JPH07260210A - Thermal chamber - Google Patents

Abstract

PURPOSE:To provide a thermal chamber, capable of realizing agitation of atmosphere sent out of a cooling device simply and inexpensively whereby capable of unifying the temperature distribution in a testing chamber with a high accuracy. CONSTITUTION:A thermal chamber is constituted of an atmosphere regulating chamber 13, effecting the temperature regulation of atmosphere in a testing chamber 12 effecting measurement and the like, a cooling device 14, cooling the atmosphere sucked from the testing chamber 12 and discharging the atmosphere into an atmosphere regulating chamber 14 and a heating device 16 heating the atmosphere sent out of the cooling device 14. A hood 15, covering the outlet port of the cooling device 14 and equipped with the proper number of discharging ports 19, 20, 21, discharging the atmosphere, sent out of the cooling device 14, into mutually different directions in the atmosphere regulating chamber 13, is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal chamber that provides a constant temperature space suitable for measuring minute dimensions and the like, and more particularly to improving the constant temperature performance.

[0002]

2. Description of the Related Art Recently, a high-precision measuring instrument capable of submicron measurement has been required for measuring the line width of semiconductor integrated circuits and inspecting wafers.
Along with such a tendency, a high-precision measuring instrument using a laser microscope has been attracting attention.

In order to realize such highly accurate measurement, it is essential to secure a clean constant temperature space free of dust and the like, and it is important to improve the performance of the thermal chamber that provides this constant temperature space. Bring meaning. FIG. 5 shows a schematic configuration of the conventional thermal chamber 1. The thermal chamber 1 includes a test chamber 2 which is a space used for measurement and the like, and an atmosphere (usually air) in the test chamber 2 is sucked in to adjust the temperature to a predetermined temperature and then returned to the test chamber 2. An atmosphere adjusting chamber 3 for uniformizing the temperature distribution in the test chamber 2 is provided.

In the atmosphere adjusting chamber 3, a cooling device 4 is installed near the entrance of the atmosphere adjusting chamber 3 to cool the atmosphere sucked from the test chamber 2 and blow it out into the atmosphere adjusting chamber 3. A heating device 5 arranged downstream of the cooling device 4 for performing a predetermined heat treatment on the atmosphere blown out from the cooling device 4, and the atmosphere heat-treated by the heating device 5 is pressure-fed to the test chamber 2 side. It is equipped with a fan 6. A filter 7 for removing dust and the like from the atmosphere returned to the test chamber 2 is provided on the outlet side of the fan 6.
Is equipped with. The arrows in the figure show the flow of the atmosphere in the thermal chamber 1.

That is, in the thermal chamber 1, for example, the main part 8 of a laser microscope as a measuring instrument is the test chamber 2
Is installed in. The atmosphere in the test chamber 2 is circulated back through the cooling device 4 and the heating device 5 so that the room temperature does not change during measurement due to heat generated on the measuring instrument side.

By the way, in the structure of such a thermal chamber 1, the temperature distribution in the test chamber 2 has a gradient (in the direction orthogonal to the paper surface in FIG. 5) of the blowout by the cooling device 4 and the fan 6. That is, temperature variations) are likely to occur. In order to reduce such a temperature gradient and make the temperature distribution more highly uniform, it is effective to make the temperature distribution on the outlet side of the cooling device 4 uniform. Therefore, it has been studied so far to provide a diffuser plate (louver) such as a punching plate or an auxiliary fan on the outlet side of the cooling device 4 or to actively agitate. Came.

[0007]

However, the provision of the diffusion plate such as the punching plate can improve the effect of blurring the temperature boundary in the test chamber 2, but the temperature change in the entire room. There is a problem that it is ineffective in reducing the width. In addition, when the auxiliary fan is installed, the stirring effect is high, but since the fan itself becomes a heat source and exerts a new influence, it is necessary to make fine adjustments to the temperature adjustment by the cooling device 4 and the heating device 5. However, there is a problem that the device cost and the operating cost are high.

[0008] Therefore, an object of the present invention is to solve the above-mentioned problems, and the stirring of the atmosphere blown out from the cooling device can be realized simply and at low cost, thereby making the temperature distribution in the test chamber uniform with higher accuracy. It is possible to provide a thermal chamber capable of exhibiting a high constant temperature performance suitable for measurement of minute dimensions.

[0009]

The thermal chamber of the present invention is, as a means for solving the problems, a test chamber providing a space used for measurement and the like, and a predetermined temperature adjustment by sucking the atmosphere in the test chamber. And an atmosphere adjusting chamber for uniformizing the temperature distribution in the test chamber by returning to the test chamber, and in the atmosphere adjusting chamber, the test is installed near the entrance of the atmosphere adjusting chamber. A cooling device that cools the atmosphere sucked from the chamber and blows it out into the atmosphere adjustment chamber, and a heating device that is arranged downstream of the cooling device and performs a predetermined heat treatment on the atmosphere blown out from the cooling device are provided. In the thermal chamber
The outlet side of the cooling device was equipped with an appropriate number of outlets that cover the outlet port of the cooling device and let the atmosphere blown out of the cooling device flow out in different directions in the atmosphere adjusting chamber. It features a hood.

As means for solving the problems,
The discharge port of the hood has a variable opening area for letting out an atmosphere.

Further, as a means for solving the problems, the hood is characterized in that the discharge ports are formed at three positions on both sides and a central part in the blowing width direction of the cooling device. .

[0012]

According to the above-mentioned structure of the present invention, the atmosphere blown out from the cooling device has a plurality of outlets of the hood arranged on the outlet side of the cooling device in which the flow velocity is increased and the flow directions are different from each other. Of the cooling device is discharged into the atmosphere adjusting chamber and is agitated by the collision of the plurality of air currents in the atmosphere adjusting chamber with each other to promote the agitation and to make the temperature distribution in the test chamber uniform. A uniform temperature distribution on the side is achieved.

Moreover, the hood may have a simple structure in which an appropriate number of openings serving as discharge ports are formed in a wall plate of a sheet metal casing covering the blow-out port of the cooling device. It can be obtained at low cost.

The opening area of the discharge port of the hood is
It is preferable to adjust the size according to the size of the atmosphere adjusting chamber or the test chamber. However, if the opening area of the discharge port is variable in advance as described in claim 2, the optimum opening area can be easily adjusted. It can be adjusted.

Further, according to a third aspect of the present invention, the configuration in which the discharge ports of the hood are set at three positions on the left and right sides and the center which are separated in the blowing width direction of the cooling device is blown out from the cooling device. It is excellent in that it divides the atmosphere into a plurality of air streams with greatly different blowing directions to promote agitation, and at the same time it is excellent in simplifying the structure of the hood as much as possible, achieving two issues in a well-balanced manner. be able to.

[0016]

1 and 2 show one embodiment of the thermal chamber according to the present invention. The thermal chamber 10 of this embodiment is a space 1 used for measurement and the like.
1 and the temperature distribution in the test chamber 12 is uniform by sucking the atmosphere (usually air) in the test chamber 12 to adjust the temperature to a predetermined temperature and then returning the temperature to the test chamber 12. And an atmosphere adjusting chamber 13 for changing the atmosphere.

In the atmosphere adjusting chamber 13, the test chamber 1 is installed near the entrance of the atmosphere adjusting chamber 13.
The cooling device 14 that cools the atmosphere sucked from 2 and blows it into the atmosphere adjusting chamber 13, and the atmosphere that the cooling device 14 blows out is different from each other in the atmosphere adjusting chamber 13. And a hood 15 that is disposed downstream of the hood 15 (downstream in consideration of the circulation direction of the atmosphere).
A heating device 16 that performs a predetermined heat treatment on the atmosphere blown from the chamber, and a fan 17 that pressure-feeds the atmosphere heated by the heating device 16 to the test chamber 12 side are provided.

A filter 18 for removing dust and the like from the atmosphere returned to the inside of the test chamber 12 is provided on the outlet side of the fan 17. The arrows in the figure
The flow of the atmosphere in the thermal chamber 10 is shown. That is, in the thermal chamber 10 of this embodiment, for example, the main part 8 of the laser microscope as a measuring instrument is installed in the test chamber 12. Then, the atmosphere in the test chamber 12 is set to the cooling device 14 and the heating device 16 so that the room temperature does not change during measurement due to heat generation on the measuring instrument side.
Is circulated and returned through the filter 18.

The cooling device 14 corresponds to, for example, an evaporator of a refrigerator, and cools a passing atmosphere by a predetermined amount. Further, in the case of this embodiment, the hood 15 is a housing made of sheet metal and is installed on the outlet side of the cooling device 14 to cover the outlet of the cooling device 14 as shown in FIG. , The cooling device 14
The discharge ports 19, 20, 21 are provided at three positions on both sides and the center of the blowout width direction (direction orthogonal to the paper surface in FIG. 1).
It is equipped with.

The above-mentioned discharge ports 19, 20, and 21 are provided for discharging the atmosphere blown out from the cooling device 14 in different directions in the atmosphere adjusting chamber 13, and are provided in the central portion of the housing. The discharge port 19 is slidably equipped with a shutter plate 23 for adjusting the opening area of the discharge port 19. The shutter plate 23 is slidably attached to the wall portion of the housing by a known guide mechanism, and the air flow to be discharged from the discharge port 19 according to the size of the atmosphere adjusting chamber 13 or the test chamber 12 or the like. It is used when adjusting the flow velocity and flow rate of.

In the case of the hood 15 of this embodiment, the discharge ports 20 and 21 provided on both left and right sides of the housing are not provided with shutter plates 23 for adjusting the opening area. However, these discharge ports 20 and 21 are formed at the upper and lower positions, and the opening area can be adjusted by, for example, closing one of them with a blind plate. Specifications of measuring instruments installed in the test room 12 and the test room 12
If the specifications of the atmosphere adjusting chamber 13 have already been determined, and if the control temperature in the test chamber 2 required at the time of measurement has also been determined, the opening area of each of the discharge ports 19, 20, 21 is set appropriately. It is advisable to tentatively perform a trial operation with the values, measure the temperature distribution in the test chamber 12 at that time, and correct the opening areas of the discharge ports 19, 20, 21 according to the results.

The fan 17 blows the temperature-controlled atmosphere through the cooling device 14, the hood 15, and the heating device 16 into the entire area of the test chamber 12 by pressure in a substantially uniform manner so that the temperature of the atmosphere is controlled. Three units are arranged at appropriate intervals along (that is, in the width direction of the test chamber 12) (see FIG. 2).

The thermal chamber 10 of the above embodiment
Then, the atmosphere blown out from the cooling device 14 is increased by the respective discharge ports 19, 20, 21 of the hood 15 provided on the outlet side of the cooling device 14, and the flow velocity is increased and the flow directions are different from each other (the center is The airflow is changed into one airflow and two airflows on each of the left and right sides and is discharged into the atmosphere adjusting chamber 13, and the agitation is promoted by the collision of these five airflows in the atmosphere adjusting chamber 13, and the test is performed. Since the temperature distribution on the outlet side of the cooling device 14, which is the key to the uniform temperature distribution in the chamber 12, is achieved, the temperature distribution in the test chamber 12 can be made more highly uniform. Therefore, it becomes possible to obtain a high-level constant temperature performance suitable for measurement of minute dimensions. In the experiment actually conducted by the inventor of the present application, the maximum temperature difference was ± 0.5 ° C. or more in the temperature distribution in the test chamber 12 when the hood 15 was not attached, whereas the hood 15 was attached. In this state, the maximum temperature difference in the temperature distribution in the test chamber 12 can be suppressed to about ± 0.1 ° C, and it is confirmed that the hood 15 exhibits an excellent effect of uniforming the temperature distribution. Was done.

Moreover, the hood 15 may have a simple structure in which a proper number of openings serving as discharge ports are formed in the wall plate of the casing made of sheet metal that covers the blow-out port of the cooling device 14, as in the embodiment. It is possible to achieve the purpose easily, inexpensively. Further, the opening area of the discharge port of the hood 15 should be adjusted according to various conditions such as the size of the atmosphere adjusting chamber 12 and the test chamber 13 or the amount of heat generated by the measuring instrument installed in the test chamber 12 and the test contents. However, if the opening area is preliminarily variable by the slidable shutter plate 23 like the discharge port 19 of the embodiment, it is possible to easily adjust the opening area to the optimum one and improve the handling. Therefore, it is possible to improve versatility.

Further, the discharge ports 19, 20, 2 of the hood 15
1 is set at three positions, that is, the left and right side portions and the central portion, which are separated from each other in the blowing width direction of the cooling device 14,
It is excellent in that the atmosphere blown out of the hood 15 is divided into a plurality of air currents whose blowing directions are largely different to promote stirring, and at the same time, it is also excellent in simplifying the structure of the hood 15 as much as possible, and the temperature is kept constant easily and inexpensively. It greatly contributes to the achievement of the purpose of improving performance.

The atmosphere in the test chamber 12 is as follows.
Although it is usually air, it is needless to say that, for example, an inert gas atmosphere may be used, and the gas or the like forming the atmosphere can be appropriately changed depending on the sample installed in the test chamber 12 or the test content. Yes.

Further, the shape of the hood 15, the equipment position and the number of equipment of the discharge port, the size of the discharge port opening, the material and the like are as follows.
It is not limited to the above-mentioned embodiment. For example, in the case of the above-described embodiment, the hood 15 includes the cooling device 14.
The side walls are provided so as to face each other in the width direction of the blowout, and the discharge ports 20 and 21 are opened on the side walls.
Further, as shown in FIG. 4, the side walls may be eliminated, and the side walls may be provided with the discharge ports 24 and 25 which are opened greatly. Also,
The opening shape of the discharge port is not limited to the quadrangular shape in the embodiment, and may be, for example, a semi-cylindrical shape such as the discharge port 26 shown in FIG. 3 or the discharge port 27 shown in FIG. The design can be changed appropriately, such as a semicircular shape. Further, the entire shape of the hood 15 is not limited to the rectangular parallelepiped box shape shown in the embodiment, and for example, as shown in FIG. 4, the wall plate providing the central discharge port 27 is formed into an arc shape. It may have a curved shape.

Although the hood 15 is made of sheet metal in the above embodiment, it may be made of a synthetic resin material. Further, the test chamber 12 of the thermal chamber 10 of the one embodiment has been described as being used for measurement of a minute dimension by a laser microscope or the like.
The use of No. 2 is not limited to that of one embodiment,
It can be used for various applications requiring high constant temperature performance.

[0029]

According to the thermal chamber of the present invention,
The atmosphere blown out from the cooling device is converted into a plurality of air streams having a higher flow velocity and different flow directions by each discharge port of the hood provided on the blower port side of the cooling device, and is discharged into the atmosphere adjusting chamber. The agitation is promoted by the collision of the plurality of air flows in the atmosphere adjusting chamber, and the temperature distribution on the outlet side of the cooling device, which is the key to the uniform temperature distribution in the test chamber, is uniformized. For,
It is possible to make the temperature distribution in the test chamber uniform with higher accuracy, and to obtain a high-level constant temperature performance suitable for measurement of minute dimensions. Moreover, the hood may have a simple structure in which an appropriate number of discharge openings are formed in the wall plate of the housing made of sheet metal that covers the blow-out opening of the cooling device, and can be easily and inexpensively obtained. Therefore, the purpose can be achieved easily and inexpensively. Also,
The opening area of the discharge port of the hood is preferably adjusted according to the size of the atmosphere adjustment chamber or the test chamber, etc., but as described in claim 2, the opening area of the discharge port is variable beforehand. If so, it is possible to easily adjust to the optimum opening area, and it is possible to improve the handleability and the versatility. Further, as described in claim 3, the configuration in which the outlets of the hood are set at three positions, that is, the left and right side portions and the central portion which are separated in the blowing width direction of the cooling device, blows out the atmosphere blown out from the cooling device. It is excellent in that it divides into a plurality of air streams whose directions are greatly different to promote stirring, and at the same time it is excellent in simplifying the structure of the hood as much as possible, and it is possible to achieve two issues in a well-balanced manner.
It greatly contributes to the achievement of the purpose of easily and inexpensively improving the constant temperature performance.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an embodiment of the present invention.

FIG. 2 is a perspective view of a main part of an embodiment of the present invention.

FIG. 3 is a perspective view showing another embodiment of the main part of the present invention.

FIG. 4 is a perspective view showing still another embodiment of the main part of the present invention.

FIG. 5 is a vertical cross-sectional view of a conventional thermal chamber.

[Explanation of symbols]

 10 Thermal Chamber 11 Space 12 Test Room 13 Atmosphere Control Room 14 Cooling Device 15 Hood 16 Heating Device 17 Fan 18 Filter 19, 20, 21, 21, 25, 26, 27 Discharge Port

Claims (3)

[Claims] 1. A test chamber for providing a space used for measurement and the like, and a temperature distribution in the test chamber is made uniform by sucking the atmosphere in the test chamber, adjusting a predetermined temperature, and then returning to the test chamber. An atmosphere adjusting chamber, and a cooling device installed in the atmosphere adjusting chamber near the entrance of the atmosphere adjusting chamber to cool the atmosphere sucked from the test chamber and blow it out into the atmosphere adjusting chamber; In a thermal chamber provided downstream of the apparatus and provided with a heating device for performing a predetermined heat treatment on an atmosphere blown out from the cooling device, a blowing port of the cooling device is provided on a blowing port side of the cooling device. A hood equipped with an appropriate number of outlets that covers the mouth and causes the atmosphere blown out of the cooling device to flow out in different directions in the atmosphere adjusting chamber. Thermal chamber, characterized in that. 2. The thermal chamber according to claim 1, wherein the discharge port of the hood has a variable opening area for letting out an atmosphere. 3. The thermal chamber according to claim 1, wherein the hood is formed with the discharge ports at three locations on both sides and a central portion in a blowing width direction of the cooling device.