JPH10312943A - Temperature controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly control the temperature of an object to be controlled for temperature, such as the wafer, etc., to a desired temperature by performing temperature control with a high heat-exchanging efficiency. SOLUTION: A temperature controller is provided with supporting plates 2 and 3 which support an object to be controlled for temperature, a temperature control chamber 4 provided so that its top face 5 comes into contact with the lower surfaces of the plates 2 and 3, a plurality of fluid-jetting holes 6 which jet a fluid against the top internal surface of the ceiling of the chamber 4, fluid-supplying means 9, 10, and 11 which supply a fluid adjusted to a prescribed temperature to the holes 6, fluid-discharging means 13 and 14 which discharge the fluid jetted from the holes 6 from the chamber 4, and an optically heating heater means 20 which heats the internal surface of the ceiling of the chamber 4 by using light energy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a temperature control device for controlling the temperature of a temperature controlled object such as a wafer.

[0002]

2. Description of the Related Art A semiconductor manufacturing process includes a heating process (prebaking) for removing a solvent remaining in a resist film applied to a wafer,
It includes a heating step (post-baking) to facilitate the adhesion between the resist and the substrate before etching, and a cooling step to cool the heated wafer to room temperature. It is important to efficiently and accurately control the temperature to increase the throughput, and various types of temperature control have conventionally been employed.

As a prior art of this kind, Japanese Patent Application Laid-Open No. Sho 62-4
No. 5121 is known. This prior art is employed in a photoresist removing apparatus that removes a photoresist that masks a wafer into a predetermined pattern, and a heater is mounted under a susceptor on which the wafer is mounted so that the wafer can be heated and UV lamps are arranged above these wafers. Further, a rotatable dispersion head having a large number of oxygen gas ejection holes is provided above the ultraviolet lamp, and oxygen gas is supplied in a shower shape from above the wafer.

That is, in this conventional technique, oxygen gas supplied in a shower is excited by an ultraviolet lamp to generate ozone, and the photoresist on the wafer surface is separated from the wafer surface by the ozone gas, and the photoresist is discharged to the outside through an exhaust nozzle. I try to exhaust.

However, in this conventional technique, the temperature control of the wafer is performed only by the heater provided on the wafer mounting table (susceptor). Therefore, when cooling the wafer temperature, it is necessary to rely on natural heat radiation. Controlling the wafer at a predetermined temperature involves accuracy and speed problems.

Another conventional technique is disclosed in
There is one disclosed in JP-A-169330. This prior art relates to temperature control of a wafer or a mask in transferring a photomask pattern onto a wafer in a semiconductor exposure apparatus, and a heater and a temperature detector are provided in a chamber defined below a wafer support (wafer chuck). And a cooling air is circulated in a chamber defined below the wafer support. According to this conventional configuration, heating is performed by the heater, and cooling is performed by flowing cooling air, so that both the heater and the wafer support having surplus heat can be cooled by the cooling air.

However, in this prior art, the cooling process is performed by circulating cooling air through a chamber defined below the wafer support, and the heating process is performed by a heater. There is a problem that the exchange efficiency is poor and it takes time for the wafer to reach a predetermined temperature.

Another prior art is disclosed in Japanese Patent Application Laid-Open No.
There is one disclosed in Japanese Patent Publication No. 1308. This prior art relates to a wafer temperature control device in an X-ray exposure apparatus, in which a plurality of Peltier elements, a heat pipe, and a cooling block are sequentially stacked under a wafer support (suction block), and heat is quickly diffused by the heat pipe. The temperature is controlled by the Peltier element while the temperature is controlled.

However, in this prior art, temperature control is basically performed by a Peltier element, so that the controllable temperature range is limited, and heat exchange efficiency and durability are poor.
When the temperature range to be controlled is wide, there is a problem that it takes time to reach a desired temperature of the wafer and that the life of the Peltier element is short.

The present invention has been made in view of such circumstances, and provides a temperature control apparatus for quickly and accurately controlling a temperature controlled object such as a wafer to a desired temperature by temperature control with good heat exchange efficiency. The purpose is to provide.

The present invention also relates to a temperature control in which there are a plurality of different target values for temperature control in a wide temperature range and the target values are periodically moved between the plurality of different target values. It is an object of the present invention to provide a temperature control device capable of quickly and accurately controlling the temperature to the plurality of target values.

[0012]

According to the present invention, there is provided a support plate for supporting an object to be temperature-controlled, a temperature control chamber provided so that an upper wall surface thereof is in contact with a lower portion of the support plate, and A plurality of fluid ejection holes for ejecting a fluid to the upper inner wall surface of the temperature control chamber, a fluid supply means for supplying a fluid adjusted to a predetermined temperature to these fluid ejection holes, and a plurality of fluid ejection holes. A fluid discharging means for discharging the ejected fluid from the temperature control chamber, and a light heating type heater means for heating an upper inner wall surface of the temperature control chamber using light energy are provided. .

According to the invention, the temperature is controlled to a predetermined temperature by ejecting the fluid adjusted to a predetermined temperature to the upper inner wall surface of the fluid ejection chamber disposed below the support plate for supporting the temperature control object. The temperature of the object is controlled, and the upper inner wall surface of the fluid ejection chamber is heated in a non-contact manner by a heater means of a light heating system using light energy in a near-infrared light region or a visible light region. That is, the temperature of the temperature control target is controlled by performing heat exchange between the temperature control target and the upper wall surface of the fluid ejection chamber via the support plate.

Therefore, according to the present invention, the heat exchange efficiency can be increased as compared with the prior art, and the temperature controlled object can be quickly controlled to a desired temperature.

[0015]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

In the semiconductor manufacturing process, the resist film
Usually, a film is formed through the following process.

(1) Wafer cleaning (2) Resist coating (3) Pre-bake + cooling (4) Exposure (5) Development (6) Rinsing (7) Post-bake + cooling (8) Etching Here, in the pre-bake step, Baking temperature is 9
The temperature is set to 0 ° C. to 200 ° C. (depending on the process), and the target temperature is set to, for example, a room temperature of about 20 ° C. in the cooling step performed after the pre-bake step.

In the post-baking step, the baking temperature is set at 100 ° C. to 250 ° C. (depending on the process). In the cooling step performed after the post-baking step, the target temperature is set to, for example, 20 ° C.
The room temperature is set to about ゜ C.

Since the next step of the pre-bake step is exposure and the next step of the post-bake step is etching, the temperature distribution of the wafer is quite severe in order to be able to shift to these steps immediately. Conditions are required.

The temperature control device of the embodiment shown below is used in the pre-bake + cooling step or the post-bake + cooling step. First, the wafer is heated to a high temperature (baking step), and then the wafer is heated to about room temperature. (Cooling step) is repeated at intervals of several tens of seconds for each wafer. That is, in this case, there are two target temperatures, that is, a target temperature for heating and a target temperature for cooling, and heating and cooling are repeated alternately.

1 to 3 show an embodiment of the present invention.

In FIG. 1, a wafer 1 is supported by a heat dissipation / absorption plate 2. The heat releasing / absorbing plate 2 is made of a material having a high thermal conductivity (aluminum or copper), and is provided so that heat exchange with the wafer 1 is performed uniformly over the entire surface of the wafer 1. A heat panel 3 is provided below the heat release / absorption plate 2. The heat panel 3 is formed with a plurality of communicating spaces in which a working fluid having a good thermal conductivity is enclosed. When the heat transfer between the ceiling surface 5 of the temperature control chamber 4 and the wafer 1 is improved, the heat panel 3 is released. It is provided to make the temperature distribution of the heat absorbing plate 2 and the wafer 1 uniform.

Upper wall 5 constituting the ceiling of temperature control room 4
The region 5a on which the heat panel 3 is mounted is made of a material having a high thermal conductivity (aluminum or copper), while the other region 5b is made of a material having a poor heat transfer coefficient. As a result, heat is efficiently transmitted between the upper wall surface 5 and the heat panel 3.

A plurality of fluid ejection nozzles 6 are provided in the temperature control chamber 4, and a low-temperature liquid 8 is supplied to the plurality of fluid ejection nozzles 6 via a supply pipe 7.
One or a plurality of small ejection holes are formed in the fluid ejection nozzle 6 so that the shower-like high-speed low-temperature liquid 8 is supplied to the temperature control chamber 4.
To the upper inner wall surface 5 constituting the ceiling of FIG.

The supply pipe 7 has a valve 9, a liquid supply path 10,
The pump 11, the chiller 12, the fluid discharge path 13, and the discharge port 14 of the temperature control chamber 4 are connected.

That is, the low-temperature liquid 8 adjusted to a predetermined low-temperature by the chiller 12 is supplied to the fluid ejection nozzle 6 through the pump 111, the valve 9, and the supply pipe 7, and the upper inner wall surface of the temperature control chamber 4 is formed. 5 is hit. Thereafter, the low-temperature liquid 8 is discharged to the fluid discharge path 13 through the discharge port 14 and then supplied to the chiller 12 to be re-cooled. The low-temperature liquid 8 recooled by the chiller 12 is recirculated to the valve 9 by the pump 11.

Here, as the low-temperature fluid 8 ejected from the fluid ejection nozzle 6, a liquid having a light transmitting property and an insulating property, for example, Fluorinert (registered trademark) is used. Note that water or ethylene glycol may be used as the low-temperature fluid 8 depending on the temperature level.

The temperature control chamber 4 may be opened by providing an opening (not shown) or may be closed. When the temperature control chamber 4 is hermetically sealed, the jet stream is jetted from the jet nozzle 6 to the temperature control chamber 4 filled with fluid, so that the fluid jet nozzle 6 → the temperature control chamber. 4 upper wall 5 →
A forced convection that flows through the discharge port 14 is generated, and the upper wall 5 of the temperature control chamber 4 is cooled by the forced convection.

When the temperature control chamber 4 is opened, the low-temperature fluid collides with the upper inner wall surface 5 through the space, so that the flow velocity of the jet flow increases and the temperature control chamber has a ceiling. Only a new fluid will always collide, and heat exchange will be performed promptly.

Next, the temperature control chamber 4 is provided with a plurality of light heating type heaters 20 for heating the wafer 1 (directly on the upper wall surface 5 of the temperature control chamber 4). These light heating type heaters 20 are, for example, halogen heaters,
The light (mostly near-infrared light) emitted from the halogen lamp 23 is used as heat. As the heater 20 of the light heating type, a heater using a lamp that generates light energy in the near-infrared light region or visible light region having a good light-to-heat conversion rate is mainly used.

As shown in FIG. 2, the light heating type heater 20 includes a base holder 21, a reflector mirror 22, a circular halogen lamp 23, a water cooling tube 24, and a lid made of a light-transmitting material. The light heating type heaters 20 are arranged between rows of the fluid ejection nozzles 6 as shown in a plan view in FIG.

In this case, the light heating type heater 20 has a water cooling tube 24 through which a low-temperature liquid such as water flows, and cooling is performed while the lamp is turned on, so that the temperature rise of the heater unit itself is suppressed. And the deterioration of the reflector mirror 22 can be prevented.

In this case, the light heating type heater 20 is used.
Is attached to the supply pipe 7 through which the low-temperature fluid passes through the base holder 21, so that the same operation and effect as the water cooling pipe 24 can be obtained. Therefore, the water cooling pipe 24 provided in the heater unit may be omitted. Further, depending on the operation state of the heater 20, even when the heater 20 is not attached to the supply pipe 7, the water cooling pipe 24 may be omitted.

In this case, an insulating liquid is used as the low-temperature fluid 8, but in consideration of safety,
The inside of the light heating type heater 20 is isolated from the outside by a lid cover 25. Of course, if safety is ensured, the lid cover 25 may be omitted.

In this configuration, the temperature of the wafer is set to 15
The operation in the case where the temperature is controlled alternately at 0 ° C. and 20 ° C. at intervals of several tens of seconds will be described. That is, a baking step performed at a wafer temperature of 150 ° C. and a cooling step of cooling the wafer temperature to 20 ° C. are alternately performed.

First, the wafer 1 on which the resist has been applied is carried in and placed on the heat-dissipating / absorbing plate 2 at very small intervals, and the lamp 23 of each heater 20 is turned on. The heat radiated from each heater 20 is transmitted to the wafer 1 via the upper wall surface 5 of the temperature control chamber 4, the heat panel 3, and the heat radiation / absorption plate 2.

The temperatures of the upper wall surface 5, the heat panel 3, the heat-dissipating and absorbing plate 2 of the temperature control chamber 4 are detected by a sensor (not shown), and the temperature of the wafer 1 is set to a target temperature of 150 ° based on the detected temperature. C is controlled.

As described above, the wafer temperature is set to 125 ° C.
When the baking step performed by heating the wafer to the end is completed, a cooling step of cooling the wafer temperature to 20 ° C. is executed.

First, the valve 9 is opened, and a low-temperature fluid having a temperature of about 20 ° C. is supplied from the chiller 12 to the supply pipe 7.
The low-temperature fluid supplied to the supply pipe 7 is jetted and ejected through the fluid ejection nozzle 6. The jetted low-temperature fluid collides with the upper inner wall surface 5 of the temperature control chamber 4.
Due to the collision of the fluid, the heat transfer coefficient of the upper inner wall surface 5 increases, and the upper surface of the upper wall surface 5 in contact with the heat panel 3 can be brought close to the temperature of the low-temperature fluid at high speed.

That is, in this case, the heat of the wafer 1 is radiated through the heat releasing / absorbing plate 2, the heat panel 3, and the upper wall surface 5 of the temperature control chamber, thereby cooling the wafer 1. During this cooling, the upper wall 5 of the temperature control chamber 4
The temperature of the heat panel 3 and the heat release / absorption plate 2 is detected by a sensor (not shown), and the temperature of the wafer 1 is controlled to a target temperature of 20 ° C. based on the detected temperature.

As described above, when the cooling step of the wafer 1 is completed, the wafer 1 is carried out of the apparatus, and a new wafer 1 coated with a resist is carried in. Instead, the wafer 1 is heated and cooled in the same manner as described above. You.

According to the above embodiment, heating of the upper wall surface 5 of the temperature control chamber 4 is performed by non-contact heating from the inside of the temperature control chamber 4 by the light heating type heater 20, and the cooling is performed by the temperature control chamber 4 from the temperature control chamber 4. Since the low-temperature liquid is ejected to the upper inner wall surface 5, a rapid thermal response can be made when switching from heating to cooling or from cooling to heating, and the temperature of the wafer 1 can be quickly controlled to a desired temperature. can do.

When a liquid having a high light transmittance such as florinate is used as the low-temperature fluid 8, the temperature control chamber 4 in a closed state is filled with the low-temperature fluid 8, or the lid of the light heating heater 20 is closed. Even if the low-temperature fluid 8 remains on the cover 25, the lamp 2 of the light-heated heater 20
3 can irradiate the upper wall surface 5 of the temperature control chamber 4 without blocking the light.

When an insulating liquid such as florinate is used as the low-temperature fluid, the light heating type heater 20 is not isolated from the outside by the cover 25 or the like, and is placed in the temperature control chamber 4 in which the low-temperature fluid 8 flows. It becomes possible to arrange.

Further, according to the above embodiment, the low temperature fluid 8
Since the light-heating type heater unit is attached to the supply pipe 7 through which the air flows, the temperature rise of the heater unit itself can be suppressed, and the deterioration of the reflection plate mirror 22 can be prevented.

In the above embodiment, the heat panel 3 is used as a heat energy transfer means for transferring heat energy between the upper wall surface 5 of the temperature control chamber 4 and the heat release / absorption plate 2. A Peltier element may be used instead of the heat panel 3. Further, both the heat panel and the Peltier device may be used as the thermal energy transfer means. At this time, the vertical relationship between the heat panel and the Peltier element is arbitrary. Further, one of the heat release / absorption plate 2 and the heat panel 3 may be omitted. Further, the heat release / absorption plate 2 and the heat panel 3 may be omitted, and the wafer 1 may be directly supported on the upper wall surface 5 of the temperature control chamber 4.

In the above embodiment, the fluid ejection nozzle 6
The light-heating type heater 20 is arranged between the rows, but as shown in FIG. 4, the light-heating type heater 20 is located below the supply pipe 7 for supplying the low-temperature fluid to the fluid ejection nozzle 6.
May be arranged. In this case, the fluid ejection nozzle 6, the supply pipe 7, and the like need to be made of a light-transmissive transparent material. When the light heating type heater 20 is disposed below the fluid ejection nozzle 6 and the supply pipe 7, a spiral low-temperature fluid supply pipe 30 as shown in FIG. 5 may be formed. In this case, a number of fluid ejection holes 31 are dispersedly arranged in the spiral low-temperature fluid supply pipe 30.

As shown in FIG. 6, the low-temperature fluid jet nozzle 6 may be arranged in the temperature control chamber 4 so as to generate a tornado-shaped swirling flow. According to such a swirling flow nozzle, since it has a speed component in the swirling direction in addition to the speed component in the upward direction, the temperature control is performed in comparison with the nozzle of the embodiment of FIG. Since it comes into contact with the side surface and the ceiling of the chamber 6 for a long time, the heat exchange efficiency can be further increased.

Further, as shown in FIG. 7 (a), the low-temperature fluid jet nozzles 6 may be arranged so that the disposition angles thereof are alternately turned one by one in a reverse oblique direction. As shown in FIG. 7, a plurality of rows of low-temperature fluid jet nozzles 6 may be arranged between the respective light-heated heaters 20. Further, as shown in FIG. The ejection nozzles 6 may be arranged such that the arrangement angles are alternately turned one by one in the reverse oblique direction.

Further, as shown in FIG. 8A, the wall surface of the reflection plate mirror 22 of the light heating type heater 20 and the tube wall surface of the low-temperature fluid jet nozzle 6 may be shared. in this case,
Since the contact area increases, the cooling effect of the light heating type heater 20 by the low temperature fluid passing through the low temperature fluid ejection nozzle 6 is improved.

As shown in FIG. 8 (b), a light heating type heater 2 made of a material such as plastic or aluminum is used.
The light heating type heater 20 and the fluid ejection nozzle 6 are arranged by dropping the light heating type heater 20 into the concave portion of the fluid ejection nozzle unit 40 which is formed into a curved surface so as to correspond to the shape of the reflector mirror 22 of 0. It may be. In this case, similarly to FIG.
0 and the light heating type heater 20
Positioning becomes easy. Further, since the fluid ejection nozzle portion 6 is formed into a curved surface, the pressure loss of the flow of the low-temperature fluid is reduced, and a high-speed jet stream can be ejected even at a lower pump water pressure.

In FIG. 8B, the lid cover 25 of the light heater 20 is also connected to the fluid ejection nozzle unit 4.
0 may be integrally molded. In this case, the fluid ejection nozzle unit 40 must use a transparent material such as plastic, acrylic, or polycarbonate.

In the above embodiment, the tubular lamp 23 is used as the light heater 20. However, a plurality of lamps having a spherical shape may be arranged in a matrix. Further, as a material of the fluid ejection nozzle, a metal such as aluminum, stainless steel, copper, or a plastic material is used. Further, the shape of the fluid ejection hole in the fluid ejection nozzle 6 may be any shape such as a circle, a slit, or a rectangle. In addition, the fluid ejection nozzle 6 of the above embodiment is used as a mist nozzle to generate mist-like fluid. Thus, the turbulence effect may be obtained to improve the heat transfer capability. Further, a perforated plate made of a light-transmitting material may be provided above the mist nozzle of the temperature control chamber 4 to further improve the turbulence effect. Furthermore, the turbulence effect may be further enhanced by roughening the surface of the inner wall surface 5 by providing irregularities or the like, providing protrusions, or shaving the upper inner wall surface 5 of the temperature control chamber 4.

If the intervals between the fluid ejection nozzles 6 are made close to each other, the divergent jet stream ejected from one nozzle and the jet stream ejected from the nozzle adjacent thereto overlap with each other, thereby controlling the temperature. This is further advantageous in improving the temperature uniformity of the upper wall surface 5 of the chamber 4. That is, since the fluid jetted from the nozzle 6 has a mountain-shaped flow velocity spatial distribution, the flow velocity distribution is made uniform over the entire upper wall surface 5 of the temperature control chamber 4 by overlapping the skirts of the mountain. It is.

In the above embodiment, the wafer 1 is cooled by supplying the low-temperature fluid through the fluid ejection nozzle 6. However, when only the object to be temperature-controlled needs to be heated, A high-temperature fluid for heating may be supplied to the fluid ejection nozzle 6. In this case, the object to be temperature-controlled can be heated at a higher speed by the synergistic effect of the heating by the ejection of the high-temperature fluid and the heating by the light heater 20.

Further, the present invention can be applied to a temperature controlled object other than a semiconductor wafer.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a side view showing a specific configuration example of a light heating type heater.

FIG. 3 is a plan view showing an arrangement of a light heating type heater and a fluid ejection nozzle.

FIG. 4 is a diagram showing a modification of the embodiment.

FIG. 5 is a diagram showing a modification of the embodiment.

FIG. 6 is a diagram showing a modification of the embodiment.

FIG. 7 is a diagram showing a modification of the embodiment.

FIG. 8 is a diagram showing a modification of the embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Wafer 2 ... Heat release / absorption plate 3 ... Heat panel 4 ... Temperature control room 5 ... Upper wall surface 6 ... Fluid ejection nozzle 7 ... Fluid supply pipe 8 ... Low temperature fluid 9 ... Valve 10 ... Fluid supply path 11 ... Pump 12 ... Chiller 13 ... Fluid discharge path 14 ... Discharge port 20 ... Light heating type heater 21 ... Base unit 22 ... Reflector mirror 23 ...
Lamp 24: Cooling tube 25: Lid cover

Claims (6)

[Claims] A support plate for supporting an object to be temperature-controlled, a temperature control chamber provided so that an upper wall surface thereof is in contact with a lower portion of the support plate, and a fluid with respect to an upper inner wall surface of the temperature control chamber. A plurality of fluid ejection holes for ejecting fluid, fluid supply means for supplying a fluid adjusted to a predetermined temperature to the fluid ejection holes, and discharging the fluid ejected from the plurality of fluid ejection holes from the temperature control chamber. A temperature control device, comprising: a fluid discharge unit that performs heating, and a light heating type heater unit that heats an upper inner wall surface of the temperature control chamber using light energy. 2. The temperature control device according to claim 1, wherein the fluid is a liquid having a light transmitting property and an insulating property. 3. The temperature control device according to claim 1, wherein said heater means generates light energy in a near-infrared light region or a visible light region. 4. The temperature control device according to claim 1, wherein said fluid supply means supplies a low-temperature fluid for cooling said temperature control object to said plurality of fluid ejection holes. 5. The fluid supply means has a low-temperature fluid supply pipe for supplying a low-temperature fluid to the fluid ejection hole in the temperature control chamber, and the light heating type heater means is attached to the low-temperature fluid supply pipe. The temperature control device according to claim 4, wherein 6. The fluid supply means includes a low-temperature fluid supply pipe for supplying a low-temperature fluid to the fluid ejection hole in the temperature control chamber, and the low-temperature fluid supply pipe is made of a light-transmitting material. The temperature control device according to claim 4, wherein