KR20030080973A - Thermal treatment unit with removing capability of particles generated by filter - Google Patents

Abstract

Particles generated from the packing portion of the clean oven are processed without being put into the heat treatment chamber to maintain their cleanliness well.

In the clean oven, the filter 3 is attached to the inlet frame 1 via the packing 2, and the filter 3 is passed through the circulation path 5 of the gas for heat treatment provided with the blower 4. To the heat treatment chamber (6), and has an outlet frame (7) for capturing the gap portion (71) generated on the interior side of the packing, and a weight mechanism (8) through the suction side of the blower (4). .

From the outlet frame 7 and the peripheral frame 31 of the filter 3, the indoor gas always enters the gap portion 71, passes through the circulation path 5 from the weight mechanism 8, and is sucked into the blower 4. When the packing 2 oscillates due to the stress received at the time of lifting temperature, it is discharged from the gap portion and does not enter the tank, thereby maintaining the cleanliness of the room.

Description

Heat treatment device with filter oscillation treatment {THERMAL TREATMENT UNIT WITH REMOVING CAPABILITY OF PARTICLES GENERATED BY FILTER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment apparatus in which a filter is attached to a structural member via a sealing member to pass a fraud filter through a circulation path of a gas for heat treatment having a blower so that the gas is put into a heat treatment chamber. It is suitably used as a heat treatment apparatus for heat-treating electrical and electronic parts including semiconductor products such as liquid crystal glass substrates that need to be heat-treated under environmental conditions at a high temperature.

Semiconductor products, such as liquid crystal glass substrates, need to minimize the generation of particles that are minute dust on the basis of their quality. Therefore, when heat treatment, heat treatment is performed through a high-performance filter commonly referred to as a HEPA filter in a thermostat called a clean oven. Dragon air is supplied to the heat treatment chamber.

As a result, as shown in FIG. 8, in the conventional apparatus having a heat treatment temperature of about 300 ° C., during a temperature increase operation from a preheating temperature of about 100 ° C. to a heat treatment temperature of about 300 ° C. (T ₁ ) And the number of particles of the particles at 300 ° C constant temperature operation (T ₂ ) after the temperature rise was set to 100 or less, and first, the required cleanliness was satisfied. In addition, the said 100 pieces are the number of particle | grains whose particle diameter is 0.5 micrometer or more in the volume of ¹ cf (ft3) (about 28 liters) in a heat processing chamber.

However, recently, high heat treatment temperatures of about 500 ° C. have been manufactured as production lines for electronic parts and for test and research clean ovens, and it has been found that the cleanliness of the heat treatment chambers has not been satisfied in such clean ovens. .

That is, in such a clean oven, in order to shorten a process time, the speed at the time of temperature rise may be made into 2 times 8-10 degrees C / min from the conventional 4-5 degrees C / min, and heat processing temperature itself is high temperature. At the same time, as the temperature increase rate is increased, as shown in the drawing of the conventional clean oven of FIG. 6, in the temperature increase and decrease process, between the periphery frame 31 of the high performance filter 3 and the inlet frame 1 of the clean oven. In the part of the packing 2 which is interposed in the part, the difference in thermal deformation of both frames arises, and as shown in the packing 2, the compressive force P, the width direction, and the longitudinal direction (direction perpendicular to the ground in the drawing) External force in which the shear force T, etc. fluctuate, is applied, and compressive stress, shear stress, and deformations accompanying them occur, and various packings such as those in which glass fibers are fixed with a binder are oscillated, whereby arrows (A Particles in the heat treatment chamber (6) It turned out that total particle number exceeded the target value.

According to the experiments of the inventors and the like, as shown in FIG. 7, the number of particles issued at the time of raising the temperature and lowering the temperature of the sample air collected at the center of the heat treatment chamber with respect to the heat treatment temperature (410 ° C.) was 0.3. More than 100 micrometers or more resulted in the failure to obtain the target cleanliness.

Therefore, an object of the present invention is to solve the above problems in the prior art and to provide a heat treatment apparatus capable of reducing the amount of particles entering the heat treatment chamber and maintaining the cleanliness of the heat treatment chamber satisfactorily.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which shows an example of the whole structure of the clean oven which is a heat processing apparatus to which this invention is applied.

2 is an explanatory diagram showing measurement results of particles in operation of the clean oven;

3 is an explanatory diagram showing another example of the overall configuration of the clean oven;

4 is an explanatory diagram showing still another example of the overall configuration of the clean oven;

5 is an explanatory diagram showing still another example of the overall configuration of the clean oven;

6 is an explanatory diagram showing an example of the overall configuration of a conventional clean oven for high temperature;

7 is an explanatory diagram showing measurement results of particles in high temperature operation of the clean oven; and

Fig. 8 is an explanatory diagram showing the cleanliness in a laboratory at the time of program operation of a clean oven at a conventional normal heat treatment temperature.

(Explanation of the sign)

1: entrance frame (structural member) 2: packing (sealing member)

3: filter 4: blower

5: circulation path 6: heat treatment chamber

7: Outlet frame (membrane member)

8: weight mechanism (gap gas extraction means, gap gas introduction means)

11: exhaust port (gap gas extraction means) 12: exhaust pipe (gap gas extraction means)

13 exhaust fan (gap gas extraction means) 71: gap part

82, 83: pipes (gap gas extraction means, gap gas introduction means)

84: reverting blower (gap gas extraction means, gap gas introduction means)

100: clean oven (heat treatment device)

SUMMARY OF THE INVENTION In order to solve the above problems, the invention of claim 1 attaches a filter to a structural member via a sealing member to pass the filter through a circulation path of a gas for heat treatment provided with a blower to heat the gas. In the heat treatment apparatus to put in,

And a partition member for partitioning the gap portion formed on the heat treatment chamber side from the heat treatment chamber, including the sealing member, and a gap gas extracting means for extracting gas from the gap portion.

According to a second aspect of the present invention, in addition to the above, the gap gas extracting means is a gap gas introducing means for allowing gas in the gap portion to be introduced into the circulation path.

According to a third aspect of the present invention, in addition to the above, the gap gas introducing means enables the gas to be introduced into the suction side of the blower in the circulation path.

Embodiment of the Invention

1 shows a configuration example of a clean oven as a heat treatment apparatus to which the present invention is applied.

The clean oven 100 includes a filter 2 attached to the inlet frame 1 as a structural member via a packing 2 as a sealing member, and a circulation path 5 for heat treatment gas having a blower 4. A device for allowing gas to be introduced into the heat treatment chamber 6 by passing through the filter 3 from the filter chamber, the outlet frame 7 serving as the partition member, the gap gas ejection means, and the weight mechanism for introducing the gap gas. Take-out port) 8; The heat treatment chamber 6 and the circulation path 5 are surrounded by a casing 101 serving as an inner wall surface of the heat insulation wall, and the heaters 9 for heat treatment are arranged in the circulation path 5.

Moreover, the clean oven of this invention is for the high temperature which can heat up to 500 degreeC, The cooler 1 for indoor quenching (it became switchable with the damper not shown) is provided. As the gas circulated for the heated heat treatment, it is used in correspondence to an object or heat treatment temperature for which nitrogen-enriched air or the like is heat treated as air or an inert gas atmosphere.

The periphery of the filter 3 is surrounded by the periphery frame 31, and the circulating gas passes through the center portion except for the edge portion 31a as shown by the arrow. The packing 2 is provided between the inlet frame 1 corresponding to the entire circumference of the edge 31a of the peripheral frame.

The outlet frame 7 is comprised so that the clearance gap 71 which arises in the heat processing chamber 6 side containing the packing 2 may be partitioned from the heat processing chamber 6. That is, since the packing 2 seals between the heat treatment chamber 6 and the portion of the circulation path 5 on the inlet side, a gap portion also occurs on the heat treatment chamber 6 side. In this example, the gap portion 71 is formed. Silver, the edges 31a of the periphery 31 of the packing 2, the inlet frame 1 directly in contact with the filter 3, the periphery 31, the casing 101 of the clean oven 100 And a partition plate 102 between the heat treatment chamber 6 and the circulation path 5, and the like, around the upper and lower left and right portions of the filter 3, and the outlet frame 7 is enclosed so as to partition the portion. have. Therefore, although this part and the heat processing chamber 6 are not airtight, the conduction part is narrow.

In addition, the partition member does not necessarily need to be provided at the position of the outlet frame 1 shown in FIG. 1, and may be a member which can narrow the partition part as long as it partitions the clearance part which contains the packing 2. As shown in FIG.

The weight mechanism 8 is a gap gas extracting means which allows the gas in the gap portion 71 to be blown out and is an introduction means. In this example, the gas in the gap portion is blown out of the blower 4 in the circulation path 5. It is formed to introduce to the suction side. That is, in the clean oven 100 of this example, a part of the gap portion 71 is formed on the partition plate 102 side, and the part faces the suction side of the blower 4, so that the gap gas is taken out and introduced. The weight mechanism 8 which consists of a simple opening is made into the simplest structure.

In addition, you may provide the slide plate 81 which has the squeeze function shown by the dashed-two dotted line so that the magnitude | size of this part may be adjusted. By doing so, the amount of return gas to the blower suction side can be adjusted, and particles generated from the packing 2 can be sucked with a minimum amount of gas with a considerable probability.

The clean oven 100 as described above is operated as follows and exerts its effect.

In the heat treatment chamber 6, as shown by the dashed-dotted line in the drawing, a substrate W made of a liquid crystal glass substrate or the like as an object to be heat-treated is stacked in multiple stages in a cassette 200 having a frame assembly structure. Is put in. Then, the blower 4 and the heater 9 are operated to circulate the gas such as air or the nitrogen-enriched gas, whose concentration is adjusted, from the circulation path 5 through the heat treatment chamber 6 via the filter 3. Moreover, when heat processing is complete | finished, operation | movement of the heater 9 is stopped and the cooler 10 is operated.

In this manner, the temperature in the heat treatment chamber 6 during the operation is normally controlled by the program. That is, in this operation, for example, as shown in Figs. 2 and 7, the substrate W at the heat treatment temperature after the preheating up to about 100 ° C., the temperature rise to the heat treatment temperature from about 400 ° C., and the temperature increase is reached. Heating, cooling to a temperature of about 200 ° C. or lower, and the like are performed under an appropriate elevation temperature and temperature holding time.

When the heating gas is circulated in this manner, at the time of the temperature increase and the temperature decrease, the state of the temperature change is determined by the differences in shape, dimensions, heat capacity, or estimated amount of gas in each device or member constituting the heat treatment apparatus. In addition, since these members are made of a stainless steel material, a material suitable for each part is selected, and since the types thereof are different, and the coefficient of thermal expansion is also significantly different, the deformation amounts are different, and the relative displacement in each part is different. Occurs.

As a result, in the part of the packing 2, an uneven deformation occurs between the inlet frame 1 and the peripheral frame 31 of the filter 3 in contact with the packing 2, and the packing 2 has a compressive force or a shear force as described above. And the like, stresses and deformations corresponding thereto occur, and the microcomponents become particles from the packing 2 and scatter.

At this time, in the apparatus of this example, since the weight mechanism 8 is provided for the gap portion 71, in the gap portion 71, the gas therein is always sucked into the blower in the circulation path 5 from the heat treatment chamber 6. When gas flows to the side and particles are generated, it flows out of the gap portion 71 through the penetrating mechanism 8 by the gas flow, is sent out to the blower 4, and passes through the filter 3 again. . As a result, the particles are captured by the filter 3. And it is not discharged | emitted from the clearance part 71 to the heat processing chamber 6 side.

FIG. 2 shows the results of the operation test of the clean oven 100 as described above and the generation of particles.

The clean ovens used in this test are of the following specification.

Substrate treatment type; Batch

Processing capacity; 20 sheets / 1 time

Maximum heat treatment temperature; 500 ℃

Heater output; 54.6 W

Filter type; Heat-resistant special filter

Packing material; Inorganic fiber

The size of the weight mechanism 8; 80 mm x 4

This clean oven is the same as that of the operation result shown in FIG. 7 except for having the weight mechanism 8. According to the measurement results of Figs. 2 and 7, from the conventional structure does not install the estimation mechanism 8 is, in the above particle diameter 0.3㎛ particles, the temperature was raised during 1cf (T ₁₎ and the temperature decrease during (T ₃₎ The weight mechanism 8 of the present example to which the present invention was applied was provided in that 50 particles were largely exceeded, and 50 particles having a particle diameter of 0.5 μm or more were close to 50, and a large number of particles having a particle diameter of 1.0 μm or more were also provided. In one apparatus, even if the particle size is 0.3 µm or more, the number thereof is 50 or less, and the number of particles decreases to about half or less in the case of FIG.

In these operations of FIGS. 2 and 7, the temperature-fall rate when quenching using the cooler 11 without introducing a temperature increase rate and outside air together is about 8 ° C./min, and the conventional normal temperature shown in FIG. 8 is shown. The temperature increase rate at the operation of about 6 ° C./min was 1.3 times or more, and the amount of particles generated was increased. In the apparatus of this example, the number of particles in the laboratory was sufficiently low as described above. . Therefore, according to the apparatus of FIG. 1 to which the present invention is applied, even in a clean oven having a rapid elevating temperature, under the extremely simple configuration, the amount of particles fed into the heat treatment chamber 6 can be reduced and the cleanliness can be maintained in a good state. . In addition. At the normal heat treatment temperature, the cleanliness can be lowered to a more relaxed low level.

In addition, since the clearance gap between the peripheral frame 31 of the filter 3 and the exit frame 7 is made small in the clearance part 71, the weight mechanism 8 of the comparatively large diameter of 80 mm is provided. The gas flow rate passing through was about 2 to ^{3 m 3} / mm, which was sufficiently small at about 3 to 5% of the amount of circulating air. Therefore, even if such a gas return system is provided, it does not affect the performance of a clean oven.

3 shows another example of a clean oven to which the present invention is applied.

In the present example, the blower 4 is arranged upstream of the position of the weight mechanism 8, and the pipe 82 is introduced from the weight mechanism 8 to the suction side. The point is different. Also in this example, the same effects as those in FIG. 1 can be obtained.

4 shows another example of a clean oven to which the present invention is applied.

In this example, since the blower 4 is spaced apart from the position of the weight mechanism 8 shown in FIG. 1, FIG. 3, the gas of the clearance part 71 of the blower 4 in the circulation path 5 is carried out. Since it is difficult to return to the suction side, the weight mechanism 8 is provided in the upper casing 101, the pipe 83 and the return blower 84 are arranged, and the gas in the gap portion 71 is circulated. It is made to return to the upstream side of the middle filter 3. As shown in FIG. In this example, a return blower 84 is required, which is good enough to have a small capacity, so that the influence on power consumption and device cost is slight.

5 shows another example of a clean oven to which the present invention is applied.

In this example, the gas in the gap portion 71 is not returned to the circulation path 5 once more, and the exhaust port 11 and the exhaust pipe 12 are disposed in the upper casing 101 similarly to the apparatus of FIG. ), And the pipe is further extended from the clean room or the clean room where the clean oven is usually installed to be discharged to the outside atmosphere. In addition, since the inside of the heat treatment chamber 6 has a constant pressure to some extent, no gas flows in from the outside, but in order to exhaust the gas more completely, the exhaust blower 13 is provided as shown by the dashed-dotted line in the drawing. You may also Similarly, the exhaust blower may have a small capacity.

According to the apparatus of this example, since a gas suitable for the amount emitted as the circulating gas is blown in, a slight but heat loss occurs. However, in heat-treatment objects such as liquid crystal glass substrates, there may be a case where the ventilation is always performed due to a decrease in concentration of a sublimable gas generated in a photoresist or various solvents used for circuit formation on the substrate. It is also possible to use the exhaust from the weight mechanism 8 as part of such a venting gas.

According to the present invention as described above, in the invention of claim 1, the filter is attached to the structural member of the heat treatment apparatus via a sealing member, and the gas is passed through the filter from the circulation path of the gas for heat treatment provided with the blower. In the heat treatment apparatus to be put in the heat treatment chamber, a partition member is formed in which the gap portion formed on the heat treatment chamber side including the sealing member is partitioned from the heat treatment chamber, thereby preventing free conduction of gas between the gap portion and the heat treatment chamber. .

And since the gap gas extraction means which makes it possible to take out the gas of a gap part is provided, a small amount of gas enters from the heat processing chamber by which the partition member was partitioned from the gap part, and the gas of a gap part can be taken out. That is, the gap portion can be ventilated.

On the other hand, since the gap portion includes a sealing member, when the heat treatment apparatus is operated and the operating state is a temperature raising process or a temperature lowering process, the structural member of the heat treatment apparatus or the structural member of the filter are unequally deformed and various stresses and deformations are applied to the sealing member. The particle | grain which is a dust component is produced | generated from a sealing member, and it enters into a clearance part. At this time, since the gap portion can be ventilated as described above, such particles can be removed from the gap portion in accordance with the ventilation. As a result, the cleanliness in the heat treatment chamber can be improved. Further, the semiconductor product or the like, which requires a cleaning environment, can be heat treated satisfactorily in an environment of acceptable cleanliness.

In the invention of claim 2, the gap gas extracting means is a gap gas introducing means which allows gas to be introduced into the circulation path, so that the gas can be passed through the filter again into the heat treatment chamber. As a result, particles generated in the packing and entering the gap portion can be captured by the filter. Then, the heat treatment chamber can be maintained in a clean environment. In this case, since the gas taken out from the gap portion is recovered by the circulation path, thermal loss does not occur and there is no need to supply gas. As a result, the particles generated during packing can be processed by a simple structure without affecting the thermal efficiency of the heat treatment apparatus.

In the invention of claim 3, the gap gas introduction means is configured to allow gas to be introduced into the suction side of the blower in the circulation path, so that the gas in the gap portion can be returned to the circulation path by the suction force of the blower. . As a result, in addition to the above-described effects, it is possible to have an extremely simple structure such that a conduction port that conducts with the suction side of the blower is provided or a pipe for conducting conduction is provided in the gap portion.

Claims (3)

A heat treatment apparatus in which a filter is attached to a structural member via a sealing member, and the filter is passed through a circulation path of a gas for heat treatment provided with a blower to put the gas into the heat treatment chamber. And a partition member for partitioning the gap portion formed on the heat treatment chamber side from the heat treatment chamber, including the sealing member, and a gap gas extracting means for ejecting gas from the gap portion. The heat treatment apparatus according to claim 1, wherein the gap gas extracting means is a gap gas introducing means which allows gas in the gap portion to be introduced into the circulation path. 3. The heat treatment apparatus according to claim 2, wherein the gap gas introduction means enables the gas to be introduced into the suction side of the blower in the circulation path.