Vacuum processing equipment

Abstract

In a vacuum processing apparatus where the object to be processed is placed inside a vacuum chamber, the responsiveness of temperature control is improved. [Solution] The vacuum processing apparatus 1 comprises a first vacuum chamber 10 having an opening 11 formed at the bottom, a mounting plate 20 which is a plate-shaped member that closes the opening of the first vacuum chamber from below and on which the object to be processed is placed, a temperature control unit 30 provided along the lower surface of the mounting plate for temperature control of the object to be processed placed on the upper surface of the mounting plate, and a second vacuum chamber 40 which surrounds the lower side of the first vacuum chamber together with the lower surface of the mounting plate and the temperature control unit. The structure including the mounting plate and the temperature control unit is such that the force pulling into the first vacuum chamber is suppressed to a force corresponding to the differential pressure between the first vacuum chamber and the second vacuum chamber, the structure can be made thinner and the heat capacity reduced, and the vacuum processing apparatus can improve the responsiveness when temperature control is performed.

Description

Technical Field

[0001] The present disclosure relates to a vacuum processing apparatus in which an object to be processed is placed in a vacuum chamber.

Background Art

[0002] Conventionally, there has been known a vacuum processing apparatus provided with a mounting table so as to close an opening formed in a vacuum chamber, and performing processing on an object to be processed placed on a mounting plate on this mounting table. As this type of vacuum processing apparatus, it is common to provide a temperature control unit on the lower surface side of the mounting plate in order to be able to control the temperature of the object to be processed during processing (see Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above configuration, due to the structure of closing the opening of the vacuum chamber with a structure (mounting table) including the mounting plate and the temperature control unit, this structure is drawn into the evacuated vacuum chamber. Therefore, it is necessary to ensure the strength by making the structure thick enough to withstand the force thus directed into the vacuum chamber. However, in the above configuration, there is a problem that the responsiveness during temperature control is not necessarily high because the heat capacity of the entire structure increases according to the thickness of the structure including the mounting plate and the temperature control unit.

[0005] An object of the present disclosure is to enhance the responsiveness during temperature control in a vacuum processing apparatus.

Means for Solving the Problems

[0006] To solve the above problems, the vacuum processing apparatus in the first phase comprises a first vacuum chamber having an opening formed at the bottom, a plate-shaped member that closes the opening of the first vacuum chamber from below, with a mounting plate on which an object to be processed is placed on its upper surface, a temperature control unit provided along the lower surface of the mounting plate for controlling the temperature of the object to be processed placed on the upper surface of the mounting plate, and a second vacuum chamber that surrounds the lower side of the first vacuum chamber together with the lower surface of the mounting plate and the temperature control unit.

[0007] In this configuration of the vacuum processing apparatus, the upper side of the mounting plate is positioned within the first vacuum chamber, while the lower side of the mounting plate, along with the temperature control unit, is positioned within the second vacuum chamber. As a result, the force pulling the structure, including the mounting plate and temperature control unit, into the first vacuum chamber is reduced to a force corresponding to the pressure difference between the first and second vacuum chambers.

[0008] Therefore, the structure including the mounting plate and temperature control unit does not require the same strength as when the structure is on the atmospheric side, resulting in a thinner structure with reduced heat capacity. In this way, the responsiveness of the vacuum processing apparatus can be improved during temperature control.

[0009] Furthermore, the above phase may be as shown in the second phase below. The second phase includes a first exhaust pump for exhausting the first vacuum chamber, a first detection unit for detecting the air pressure in the first vacuum chamber, a second exhaust pump for exhausting the second vacuum chamber, a second detection unit for detecting the air pressure in the second vacuum chamber, and exhaust control means for controlling the operation of the first exhaust pump and the second exhaust pump, respectively, based on the air pressures detected by the first detection unit and the second detection unit, so that the differential pressure between the first vacuum chamber and the second vacuum chamber is less than a predetermined threshold.

[0010] In this type of vacuum processing apparatus, the differential pressure between the first vacuum chamber and the second vacuum chamber can be kept below a threshold by controlling each exhaust pump.

[0011] Furthermore, the above-described phase may be as shown in the third phase below. The third phase includes an exhaust pump for exhausting the first vacuum chamber and the second vacuum chamber, a valve body for opening and closing either a first exhaust path connecting the first vacuum chamber and the exhaust pump, or a second exhaust path connecting the second vacuum chamber and the exhaust pump, exhaust control means for controlling the operation of the exhaust pump, a first detection unit for detecting the air pressure in the first vacuum chamber, a second detection unit for detecting the air pressure in the second vacuum chamber, and an opening / closing control means for controlling the opening degree of the valve body so that the differential pressure between the first vacuum chamber and the second vacuum chamber is less than a predetermined threshold, based on the air pressure detected by the first detection unit and the second detection unit, respectively.

[0012] In this type of vacuum processing apparatus, the differential pressure between the first vacuum chamber and the second vacuum chamber can be kept below a threshold by controlling the opening of the exhaust pump and valve body.

[0013] Furthermore, the above-mentioned phase may be as shown in the fourth phase below. In the fourth phase, the temperature control unit includes a Peltier module provided along the lower surface of the plate described above.

[0014] In this type of vacuum processing apparatus, a Peltier module, acting as a temperature control unit, can control the temperature of the object to be processed placed on the mounting plate. [Brief explanation of the drawing]

[0015] [Figure 1] A conceptual diagram (front cross-sectional view and block diagram) showing a vacuum apparatus that is the first embodiment of this disclosure. [Figure 2] A conceptual diagram (front cross-sectional view and block diagram) showing a vacuum apparatus that is a second embodiment of the present disclosure. [Figure 3] Flowchart illustrating the exhaust treatment procedure in the embodiments of this disclosure. [Figure 4] A conceptual diagram (front cross-sectional view and block diagram) showing a vacuum apparatus, which is another embodiment of the present disclosure. [Modes for carrying out the invention]

[0016] (1) First Embodiment (1-1) Overall Configuration

[0017] As shown in FIG. 1, the vacuum processing apparatus 1 includes a first vacuum chamber 10 having an opening 11 formed at the lower side, a plate-like mounting plate 20 that closes the opening 11 of the first vacuum chamber 10 from below, a temperature control unit 30 provided along the lower surface of the mounting plate 20, a second vacuum chamber 40 that surrounds the lower side of the first vacuum chamber 10 together with the lower surface of the mounting plate 20 and the temperature control unit 30, a first exhaust pump 51 that exhausts the first vacuum chamber 10, a first detection unit 61 that detects the air pressure in the first vacuum chamber 10, a second exhaust pump 53 that exhausts the second vacuum chamber 40, a second detection unit 63 that detects the air pressure in the second vacuum chamber 40, and a control unit 80 that controls the operation of the entire vacuum processing apparatus 1.

[0018] In addition to the above, in this embodiment, an example is given of a plasma etching apparatus including a plate-like electrode body 110 disposed above the mounting plate 20 in the first vacuum chamber 10 and a power source 120 that supplies a high-frequency voltage between the mounting plate 20 and the electrode body 110.

[0019] The mounting plate 20 is a plate-like member that closes the opening 11 of the first vacuum chamber 10 from below, and the object to be processed 100 is placed on its upper surface. The mounting plate 20 of this embodiment is disposed below the electrode body 110 in the first vacuum chamber 10 and functions as a pair of plasma electrodes together with the electrode body 110.

[0020] The temperature control unit 30 is provided along the lower surface of the mounting plate 20 and indirectly controls the temperature of the object to be processed 100 placed on the upper surface of the mounting plate 20. The temperature control unit 30 of this embodiment includes a plurality of Peltier modules 31 arranged at intervals along the lower surface of the mounting plate 20 and heat exchangers 33 arranged along the lower surfaces of the Peltier modules 31. These Peltier modules 31 indirectly control the temperature of the object to be processed 100 through the mounting plate 20 because their upper surfaces are respectively in contact with the lower surface of the mounting plate 20.

[0021] Among the above, the heat exchanger 33 has a flow path arranged inside thereof for circulating a temperature control medium (refrigerant in this embodiment), and performs heat exchange with the lower surfaces of the Peltier modules 31. The temperature control medium is supplied from a circulator 35 arranged outside the second vacuum chamber 40 to the heat exchanger 33 via a supply path 37, and is returned to the circulator 35 via a recovery path 39.

[0022] The second vacuum chamber 40 has an opening 41 with a larger diameter formed above the opening 11 of the first vacuum chamber 10, and this opening 41 is blocked by the peripheral edge 13 of the opening 11 in the first vacuum chamber 10. Thus, in the second vacuum chamber 40, the mounting plate 20 and the temperature control unit 30 are arranged in the internal space blocked by the peripheral edge 13 of the opening 11 in the first vacuum chamber 10. Note that the structure including the mounting plate 20 and the temperature control unit 30 is fixed inside the second vacuum chamber 40 so as to be positioned below the first vacuum chamber 10.

[0023] The first exhaust pump 51 is connected to the first vacuum chamber 10 by a first exhaust path 55.

[0024] The second exhaust pump 53 is connected to the second vacuum chamber 40 by a second exhaust path 57.

[0025] (1-2) Exhaust treatment The control unit 80 executes an exhaust process for evacuating the first vacuum chamber 10 and the second vacuum chamber 40 to a vacuum according to a program stored in a built-in memory. This exhaust process is started when a start operation for starting the exhaust process is performed on a user interface (not shown).

[0026] In this exhaust process, the operations of the first exhaust pump 51 and the second exhaust pump 53 are controlled so that the pressure difference (differential pressure) in each of the first vacuum chamber 10 and the second vacuum chamber 40 becomes less than a predetermined threshold value. The control unit 80 that performs such control is the exhaust control means in the present disclosure.

[0027] Specifically, after starting the operation of each exhaust pump, the difference in atmospheric pressure (differential pressure) between the first vacuum chamber 10 and the second vacuum chamber 40 is determined based on the outputs of the first detection unit 61 and the second detection unit 63, and the operation of the first exhaust pump 51 and the second exhaust pump 53 is controlled so that this differential pressure falls below a threshold.

[0028] In this embodiment, the principle is to operate each exhaust pump so that the atmospheric pressure in the first vacuum chamber 10 is lower than the atmospheric pressure in the second vacuum chamber 40, and the operating state (such as the strength of the exhaust) is adjusted according to the differential pressure described above.

[0029] This exhaust treatment process will be repeated until the termination operation to end the exhaust treatment is performed.

[0030] (2) Second Embodiment (2-1) Overall structure

[0031] As shown in Figure 2, the vacuum processing apparatus 1 of this embodiment differs from the first embodiment in that it is equipped with only a single exhaust pump 50 and further includes a valve body 70 that opens and closes either the first exhaust path 55 or the second exhaust path 57 (the second exhaust path 57 in this embodiment).

[0032] The valve body 70 is a solenoid valve that opens and closes the exhaust path in response to a command from the control unit 80.

[0033] (2-2) Exhaust treatment The control unit 80 performs an evacuation process to evacuate the first vacuum chamber 10 and the second vacuum chamber 40 to create a vacuum, according to a program stored in its internal memory. This evacuation process is initiated when a startup operation to activate the evacuation process is performed via a user interface (not shown).

[0034] In this exhaust process, as shown in Figure 3, the operation of the exhaust pump and valve body 70 is controlled so that the pressure difference (differential pressure) in the first vacuum chamber 10 and the second vacuum chamber 40 is less than a predetermined threshold.

[0035] Specifically, first, after the exhaust pump 50 starts operating (S110), the valve body 70 opens to its initial state (S120). In S120, the operation of the valve body 70 is controlled so that it opens to the initial state predetermined.

[0036] In this embodiment, the initial state is set such that the opening of the first exhaust path 55 connected to the first vacuum chamber 10 is wider by a predetermined percentage than the opening of the second exhaust path 57 connected to the second vacuum chamber 40 at the position of the valve body 70. As a result, in this embodiment, each vacuum chamber is exhausted such that the air pressure in the first vacuum chamber 10 is lower than the air pressure in the second vacuum chamber 40 by a predetermined value.

[0037] Next, based on the outputs of the first detection unit 61 and the second detection unit 63, the difference in atmospheric pressure (differential pressure) between the first vacuum chamber 10 and the second vacuum chamber 40 is determined (S130).

[0038] Next, the operation of the valve body 70 is controlled so that the differential pressure identified in S130 falls below a threshold (S140). Here, if the differential pressure exceeds a predetermined threshold, the opening degree of the valve body 70 is changed so that the exhaust path leading to the vacuum chamber with lower pressure is narrower by a predetermined unit area at the position of the valve body 70 than the exhaust path leading to the vacuum chamber with higher pressure.

[0039] After S140, there is a waiting period until a predetermined waiting time has elapsed (S150: NO). After the waiting time has elapsed (S150: YES), the process returns to S130, and the subsequent processes are repeated until the termination operation to finish the exhaust process is performed.

[0040] In the exhaust treatment described above, S110 is the exhaust control means in this disclosure, and S120 and S140 are the opening and closing control means in this disclosure.

[0041] (2) Variant Although embodiments of the present invention have been described above, it goes without saying that the present invention is not limited in any way to the above embodiments and can take various forms as long as they fall within the technical scope of the present invention.

[0042] For example, in the above embodiment, the vacuum processing apparatus 1 is exemplified as a plasma etching apparatus equipped with a pair of plasma electrodes in the first vacuum chamber 10. However, it goes without saying that the vacuum processing apparatus can also be applied to apparatuses other than plasma etching apparatuses.

[0043] Furthermore, in the second embodiment described above, a configuration in which the valve body 70 is provided only in the second exhaust passage 57 was illustrated. However, the valve body 70 may be provided only in the first exhaust passage 55. Alternatively, as shown in Figure 4, it may be composed of a first valve body 71 provided in the first exhaust passage 55 and a second valve body 73 provided in the second exhaust passage 57.

[0044] Furthermore, in the above embodiment, an example was shown in which the temperature control unit 30 is configured to indirectly control the temperature of the object to be processed 100 using a Peltier module 31. However, the temperature control unit 30 may also be configured to indirectly control the temperature of the object to be processed 100 using a heat exchanger 33.

[0045] (3) Action, effect In the vacuum processing apparatus 1 of the above embodiment, the upper side of the mounting plate 20 is placed inside the first vacuum chamber 10, while the lower side of the mounting plate 20 is placed inside the second vacuum chamber 40 together with the temperature control unit 30. As a result, the force pulling the structure including the mounting plate 20 and the temperature control unit 30 into the first vacuum chamber 10 is reduced to a force corresponding to the differential pressure between the first vacuum chamber 10 and the second vacuum chamber 40.

[0046] Therefore, the structure including the mounting plate 20 and the temperature control unit 30 does not require the same strength as when the structure is on the atmospheric side, and as a result, the structure can be made thinner and its heat capacity can be reduced. In this way, the responsiveness of the vacuum processing apparatus 1 during temperature control can be improved.

[0047] Furthermore, in the vacuum processing apparatus 1 of the first embodiment, the differential pressure between the first vacuum chamber 10 and the second vacuum chamber 40 can be kept below a threshold by controlling each exhaust pump.

[0048] Furthermore, in the vacuum processing apparatus 1 of the second embodiment, the differential pressure between the first vacuum chamber 10 and the second vacuum chamber 40 can be kept below a threshold by controlling the opening degree of the exhaust pump 50 and the valve body 70.

[0049] Furthermore, in the above embodiment, since the temperature control unit 30 is located inside the second vacuum chamber 40, it is separated from the internal space of the first vacuum chamber 10 and is not exposed to the environment during processing of the object to be processed 100. This makes it possible to suppress the influence that the operation of the temperature control unit 30 and the processing of the object to be processed 100 have on the other. [Explanation of Symbols]

[0050] 1... Vacuum processing device, 10... First vacuum chamber, 11... Opening, 13... Periphery, 20... Mounting plate, 30... Temperature control unit, 31... Peltier module, 33... Heat exchanger, 35... Circulator, 37... Supply path, 39... Recovery path, 40... Second vacuum chamber, 41... Opening, 50... Exhaust pump, 70... Valve body, 71... First valve body, 73... Second valve body, 80... Control unit, 100... Object to be processed, 110... Electrode body, 120... Power supply.

Claims

1. A first vacuum chamber with an opening formed at the bottom, A plate-shaped member that closes the opening of the first vacuum chamber from below, and a mounting plate on which the object to be processed is placed on its upper surface, A temperature control unit is provided along the lower surface of the aforementioned mounting plate for controlling the temperature of the object to be processed which is placed on the upper surface of the aforementioned mounting plate, The system comprises a second vacuum chamber that surrounds the lower side of the first vacuum chamber together with the lower surface of the aforementioned mounting plate and the temperature control unit, Vacuum processing equipment.

2. A first exhaust pump for exhausting the first vacuum chamber, A first detection unit for detecting the air pressure in the first vacuum chamber, A second exhaust pump for exhausting the second vacuum chamber, A second detection unit for detecting the air pressure in the second vacuum chamber, The system includes exhaust control means that controls the operation of the first exhaust pump and the second exhaust pump, respectively, based on the atmospheric pressure detected by the first detection unit and the second detection unit, so that the differential pressure between the first vacuum chamber and the second vacuum chamber is less than a predetermined threshold. The vacuum apparatus according to claim 1.

3. An exhaust pump for evacuating the first vacuum chamber and the second vacuum chamber, A valve body that opens and closes either the first exhaust path connecting the first vacuum chamber and the exhaust pump, or the second exhaust path connecting the second vacuum chamber and the exhaust pump, Exhaust control means for controlling the operation of the exhaust pump, A first detection unit for detecting the air pressure in the first vacuum chamber, A second detection unit for detecting the air pressure in the second vacuum chamber, The system includes an opening / closing control means that controls the opening degree of the valve body so that the differential pressure between the first vacuum chamber and the second vacuum chamber is less than a predetermined threshold, based on the atmospheric pressure detected by the first detection unit and the second detection unit, respectively. The vacuum apparatus according to claim 1.

4. The temperature control unit includes a Peltier module provided along the lower surface of the plate described above. The vacuum apparatus according to any one of claims 1 to 3.

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