possible to suck the substrate on the mounting table of the temperature control device with an appropriate suction force, and further, the responsiveness at the time of switching the suction force and the reproducibility of the suction force. To improve.

Hereinafter, the substrate temperature control device and the substrate temperature control method according to the present embodiment will be described with reference to the drawings. In the present specification and the drawings, elements having substantially the same functional configuration are designated by the same reference numerals to omit duplicate description.

(First Embodiment)
1 and 2 are a vertical sectional view and a horizontal sectional view showing an outline of the configuration of the heat treatment apparatus 1 as the substrate temperature control apparatus according to the first embodiment.
As shown in FIGS. 1 and 2, the heat treatment apparatus 1 includes a heating unit 11 for heat-treating the wafer W and a cooling unit 12 for cooling the wafer W in the housing 10. As shown in FIG. 2, on both side surfaces in the vicinity of the cooling portion 12 of the housing 10, carry-in / out outlets 13 for carrying in / out the wafer W are formed.

As shown in FIG. 1, the heating unit 11 is a hot plate accommodating unit that is located on the upper side and is movable up and down, and is located on the lower side and is integrated with the lid body 20 to form a processing chamber S. 21 is provided.

The lid 20 has a substantially tubular shape with an open lower surface, and covers the upper surface, which is the surface to be processed of the wafer W placed on the hot plate 30 described later. An exhaust portion 20a is provided at the center of the upper surface of the lid 20. The atmosphere in the processing chamber S is exhausted from the exhaust unit 20a.

A hot plate 30 as a mounting table is provided in the center of the hot plate accommodating portion 21. The hot plate 30 is for mounting the wafer W and heating the mounted wafer W. The hot plate 30 has a thick substantially disk shape, and a heater 31 as a temperature control portion for heating the upper surface of the hot plate 30, that is, the mounting surface of the wafer W is provided inside the hot plate 30. As the heater 31, for example, an electric heater is used.

The hot plate accommodating portion 21 is provided with an elevating pin 40 that penetrates the hot plate 30 in the thickness direction. The elevating pin 40 can be elevated and lowered by an elevating drive unit 41 such as a cylinder, and can project to the upper surface of the hot plate 30 to transfer the wafer W to and from the cooling plate 60 described later.

As shown in FIG. 1, the hot plate accommodating portion 21 includes, for example, an annular holding member 50 that accommodates the hot plate 30 and holds the outer peripheral portion of the hot plate 30, and a substantially tubular support that surrounds the outer peripheral portion of the holding member 50. It has a ring 51.

The cooling unit 12 adjacent to the heating unit 11 is provided with, for example, a cooling plate 60 on which the wafer W is placed and cooled. As shown in FIG. 2, the cooling plate 60 has a substantially rectangular flat plate shape, and the end surface on the heating portion 11 side is curved in an arc shape. A cooling member (not shown) such as a Peltier element is built in the cooling plate 60, and the cooling plate 60 can be adjusted to a predetermined set temperature.

The cooling plate 60 is supported by a support arm 61 as shown in FIG. 1, for example, and the support arm 61 is attached to a rail 62 extending in the X direction on the heating portion 11 side. The cooling plate 60 can be moved on the rail 62 by the drive mechanism 63 attached to the support arm 61. As a result, the cooling plate 60 can move above the hot plate 30 on the heating unit 11 side.

For example, the cooling plate 60 is formed with two slits 64 along the X direction in FIG. The slit 64 is formed from the end surface of the cooling plate 60 on the heating portion 11 side to the vicinity of the central portion of the cooling plate 60. The slit 64 prevents interference between the cooling plate 60 that has moved to the heating unit 11 side and the elevating pin 40 on the hot plate 30. As shown in FIG. 1, an elevating pin 65 is provided below the cooling plate 60 located in the cooling unit 12. The elevating pin 65 can be elevated by the elevating drive unit 66. The lifting pin 65 rises from below the cooling plate 60, passes through the slit 64, projects above the cooling plate 60, and enters, for example, the inside of the housing 10 from the carry-in outlet 13 (not shown). Wafer W can be delivered to and from.

The heat treatment apparatus 1 described above is provided with a control unit 70 as shown in FIG. The control unit 70 is, for example, a computer and has a program storage unit (not shown). A program for controlling processing in the heat treatment apparatus 1 is stored in the program storage unit. Further, the program storage unit also stores a program for controlling the operation of each of the above-mentioned parts and the suction mechanism described later to realize the heat treatment including the warp correction process described later in the heat treatment apparatus 1. The program may be recorded on a computer-readable storage medium and may be installed on the control unit 70 from the storage medium.

Next, the configuration of the hot plate 30 will be described in detail. 3 and 4 are a cross-sectional view and a plan view showing an outline of the configuration of the hot plate 30. FIG. 5 is an explanatory diagram showing an outline of the configuration of a suction mechanism described later.

As shown in FIGS. 3 and 4, the hot plate 30 is provided with the above-mentioned heater 31, and also has a through hole 32 through which the above-mentioned elevating pin 40 is inserted.
Further, a plurality of gap pins 33 as protrusions for supporting the wafer W are provided on the surface of the hot plate 30. As shown in FIG. 4, the gap pins 33 are provided at equal intervals on the circumference about the center of the hot plate 30 in a plan view. The height of the gap pin 33 is, for example, 0.05 mm or more and 0.1 mm or less.

Further, a plurality of suction holes 34 for sucking the lower surface of the wafer W are provided on the surface of the hot plate 30 at positions that do not overlap with the gap pins 33 in a plan view. The suction holes 34 are provided at equal intervals on the circumference about the center of the hot plate 30 in a plan view. In this example, in a plan view, the annular region provided with the suction hole 34 is located inside the annular region provided with the gap pin 33.

Since the gap pin 33 and the suction hole 34 are provided as described above, even if the wafer W is sucked, there is a gap between the wafer W and the hot plate 30, so that the wafer W is being sucked. , An air flow is generated along the lower surface of the wafer W. The in-plane uniform heating of the wafer W is hindered by this air flow.

Returning to the explanation of the hot plate 30.
As shown in FIG. 3, a flow path 35 extending downward is provided for each of the suction holes 34 in the hot plate 30. Each suction hole 34 is connected to the annular flow path 36 via the flow path 35. The annular flow path 36 is formed in an annular shape along the arrangement direction of the suction holes 34, and the suction mechanism 100 is connected to the annular flow path 36.

As shown in FIG. 5, the suction mechanism 100 has a suction force generating unit 101 and a suction force adjusting unit 102.

The suction force generating unit 101 generates a suction force for sucking the wafer W, corrects the warp of the wafer W, and attracts the wafer W to the temperature-controlled hot plate 30, and has a vacuum ejector 110. .. The vacuum ejector 110 has two inlets including a low pressure port 110a and a high pressure port 110b, and one outlet 110c.

A suction pipe 150 communicating with the annular flow path 36 of the hot plate 30, that is, communicating with the suction hole 34 is connected to the low pressure port 110a. Further, a main supply pipe 151 that leads to a supply source (not shown) of compressed air (hereinafter, may be referred to as "air") is connected to the high pressure port 110b. An exhaust pipe 152 leading to a duct D of the factory exhaust system (EXH) is connected to the outlet 110c.

In the suction force generating unit 101, when high-speed air is supplied to the high-pressure port 110b of the vacuum ejector 110 via the main supply pipe 151 and discharged from the outlet 110c of the vacuum ejector 110, the high-speed air is supplied. By being attracted, air is sucked from the low pressure port 110a of the vacuum ejector 110. As a result, the air around the wafer W is sucked into the suction pipe 150 through the suction hole 34, and a suction force for sucking the wafer W is generated.
The air sucked from the low pressure port 110a of the vacuum ejector 110 and the high-speed compressed air supplied to the high pressure port 110b are discharged from the outlet 110c to the exhaust pipe 152.

The suction pipe 150 is provided with a suction switching valve 111, and a pressure sensor 112 is provided on the upstream side of the suction switching valve 111.
Further, the main supply pipe 151 is provided with a speed controller 113 that adjusts the flow rate of high-speed air. A filter 114, a regulator 115, and a shutoff valve 116 are provided on the upstream side of the speed controller 113 in the main supply pipe 151 in this order from the upstream side. The filter 114 removes foreign matter in the air from the air source (not shown). The regulator 115 adjusts the pressure of the air on the secondary side to a predetermined pressure regardless of the pressure on the primary side. The shutoff valve 116 is for switching whether or not to shut off the supply of air via the regulator 115.

The suction force adjusting unit 102 weakens the suction force acting on the wafer W and adjusts the suction force, and supplies air as the suction force adjusting gas to the suction force generating unit 101 (specifically, for example, the suction pipe 150). It has a regulating gas pipe 153 to supply.

The adjusting gas pipe 153 includes a first pipe 153a that branches from the main supply pipe 151 and joins the suction pipe 150. One end of the first pipe 153a is connected to the portion between the shutoff valve 116 and the speed controller 113 in the main supply pipe 151, and the other end is between the vacuum ejector 110 and the suction switching valve 111 in the suction pipe 150. It is connected to the part.
The first pipe 153a is provided with a speed controller 117 and a switching valve 118 in this order from the upstream side. The speed controller 117 adjusts the flow rate of air supplied to the suction pipe 150 through the first pipe 153a. The switching valve 118 will be described later.

Further, the adjusting gas pipe 153 includes a second pipe 153b that bypasses the speed controller 117 in the first pipe 153a. One end of the second pipe 153b is connected to the upstream portion of the speed controller 113 in the first pipe 153a, and the other end is connected to the internal flow path of the switching valve 118. Further, the second pipe 153b is provided with a speed controller 119 and a switching valve 120 in this order from the upstream side. The speed controller 119 adjusts the flow rate of air supplied to the suction pipe 150 through the second pipe 153b. The switching valve 120 switches whether or not to supply the air whose flow rate is adjusted by the speed controller 119 to the switching valve 118. Further, the switching valve 118 described above switches the piping connected to the suction pipe 150 between the speed controller 117 side and the switching valve 120 side.

The speed controllers 117 and 119 and the switching valves 118 and 120 in the suction force adjusting unit 102 constitute a gas supply amount adjusting mechanism for adjusting the supply amount of air as the suction force adjusting gas to the suction pipe 150.

In the following description, the ON state of the suction switching valve 111 means a state in which the vacuum ejector 110 and the suction hole 34 communicate with each other via the suction pipe 150. On the other hand, the state in which the suction switching valve 111 is OFF means a state in which the suction pipe 150 is cut off at a portion between the vacuum ejector 110 and the suction hole 34. That is, when the suction switching valve 111 is ON, it means that air is sucked from the suction hole 34, and when the suction switching valve 111 is OFF, air is not sucked from the suction hole 34. Means the state. Further, the ON state of the switching valve 118 means a state in which the suction pipe 150 and the internal flow path of the switching valve 120 communicate with each other, and the OFF state of the switching valve 118 means that the suction pipe 150 and the speed controller 117 communicate with each other. Means the state of doing. The ON state of the switching valve 120 means that air is supplied to the switching valve 118 via the speed controller 119, and the OFF state of the switching valve 120 means that air is supplied to the switching valve 118. Means a state in which is not performed.

The suction mechanism 100 described above operates in a normal VAC mode, a high VAC mode, an ultra-high VAC mode, a VAC-OFF mode, and an idle mode.
The operation of the suction mechanism 100 in each mode will be described with reference to FIGS. 6 to 10. In these figures, the pipe through which the air sucked from the suction hole 34 and the compressed air from the source of the compressed air (not shown) is flowing is shown by a thick line to open and close some valves. Omits the explanation.

(Normal VAC mode)
In the normal VAC mode, as shown in FIG. 6, the shutoff valve 116 is opened, and of the suction switching valve 111, the switching valve 118, and the switching valve 120, only the suction switching valve 111 is turned on. In this case, the vacuum ejector 110 is supplied with air at a flow rate (for example, 40 L / min) controlled by the speed controller 113, so that the low pressure port 110a of the vacuum ejector 110 is supplied with a suction flow rate V (for example, 15 L / min). A suction flow of min) is generated. Then, the air of the flow rate D (for example, 13 L / min) controlled by the speed controller 117 is supplied (purged) to the suction pipe 150 via the switching valve 118, so that the flow rate Q of the suction air through the suction hole 34 Becomes smaller (for example, Q = VD = 15-13 = 2L / min).

(High VAC mode)
In the high VAC mode, as shown in FIG. 7, the shutoff valve 116 is opened, and the suction switching valve 111 and the switching valve 118 among the suction switching valve 111, the switching valve 118, and the switching valve 120 are in the ON state. Will be done. In this case, the suction flow rate V of the suction flow generated in the low pressure port 110a of the vacuum ejector 110 is the same as in the normal VAC mode, but since the switching valve 118 is in the ON state, the flow rate A controlled by the speed controller 119 (for example, 7L). / Min) of air is supplied to the suction pipe 150. Therefore, the flow rate Q of the suction air in the suction hole 34 is larger than that in the normal VAC mode (for example, Q = VA = 15-7 = 8 L / min). That is, in the high VAC mode, the suction force of the wafer W is stronger than the suction force in the normal VAC mode (hereinafter, referred to as "normal suction force").

(Ultra high VAC mode)
In the ultra-high VAC mode, as shown in FIG. 8, the shutoff valve 116 is opened, and the suction switching valve 111, the switching valve 118, and the switching valve 120 are all turned on. In this case, the suction flow rate V of the suction flow generated in the low pressure port 110a of the vacuum ejector 110 is the same as in the normal VAC mode, but since the switching valves 118 and 120 are in the ON state, the air for adjusting the suction force is sucked. Not supplied to pipe 150. Therefore, the flow rate Q of the suction air in the suction hole 34 is further larger than that in the high VAC mode (for example, Q = V = 15 L / min). That is, in the ultra-high VAC mode, the suction force of the wafer W is even stronger than in the high VAC mode, which is an ultra-strong suction force.

(VAC-OFF mode)
In the VAC-OFF mode, as shown in FIG. 9, the shutoff valve 116 is in the open state, but the suction switching valve 111 is in the OFF state. In this mode, air is not sucked through the suction hole 34.

(Idle mode)
In this mode, as shown in FIG. 10, the suction switching valve 111 is turned off as in the VAC-OFF mode, and the shutoff valve 116 is closed unlike the VAC-OFF mode. In this mode, since air is not supplied to the vacuum ejector 110, when the wafer W does not need to be adsorbed, the air consumption can be suppressed by operating in the mode.
A plurality of heat treatment devices 1 may be mounted on one semiconductor manufacturing device. At this time, if the supply source of compressed air is common among the heat treatment devices 1, specifically, the heat treatment device. It may be common among the suction mechanisms 100 of 1. In this case, if the regulator 115 is not provided in each suction mechanism 100, the flow rate of air in the other suction mechanism 100 fluctuates when one suction mechanism 100 is set to the idle mode or is returned from the idle mode. As a result, the suction force is insufficient and the adsorption of the wafer W and the correction of the warp of the wafer W are eliminated during the heat treatment, or the suction force becomes excessive and the heat treatment is performed by the airflow flowing between the wafer W and the hot plate 30. In-plane uniformity may be impaired. In order to prevent these, the suction mechanism 100 is provided with a regulator 115.

Subsequently, the heat treatment in the heat treatment apparatus 1 will be mainly described with respect to the warp correction treatment of the wafer W included in the heat treatment.

In the heat treatment apparatus 1, different heat treatments are performed according to the warped state of the wafer W. Specifically, for example, in the case of a concave wafer W having a large amount of warpage, in the case of a concave wafer W having a small amount of warpage, a different heat treatment is performed depending on the case of a convex wafer W. Which heat treatment is performed is set by the user for each lot, for example. The "warp amount" refers to the height of the outer peripheral portion of the wafer W with respect to the central portion.

(In the case of concave wafer W with a large amount of warpage)
When the wafer W has a concave shape, that is, a downwardly convex warp, and the amount of the warp is as large as several hundred μm or more, the wafer W is first sucked by the first suction force to correct the warp during the heat treatment. After being attracted to the hot plate 30, the wafer W is sucked by switching to a second suction force weaker than the first suction force.

Specifically, in the case of a concave wafer W having a large amount of warpage, for example, the suction mechanism 100 starts operating in the ultra-high VAC mode before the wafer W is placed (for example, several seconds before). .. Then, the elevating pin 40 is lowered, the wafer W is placed on the hot plate 30, and the heating of the wafer W is started. At this time, since the suction mechanism 100 is already operating in the ultra-high VAC mode, the ultra-strong suction force immediately acts on the wafer W as the first suction force, and the wafer W is attracted to the hot plate 30. The amount of warpage is corrected to, for example, 50 μm or less.
After a predetermined time has elapsed (for example, several seconds have passed) after the wafer W is placed on the hot plate 30, the suction mechanism 100 switches the operation from the ultra-high VAC mode to the high VAC mode. As a result, the suction force acting on the wafer W changes, and the strong suction force as the second suction force acts on the wafer W. Even if it is changed in this way, the strong suction force is set so that the correction of the warp of the wafer W is equivalent to the case where the wafer W is sucked by the super strong suction force.
After the heating of the wafer W is completed, the suction mechanism 100 switches the operation to the VAC-OFF mode to eliminate the adsorption and warpage correction of the wafer W. After that, the elevating pin 40 is raised, and the wafer W is carried out from the hot plate 30.

(In the case of concave wafer W with a small amount of warpage)
When the wafer W has a concave warp and the warp amount is as small as, for example, about 100 μm, the wafer W is sucked by the first suction force during the heat treatment to correct the warp, as in the case where the warp amount is large. After being attracted to the hot plate 30, suction is performed with a second suction force weaker than the first suction force. However, the strength of the first and second suction forces is different from the case where the amount of warpage is large.

Specifically, in the case of a concave wafer W having a large amount of warpage, for example, the suction mechanism 100 starts operating in the high VAC mode before the wafer W is placed (for example, several seconds before). Then, the elevating pin 40 is lowered, the wafer W is placed on the hot plate 30, and the heating of the wafer W is started. At this time, since the suction mechanism 100 is already operating in the high VAC mode, a strong suction force immediately acts on the wafer W as the first suction force, the wafer W is attracted to the hot plate 30, and the amount of warpage thereof. Is corrected to, for example, 50 μm or less.
After a predetermined time has elapsed (for example, several seconds have passed) after the wafer W is placed on the hot plate 30, the suction mechanism 100 switches the operation from the high VAC mode to the normal VAC mode. As a result, the suction force acting on the wafer W changes, and the normal suction force as the second suction force acts on the wafer W. Even if the wafer W is changed in this way, the normal suction force is set so that the correction of the warp of the wafer W is equivalent to the case where the wafer W is sucked by the strong suction force.
After the heating of the wafer W is completed, the suction mechanism 100 switches the operation to the VAC-OFF mode to eliminate the adsorption and warpage correction of the wafer W. After that, the elevating pin 40 is raised, and the wafer W is carried out from the hot plate 30.

(In the case of convex wafer W)
When the wafer W has a convex warp protruding upward, unlike the case where the wafer W has a concave warp, the wafer is sucked constantly with a weak suction force without changing the suction force during the heat treatment. To do.

In the case of the convex wafer W, specifically, for example, the suction mechanism 100 usually starts operating in the VAC mode before the wafer W is placed (for example, from a few seconds before). Then, the elevating pin 40 is lowered, the wafer W is placed on the hot plate 30, and the heating of the wafer W is started. At this time, since the suction mechanism 100 is already operating in the normal mode, the normal suction force immediately acts on the wafer W, the wafer W is attracted to the hot plate 30, and the amount of warpage is corrected to, for example, 50 μm or less. To. Then, the suction mechanism 100 operates in the normal VAC mode until the heating of the wafer W is completed, and after the heating is completed, the operation is switched to the VAC-OFF mode to eliminate the adsorption of the wafer W. After that, the elevating pin 40 is raised, and the wafer W is carried out from the hot plate 30.

In the above embodiment, the heat treatment apparatus 1 generates a suction force for sucking the wafer W and sucks the wafer W on the temperature-controlled hot plate, and sucks the air around the wafer W. A suction force generating unit 101 having 150 is provided. Further, the heat treatment apparatus 1 has a suction force adjusting unit having an adjusting gas pipe 153 that supplies air as a suction force adjusting gas for adjusting the suction force of the wafer W to the suction force generating unit 101 (specifically, the suction pipe 150). 102 is provided. Therefore, the wafer W can be adsorbed on the hot plate 30 in the heat treatment apparatus 1 with an appropriate suction force. As a result, it is possible to prevent the back surface of the wafer W from being scratched or cracked, and since the back surface of the wafer W is not scratched, the amount of particles adhering to the back surface can be reduced. It can be reduced, and further, the air consumption can be reduced.
Furthermore, in the present embodiment, the suction force of the wafer W is adjusted by supplying the suction force adjusting gas to the suction pipe 150 as described above. Therefore, by switching between supplying and stopping the supply of the suction force adjusting gas to the suction pipe 150 while supplying the force for producing the maximum suction force, that is, the valve for switching between the supply and the supply stop is simply opened and closed. This makes it possible to switch the magnitude of the suction force of the wafer W. Therefore, the responsiveness at the time of switching the suction force is higher than the case where the suction force is switched by the opening degree of the damper as in Patent Document 1. Further, when the suction force is switched by the opening degree of the damper as in Patent Document 1, the suction force varies due to a slight variation in the opening degree of the damper, but the suction force is switched by the suction force adjusting gas as in the present embodiment. Therefore, the risk of variation in suction power can be reduced. That is, the reproducibility of the suction force can be improved.

Further, in the present embodiment, the force required for the maximum suction force is always taken into the piping system. Therefore, by monitoring the pressure of the force (for example, with a pressure gauge provided on the outlet side of the regulator 115), it is possible to detect the case where the original force drops by just before the processing, and the next force is insufficient. It is possible to avoid the risk of proceeding with the processing of. That is, processing defects can be prevented.

When the suction force is switched according to the opening degree of the damper as in Patent Document 1, the suction force varies due to a slight variation in the opening degree of the damper. Therefore, by using a damper with high accuracy and high reproducibility, the suction force can be increased. There is a possibility that reproducibility and accuracy can be improved, but high-precision and high-reproducibility dampers are expensive. On the other hand, by switching between supplying and stopping the supply of the suction force adjusting gas to the suction pipe 150 as in the present embodiment, the reproducibility and accuracy of the suction force can be improved at low cost. In addition, the flow rate of the suction force adjusting gas can be controlled with high accuracy and high reproducibility by using an inexpensive speed controller, so that the suction force can be precisely adjusted with high accuracy, high reproducibility, and low reproducibility. It can be done at a cost.

Further, in the present embodiment, different heat treatments are performed depending on the warped state of the wafer W. Specifically, when a strong suction force is required to correct the warp, the wafer W is first sucked with a strong suction force (first suction force), attracted to the heat plate 30, and then sucked. The suction force is switched to the second suction force in which the suction force is weakened within the range in which the correction of the warp is maintained, and the heating of the wafer is continued. Therefore, since the local cooling of the wafer W due to the strong suction force can be suppressed, the wafer W can be heated uniformly in the plane. In addition, since the time for suction with a strong suction force is short, the amount of air consumed can be suppressed.

Further, in the present embodiment, a vacuum ejector 110 that generates a suction force by passing air is used as a suction force generation source that generates a suction force that acts on the wafer W. Then, the air to be passed through the vacuum ejector 110 and the air as the suction force adjusting gas are supplied from the same compressed air supply source, and the adjusting gas pipe 153 connects the compressed air supply source and the vacuum ejector 110. It is branched from the main supply pipe 151 in the heat treatment apparatus 1. Therefore, according to the present embodiment, it is not necessary to separately provide a gas system for the gas to be passed through the vacuum ejector 110 and the suction force adjusting gas, and one gas system is sufficient, so that the gas can be easily installed. .. Further, the suction pipe 150 can be cleaned by supplying air from the adjusting gas pipe 153 so as to flow back through the suction pipe 150.

Furthermore, in the present embodiment, the shutoff valve 116 is provided, and in the idle mode of the suction mechanism 100, the shutoff valve 116 is closed to shut off the air supply to the vacuum ejector 110 or the like. Therefore, the amount of air consumed can be reduced.

(Second Embodiment)
FIG. 11 is a vertical cross-sectional view showing an outline of the configuration of the heat treatment apparatus 2 as the substrate temperature control apparatus according to the second embodiment.
The heat treatment apparatus 2 of FIG. 11 has a distance sensor 80 as a warp state detection unit for detecting the warp state of the wafer W. The distance sensor 80 is provided above the cooling unit 12, and is in a warped state of the wafer W placed on the cooling plate 60, that is, a warped state of the wafer W before being heat-treated by the heating unit 11. Is for detecting.

The distance sensor 80 measures, for example, optically the distance from the distance sensor 80 to the portion of the wafer W directly below the distance sensor 80. A plurality of distance sensors 80 are provided, one distance sensor 80 measures the distance to the central portion of the wafer W, and the other distance sensor 80 measures the distance to the outer peripheral portion of the wafer W. Based on these measurement results, the state of warpage of the wafer W is detected, that is, the warp direction of the wafer W (whether the wafer is concave or convex) is detected and the amount of warpage is measured.

Then, the heat treatment apparatus 2 of the present embodiment operates as follows according to the detection result of the warp direction and the warp amount.
That is, in the first embodiment, different heat treatments are performed according to the warped state of the wafer W, and which heat treatment is performed is set by the user for each lot. On the other hand, in the present embodiment, the control unit 70 determines which heat treatment is to be performed according to the state of warpage of the wafer W detected from the measurement result by the distance sensor 80. In particular, when the wafer W is warped in a concave shape, the control unit 70 determines the above-mentioned first suction force and the second suction force based on the amount of warpage. Specifically, for example, in the control unit 70, when the amount of warpage of the concave wafer W exceeds a predetermined threshold value, the first suction force becomes the above-mentioned super strong suction force, and the second suction force becomes the second suction force. The first suction force and the second suction force are determined so that the force becomes the above-mentioned strong suction force. That is, the control unit 70 determines the operation order so as to switch from the ultra-high VAC mode to the high VAC mode during the heat treatment by using the ultra-high VAC mode and the high VAC mode as the operation modes of the suction mechanism 100. When the warp amount of the concave wafer W does not exceed a predetermined threshold value, the first suction force becomes the above-mentioned strong suction force, and the second suction force becomes the above-mentioned normal suction force. The first suction force and the second suction force are determined. That is, the high VAC mode and the normal VAC mode are used as the operation modes of the suction mechanism 100, and the control unit 70 determines the operation order so as to switch from the high VAC mode to the normal VAC mode during the heat treatment.

According to this embodiment, the heat treatment of the wafer W can be performed while automatically sucking the wafer unit with an appropriate suction force.
Further, since the first suction force becomes an appropriate suction force, the wafer W can be heated uniformly in the plane, and the possibility of scratches on the wafer W can be reduced. Further, since the second suction force becomes an appropriate suction force, the wafer W can be heated uniformly in the plane and the consumption of air can be reduced.

Further, in the present embodiment, the suction force acting on the wafer W may be corrected according to the amount of warpage of the wafer W.
For example, in the above example, when the amount of warpage of the concave wafer W exceeds a predetermined threshold value, the first suction force is the above-mentioned super strong suction force, and the second suction force is the above-mentioned strong suction force. Although it is regarded as a force, these super strong suction force and the strong suction force may be corrected according to the amount of warpage. This correction is performed so that, for example, the larger the amount of warpage, the greater the suction force.
Similarly, when the warp amount of the concave wafer W does not exceed a predetermined threshold value or when the convex wafer W is used, the suction force may be corrected according to the warp amount of the wafer W. ..

The flow rate of the first suction force and the suction force adjusting gas for forming the second suction force according to the amount of warpage of the wafer W is determined as follows, for example. That is, wafers W having various shapes are prepared, and the state of warpage of each wafer W is detected. Then, each wafer W is placed on the hot plate 30, the suction force adjusting gas is started to be supplied via the speed controller 117, and the supply amount is gradually increased. At this time, the wafer W is adsorbed and the pressure detected by the pressure sensor 112 may be greatly reduced. The suction force adjusting gas supply amount immediately before that is determined as the suction force adjustment gas supply amount for the first suction force corresponding to the warped state of the wafer W, and is stored in the control unit 70. Further, after adsorbing on the hot plate 30, the supply amount of the suction force adjusting gas is gradually reduced. At this time, the warp correction of the wafer W is eliminated, and the pressure detected by the pressure sensor 112 may be greatly increased. The suction force adjusting gas supply amount immediately before that is determined as the suction force adjustment gas supply amount for the second suction force corresponding to the warped state of the wafer W, and is stored in the control unit 70.

Further, as in the first embodiment, different heat treatments are performed according to the warped state of the wafer W, and which heat treatment is performed is set by the user for each lot. The suction force may be corrected according to the amount of warpage of the wafer W. In this case, for example, as in FIG. 11, it is necessary to provide the distance sensor 80 and measure the amount of warpage of the wafer W.

By performing the above-mentioned correction, the heat treatment of the wafer W can be performed while sucking with a more appropriate suction force according to the amount of warpage of the wafer W.

The position where the distance sensor 80 is provided as the warp state detection unit is not limited to the upper part of the cooling unit 12, and may be other than that.

(Modified example of the second embodiment)
FIG. 12 is a vertical cross-sectional view showing an outline of the configuration of the heat treatment apparatus 2 as the substrate temperature control apparatus according to the modified example of the second embodiment.
In the heat treatment apparatus 2 of FIG. 12, a temperature sensor 90 for measuring the temperature of the hot plate 30 is provided in the hot plate 30.
By the way, even if the amount of air sucked in the space formed between the wafer W and the hot plate 30 as the mounting table is the same, the pressure P in the space, that is, the suction force acting on the wafer W is the hot plate. It becomes stronger as the temperature of 30 rises. The pressure P is proportional to μ / ρ, where μ is the viscosity of the gas and ρ is the density of the gas. Then, when the temperature of the gas rises, the viscosity μ increases and the density ρ decreases, so that the pressure P increases. Specifically, when the temperature of the hot plate 30 is T and the room temperature is T ₀ , the above P is proportional to (T / T ₀ ) ^5/3 .
Therefore, in this example, the suction force acting on the wafer W is corrected according to the temperature T of the hot plate 30 measured by the temperature sensor 90.
For example, when the amount of warpage of the concave wafer W exceeds a predetermined threshold value, the first suction force is the above-mentioned super strong suction force, and the second suction force is the above-mentioned strong suction force. , These super strong suction force and strong suction force may be corrected according to the temperature of the hot plate 30. This correction corrects the suction force, that is, the flow rate of air as the suction force adjusting gas so that the suction force becomes smaller as the temperature is higher.
Similarly, when the amount of warpage of the concave wafer W does not exceed a predetermined threshold value or when the convex wafer W is used, the suction force may be corrected according to the temperature of the hot plate 30. ..

The flow rate of the suction force adjusting gas for making the first suction force and the second suction force according to the temperature of the hot plate is determined as follows, for example. For example, wafers W having various shapes are prepared, and the state of warpage of each wafer W is detected. Further, the temperature of the hot plate 30 is detected by using the temperature sensor 90. Then, each wafer W is placed on the hot plate 30, the suction force adjusting gas is started to be supplied via the speed controller 117, and the supply amount is gradually increased. At this time, the wafer W is adsorbed and the pressure detected by the pressure sensor 112 may be greatly reduced. The suction force adjusting gas supply amount immediately before that is determined as the suction force adjusting gas supply amount for the first suction force corresponding to the combination of the warp state of the wafer W and the temperature of the hot plate 30, and the control unit. It is stored in 70. Further, after adsorbing on the hot plate 30, the supply amount of the suction force adjusting gas is gradually reduced. At this time, the warp correction of the wafer W is eliminated and the pressure detected by the pressure sensor 112 is greatly increased. The suction force adjusting gas supply amount immediately before that is determined as the suction force adjusting gas supply amount for the first suction force corresponding to the combination of the warp state of the wafer W and the temperature of the hot plate 30, and the control unit. It is stored in 70.

Further, when the set temperature of the hot plate 30 is specified in the processing recipe, the suction force acting on the wafer W may be corrected according to the set temperature of the hot plate 30.

Further, as in the first embodiment, different heat treatments are performed according to the warped state of the wafer W, and which heat treatment is performed is set by the user for each lot. The suction force may be corrected according to the temperature of the hot plate 30.

By performing the above-mentioned correction, the heat treatment of the wafer W can be performed while sucking with a more appropriate suction force according to the temperature of the hot plate 30.

The suction force may be corrected according to the temperature of the wafer W before the heat treatment.

(Third Embodiment)
FIG. 13 is an explanatory diagram showing an outline of the configuration of the suction mechanism 200 included in the heat treatment device as the substrate temperature control device according to the third embodiment.
As shown in FIG. 13, the suction mechanism 200 according to the present embodiment has a suction force generating unit 201 and a suction force adjusting unit 202.

The suction force generating unit 201 generates a suction force for sucking the wafer W to correct the warp of the wafer W, and attracts the wafer W to the temperature-controlled hot plate 30. The suction force generating unit 201 is connected to a duct D of a factory exhaust system (EXH) provided with a blower fan B. A vacuum pump may be used instead of the blower fan B.

The suction force generating unit 201 has a suction pipe 250. One end of the suction pipe 250 communicates with the annular flow path 36 of the hot plate 30, that is, communicates with the suction hole 34, and the other end is connected to the duct D.
In the suction force generating unit 201, the air around the wafer W is sucked into the suction pipe 250 through the suction hole 34 by the operation of the blower fan B, and a suction force for sucking the wafer W is generated.
The air sucked into the suction pipe 250 is discharged to the duct D.

The suction pipe 250 is provided with a suction switching valve 210, and a pressure sensor 112 is provided on the upstream side of the suction switching valve 210. The suction switching valve 210 switches whether the suction target by the blower fan B is the air on the suction hole 34 side or the outside air.

The suction force adjusting unit 202 weakens the suction force acting on the wafer W and adjusts the suction force, and has an adjusting gas pipe 251 that supplies air as a suction force adjusting gas to the suction pipe 250.

The adjusting gas pipe 251 includes the first to third pipes 251a to 251c.

One end of the first pipe 251a is connected to a portion of the suction pipe 250 between the suction switching valve 210 and the duct D, and the other end is connected to a compressed air supply source (not shown).
The first pipe 251a is provided with a filter 114, a regulator 115, a shutoff valve 116, and a speed controller 211 in this order from the upstream side. The speed controller 211 adjusts the flow rate of air supplied to the suction pipe 250 via the speed controller 211.

The second pipe 251b bypasses the speed controller 211 in the first pipe 251a. One end of the second pipe 251b is connected to a portion between the shutoff valve 116 and the speed controller 211 in the first pipe 153a, and the other end is connected to a portion downstream of the speed controller 211 in the first pipe 153a. It is connected. The speed controller 212 and the switching valve 213 are provided in this second pipe 251b in order from the upstream side. The speed controller 212 adjusts the flow rate of air supplied to the suction pipe 250 via the speed controller 212. The switching valve 213 will be described later.

The third pipe 251c bypasses the speed controller 212 in the second pipe 251b. One end of the third pipe 251c is connected to the upstream portion of the speed controller 212 in the second pipe 251b, and the other end is connected to the internal flow path of the switching valve 213. Further, the third pipe 251c is provided with a speed controller 214 and a switching valve 215 in this order from the upstream side. The speed controller 214 adjusts the flow rate of air supplied to the suction pipe 250 via the speed controller 214. The switching valve 215 switches whether or not to supply the air whose flow rate is adjusted by the speed controller 214 to the switching valve 213. Further, the switching valve 213 described above switches the piping connected to the suction pipe 250 between the speed controller 212 side and the switching valve 215 side.

The speed controllers 211, 212, 214 and the switching valves 213 and 215 in the suction force adjusting unit 202 constitute a gas supply amount adjusting mechanism for adjusting the supply amount of air as the suction force adjusting gas to the suction pipe 250.

In the following description, the ON state of the suction switching valve 210 means a state in which the blower fan B sucks the air on the suction hole 34 side, while the OFF state of the suction switching valve 210 means the blower fan B. Means the state of sucking the outside air. Further, the ON state of the switching valve 213 means a state in which the suction pipe 250 and the internal flow path of the switching valve 215 communicate with each other, and the OFF state of the switching valve 213 means that the suction pipe 250 and the speed controller 212 communicate with each other. Means the state of doing. The ON state of the switching valve 215 means a state in which air is supplied to the switching valve 213 via the speed controller 214, and the OFF state of the switching valve 215 means that air is supplied to the switching valve 213. Means a state in which is not performed.

The suction mechanism 200 described above operates in a normal VAC mode, a high VAC mode, an ultra-high VAC mode, a VAC-OFF mode, and an idle mode.
The operation of the suction mechanism in each mode will be described with reference to FIGS. 14 to 18. In these figures, the pipe through which the air sucked from the suction hole 34 and the compressed air from the source of the compressed air (not shown) is flowing is shown by a thick line to open and close some valves. Omits the explanation.

(Normal VAC mode)
In the normal VAC mode, as shown in FIG. 14, the shutoff valve 116 is opened, and of the suction switching valve 210, the switching valve 213, and the switching valve 215, only the suction switching valve 210 is turned on. At this time, the output of the blower fan B, that is, the suction amount V by the blower fan B and the air flow rate C controlled by the speed controller 211 are adjusted so that the flow rate of the suction flow at the downstream end of the suction pipe 250 becomes a constant value. ing. That is, it is adjusted so that VC = constant (for example, 15 L / min). The reason for this adjustment is that when the blower fan B is shared by each suction mechanism 200, the suction flow rate by the blower fan B may differ between the suction mechanisms 200.
Further, air having a flow rate D (for example, 13 L / min) controlled by the speed controller 212 is supplied (purged) to the suction pipe 250 via the switching valve 213. Therefore, the flow rate Q of the suction air through the suction hole 34 becomes small (for example, Q = (VC) -D = 15-13 = 2 L / min).

(High VAC mode)
In the high VAC mode, as shown in FIG. 15, the shutoff valve 116 is opened, and the suction switching valve 210 and the switching valve 213 of the suction switching valve 210, the switching valve 213, and the switching valve 215 are in the ON state. Will be done. In this case, the flow rate of the suction flow at the downstream end of the suction pipe 250 is the same as in the normal VAC mode, but since the switching valve 213 is in the ON state, the flow rate A (for example, 7 L / min) controlled by the speed controller 212. Air is supplied to the suction pipe 250. Therefore, the flow rate Q of the suction air in the suction hole 34 is larger than that in the normal VAC mode (for example, Q = (VC) -A = 15-7 = 8 L / min). That is, in the high VAC mode, the suction force of the wafer W becomes a strong suction force stronger than the normal suction force, that is, the suction force in the normal VAC mode.

(Ultra high VAC mode)
In the ultra-high VAC mode, as shown in FIG. 16, the shutoff valve 116 is opened, and the suction switching valve 210, the switching valve 213, and the switching valve 215 are all turned on. In this case, the flow rate of the suction flow at the downstream end of the suction pipe 250 is usually the same as in the VAC mode, but since the switching valves 213 and 215 are in the ON state, the air is supplied from the switching valve 213 to the suction pipe 250. Not done. Therefore, the flow rate Q of the suction air in the suction hole 34 is further larger than that in the high VAC mode (for example, Q = VC = 15 L / min). That is, in the ultra-high VAC mode, the suction force of the wafer W is even stronger than in the high VAC mode, which is an ultra-strong suction force.

(VAC-OFF mode)
In the VAC-OFF mode, as shown in FIG. 17, the shutoff valve 116 is in the open state, but the suction switching valve 210 is in the OFF state. In this mode, air is not sucked through the suction hole 34. However, since the blower fan B continues to operate because it is shared with the suction mechanism 200 of the other heat treatment apparatus, the outside air is sucked into the suction pipe 250 via the suction switching valve 210.

(Idle mode)
In this mode, as shown in FIG. 18, the suction switching valve 210 is turned off as in the VAC-OFF mode, and unlike the VAC-OFF mode, the shutoff valve 116 is closed. In this mode, since air is not supplied to the suction pipe 250, when the wafer W does not need to be adsorbed, the air consumption can be suppressed by operating in the mode.
Even if the supply source of the compressed air is shared with the suction mechanism 200 of the other heat treatment apparatus, since the regulator 115 is provided, when one suction mechanism 200 is set to the idle mode or returned from the idle mode. In addition, the air flow rate does not fluctuate in the other suction mechanism 200. Therefore, it is possible to prevent the adsorption of the wafer W and the correction of the warp of the wafer W from being eliminated during the heat treatment.

Since the operation of the heat treatment apparatus as a whole in this embodiment is the same as that of the first embodiment except for the operation of the suction mechanism 200, the description thereof will be omitted.

This embodiment is preferably used when there are many sublimated products during heat treatment.
In the present embodiment as well, as in the first embodiment, since air as the suction force adjusting gas is supplied to the suction pipe 250, the wafer W can be attracted to the hot plate 30 with an appropriate suction force. it can.

Further, in the present embodiment, in the VAC-OFF mode and the idle mode in which air is not sucked through the suction hole 34, the operation of the blower fan B is not stopped, the suction switching valve 210 is switched, and the outside air is used by the blower fan B. I try to inhale. When the blower fan B is shared with another suction mechanism 200, when the suction flow rate by the blower fan B in the one suction mechanism 200 is set to zero when the VAC-OFF mode is set in the one suction mechanism 200, the other suction is performed. The suction flow rate by the blower fan B in the mechanism 200 fluctuates. According to this embodiment, this fluctuation can be prevented.

Also in this embodiment, the suction force may be changed according to the warped state of the wafer W and the temperature of the hot plate 30.

(Reference embodiment)
FIG. 19 is an explanatory diagram showing an outline of the configuration of the heat treatment apparatus 300 according to the reference embodiment.
The heat treatment apparatus 300 of FIG. 19 includes a hot plate 30 having a gap pin 33, a suction hole 34, an annular flow path 36, and a suction mechanism 310 that sucks the wafer W, corrects the warp, and sucks the wafer W on the hot plate 30. To be equipped. Further, the heat treatment apparatus 300 includes a distance sensor 80 as a warp state detection unit for detecting the warp state of the wafer W, as in the example of FIG. 11, and a hot plate as in the example of FIG. A temperature sensor 90 for measuring the temperature of 30 is provided.

The suction mechanism 310 included in the heat treatment apparatus 300 has a vacuum ejector 311. The vacuum ejector 311 has two inlets including a low pressure port 311a and a high pressure port 311b, and one outlet 311c.
A suction pipe 350 that communicates with the annular flow path 36 of the hot plate 30, that is, communicates with the suction hole 34, is connected to the low pressure port 311a. A pressure sensor 112 is connected to the suction pipe 350. Further, a supply pipe 351 leading to an air supply source (not shown) is connected to the high pressure port 311b. An electropneumatic regulator 312 is interposed in the supply pipe 351. An exhaust pipe 352 leading to the factory exhaust system is connected to the outlet 311c.

In the suction mechanism 310, high-speed air whose flow rate is controlled by the electropneumatic regulator 312 is supplied to the high-pressure port 311b of the vacuum ejector 311 via the supply pipe 351. When the high-speed air is discharged from the outlet 311c of the vacuum ejector 311, the air is attracted to the high-speed air and is sucked from the low-pressure port 311a of the vacuum ejector 311. As a result, the air around the wafer W is sucked into the suction pipe 350 through the suction hole 34, and a suction force for sucking the wafer W is generated.
The air sucked from the low pressure port 311a of the vacuum ejector 311 and the high-speed compressed air supplied to the high pressure port 311b are discharged from the outlet 311c to the exhaust pipe 352.

Further, the heat treatment apparatus 300 has a control unit 320. The control unit 320 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program that controls processing in the heat treatment apparatus 300. Further, the program storage unit also stores a program for controlling the operation of the suction mechanism 310 and the like to realize the heat treatment including the warp correction process in the heat treatment apparatus 1. The program may be recorded on a computer-readable storage medium and may be installed on the control unit 320 from the storage medium.

In the heat treatment apparatus 300, the control unit 320 controls the electropneumatic regulator 312 based on the warped state of the wafer W detected from the output of the distance sensor 80 and the temperature of the hot plate 30, and supplies air to the vacuum ejector 311. Control the amount. Thereby, the suction amount by the vacuum ejector 311, that is, the suction force of the wafer W is controlled. The measurement result of the pressure sensor 112 may also be used to control the amount of air supplied to the vacuum ejector 311.

Subsequently, the adsorption process of the wafer W in the heat treatment apparatus 300 will be described. In the following description, the wafer W to be adsorbed is preferably a wafer W in which the air supply amount of the vacuum ejector 311 is changed during the heat treatment, like the concave wafer W having a large warp amount. To do.

In the suction treatment, first, from a few seconds before the wafer W is placed on the hot plate 30, the state of warpage of the wafer W to be processed (the direction of the warp of the wafer W and the amount of warpage of the wafer W) and the temperature of the hot plate 30. The control unit 320 controls the electropneumatic regulator 312 so that the wafer W is sucked with the optimum suction force for correcting the warp according to the above. Specifically, the control unit 70 controls the distance sensor so that the supply amount of the warp correction air, which is optimal for the combination of the warp state of the wafer W to be processed and the temperature of the hot plate 30, is supplied to the vacuum ejector 311. The electropneumatic regulator 312 is controlled based on the measurement result of the 80 and the measurement result of the temperature sensor 90. The optimum amount of warp correction air supplied for each combination of the warp state of the wafer W and the temperature of the hot plate 30 is stored in advance in the control unit 320 as, for example, a data table.

Then, when the wafer W is placed on the hot plate 30, suction has already started as described above, so that the suction force suitable for warpage correction immediately acts on the wafer W, and the wafer W becomes hot. It is adsorbed on the plate 30 and the amount of warpage is corrected.

Next, a few seconds after the wafer W is placed on the hot plate 30, the wafer W has an optimum suction force for maintaining the warp correction according to the warp state of the wafer W to be processed and the temperature of the hot plate 30. The control unit 320 controls the electropneumatic regulator 312 so that the wafer is sucked. Specifically, the control unit 320 supplies the vacuum ejector 311 with the amount of air for maintaining the warp correction, which is optimal for the combination of the warp state of the wafer W to be processed and the temperature of the hot plate 30. The electropneumatic regulator 312 is controlled based on the measurement result of the distance sensor 80 and the measurement result of the temperature sensor 90. The optimum amount of air for maintaining warpage correction for each combination of the warp state of the wafer W and the temperature of the hot plate 30 is stored in advance in the control unit 320 as, for example, a data table.

Note that the amount of air supplied to the vacuum ejector 311 may be automatically controlled based on the measurement result of the pressure sensor 112 while the compulsion is maintained. The target pressure in this case is set based on the combination of the warped state of the wafer W to be processed and the temperature of the hot plate 30. The warped state of the wafer W and the target pressure for each combination of the temperatures of the hot plate 30 are stored in the control unit 320 as a data table.

After the heating of the wafer W is completed, the suction mechanism 310 eliminates the adsorption and warpage correction of the wafer W, and then the wafer W is carried out from the hot plate 30.

According to the embodiment of this reference, the in-plane uniformity of the wafer temperature can be further improved. Further, it is possible to prevent the back surface of the wafer W from being scratched or the wafer from being cracked. Further, the amount of particles adhering to the back surface of the wafer W can be reduced. Furthermore, air consumption can be reduced.

In the above description, the optimum supply amount of warp straightening air and the optimum supply amount of warp straightening maintenance air for each combination of the warp state of the wafer W and the temperature of the hot plate 30 are stored in advance as a data table. It was supposed to be. The optimum supply amount of warp correction air and the optimum supply amount of warp correction maintenance air described in these data tables may be calibrated as follows.

For example, wafers W of various shapes are prepared, and the state of warpage of each wafer W is detected. Further, the temperature of the hot plate 30 is detected by using the temperature sensor 90. Then, each wafer W is placed on the hot plate 30, the supply of air to the vacuum ejector 311 is started, and the supply amount is gradually increased. At this time, since the wafer W is attracted and the pressure detected by the pressure sensor 112 is greatly reduced, the amount of air supplied immediately before that is determined by the combination of the warped state of the wafer W and the temperature of the hot plate 30. Correct the data table as the optimum amount of air for warp correction. Further, after adsorbing on the hot plate 30, the amount of air supplied to the vacuum ejector 311 is gradually reduced. At this time, since the warp correction of the wafer W is eliminated and the pressure detected by the pressure sensor 112 is greatly increased, the amount of air supplied immediately before that is determined by the state of the warp of the wafer W and the hot plate 30. Correct the data table, etc. as the optimum supply amount of correction maintenance air for the combination of temperatures.

Note that the above-mentioned data table configuration may be performed for each heat treatment apparatus 300. As a result, the wafer W can be sucked with the optimum suction force for each heat treatment apparatus 300.

In the above explanation, the temperature control device is assumed to be a heat treatment device that performs heat treatment. However, the temperature control device according to the present disclosure may be a cooling device that performs a cooling process.

The embodiments disclosed this time should be considered to be exemplary in all respects and not restrictive. The above-described embodiment may be omitted, replaced, or changed in various forms without departing from the scope of the appended claims and the gist thereof.

The following configurations also belong to the technical scope of the present disclosure.

(1) A substrate temperature control device that adjusts the temperature of the substrate.
The mounting table on which the board is mounted and
A temperature control unit that adjusts the temperature of the pedestal to adjust the temperature of the substrate mounted on the pedestal described above.
A suction force generating part having a suction pipe for sucking the air around the substrate, which generates a suction force for sucking the substrate and attracts the substrate to the above-mentioned stand whose temperature is adjusted,
A substrate temperature control device including a suction force adjusting unit having an adjusting gas pipe for supplying the suction force adjusting gas for adjusting the suction force to the suction force generating unit.
According to the above (1), since the suction force can be adjusted, the warp of the substrate can be corrected with an appropriate suction force and the substrate can be adsorbed. Therefore, the temperature of the substrate can be uniformly treated in the plane, and it is possible to prevent the substrate from being scratched or the like.

(2) The suction force includes a first suction force and a second suction force weaker than the first suction force.
The suction force adjusting unit has a gas supply amount adjusting mechanism for adjusting the supply amount of the suction force adjusting gas.
The substrate temperature control device adjusts the gas supply amount so that the suction force acting on the substrate is switched from the first suction force to the second suction force after the substrate is attracted to the above-mentioned table. The substrate temperature control device according to (1) above, which includes a control unit that controls the mechanism.
According to the above (2), the temperature of the substrate can be treated more uniformly in the plane. Further, when a gas is used to generate the suction force, the consumption of the gas can be suppressed.

(3) The above-described (2), wherein the control unit determines the first suction force and the second suction force according to the state of warpage of the substrate before being attracted to the above-mentioned table. Board temperature control device.
According to the above (3), the warp of the substrate can be corrected with a more appropriate suction force and the substrate can be adsorbed. Therefore, the temperature of the substrate can be treated more uniformly in the plane, and the possibility of scratches on the substrate can be further reduced.

(4) The control unit determines the first suction force and the second suction force based on at least one of the warpage amount of the substrate before being adsorbed on the description table and the temperature of the table. The substrate temperature control device according to (2) or (3) above, which corrects at least one of them.
According to the above (4), the warp of the substrate can be corrected with a more appropriate suction force and the substrate can be adsorbed.

(5) The suction force generating portion has a vacuum ejector that generates the suction force by passing gas through the suction force generating portion.
The gas flowing through the vacuum ejector and the suction force adjusting gas are supplied from the same gas supply source.
The adjustment gas pipe according to any one of (1) to (4) above, wherein the adjusting gas pipe is branched in the substrate temperature control device from the main supply pipe connecting the gas supply source and the vacuum ejector. Board temperature control device.
According to the above (5), it is not necessary to separately provide a gas system for the gas to be passed through the vacuum ejector and the suction force adjusting gas, and one gas system is sufficient, so that the gas can be easily installed. Further, the suction pipe can be cleaned by supplying air from the adjusting gas pipe so that the suction pipe flows backward.

(6) The substrate temperature control device according to (5) above, which has a shutoff valve on the upstream side of the branch point to the regulated gas pipe and a pressure regulator on the upstream side of the shutoff valve in the main supply pipe.
According to (6) above, the consumption of the suction force adjusting gas can be suppressed, and when the supply of the suction force adjusting gas is stopped, the supply of the suction force adjusting gas of another device is affected. Can be prevented.

(7) The force for sucking the air around the substrate in the suction force generating portion is generated by a blower fan or a vacuum pump.
The substrate temperature control device according to any one of (1) to (4) above, wherein the suction pipe has a switching valve for switching between suction around the substrate and suction of outside air.
According to (7) above, even if the blower fan or the vacuum pump is shared by a plurality of substrate temperature control devices, the stop of suction around the substrate by the blower fan or the vacuum pump in one substrate temperature control device can be achieved. It does not affect the suction in other substrate temperature control devices. Therefore, it is not necessary to provide a blower fan or the like for each substrate temperature control device, so that the installation cost can be reduced.

(8) A substrate temperature control method for adjusting the temperature of the substrate.
A temperature control process that adjusts the temperature of the mounting table on which the board is placed,
The mounting process of mounting the substrate on the temperature-controlled stand described above, and
It has a suction step of adsorbing the substrate to the above-mentioned pedestal by the suction force by sucking air from the suction force generating part having the suction pipe from the periphery of the substrate on the above-mentioned pedestal.
The suction step is a substrate temperature control method including a suction force adjusting step of supplying a suction force adjusting gas to the suction force generating portion to adjust the suction force.

(9) The suction force adjusting step is performed on the suction force generating portion so that the first suction force is switched to a second suction force weaker than the first suction force after the substrate is sucked onto the above-mentioned stand. The substrate temperature control method according to (8) above, wherein the supply amount of the suction force adjusting gas is adjusted.

(10) The substrate temperature according to (9) above, which comprises a step of determining the first suction force and the second suction force according to the state of warpage of the substrate before being adsorbed on the above-mentioned stand. How to adjust.

(11) The first suction force and the second suction force are corrected based on at least one of the warpage amount of the substrate before being adsorbed on the above-mentioned stand and the temperature of the above-mentioned stand. The substrate temperature control method according to any one of 9) or (10).

1, 2 Heat treatment device 30 Hot plate 31 Heater 101, 201 Suction force generating section 102, 202 Suction force adjusting section 150, 250 Suction piping 153, 251 Adjusting gas piping W wafer

Claims (11)

A board temperature control device that regulates the temperature of the board.
The mounting table on which the board is mounted and
A temperature control unit that adjusts the temperature of the pedestal to adjust the temperature of the substrate mounted on the pedestal described above.
A suction force generating part having a suction pipe for sucking the air around the substrate, which generates a suction force for sucking the substrate and attracts the substrate to the above-mentioned stand whose temperature is adjusted,
A substrate temperature control device including a suction force adjusting unit having an adjusting gas pipe for supplying the suction force adjusting gas for adjusting the suction force to the suction force generating unit. The suction force includes a first suction force and a second suction force weaker than the first suction force.
The suction force adjusting unit has a gas supply amount adjusting mechanism for adjusting the supply amount of the suction force adjusting gas.
The substrate temperature control device adjusts the gas supply amount so that the suction force acting on the substrate is switched from the first suction force to the second suction force after the substrate is attracted to the above-mentioned table. The substrate temperature control device according to claim 1, further comprising a control unit for controlling the mechanism. The substrate temperature control device according to claim 2, wherein the control unit determines the first suction force and the second suction force according to the state of warpage of the substrate before being attracted to the above-mentioned stand. .. The control unit has at least one of the first suction force and the second suction force based on at least one of the amount of warpage of the substrate before being adsorbed on the description table and the temperature of the table. The substrate temperature control device according to claim 2 or 3, wherein one of them is corrected. The suction force generating portion has a vacuum ejector that generates the suction force when gas is passed through the suction force generating portion.
The gas flowing through the vacuum ejector and the suction force adjusting gas are supplied from the same gas supply source.
The substrate temperature according to any one of claims 1 to 4, wherein the adjusting gas pipe is branched in the substrate temperature control device from a main supply pipe connecting the gas supply source and the vacuum ejector. Tuning device. The substrate temperature control device according to claim 5, further comprising a shutoff valve on the upstream side of the branch point to the regulating gas pipe and a pressure regulator on the upstream side of the shutoff valve in the main supply pipe. The force for sucking the air around the substrate in the suction force generating portion is generated by a blower fan or a vacuum pump.
The substrate temperature control device according to any one of claims 1 to 4, wherein the suction pipe has a switching valve for switching between suction around the substrate and suction of outside air. It is a substrate temperature control method that adjusts the temperature of the substrate.
A temperature control process that adjusts the temperature of the mounting table on which the board is placed,
The mounting process of mounting the substrate on the temperature-controlled stand described above, and
It has a suction step of adsorbing the substrate to the above-mentioned pedestal by the suction force by sucking air from the suction force generating part having the suction pipe from the periphery of the substrate on the above-mentioned pedestal.
The suction step is a substrate temperature control method including a suction force adjusting step of supplying a suction force adjusting gas to the suction force generating portion to adjust the suction force. In the suction force adjusting step, the suction force to the suction force generating portion is switched from the first suction force to the second suction force weaker than the first suction force after the substrate is sucked onto the above-mentioned stand. The substrate temperature control method according to claim 8, wherein the supply amount of the adjusting gas is adjusted. The substrate temperature control method according to claim 9, further comprising a step of determining the first suction force and the second suction force according to the state of warpage of the substrate before being adsorbed on the pedestal. 9 or 10 of claim 9 or 10 for correcting the first suction force and the second suction force based on at least one of the warpage amount of the substrate before being adsorbed on the above-mentioned stand and the temperature of the above-mentioned stand. The substrate temperature control method described in 1.

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