JP3503602B2 - Plasma cleaning equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma cleaning device for performing plasma cleaning on an object in a closed space.

[0002]

2. Description of the Related Art For example, a plasma cleaning apparatus for subjecting an object such as a substrate to a surface treatment by plasma cleaning in a closed space is used in a manufacturing line of electronic parts and an assembly line of electronic equipment.

Next, a conventional plasma cleaning device will be described with reference to FIG. FIG. 16 is a perspective view of a conventional plasma cleaning device. In FIG.
Reference numeral 1 denotes a main body that forms a closed space, and the plasma cleaning is performed in the closed space as described above. Reference numeral 2 denotes an inlet / outlet provided on the front surface of the main body 1, and 3 denotes a gate for opening / closing the inlet / outlet 2. In addition, since the gate 2 opens and closes the doorway 2,
The upper end of the rod 5 of the cylinder 4 fixed to the main body 1 is connected to the gate 3.

That is, when the rod 5 is projected by driving the cylinder 4, as shown in FIG.
Can be closed to form a closed space in the main body 1,
When the rod 5 is immersed, the entrance / exit 2 can be exposed to the outside. In addition, when the entrance 2 is blocked by the gate 3,
The main body 1 is closed to the outside except for the doorway 2 so that a closed space is formed in the main body 1.

Reference numeral 6 denotes an object sent along the carrying line indicated by the arrow L. When the object 6 is subjected to plasma cleaning, the object 6 is once placed on the supply unit T arranged in the carrying line L. Placed. Reference numeral 7 is a loading / unloading means for putting the object 6 placed on the supply unit T before plasma cleaning into the main body 1 or for returning the plasma-cleaned target object 6 in the main body 1 to the supply unit T, that is, the transfer line L. Is.

Next, the operation of the conventional plasma cleaning device will be described. First, in order to make the inside of the main body 1 an atmosphere for plasma cleaning, the entrance / exit 2 is closed by the gate 3. Next, the target object 6 is sent in the direction of the transport line L and placed on the supply unit T.

Next, the loading / unloading means 7 is driven to remove the object 6 from the supply section T. Then, the gate 3 is lowered to open the entrance / exit 2, and the object 6 is put into the main body 1 by the entrance / exit means 7. Next, the access means 7 is retracted from the main body 1, the gate 3 is raised, and the entrance 2 is closed. As a result, the inside of the main body 1 becomes a closed space, and the object 6 is present in the closed space.

Next, plasma cleaning of the object 6 is performed in the main body 1. Then, when the plasma cleaning is completed, the gate 3 is lowered to open the entrance / exit 2.
Then, the retracting means 7 which has been retracted is driven into the main body 1, and the plasma-cleaned target 6 existing in the main body 1 is taken out from the main body 1. Next, the gate 3 is raised to close the entrance 2 and the entrance / exit means 7 returns the plasma-cleaned object 6 to the supply part T. After that, the target object 6 that has undergone plasma cleaning is sent out by the transfer line L.

[0009]

However, the conventional plasma cleaning device has the following problems. In the conventional plasma cleaning device, the periphery of the electrode to which a high frequency voltage is applied to generate plasma is
Since it was completely surrounded by the wall surface and it was difficult to dissipate the heat of this electrode to the outside, this electrode was cooled by a water cooling method.

[0010] In this case, a pipe and a pump for circulating the water to be actuated, a heat exchanger, and the like are indispensable, and there is a problem that the entire device becomes large-scale.

Therefore, an object of the present invention is to provide a plasma cleaning device which can be formed compactly.

[0012]

A plasma cleaning apparatus according to a first aspect of the present invention emits plasma by decompressing a closed space.
A plasma cleaning device for performing plasma cleaning of an object in this closed space by using a horizontal base and a state in which the base is insulated from the base and the lower part is external.
An electrode that is open and attached to the electrode, a high-frequency power source that applies a high-frequency voltage to the electrode, a lid that is open at the bottom and that forms a closed space when in contact with the base, and the lid that covers the base. A contacting / separating means for contacting / separating with each other, a conveying means for carrying out an operation of conveying an object when the lid is separated from the base by the contacting / separating means, and a cooling means for cooling the electrode from below by an air cooling method. It was

A plasma cleaning apparatus according to a second aspect of the present invention is the plasma cleaning apparatus according to the first aspect, wherein the cooling means is a cooling fin thermally coupled to a lower portion of the electrode, and air is blown to the cooling fin. Have a fan to do.

In the above structure, a high frequency voltage is applied to the electrode during plasma cleaning, and the temperature of the electrode rises. Here, in this means, the lower side of the electrode is opened to the outside, and the electrode is cooled from the lower side by an air cooling method. Therefore, it is possible to omit large components such as piping, a pressure pump, and a heat exchanger, which are indispensable in the conventional plasma cleaning apparatus, and it is possible to make the entire scale compact.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall perspective view of a plasma cleaning device according to an embodiment of the present invention, FIGS. 2 and 3 are perspective views of a contacting / separating means according to an embodiment of the present invention, and FIGS. 6 is a perspective view of a bracket according to an embodiment of the present invention, FIG. 6 is an exploded perspective view of a lid according to an embodiment of the present invention seen from below, and FIG. 7 is a perspective view of a lid according to one embodiment of the present invention seen from below. FIG. 8 is an exploded perspective view of a base according to one embodiment of the present invention, FIG. 9 is a plan view of the base according to one embodiment of the present invention, and FIGS. 10 and 11 are plasmas according to one embodiment of the present invention. FIG. 12 is a cross-sectional view of the cleaning device, FIG. 12 is a perspective view of an auxiliary structure of an electrode in one embodiment of the present invention, FIG. 13 is an end view taken along line XX of FIG. 2, and FIG. FIG. 15 is a plan view showing the present invention. A conveying operation explanatory diagram in the embodiment. The plasma cleaning apparatus of the present embodiment has a large number of constituent elements, and there are many points in which detailed portions cannot be illustrated. Therefore, first, an outline will be described with reference to FIG. 1, and then a detailed description will be sequentially given. I will do it.

In FIG. 1, reference numeral 8 is a base whose upper surface is formed to be substantially horizontal. An upright portion 8a that is taller than the upper surface of the base 8 is provided on the back side of the base 8, and a monitor 8b is disposed on the front surface of the upright portion 8a. An operator uses the monitor 8b to monitor the plasma cleaning device. You can grasp the operation status of.

On the upper surface of the base 8, a straight conveying path L is formed from the lower left to the upper right in FIG. Reference numeral 9 denotes a supply magazine which is arranged on the upstream side of the transport path L and stores the target objects 6 before plasma cleaning in a multi-tiered manner. 10
Is a recovery magazine which is arranged on the downstream side of the transport path L and stores the target object 6 that has been plasma cleaned.

Reference numeral 11 denotes an extruding cylinder for feeding the object 6 before plasma cleaning from the supply magazine 9 to the conveying path L. Reference numeral 12 is the supply magazine 9 side of the upper surface of the base 8 and is inline-deployed on the conveyance path L to convey the conveyance path L.
The base that forms a part of
It is a lid that is supported by the base 12 so as to be able to approach and separate from above.

The configurations of the base 12 and the lid 13 will be described in detail later, but the lid 13 constitutes a part of the transport path L.
A closed space is formed on the transport path L when it comes into contact with. That is, the base 12 plays a role of a member that surrounds the closed space together with the lid 13 and a role of the transport path L. Reference numeral 14 denotes a wire bonding portion which is disposed between the base 12 and the recovery magazine 10 and is offset from the transport path L to a position slightly rearward.

In this embodiment, a substrate is adopted as the object 6, and the object 6 is subjected to plasma cleaning as an example of surface treatment in a closed space formed by the lid 13 and the base 12, The deposits or protrusions existing on the electrodes of the substrate are removed to facilitate the bonding of these electrodes. Then, the adjacent wire bonding sections 14 bond the object 6 immediately after the plasma cleaning, and store the object 6 in the recovery magazine 10.

The leading end of 15 reaches the conveyance path L, and the conveyance path L
And 16 is a second arm that is parallel to the first arm 15 and is located at a position spaced from the first arm 15 to the downstream side of the transport path L by a certain distance. Reference numeral 17 denotes a cover formed on the front side of the upper surface of the base 8 so as to be long in parallel with the transport path L. As will be described later in detail, an arm moving mechanism for moving the first arm 15 and the second arm 16 in parallel with the transport path L while keeping the first arm 15 and the second arm 16 in parallel with each other is housed in the cover 17. .

Reference numeral 18 denotes a pair of guides for guiding the object 6 along the transport path L from the upstream side of the wire bonding section 14 to the recovery magazine 10 in the transport path L. Here, the first arm 15 and the second arm 16
Corresponds to a transporting unit that transports the object 6 along the transport path L. The arm moving mechanism and the operation of transporting the object 6 will be described in detail later.

A mechanism (contacting / separating means) for raising / lowering the lid 13 and for placing the lid 13 in the horizontal / vertical state will be described with reference to FIGS.

Here, the posture of the lid 13 will be defined.
First, when the lower end surface of the lid 13 is in the horizontal plane, the lid 13 is said to be horizontal. On the other hand, when the lower end surface of the lid 13 is in the vertical plane, the lid 13 is said to be in the vertical state.

When the lower end surface of the lid 13 is in close contact with the base 12, the lid 13 is said to be in a lowered state.
The lower end surface of 3 separates from the base 12, and the lid 13 and the base 12
It is said that the lid 13 is in a raised state when there is a gap between the lid 13 and.

When the lid 13 is in the horizontal state and in the lowered state, this is called a horizontal lowered state.
When two states are established at the same time, these states shall be consecutively expressed.

By the way, the lid 13 has the following mechanism.
It is supported so that it can take three states of a horizontal descending state, a horizontal ascending state, and a vertical ascending state. In FIG. 2, the lid 13
Is in a horizontally lowered state, and in FIG. 3, the lid 13 is in a horizontally raised state.

In FIG. 2, reference numeral 20 denotes a frame having a horizontal portion 20a fixed to the upper surface of the base 8 and standing portions 20b and 20c which stand vertically from both ends of the horizontal portion 20a. Further, guides 21 and 22 having an L-shaped cross section and having tips directed outward are provided on the upper portions of the rising portions 20b and 20c of the frame 20, respectively.

Reference numeral 23 is a cylinder as a contacting / separating means fixed to the center of the horizontal portion 20a so that the rod 23a thereof faces upward. The upper end of the rod 23a is connected to the center of the horizontal portion 24a of the U-shaped arm 24 having a U-shape.

The above-mentioned guides 21 and 22 are slidably engaged with the standing portions 24b and 24c, which stand up from both ends of the horizontal portion 24a of the U-shaped arm 24, respectively. A shaft 26 is attached to the upper ends of the standing portions 24b and 24c, and a bracket 25 is pivotally supported by the shaft 26 so as to be rotatable in a vertical plane.

Here, as shown in an enlarged manner in FIG. 4, the bracket 25 has a substantially Z-shape which is bent at two places at a right angle. Of the brackets 25, 25a is the first piece, 25b
Is a second piece having the same length as the first piece 25a and bent 90 degrees with respect to the first piece 25a. The intersection of the center lines of the first piece 25a and the second piece 25b coincides with the axis of the shaft 26.

Further, 25c is formed longer than the second piece 25b, and the first piece 25a and the second piece 2b are different from the second piece 25b.
The third piece is bent 90 degrees in the opposite direction to the relationship with 5b. And, the first piece 25a and the second piece 25b,
A first pin hole 27 and a second pin hole 28 are opened in the thickness direction at positions equidistant from the axis of the shaft 26.

Further, as shown in FIG. 4, when the third piece 25c faces the horizontal direction, the standing portions 24b, 2 of the U-shaped arm 24 are formed.
4c, the second pin hole 28 opened in the second piece 25b
An insertion hole 24d is formed at a position corresponding to. Therefore, as shown in FIG. 4, the third piece 2 of the bracket 25 is
When 5c faces the horizontal direction, the second pin hole 28 and the insertion hole 24
By matching d and inserting the pin 30 into these, rotation of the bracket 25 can be prohibited at the position where the third piece 25c faces the horizontal direction.

Further, since the shaft 29 for supporting the side surface 13a of the lid 13 so as to be swingable in the direction of the arrow N2 is attached to the tip of the third piece 25c of the bracket 25, the bracket 25 as described above. If the rotation of the lid 13 is prohibited, the lid 13 can be held in a horizontal state.

On the other hand, as shown in FIG. 5, when the third piece 25c is oriented in the vertical direction, the first pin hole 27 formed in the first piece 25a coincides with the insertion hole 24d.

At this time, the first pin hole 27 and the insertion hole 24d
The third piece 25c can be left standing upright by inserting the pin 30 therethrough. Further, as described above, since the side surface 13a of the lid 13 is swingably supported by the shaft 29 with respect to the bracket 25, the lid 13 can be in a vertical state.

Here, when the lid 13 is in the vertical state, the lid 1
The inside of 3 is exposed to the outside. Therefore, the member mounted inside the lid 13 can be easily replaced or cleaned. Further, since the lid 13 is erected, the space above the base 12 is widened, so that similar maintenance can be performed on the base 12 and the members attached to the base 12.

As described above, in the plasma cleaning apparatus according to the present embodiment, the lid 13 is vertically erected to expose the inside to the outside, so that the space between the lid 13 and the base 12 (this space is the transport path L). (It is also a part of) is widely opened, and it is extremely easy to perform maintenance.

Next, with reference to FIGS. 2 and 3, the operation of shifting the lid 13 from the horizontally lowered state to the horizontally raised state will be described. Now, as shown in FIG. 2, when the lid 13 is in the horizontal descending state, the rod 23a is retracted and the pin 30 is moved to the second position.
The lid 13 is inserted into the pin hole 28 and the insertion hole 24d, and the lid 13 is held in a horizontal state. And the lower end surface of the lid 13 is
It is in close contact with the base 12.

As will be described later, when the lid 13 is in the horizontal descending state and the lid 13 and the base 12 form a closed space, and the plasma cleaning is performed in the closed space, the closed space is higher than the atmospheric pressure. Since the pressure is kept low, the lid 13 does not have to be sufficiently pressed against the base 12 by the operating force of the cylinder 23.
Stick to.

Next, in order to bring the lid 13 into a horizontally raised state,
The cylinder 23 is driven to cause the rod 23a to project. Then, the U-shaped arm 24 is vertically guided while being guided by the guides 21 and 22, and accordingly, the bracket 25 is lifted while maintaining the state in which the third piece 25c faces the horizontal direction. As a result, the lid 13 rises apart from the base 12 in the horizontal state. Thereby, as shown in FIG.
A gap is formed between the base 3 and the base 3 so that the first arm 15 and the second arm 16 for pushing the object 6 can pass through the gap (arrow N1).

Next, the structure of the lid 13 will be described in detail with reference to FIGS. 6 and 7. FIG. 6 is an exploded perspective view of the lid as viewed from below. As shown in FIG. 6, the lid 13 has a shape in which the lower side is opened. Of these, 13b is a lid body having a substantially rectangular shape. The lid main body 13b is capable of completely containing the target object 6 inside, a processing chamber 13c for performing plasma cleaning as the plasma cleaning on the target object 6, and a processing chamber 13c smaller than the processing chamber 13c and continuous to the side of the processing chamber 13c. The exhaust chamber 13d is provided.

Further, 13e is a window for observing the inside of the processing chamber 13c from the outside, and 13f is a screw hole provided at four places in the processing chamber 13c. Further, the processing chamber 13c and the exhaust chamber 13
An inner cover 31 is attached to the wall surrounding d.
The surface S of the inner cover 31 that faces the inside of the processing chamber 13c and the exhaust chamber 13d is formed with many fine irregularities so that the surface area of the surface S is increased.

This is because when the object 6 is plasma-cleaned in the processing chamber 13c, the scraped-off minute substance scatters. By making the minute substance easily adhere to the surface S, the object 6 can be easily removed. This is for preventing the fine substance scraped off from reattaching to the object 6.

Reference numeral 32 is a first electrode for generating plasma, and the first electrode 32 has a screw hole 3 as shown in FIG.
The 2a and the screw hole 13f are fixed to the processing chamber 13c by being screwed with the set screw 33. The first electrode 3
2 is electrically grounded.

Next, referring to FIGS. 8 and 9, the base 1
2 and its related members will be described. FIG. 8 is an exploded perspective view of the base. As shown in FIG. 8, the base 12 is composed of a thick plate slightly larger than the lid 13 shown in FIG. A rectangular opening 12a is formed in the center of the base 12 for inserting the second electrode 34 to which a high frequency voltage is applied by the cable 35.

The portion of the base 12 that faces the processing chamber 13c of the lid 13 is a processing area A for performing plasma cleaning on the object 6, and faces the exhaust chamber 13d adjacent thereto. The part is an exhaust area B.

Here, a groove 12e is formed in a portion of the base 12 that abuts the lower end surface of the lid 13, and the groove 12e is formed.
An O-ring 39 as a contact portion is fitted in the central portion of the. The upper end of the O-ring 39 is located slightly below the upper surface of the base 12 as shown in FIG.

As shown by the arrow N2 in FIG. 9, when the object 6 crosses the base 12, the object 6 and the first arm 15 and the second arm 16 do not touch the O-ring 39,
This is to make it possible to move smoothly. Further, when the object 6 crosses over the base 12 in this way, the object 6, the first arm 15, and the second arm 16 are moved by the O-ring 3
By avoiding contact with 9, it is possible to avoid damage to the O-ring 39, maintain high airtightness in the sealed space 60, and prevent the degree of vacuum from decreasing.

In FIG. 8, 12b is a gas opened at a corner of the processing area A for supplying an argon gas as an operating gas supplied from a gas cylinder described later into the processing area A (that is, the processing chamber 13c). It is a supply port.

Further, in the processing area A of the base 12, a plurality of screw holes 12c are formed in a direction orthogonal to the transport path L. Then, of these screw holes 12c, one that fits the width of the object 6 is selected, and the selected screw hole 12c is selected.
In addition, guides 40 and 41 that form a part of the transport path L and guide the object 6 are fixed by set screws 42. Of course object 6
When the width of the screw hole 12c is changed, the position of the selected screw hole 12c can be changed. The guides 40 and 41 are made of an insulating material.

On the other hand, in the center of the exhaust area B of the base 12, after the plasma cleaning is completed, argon gas or the like is exhausted to the outside, or the processing chamber 13c and the exhaust chamber 1 are exhausted.
Inlet 1 for discharging the atmosphere in 3d to the outside
2d has been opened. Further, the suction port 12d is covered with an electrically grounded wire net 38, and when particles charged during plasma generation pass through the suction port 12d, the wire net 38 removes electricity. .

On the other hand, the lower part of the second electrode 34 is open to the outside, and the second electrode 3 is located below the second electrode 34.
The cooling fins 36 are thermally coupled to radiate the heat generated during the operation of 4 to the outside. This way,
The lower side of the second electrode 34 is opened to the outside, and cooling by an air cooling method using the cooling fins 36 and the like becomes possible, so that compact and efficient cooling can be performed.

Now, the second electrode 34 is provided with a flange portion 34a at a position descending downward. An insulating plate 37 having the same shape as the flange portion 34a is interposed between the flange portion 34a and the lower surface of the base 12,
The base 12 and the flange portion 34 a are fixed by the bolt 43. Here, the insulating plate 37 allows the base 1
2 and the second electrode 34 are prevented from being short-circuited.

FIG. 10 is a sectional view of a plasma cleaning apparatus according to one embodiment of the present invention. In FIG. 10, the lid 13 is in a horizontally raised state, and the lid 13 and the base 12 are
There is a gap between the two and the object 6 is pushed by the first arm 15. Next, the moving mechanism of the first arm 15 and the second arm 16 will be described with reference to FIG.

Inside the cover 17 shown in FIG. 1, a linear guide 44 parallel to the conveyance path L is provided. A slider 45 fixed to a moving frame 46 is slidably engaged with the linear guide 44, and the moving frame 46 can move freely in parallel to the transport path L (direction perpendicular to the paper surface). .

Further, the lower part of the moving frame 46 has a conveyance path L.
It is fixed to the timing belt 49 that is aligned with
The driving force of the motor 47 is transmitted to the timing belt 49 via the pulley 48.

A shaft 50 is provided on the upper part of the moving frame 46.
The base end portion of the first arm 15 whose tip portion is bent downward in a hook shape is pivotally supported on the shaft 50. The rod 52 of the cylinder 51 fixed to the moving frame 46 is connected to the base of the first arm 15.

Therefore, when the motor 47 is driven, the first arm 15 can be reciprocated in parallel with the conveyance path L, and when the cylinder 51 is driven and the rod 52 is projected and retracted, the first arm 15 is drawn by a chain line. It can be removed from the target 6 as shown, or the first arm 15 can be brought into contact with the end of the target 6 as shown by the solid line.

When the first arm 15 is brought into contact with the object 6 and the motor 47 is driven, the object 6 can be pushed along the conveyance path L. The second arm 16 also has a moving mechanism similar to that of the first arm 15.
Here, in the present embodiment, the same timing belt 49 is provided with the first arm 15 and the second arm 16 separated by a certain distance.
However, the first arm 15 and the second arm 16 may be independently moved in parallel with the transport path L by separate moving means.

Next, the cooling means for the second electrode 34 will be described. In FIG. 10, reference numeral 53 is a fan that blows air to the cooling fins 36. In the present embodiment, the air sent from the fan 53 is directed to the opposite side of the wire bonding portion 14. This is the wire bonding part 1
This is to prevent it from affecting 4. Further, since the lower side of the second electrode 34 is opened to the outside and the second electrode 34 is cooled by the air cooling method in this way, like the conventional plasma cleaning device, a pipe for circulating cooling water, a pressure pump, It is not necessary to provide a large-sized component such as a heat exchanger, and the entire plasma processing apparatus can be made compact.

Now, when the lid 13 is horizontally lowered, as shown in FIG. 11, the lower end surface of the lid 13 becomes O inside the groove 12e.
A closed space 60 that is in close contact with the ring 39 and that includes the processing chamber 13c and the exhaust chamber 13d is formed. In the processing chamber 13c, the grounded first electrode 32 and the second electrode 34 to which a high frequency voltage is applied face each other, and the object 6 supported by the guides 40 and 41 is positioned between these electrodes 32 and 34. Will be done. Further, the exhaust chamber 13d communicates with the suction port 12d through the wire net 38.

Next, with reference to FIG. 12, an electrode and its auxiliary structure in the plasma cleaning apparatus of the present embodiment will be described. As already described with reference to FIGS. 6 to 9, in the plasma cleaning apparatus of the present embodiment, the lid 13 is provided with the first electrode 32 which is grounded, and the base 12 facing the first electrode 32 is provided with a high frequency voltage. A second electrode 34 to be applied is provided.

As shown in FIG. 12, a high frequency applying section 61 is connected to the second electrode 34 via a cable 35. The high frequency applying unit 61 includes a high frequency power source 62 that generates a high frequency voltage, and a tuner 63 that adjusts the high frequency voltage generated by the high frequency power source 62 and outputs the high frequency voltage to the cable 35, that is, the second electrode 34.

Therefore, the object 6 is placed between the lid 13 and the base 12.
Position, the lid 13 is horizontally lowered, and the first electrode 3
By arranging the second electrode 34 and the second electrode 34 at a predetermined distance from each other and operating the high-frequency applying section 61, it is possible to create an electrical environment for generating plasma in the closed space 60. Then, when the high-frequency applying unit 61 is operated, the second electrode 34 generates heat. Therefore, the fan 53 that cools the cooling fin 36 thermally coupled to the second electrode 34 is also operated, and the second electrode 34 is excessively operated. Don't let the temperature rise.

Next, referring to FIGS. 12 and 13, a gas supply section 64 for supplying argon gas into the closed space 60 through a gas supply port 12b opened in the base 12, and an exhaust area B of the base 12. The pressure adjusting unit 68 that measures and controls the pressure in the closed space 60 via the suction port 12d opened in the following will be described.

First, in the gas supply unit 64, 65 is a gas cylinder for storing argon gas as an operating gas, 66 is a gas control unit for controlling the flow rate and pressure of the discharged argon gas, 67 is the gas control unit 66 and the gas. It is a discharge pipe that connects to the supply port 12b. Therefore, when the gas supply unit 64 is operated, the argon gas whose flow rate and the like are controlled can be sent into the processing chamber 13c through the gas supply port 12b. The gas supply port 12b is located at a position apart from the suction port 12d in the processing area A, and the suction port 1
Since 2d is provided in the exhaust area B, which is separated from the processing area A, the argon gas cannot reach the suction port 12d unless the argon gas passes through the processing area A, and the argon gas is sufficiently spread to the processing area A. It is possible to suppress variations in the concentration of the argon gas.

As will be described later, when the argon gas is supplied to the processing area A instead of being discharged as a simple gas to the suction port 12d, the pressure inside the closed space 60 is reduced to a vacuum. The second electrode 34
Since a high frequency voltage is applied to the argon gas, the argon gas becomes plasma, and the object 6 is etched (plasma cleaning). Although argon gas is used to generate plasma in this embodiment, another gas may be used.

Next, the pressure adjusting section 68 will be described. The pressure adjusting unit 68 includes the following four systems. The first system is a vacuum system. That is, the discharge port of the vacuum pump 19 described above is connected to the suction port 12d through the vacuum pipe 69. Reference numeral 70 denotes a vacuum system valve provided in the middle of the vacuum pipe 69. Therefore, when the vacuum pump 19 is operated and the vacuum system valve 70 is opened, the inside of the closed space 60 can be decompressed to a substantially vacuum state.

The second system is an atmosphere open system. That is,
An atmosphere opening pipe 71 is connected to the suction port 12d, and the atmosphere opening pipe 71 reaches an atmosphere opening port 73 via an atmosphere opening valve 72. Therefore, after the closed space 60 is evacuated using the above-mentioned vacuum system, the air release valve 7
When 2 is opened, the atmosphere can be introduced from the atmosphere opening port 73 into the enclosed space 60 through the atmosphere opening pipe 71 to restore the inside pressure of the enclosed space 60 to the atmospheric pressure.

The third system is the system of the pressure switch 74. The pressure switch 74 is for detecting whether or not the inside of the closed space 60 has returned to atmospheric pressure when returning the inside of the closed space 60 to atmospheric pressure using an atmosphere open system. The fourth system is the system of the vacuum gauge 75. The vacuum gauge 75 is for measuring the vacuum pressure in the closed space 60 when the pressure in the closed space 60 is reduced using a vacuum system. The pressure switch 74 may be omitted.

13 which is an end view taken along line XX of FIG.
As shown in FIG.
6, downwardly opening first port 76a, second port 7
6b, the third port 76c, and the fourth port 76d, respectively. Also, these ports 76a-76d
Are all connected inside the connection unit 76 to a common port 76e that opens upward, and the common port 76e is directly connected to the suction port 12d of the base 12.

Next, the lid 13 is in the horizontally raised state, and the lid 1
An operation from when the object 6 is sent between the substrate 3 and the base 12 to when the plasma cleaning for the object 6 is completed will be described. First, when the target object 6 is sent between the lid 13 and the base 12, the target object 6 is supported in the transport path L by guides 40 and 41 that form a part of the transport path L. Since the lid 13 is in the raised state, the surroundings of the object 6 are at atmospheric pressure.

Next, as shown in FIG. 11, the cylinder 2
3 is driven to bring the lower end surface of the lid 13 into contact with the O-ring 39, and the lid 13 and the base 12 form a closed space 60. Next, the vacuum pump 19 is driven to drive the vacuum system valve 70.
Is opened, and the pressure in the closed space 60 is reduced. At this time, the vacuum pressure in the closed space 60 is monitored by the vacuum gauge 75.

When the pressure in the closed space 60 is sufficiently lowered,
The gas supply unit 64 is operated to supply the argon gas into the processing chamber 13c in the closed space 60 through the gas supply port 12b. Then, the high frequency applying section 61 is operated to operate the second electrode 3
A high frequency voltage is applied to 4 to generate plasma in the processing chamber 13c. Then, the target 6 is cleaned by the charged particles in the plasma.

At this time, although the charged particles may be scattered toward the suction port 12d side, since the grounded wire net 38 is attached to the suction port 12d, the charged particles are charged by the wire net 38.
If it adheres to the battery, the charge will be removed and charged particles will not reach the vacuum system. Then, this state is maintained for a predetermined time. This time is for thorough cleaning,
It is a preset time.

When this predetermined time elapses, the high frequency application is stopped and further the supply of argon gas by the gas supply unit 64 is stopped. Further, the vacuum system valve 70 is closed. Then, the atmosphere opening valve 72 is opened, and the atmosphere is introduced from the atmosphere opening port 73 into the closed space 60. Then, the enclosed space 60
Although the pressure in the inside rises, at this time, it is monitored by the pressure switch 74 whether or not the pressure in the closed space 60 returns to the atmospheric pressure.

When the inside of the closed space 60 returns to the atmospheric pressure, the atmosphere opening valve 72 is closed and the cylinder 23 is driven to bring the lid 13 into a horizontally raised state. Then, the object 6 that has been plasma cleaned is retracted from between the lid 13 and the base 12, and the object 6 that has not been plasma cleaned is removed from the lid 13.
Between the base and the base 12.

Next, referring to FIGS. 14 and 15, the object 6 in the plasma cleaning apparatus of the present embodiment will be described.
The carrying operation will be described. FIG. 14 is a plan view showing the transport path according to the embodiment of the present invention. As described above, the object 6 is transported mainly by using the first arm 15 and the second arm 16 as the transporting means. The first arm 15 and the second arm 16 are both fixed to a single timing belt 49 at a constant interval t, and in the direction parallel to the transport path L,
The arm 15 and the second arm 16 move integrally.

On the other hand, the first arm 15 and the second arm 16 are independently provided with a cylinder 51 for vertically moving the arm as shown in FIG.
5 and the second arm 16 can be independently moved up and down.

In the following description, the first object 6X has already been plasma-cleaned and has been wire-bonded by the wire bonding section 14 in order from the downstream side of the transport path L, and the second object 6Y is hermetically sealed. The above-mentioned plasma cleaning is performed in the space 60, and the third
It is assumed that the object 6Z has not been plasma cleaned yet and is stored in the supply magazine 9.

Now, in the positional relationship of FIG. 14, the wire bonding to the first object 6X and the second object 6Y are performed.
When the plasma cleaning is completed, the lid 13 is brought into the horizontal rising state. Then, as shown in FIG.
The second arm 16 is brought into contact with the first object 6X, the first arm 15 is brought into contact with the second object 6Y, and the motor 47 is driven to transfer the first object 6X to the recovery magazine 10 and the second object 6Y. Are pushed to the front of the wire bonding portion 14 (arrow M1). In parallel with this, the extrusion cylinder 11
Is driven to push out the third object 6Z from the supply magazine 9 to approach the gap between the lid 13 and the base 12.

Next, as shown in FIG. 15 (a), the first arm 15 and the second arm 16 are raised to move the first arm 15 to the front of the third object 6Z and the second arm 16 to the first position. Two
The object 6Y is moved in front of each other (arrow M
2). Then, as shown in FIG. 15C, the first arm 15 is brought into contact with the third object 6Z, and the second arm 16 is brought into contact with the second object 6Y, so that the first arm 15 and the second arm 16 cause The third object 6Z is pushed to the position of the second object 6Y in FIG. 14, and the second object 6Y is pushed to the position of the first object 6X in FIG. 14 (arrow M3).

After that, the first arm 15 and the second arm 16
Is returned to the position shown in FIG. 14 and the lid 13 is brought into a horizontally lowered state.
Then, plasma cleaning for the third object 6Z and wire bonding for the second object 6Y are performed in parallel. By repeating the above-described operation, a step of wire-bonding the object immediately after plasma cleaning is performed.

As described above, in the plasma cleaning apparatus of the present embodiment, the plasma cleaning apparatus can be deployed inline on the transfer path L, and the plasma-cleaned object 6 can be removed from the downstream side of the transfer path L of the plasma cleaning apparatus. The object 6 before the plasma cleaning can be moved into the plasma cleaning device from the upstream side of the conveyance path L of the plasma cleaning device almost at the same time. As a result, plasma cleaning and transportation of the object 6 can be performed with almost no loss time, and productivity can be significantly improved.

[0086]

According to the plasma cleaning apparatus of the present invention,
A base, a guide provided on the base for guiding an object, and a lid that is open at the bottom and is supported so that it can come into contact with and separate from the base from above, and that forms a closed space when it comes into contact with the base. And a first electrode provided on the lid and grounded, and a second electrode provided on the base to which a high-frequency voltage is applied. The lower part of the second electrode is opened to the outside, and the second electrode is air-cooled from below. Since the cooling means for cooling is provided, the second electrode can be sufficiently cooled by a small-scale cooling means, and the second electrode can be formed more compactly than the conventional plasma cleaning device which has to adopt the water cooling method.

[Brief description of drawings]

FIG. 1 is an overall perspective view of a plasma cleaning device according to an embodiment of the present invention.

FIG. 2 is a perspective view of a contacting / separating unit according to an embodiment of the present invention.

FIG. 3 is a perspective view of a contacting / separating unit according to an embodiment of the present invention.

FIG. 4 is a perspective view of a bracket according to an embodiment of the present invention.

FIG. 5 is a perspective view of a bracket according to the embodiment of the present invention.

FIG. 6 is an exploded perspective view of the lid according to the embodiment of the present invention viewed from the lower side.

FIG. 7 is a perspective view of the lid according to the embodiment of the present invention seen from below.

FIG. 8 is an exploded perspective view of a base according to the embodiment of the present invention.

FIG. 9 is a plan view of the base according to the embodiment of the present invention.

FIG. 10 is a sectional view of a plasma cleaning apparatus according to an embodiment of the present invention.

FIG. 11 is a sectional view of a plasma cleaning apparatus according to an embodiment of the present invention.

FIG. 12 is a perspective view of an auxiliary structure of an electrode according to an embodiment of the present invention.

FIG. 13 is an end view of XX in FIG.

FIG. 14 is a plan view showing a conveyance path according to the embodiment of the present invention.

FIG. 15A is an explanatory view of a transfer operation according to an embodiment of the present invention. FIG. 15B is an explanatory view of a transfer operation according to an embodiment of the present invention.

FIG. 16 is a perspective view of a conventional plasma cleaning device.

[Explanation of symbols]

6 target 12 base 13 lid 15 First Arm 16 Second arm 19 vacuum pump 23 cylinders 24 U-arm 25 bracket 26 axes 29 axes 32 first electrode 34 Second electrode 40 guides 41 Guide 60 closed space 61 High frequency application section L transport path

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B08B 7/00

Claims (2)

(57) [Claims] 1. A plasma is generated by decompressing a closed space.
A plasma cleaning device for plasma-cleaning an object in this closed space, which is open to the outside with a horizontal base and a state insulated from the base.
An electrode that is left free, a high-frequency power source that applies a high-frequency voltage to the electrode, a lid that is open at the bottom and that forms a closed space when it contacts the base, and the lid that contacts the base. A contacting / separating means for separating, a conveying means for conveying the object when the lid is separated from the base by the contacting / separating means, and a cooling means for cooling the electrode from below by an air cooling method. A plasma cleaning device characterized by: 2. The plasma cleaning apparatus according to claim 1, wherein the cooling means has a cooling fin that is thermally coupled to a lower portion of the electrode, and a fan that blows air to the cooling fin.