KR100835018B1 - Pulsation reducing apparatus and inspection apparatus - Google Patents

Abstract

The present invention relates to a pulsation alleviation device and an inspection device. The pulsation alleviation apparatus of the present invention is connected to a first tank for storing a refrigerant while leaving a space portion, and to replenish the refrigerant in the first tank 15A while being connected to the first tank at a position higher than the first tank. A gas withdrawal piping connecting the tank and the space portion of the first tank 15A and the replenishment tank 15B is provided. According to the present invention, it is possible to provide a pulsation alleviation device and an inspection device that can reliably and reliably alleviate pulsation at all times even if the liquid vaporizes.

Description

Pulsation Reduction Device and Inspection Device {PULSATION REDUCING APPARATUS AND INSPECTION APPARATUS}

1 is a block diagram conceptually showing an inspection apparatus to which the pulsation alleviation apparatus of the present invention is applied;

2 is a configuration diagram showing a first pulsation alleviation device of the inspection device shown in FIG. 1;

FIG. 3 is a configuration diagram showing a second pulsation reducing device of the inspection device shown in FIG. 1. FIG.

Explanation of symbols for the main parts of the drawings

10: inspection device 11: mounting table (expectation)

13: pump 15: first pulsation alleviation device

15A: first tank 15B: supplement tank

15C: Degassing pipe 15D: Relief valve

16: 2nd pulsation reducing device 16A: 2nd tank

16B: first liquid level sensor 16C: second liquid level sensor

16D: Air Control Unit 16G: First Valve

16H: second valve

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulsation reducing device and an inspection device, and more particularly, to a pulsation reducing device and a pulsation which reduce vibrations of a base due to pulsation when a liquid such as a heat medium is circulated in the base using a pump. A test apparatus provided with a reducing device.

Conventionally, for example, a diaphragm type, a bladder type, a bellows type or the like has been put into practical use as a pulsation alleviation device. However, all of these systems have a high initial set pressure and are difficult to operate smoothly in a low pressure region or negative pressure. Moreover, all of these systems have high spring constants for buffering pulsations and cannot absorb minute pulsations. In addition, neither method can be used in relation to the material strength in a low temperature region of, for example, minus tens of degrees. There is also a gas pressurized pulsation reducing device, but the liquid level in the tank is caused by the inclusion gas dissolved into the liquid, gas separation from the liquid such as vaporization of the liquid or vaporization of the dissolved gas, or a change in the pressure of the circulating fluid. It is difficult to keep it constant.

In addition, Patent Document 1 (Japanese Patent Application Laid-Open No. 6-403383) discloses a water level control device for an air chamber that reduces pulsation in a manner completely different from those described above. The water level control device of the air chamber lengthens the interval of air replenishment of the air chamber in the reciprocating pump, reduces the labor of air replenishment, reduces labor, and enables long-term stable operation and stable operation. It is aimed at being able to. In the case of this apparatus, an air chamber such as an intake air chamber in which air is sealed is used as a main chamber, and in this main chamber, a water level adjusting pipe obtained by letting out the liquid inside by overflow is provided, and in this water level adjusting pipe, Connect the auxiliary chamber with air enclosed. Initially, the pulsation damping, cushioning, and capacity compensation functions normally without the liquid flowing out of the level control tube. Gradually, however, when air is dissolved and consumed as a liquid and the water level rises, the liquid overflows the level control pipe and flows out into the auxiliary chamber, and the air is extruded by this liquid, and the main chamber is replaced and replenished, so that the minimum amount of air required for a long time. Capacity is secured.

However, in the case of the pulsation reducing device described in Patent Literature 1, in the positive pressure piping on the discharge side of the pump, the main chamber is arranged at a high position of the auxiliary chamber, and air is dissolved into the main chamber to assist the increased liquid. By overflowing the chamber and replacing the liquid lost by overflowing with the air in the auxiliary chamber, the pressure rise due to vaporization of the liquid in the main chamber is not assumed. For example, when the object to be processed is cooled on a mounting table such as an inspection device for a processing object such as a semiconductor wafer, and the object to be processed at the time of inspection is kept at a constant temperature, a refrigerant circulating in the mounting table is main. It is easy to vaporize in a chamber, and the vaporization capacity of a liquid exceeds the dissolution capacity, such as air to liquid, the pressure of the gas in a main chamber rises, and a pulsation reduction function is impaired.

This invention is made | formed in order to solve the said subject, Comprising: It aims at providing the pulsation reduction apparatus and inspection apparatus which can always reliably and reliably reduce a pulsation even if a liquid vaporizes.

The pulsation reducing device according to an aspect of the present invention is used in a device having a pump for circulating a liquid in a base and a tank for storing a liquid circulating through the pump, the space on the liquid level in the tank. In the device for reducing the pulsation of the liquid by the pump by using the gas in the portion as a buffer, the tank has a refill tank for storing the liquid so that the liquid level of the refill tank is higher than the liquid level in the tank. When the tank and the space portion of the replenishment tank are connected via a gas degassing pipe, and the liquid in the tank is reduced so that the space portion in the tank and the space portion in the replenishment tank communicate with each other through the gas degassing pipe, The gas in the tank is drawn out through the gas bleed pipe into the space in the replenishment tank and The liquid in the tank to supplement group wherein the supplement into the tank.

In the pulsation alleviation device according to this aspect, it is preferable to provide the tank and the replenishment tank on the suction side of the pump, respectively.

Moreover, in the said pulsation alleviation apparatus, it is preferable to provide the relief valve which opens the space part to air | atmosphere by the pressure of the gas in the said replenishment tank.

A pulsation alleviation device according to another aspect of the present invention is used in an apparatus having a pump for circulating a liquid in a base, and a tank for storing a liquid circulating through the pump. In the device for reducing the pulsation of the liquid by the pump as a buffer, a first liquid level sensor for detecting the upper liquid level upper limit of the liquid in the tank and a second liquid level sensor for detecting the lower liquid level lower limit of the liquid in the tank, respectively The height of the liquid level in the said tank is controlled in a predetermined range based on the detection signal of the said 1st, 2nd liquid level sensor.

In the pulsation alleviation device according to the present aspect, a first valve for introducing gas into the tank based on a detection signal of the first liquid level sensor is provided, and the inside of the tank is based on a detection signal of the second liquid level sensor. It is preferable to provide a second valve for exhausting the gas.

Moreover, in the said pulsation alleviation apparatus, it is preferable to provide the control apparatus which opens and closes and controls the said 1st, 2nd valve based on the detection signal of the said 1st, 2nd liquid level sensor.

In addition, in the pulsation alleviation apparatus according to the first aspect of the present invention, the liquid is preferably a heat medium whose vapor pressure is higher than the pressure difference due to the difference in the liquid level between the tank and the refill tank.

An inspection apparatus according to another aspect of the present invention includes a mounting table on which a target object is to be mounted, a pump for circulating liquid in the mounting table, and a tank for storing liquid circulating through the pump. An inspection apparatus for inspecting an object to be treated, comprising: at least one pulsation reducing device for reducing the pulsation of the liquid by the pump, using a gas in the space portion on the liquid level in the tank as a buffer; will be.

In the inspection apparatus according to this aspect, it is preferable to have the pulsation alleviation apparatus according to the first aspect of the present invention described above and / or the pulsation alleviation apparatus according to the second aspect of the present invention described above.

Further, in the inspection apparatus according to the present aspect, it is preferable that the liquid is a thermal medium whose vapor pressure is higher than the pressure difference caused by the difference in the liquid level between the tank and the refill tank.

On the other hand, the inspection apparatus according to another aspect of the present invention includes a mounting table on which the object to be processed is mounted, a pump for circulating the liquid in the mounting table, a tank for storing the liquid circulating through the pump, An inspection apparatus for inspecting an object to be processed on the mounting table, characterized in that a pulsation alleviation device for reducing the pulsation of the liquid by the pump is provided at least on the suction side of the liquid of the pump.

In the inspection apparatus according to this aspect, it is preferable to provide at least one pulsation reducing device for reducing pulsation of the liquid by the pump, using a gas in the space portion on the liquid level in the tank as a buffer.

Further, in the inspection apparatus according to this aspect, the pulsation alleviation device preferably has a pulsation alleviation device according to the first aspect of the present invention and / or a pulsation alleviation apparatus according to the second aspect of the present invention. Do.

Further, in the inspection apparatus according to the present aspect, it is preferable that the liquid is a thermal medium whose vapor pressure is higher than the pressure difference caused by the difference in the liquid level between the tank and the refill tank.

(Example)

Hereinafter, this invention is demonstrated based on embodiment shown to FIGS. 1-3. 1 is a block diagram conceptually showing a test apparatus to which the pulsation reducing device of the present invention is applied, FIG. 2 is a configuration diagram showing a first pulsation reducing device of the test apparatus shown in FIG. 1, and FIG. 3 is a test shown in FIG. 1. It is a block diagram which shows the 2nd pulsation alleviation apparatus of an apparatus. In each figure, the arrow shown by the solid line shows the flow of a refrigerant | coolant, and the arrow shown by the broken line shows the flow of gas.

As shown in FIG. 1, for example, the inspection apparatus 10 according to the present embodiment includes a mounting table 11 on which a treatment body (for example, a semiconductor wafer) W is mounted, a mounting table 11, and a circulation pipe. The pump 13 which is connected via (12) and supplies and circulates a coolant to the mounting table 11, and the refrigerant | cooled after temperature which circulates the circulation pipe 12 from the mounting table 11 via the pump 13 The heat exchanger 14 which cools to the original temperature is comprised, and it is comprised so that the semiconductor wafer W on the mounting table 11 may be cooled by a refrigerant | coolant, and the electrical property inspection of the semiconductor wafer W may be carried out at predetermined temperature. . The mounting table 11 is moved in the horizontal direction and the vertical direction in order to contact the semiconductor wafer W and the probe card (not shown) at the time of inspection.

The mounting table 11 is cooled by a coolant, and, for example, the electrical characteristics of the semiconductor wafer W can be inspected at an appropriate temperature within a range of minus tens of degrees to an image of 150 ° C. As the refrigerant used at this time, for example, a fluorine-based inert liquid (Fluorinert (trade name) manufactured by Sumitomo SriM Corporation, Galden (trade name) manufactured by Solvay Solexis, Inc., etc.) may be used. have.

When the refrigerant is circulated by the pump 13, the mounting table 11 and the circulation pipe 12 vibrate slightly due to the pulsation of the refrigerant. The vibration of the mounting table 11 affects the contact pressure between the semiconductor wafer W and the probe card, which may adversely affect the inspection of the semiconductor wafer W. The influence of pulsation is remarkable so that the integrated circuit formed in the semiconductor wafer W becomes dense and the wiring layer and the insulating layer become thin. Therefore, in this embodiment, in order to reduce the pulsation by the pump 13, the 1st, 2nd pulsation reduction apparatus 15, 16 is provided in the circulation piping 12. As shown in FIG. The first pulsation reducing device 15 is disposed on the negative pressure side that sucks the refrigerant by the pump 13, and the second pulsation reducing device 16 is disposed on the positive pressure side that discharges the refrigerant from the pump 13. It is.

For example, as shown in FIG. 2, the first pulsation alleviating device 15 is arranged in the circulation pipe 12, like the first tank 15A for storing the refrigerant while leaving a space, and the first tank 15A. A replenishment tank 15B, which is connected to the circulation pipe 12 and stores a replenishment refrigerant to the first tank 15A, leaving a space portion, is provided so that gas such as air in the space portion of the first tank 15A reduces pulsation. It is configured to act as a buffer.

The replenishment tank 15B is disposed at a position where the liquid level is higher than that of the first tank 15A. As described later, the refrigerant in the first tank 15A vaporizes to increase the pressure in the space portion, and at the same time, the amount of liquid decreases, thereby reducing the liquid level. When this falls, the refrigerant is replenished into the first tank 15A, and the liquid level of the refrigerant in the first tank 15A is kept constant.

That is, 15 A of 1st tanks and 15 B of replenishment tanks are connected through 15C of gas releasing piping. The connection part with 15 A of 1st tanks of the gas discharge piping 15C is normally located in the refrigerant slightly below the space part, and the connection part with the replenishment tank 15B of the gas discharge piping 15C is always located in the space part. . For this reason, the space part of the 1st tank 15A and the space part of the replenishment tank 15B are normally interrupted | blocked. However, when the refrigerant in the first tank 15A vaporizes, the amount of liquid decreases, and the pressure of the space portion increases, the liquid level of the refrigerant decreases, and the liquid level reaches the connection with the gas releasing pipe 15C. The space portion of 15A) and the space portion of the replenishment tank 15B communicate with each other, and the gas in the first tank 15A moves to the space portion of the replenishment tank 15B, so that the pressure of the space portion of the replenishment tank 15B increases.

A relief valve 15D is attached to the space portion of the replenishment tank 15B, and the relief valve 15D automatically opens the space portion to the atmosphere when it exceeds a predetermined pressure (for example, 0.1 kg / cm ² G). The gas (including the vaporized refrigerant) in the replenishment tank 15B is discharged to the atmosphere side. When the pressure of the space portion in the replenishment tank 15B decreases due to the release of gas, the relief valve 15D is automatically closed. At this time, since the replenishment tank 15B is disposed at a position higher than the first tank 15A, the replenishment tank 15B has a hydraulic pressure difference between the refrigerant in the first tank 15A and the refrigerant in the replenishment tank 15B. The refrigerant is replenished in the first tank 15A, the liquid level in the first tank 15A is returned to its original state, the connection portion with the gas bleed pipe 15C is sealed, and the first tank 15A and the replenishment tank 15B are filled. To block the space.

In addition, the 2nd pulsation reducing apparatus 16 is connected to the circulation pipe 12, for example, as shown in FIG. 3, The 2nd tank 16A which saves a refrigerant | coolant, leaving a space part, and the 2nd tank 16A. Detection signals from these sensors 16B and 16C that are electrically connected to the first and second liquid level sensors 16B and 16C and the first and second liquid level sensors 16B and 16C that detect the liquid level of the refrigerant in the chamber. And an air control device 16D operating on the basis of the air control device, and the gas such as air filling the space part of the second tank 16A acts as a buffer to reduce pulsation when discharging the refrigerant from the pump 13. Consists of.

An air pipe 16E is connected to the second tank 16A. As described later, the air tank 16A is introduced into the second tank 16A through the air pipe 16E and the second tank 16A is introduced. The gas inside is discharged to the outside. That is, the pressure regulator valve 16F, the 1st, 2nd valve 16G, 16H are sequentially arrange | positioned in the air piping 16E toward the downstream side, and a predetermined pressure is supplied to dry air by the regulator valve 16F. And dry air is introduced into the second tank 16A via the first and second valves 16G and 16H to be discharged. The branch pipe which connects the air piping 16E and the 2nd tank 16A is provided between the 1st, 2nd valve 16G, 16H. The branch pipe 16I is provided in this branch pipe, and the flow volume of the air which flows through a branch pipe by the barley 16I is restrict | limited. Both the first and second valves 16G and 16H are electrically connected to the air control device 16D and open and close under the control of the air control device 16D.

The first liquid level sensor 16B transmits a detection signal to the air control device 16D when the liquid level in the second tank 16A rises to reach an upper limit and detects the liquid level. The air control device 16D opens the first valve 16G based on the detection signal of the first liquid level sensor 16B, and supplies dry air into the second tank 16A via the air pipe 16E and its branch pipe. It is introduced and pressurized to lower the liquid level of the refrigerant. The second liquid level sensor 16C transmits a detection signal to the air control device 16D when the liquid level in the second tank 16A falls to the lower limit and detects the liquid level. The air control device 16D opens the second valve 16H based on the detection signal of the second liquid level sensor 16C, and discharges the gas in the second tank 16A via the branch pipe and the air pipe 16E. The pressure is reduced, and the liquid level of the refrigerant is raised.

Therefore, the air control device 16D opens and closes the first and second valves 16G and 16H based on the detection signals of the first and second liquid level sensors 16B and 16C, and the inside of the second tank 16A. The liquid level of the refrigerant is kept constant by keeping the gas pressure of the space portion constant. In addition, 16J is a communication pipe which communicates the refrigerant | coolant part and space part in 16A of 2nd tanks, and the 1st, 2nd liquid level sensors 16B, 16C are provided in this communication pipe 16J.

Next, the operation will be described. When inspecting the semiconductor wafer W, the pump 13 is driven to circulate the refrigerant at a constant flow rate in the mounting table 11 to cool the mounting table 11. Since the mounting table 11 is cooled, it cools even if the semiconductor wafer W on it heats at the time of inspection, and is maintained at predetermined temperature. The refrigerant pulsates when the refrigerant is sucked in and discharged by the pump 13, but in the present embodiment, the first and second pulsation reducing devices 15 and 16 act to reduce the pulsation, whereby the mounting table 11 And vibration of the circulation pipe 12 can be suppressed and prevented, and the reliability of the inspection can be improved.

That is, when the pump 13 drives and draws in refrigerant | coolant, when refrigerant | coolant passes the 1st tank 15A of the 1st pulsation alleviation apparatus 15, gas, such as air of the space part in the 1st tank 15A, buffers It becomes a sieve and reduces the pulsation on the suction side of the pump 13. Further, when the refrigerant is discharged from the pump 13, the refrigerant passes through the circulation pipe 12, passes through the heat exchanger 14, where the refrigerant is cooled, and then the second tank 16A of the second pulsation reducing device 16 is cooled. Go through). When the refrigerant passes through the second tank 16A, gas such as air in the space portion of the second tank 16A becomes a buffer and reduces the pulsation on the discharge side of the pump 13.

In this way, even if the refrigerant pulsates due to the suction and discharge operation of the refrigerant by the pump 13, the pulsation on the suction side is reduced by the first pulsation reducing device 15 and discharged by the second pulsation reducing device 16. In order to reduce the side pulsation, the vibration by the pulsation of the mounting table 11 and the circulation pipe 12 can be suppressed or prevented especially, and the reliability of the inspection of the semiconductor wafer W can be improved.

However, if the inspection is continued, in the first pulsation alleviation device 15, the refrigerant vaporizes by the action of the negative pressure of the pump suction pressure in the first tank 15A, and the refrigerant gradually decreases and the space is gradually reduced. Negative pressure rises and liquid level falls. When the liquid level of the refrigerant falls in the first tank 15A and reaches the connection portion with the gas bleed pipe 15C, the space portion of the first tank 15A and the space portion of the replenishment tank 15B communicate with each other. Since the space portion of the first tank 15A has a higher pressure than the space portion of the refill tank 15B, the gas in the first tank 15A moves to the space portion in the replenishment tank 15B, so that the space of the replenishment tank 15B The pressure in the space portion rises.

In the replenishment tank 15B, the relief valve 15D is operated to open the space portion to the atmosphere side, and at the same time release the gas in the space portion and replenish the refrigerant to the first tank 15A. By the release of gas, the pressure in the space portion in the replenishment tank 15B is lowered, and the relief valve 15D is closed. As a result, the refrigerant is replenished from the replenishment tank 15B into the first tank 15A due to the difference in the liquid level between the refrigerant in the replenishment tank 15B and the refrigerant in the first tank 15A. In the first tank 15A, the liquid level rises, returns to the initial liquid level, seals the connection with the gas bleed pipe 15C, blocks the supplement tank 15B, and continues the normal pulsation-reducing action.

In addition, in the second pulsation reducing device 16, the gas dissolves in the refrigerant under the action of the positive pressure of the pump discharge pressure in the second tank 16A as opposed to the first pulsation reducing device 15. When the liquid level of the refrigerant rises due to the dissolution of gas in the second tank 16A, and the first liquid level sensor 16B detects the liquid level, the air control device 16D returns from the first liquid level sensor 16B. The first valve 16G is opened based on the detection signal, and dry air is introduced into the second tank 16A from the air pipe 16E to lower the liquid level. When the liquid level returns to its original state and the detection signal from the first liquid level sensor 16B disappears, the air control device 16D closes the first valve 16G and stops the introduction of dry air.

In addition, even when the discharge amount of the pump 13 varies, the liquid level of the refrigerant in the second tank 16A varies. When the discharge amount increases and the liquid level of the refrigerant rises in the second tank 16A, and the first liquid level sensor 16B detects the liquid level, the air control device 16D detects from the first liquid level sensor 16B. The first valve 16G is opened based on the signal, and the dry air is introduced into the second tank 16A from the air pipe 16E to lower the liquid level. When the liquid level returns to its original state and the detection signal from the first liquid level sensor 16B disappears, the air control device 16D closes the first valve 16G and stops introduction of dry air. On the contrary, when the discharge amount decreases and the liquid level decreases, the second liquid level sensor 15C operates to open the second valve 16H via the air control device 16D, exhausts the gas in the second tank 16A, and liquid level the liquid level. To increase.

As described above, according to the present embodiment, the first pulsation reducing device 15 is provided on the refrigerant suction side of the pump 13, and the first pulsation reducing device 15 leaves a space part to store the first refrigerant. 15A of tanks, the supplementary tank 15B which is connected to the 1st tank 15A in the state arrange | positioned higher than this, and supplements a refrigerant | coolant in the 1st tank 15A, and the 1st tank 15A, and A gas scavenging pipe 15C connecting the space portion of the supplemental tank 15B is provided, and the pulsation of the refrigerant by the pump 13 is reduced by using the gas in the space portion in the first tank 15A as a buffer. At this time, the refrigerant in the first tank 15A vaporizes and decreases, and at the same time, the pressure in the space portion rises to decrease the liquid level, and the space portion in the first tank 15A and the space addition gas scavenging pipe in the supplement tank 15B ( When communicating via 15C), the gas in the first tank 15A via the gas bleed pipe 15C Is taken out into the space in the replenishment tank 15B and the refrigerant in the replenishment tank 15B is replenished into the first tank 15A based on the hydraulic pressure difference, so that the gas in the first tank 15A is degassed. Through 15C, it is held at a constant pressure at all times during the holiday with the replenishment tank 15B, and pulsation can be reliably and reliably reduced at all times.

Moreover, when the space part in the 1st tank 15A and the space part in the replenishment tank 15B communicate, the relief valve 15D which opens the space part to the atmosphere by the pressure of the gas in the replenishment tank 15B was provided. The refrigerant in the replenishment tank 15B can be replenished with the first tank 15A so that the pressure of the gas in the space portion in the first tank 15A can be kept constant, and a stable pulsation-reducing action can be maintained.

Moreover, according to this embodiment, the 2nd pulsation reducing device 16 was provided in the refrigerant | coolant discharge side of the pump 13, The 2nd pulsation reducing device 16 leaves the space part and stores the 2nd tank 16A. And a first liquid level sensor 16B for detecting the upper liquid level upper limit of the refrigerant in the second tank 16A, and a second liquid level sensor 16C for detecting the lower liquid level lower limit of the refrigerant in the second tank 16A. The height of the liquid level in the second tank 16A is controlled within a predetermined range based on the detection signals of the first and second liquid level sensors 16B and 16C. That is, when the pulsation of the refrigerant by the pump 13 is reduced by using the gas in the space portion on the liquid level in the second tank 16A as the buffer, the positive pressure of the pump discharge pressure in the second tank 16A. Even if the liquid level rises due to the dissolution of gas into the refrigerant due to the action of, the liquid level of the refrigerant in the second tank 16A is kept constant based on the detection signals of the first and second liquid level sensors 16B and 16C. By keeping the pressure of the negative gas constant, it is possible to reliably and reliably reduce pulsation at all times.

Moreover, based on the detection signal of the 1st liquid level sensor 16B, the 1st valve 16G which introduces dry air into the 2nd tank 16A is provided, and based on the detection signal of the 2nd liquid level sensor 16C. To provide the second valve 16H for exhausting the gas in the second tank 16A, and based on the detection signals of the first and second liquid level sensors 16B and 16C, the first and second valves 16G. And the air control device 16D for opening and closing control of 16H, the pressure of the gas in the space portion in the second tank 16A can be kept constant.

Moreover, according to this embodiment, the 1st, 2nd pulsation damping devices 15 and 16 were provided in the suction side and the discharge side of the pump 13 of the circulation pipe 12 of the refrigerant | coolant of the test | inspection apparatus 10, respectively. Therefore, the vibration of the mounting table 11 and the circulation pipe 12 can be suppressed or prevented reliably, and the reliability of the inspection of the semiconductor wafer W can be improved.

In addition, in the said embodiment, although the case where the 1st, 2nd pulsation damping devices 15 and 16 were provided in the test | inspection apparatus 10 was demonstrated, this invention is not limited to the said embodiment, The semiconductor wafer W is not limited. It is widely applicable to the semiconductor manufacturing apparatus provided with the mounting base which controls the temperature of to-be-processed objects, such as these, and the liquid circulation circuit which liquids, such as a heat medium, circulate in a base.

This invention can be used suitably for a semiconductor manufacturing apparatus, for example, an inspection apparatus.

While the exemplary embodiments have been disclosed and described using the invention above, numerous modifications and additions to the disclosed arrangements will be made by those skilled in the art without departing from the novel and advanced concepts of the invention as disclosed and claimed in the appended claims. Should be interpreted as possible.

According to the present invention, it is possible to provide a pulsation alleviation device and an inspection device that can reliably and reliably alleviate pulsation at all times even if the liquid vaporizes.

Claims (14)

It is used in the apparatus provided with the pump which circulates a liquid in a base, and the tank which stores the liquid circulating through this pump, and uses the gas in the space part on the liquid level in the said tank as a buffer, In the device for reducing the pulsation of the liquid by The tank for storing the liquid is connected to the tank so that the liquid level of the tank is higher than the liquid level in the tank, and the tank and the space part of the tank are connected through a gas bleed pipe. When the liquid in the tank decreases so that the space in the tank and the space in the make-up tank communicate with each other through the gas bleed pipe, the gas in the tank is drawn out through the gas bleed pipe to the space in the make-up tank. A pulsation alleviation device comprising: replenishing the liquid in the replenishment tank into the tank. The method of claim 1, A pulsation alleviation device, characterized in that the tank and the replenishment tank are provided on the suction side of the pump, respectively. The method of claim 1, The pulsation reducing device further includes a relief valve which opens the space part to the atmosphere at the pressure of the gas in the replenishment tank. A pulsation of the liquid caused by the pump, which is used in an apparatus having a pump for circulating a liquid in a base and a tank for storing a liquid circulating through the pump, using a gas in a space portion on the liquid level in the tank as a buffer. In the device for reducing A first liquid level sensor for detecting an upper liquid level upper limit of the liquid in the tank and a second liquid level sensor for detecting a lower liquid level lower limit of the liquid in the tank; The pulsation alleviation apparatus characterized by controlling the height of the liquid level in the said tank to a predetermined range by keeping the gas pressure of the said space part constant based on the detection signal of the said 1st, 2nd liquid level sensor. The method of claim 4, wherein The pulsation reducing device further comprises a first valve for introducing gas into the tank based on the detection signal of the first liquid level sensor and a second valve for exhausting gas in the tank based on the detection signal of the second liquid level sensor. A pulsation alleviation device comprising: The method of claim 5, wherein The pulsation reducing device further includes a control device for opening and closing the first and second valves based on detection signals of the first and second liquid level sensors. The method of claim 1, The liquid is a pulsation reducing device, characterized in that the vapor pressure is higher than the pressure difference due to the difference in the liquid level between the tank and the refill tank. delete In the inspection apparatus for mounting the object to be processed, the pump for circulating the liquid in the mounting table, the tank for storing the liquid circulated through the pump, the inspection device for inspecting the object on the mounting table , At least one of the pulsation alleviation apparatus of Claim 1, and the pulsation alleviation apparatus of Claim 4 is included, The test | inspection apparatus characterized by the above-mentioned. The method of claim 9, The pulsation reducing device is the pulsation reducing device according to claim 1, wherein the liquid is a heat medium whose vapor pressure is higher than the pressure difference due to the difference in the liquid level between the tank and the supplement tank in the pulsation reducing device. The method of claim 9, A pulsation reducing device for reducing pulsation of the liquid caused by the pump on at least the suction side of the pump. delete delete delete

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