JP2000082692A - Film-type plate-like parts cleaning equipment - Google Patents

Abstract

(57) [Summary] In a conventional method of cleaning and drying by spraying a chemical solution or water while rotating a plate-like component one by one, a chemical solution to be supplied is used in order to reduce the time for foreign matter removal cleaning. There is no method for increasing the flow rate or flow velocity of the solution, and there is a problem that the total amount of the chemical solution used increases. The task is to solve this. In the radial direction of the wafer, the pressure becomes negative compared with the atmospheric pressure. In this portion, the sheet bends in the direction approaching the wafer, and the flow path cross-sectional area is reduced by the amount of the warp. As a result, the foreign matter removing speed increases, so that the time required for the foreign matter removing cleaning can be shortened, and the total amount of the chemical solution used is greatly reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a cleaning apparatus for cleaning a thin plate-shaped component such as a semiconductor wafer, a magnetic recording disk medium, a liquid crystal display panel, and a CRT shadow mask.

[0002]

2. Description of the Related Art A conventional cleaning apparatus is disclosed, for example, in JP-A-8-27.
As described in Japanese Patent No. 4060, a method is known in which a plurality of chucks hold the outer periphery of a plate-shaped component, and while rotating the plate-shaped component one by one, spray a chemical solution, water, and dry gas to wash and dry. I was

[0003]

In the foreign matter removal cleaning of a wafer, there is a correlation between the foreign matter removal speed and the flow rate of the supplied chemical solution. That is, the foreign matter on the wafer is removed when the wafer is etched by the chemical, and is discharged out of the wafer by the newly supplied chemical. Therefore, when the flow rate of the supplied chemical solution is increased, the etching rate of the wafer is increased, and the foreign matter removal rate is also increased. In the above prior art, the only way to shorten the time for removing and cleaning foreign substances is to increase the flow rate of the supplied chemical solution, there is no way to increase the flow rate, and there is a problem that the total amount of chemical solution used increases.

[0004]

In order to solve the above-mentioned problems, in the method of the present invention, the wafer held by a plurality of chucks and the fluid shut-off portion are kept at a narrow interval, and the wafer is turned while the wafer is turned. A chemical solution, water, and a dry gas to be used are supplied to one or both of the back surfaces to perform cleaning and drying. The fluid blocking portion supports a central portion and an outer peripheral portion of a horizontally spread sheet, and has an outlet for a cleaning liquid or the like directed toward a plate-shaped component at a central portion of the fluid blocking portion. The sheet is
The space between the plate-shaped part and the sheet is an elastic member, and the space between the plate-shaped part and the sheet is set to a narrow space where the cleaning liquid can be filled.

When the chemical is supplied to the wafer at a constant flow rate, the supply outlet has a positive pressure, but as the sheet advances in the radial direction of the sheet, the flow velocity increases and becomes a negative pressure as compared with the atmospheric pressure. Further, as the wafer gets closer to the outer periphery, the pressure gradually recovers and becomes atmospheric pressure and is discharged. Since the sheet is supported at the center, the sheet does not bend even if a positive pressure is applied in a direction away from the wafer, and keeps a narrow space between the sheet and the wafer.

Further, as the wafer moves in the radial direction of the wafer,
At this point, the sheet is deflected in a direction approaching the wafer, maintaining a narrower gap with the wafer. At the outer periphery of the wafer, since the atmospheric pressure and the sheet are supported by the fluid blocking portion, the sheet and the wafer keep a narrow space.
Therefore, the flow path cross-sectional area for supplying the chemical liquid is reduced by the amount of the sheet bent by the negative pressure, and the flow velocity of the chemical liquid is increased. As a result, the foreign matter removal speed is increased, so that the time for foreign matter removal cleaning can be shortened, and the total amount of chemical solution used is greatly reduced.

[0007]

FIG. 1 is a longitudinal sectional view of a cleaning head 60 according to a first embodiment of the present invention. FIG. 2 shows a configuration diagram of a cleaning apparatus in which the cleaning head 60 is incorporated.

The upper cleaning unit 1 comprises an upper inlet pipe 2, an upper jet port 3, an upper cleaning film 4, and an upper cleaning support section 5. Although not shown in FIG. 1, the upper cleaning unit 1 is disposed so as to be vertically movable by a vertical drive unit 70 shown in FIG. 2, and is held in an upward direction of the apparatus when the wafer 7 to be cleaned is taken in and out. 0.6 above the wafer during cleaning and drying
mm.

The lower cleaning unit 20 includes a lower cleaning plate 21, a lower jet port 22, a lower introduction pipe 23, and a support shaft 24. The support shaft 24 is fixed to a housing 40, and is used for cleaning and drying. Is held at a position 0.6 mm below the wafer 7.

These upper and lower cleaning units are basically made of a material such as a fluororesin, except that the support shaft 24, the rotating base 34 and the base 36 are made of stainless steel. No attack by chemicals. Since these units do not support high-speed rotation or high load, there is no problem even if they are made of a material having low rigidity such as fluororesin.

A wafer driving unit 30 which rotates and drives the wafer 7 up and down includes chuck pins 31 and
Outer gutter 32, chuck pin elevating and rotating drive unit 3
3, a rotation base 34, a rotation unit 35, and a base 36. The chuck pin 31 has a notch for holding down the wafer 7. When the chuck pin 31 rotates, the wafer 7 is pressed and held by the notch. Further, by rotating the chuck pin 31 after raising it, the wafer 7 is released and can be taken in and out. Further, when the chuck pin 31 grips and lowers the wafer 7, the chuck pin elevating / lowering and rotation driving unit 33 is connected to the rotation base 34, so that the driving force of the rotation unit 35 is transmitted.

The gas-liquid recovery unit 72 collects the chemical solution, water, and dry gas discharged from between the outer gutter 32 and the upper cleaning support unit 5 in the gas-liquid recovery unit 50, and collects them through the gas-liquid recovery pipe 71. . The gas-liquid recovery unit 72 performs a reuse process such as a neutralization process on the recovered chemical solution and water, and then reuses the recovered solution and water as necessary, and partially discards the wastewater. The water to be reused is supplied to the gas-liquid supply unit 75 through the reuse supply pipe 73.
Led to. The gas-liquid supply unit 75 supplies a chemical solution, water, and a dry gas using partially recycled water,
Further, a new chemical solution is prepared.

The gas-liquid switching unit 77 switches the chemical solution, water, and dry gas supplied through the gas-liquid supply pipe 76 as needed, and guides them to the cleaning head 60. Cleaning head 6
The supply of the chemical solution, water, and dry gas to 0 uses the upper introduction pipe 2 for the front surface of the plate-shaped component, and uses the lower introduction pipe 23 for the rear surface.

The upper cleaning film 4 is made of a fluororesin having a thickness of 0.5 mm, and has a central portion and an outer peripheral portion fixed to the upper cleaning supporting portion 5 for installation. Immediately before the cleaning is started, the upper cleaning support 5 is moved by the vertical drive unit 70 to the upper cleaning film 4.
Is held so that the center of the wafer is 1 mm above the wafer 7. A ventilation hole 6 is provided in the upper cleaning support 5, and the upper cleaning film 4 is under atmospheric pressure. When cleaning is started, the wafer 7 is rotated, and from the upper ejection port 3 and the lower ejection port 22,
The chemical is supplied at a pressure of ² kgf / cm ² . Wafer 7
Is uniformly covered with the chemical solution, the upper cleaning support unit 5 is moved by the vertical drive unit 2 so that the center of the upper cleaning film 4 is located 0.6 mm above the wafer 7.

When the chemical solution is supplied to the wafer 7 at a constant flow rate, the outlet of the upper jet port 3 has a positive pressure, but the flow rate increases as the upper cleaning film 4 advances in the radial direction, and the flow rate becomes negative compared with the atmospheric pressure. Pressure. Further, as the wafer 7 approaches the outer periphery of the wafer 7, the pressure gradually recovers and becomes atmospheric pressure and is discharged. Here, the peripheral portion of the upper cleaning film 4 is fixed to the upper cleaning support portion 5, and the distance between the tip of the chuck pin 31 near the upper cleaning film 4 and the upper cleaning film 4 is set to 0.5 mm. The upper cleaning film 4 does not come into contact with the wafer 7 and the chuck pins 31.

Further, since the upper cleaning film 4 has its central portion supported by the upper cleaning supporting portion 5, it does not move in response to an upward pressure near the central portion.
Keep a narrow space of 6mm. Further, as the wafer 7 advances in the radial direction, the pressure becomes negative compared with the atmospheric pressure. In this portion, the upper cleaning film 4 bends downward, and keeps a very narrow gap with the wafer 7. At the outer periphery of the wafer 7, the pressure of the chemical solution is atmospheric pressure, and the upper cleaning film 4 is supported by the upper cleaning support 5, so that a narrow space of 0.5 mm from the wafer 7 is maintained.

Therefore, the cross-sectional area of the flow path in the region of the negative pressure is reduced by the amount by which the upper cleaning film 4 is bent by the negative pressure, and the flow rate of the chemical solution is increased as compared with the conventional cleaning device. As a result, the foreign matter removal speed is increased, so that the time for foreign matter removal cleaning can be shortened, and the total amount of chemical solution used is significantly reduced as compared with a conventional cleaning apparatus.

Note that even if the wafer 7 is bent by the process before cleaning, since the upper cleaning film 4 is an elastic member, if a chemical solution is filled between the wafer 7 and the upper cleaning film 4, Since the pressure received from the chemical solution changes, the bending of the upper cleaning film 4 changes in the same direction as the bending direction of the wafer 7. Therefore, cleaning can be performed without contact between the wafer 7 and the upper cleaning film 4.

While the embodiment of the present invention has been described with reference to the drawings, it is obvious that alternative modifications are possible. FIG. 3 shows a vertical sectional view of the second embodiment.

The lower cleaning unit 100 includes a lower cleaning tank 1
01, lower introduction pipe 23, lower spout 22, lower cleaning film 102,
The lower cleaning unit 100 comprises a lower fluid introduction pipe 103 and a support shaft 24, and is different from the first embodiment.

The main structure of the lower cleaning unit 100 is that a lower cleaning tank 101 is provided below the wafer 7 and has a horizontally extended lower cleaning film 102 in the form of a container having a projection at the center of gravity.
Thus, the central portion and the outer peripheral portion of the lower cleaning film 102 are supported. The lower washing tank 101 is fixed to the support shaft 24. In addition, a lower fluid introduction pipe 103 for supplying and discharging a fluid to be filled in the lower cleaning tank 101 is provided below the lower cleaning tank 101. Further, a lower spout 22 which is a spout of a cleaning liquid or the like is vertically connected to the back surface of the wafer 7 so as to be connected to a lower introduction pipe 23 and installed. The lower cleaning film 102 is a fluororesin having a thickness of 0.5 mm. In addition, it is installed so that the distance between the wafer 7 and the lower ejection port 22 is 0.6 mm.

In this embodiment, the operation of the upper cleaning unit 1 is the same as that of the first embodiment, but the operation of the lower cleaning unit 100 is different. When cleaning is started, the wafer 7 is rotated, and a chemical solution is supplied from the upper jet port 3 and the lower jet port 22 at a pressure of ² kgf / cm ² , and the wafer 7 is uniformly covered with the chemical solution. At this time, using a pump or the like from the lower fluid introduction pipe 103, the fluid is supplied between the lower cleaning tank 101 and the lower cleaning film 102 at a pressure of 3 kgf.
/ Cm ² , and the pressure is transmitted to the lower cleaning film 102. Therefore, if the pressure of the fluid supplied to the lower cleaning tank 101 is set to be higher than the pressure of the chemical liquid supplied to the back surface side of the wafer 7, the portions other than the central portion and the peripheral portion of the lower cleaning film 102 bend upward. , Wafer 7 and lower cleaning film 102
Can be kept very narrow. When the washing is completed, the lower fluid introduction pipe 10 is
From 3, the fluid is discharged.

In this embodiment, as compared with the first embodiment, the cross-sectional area of the flow path of the chemical solution can be made very small on both sides of the wafer, so that the effect of reducing the total amount of chemical solution used is high.

FIG. 4 shows a cleaning state in the third embodiment. Note that, in the present embodiment, unlike the second embodiment, an upper cleaning tank 112 similar to the lower cleaning tank 101 is installed in the upper fluid blocking section 110, and the fluid supply to these cleaning tanks 101 and 112 is performed. A major difference is that the pump is realized by a discharge pressure variable pump.

The lower cleaning unit 100 includes a lower cleaning tank 1
01, lower introduction pipe 23, lower spout 22, lower cleaning film 102,
The lower fluid introduction pipe 103 and the support shaft 24 are configured. The upper cleaning unit 110 includes an upper cleaning tank 112, an upper introduction pipe 2, an upper jet port 3, an upper cleaning film 4, and an upper fluid introduction pipe 11.
And 1.

The structure of the lower cleaning unit 100 is the same as that of the second embodiment.

The upper cleaning unit 110 has the same structure as that of the lower cleaning unit 100, although the arrangement with respect to the wafer 7 is different. Here, the distance between the tip of the chuck pin 31 and the upper cleaning film 4 is set to 0.1 mm even when the distance is reduced during cleaning.
Since 5 mm is secured, there is no contact between the two. Further, the upper cleaning tank 112 and the lower cleaning tank 101
The supply and discharge of fluid to and from the pump are performed using a discharge pressure variable pump.

When cleaning is started, the wafer 7 is rotated, and a chemical solution of 2 kgf / cm ² is supplied from the upper port 3 and the lower port 22.
When the wafer 7 is uniformly covered with the chemical solution, a fluid is supplied to the upper cleaning tank 112 and the lower cleaning tank 101 in a similar manner at a pressure of 3 kgf / cm ² , and the upper cleaning film 4 and the lower cleaning Pressure is transmitted to the membrane 102. If necessary, if the pressure of the fluid supplied to the upper cleaning tank 112 and the lower cleaning tank 101 is set higher, the upper cleaning film 4 and the lower cleaning film 1
Except for the central portion and the peripheral portion of 02, it bends in the direction approaching the wafer 7, and the gap between the wafer 7 and the upper cleaning film 4 and between the wafer 7 and the lower cleaning film 102 can be further narrowed. Since the variable discharge pressure pumps are provided independently for both systems, the upper and lower gaps of the wafer 7 can be set separately according to the required cleanliness of the process.

In this embodiment, since the fluid supplied to the upper cleaning tank 112 and the lower cleaning tank 101 is pressurized by using a variable discharge pressure pump, the supply pressure can be finely adjusted. Since the flow path cross-sectional area of the chemical solution can be further reduced as compared with the example, the flow speed of the chemical solution increases. As a result, the foreign matter removal speed in the front and back surface cleaning is further increased, and the time for the foreign matter removal cleaning can be further reduced.
As a result, the total amount of the chemical solution used is further reduced as compared with the second embodiment. Further, in this embodiment, since the pressure of the fluid supplied to the upper cleaning tank 112 and the lower cleaning tank 101 can be changed independently, the cleanliness required for the front and back surfaces of the wafer 7 and the surface roughness as required are required. It is possible to separately control the foreign matter removal speed on the front and back surfaces of the wafer 7, and it is possible to select a fine cleaning state.

FIG. 5 is a longitudinal sectional view of the fourth embodiment.

This embodiment is different from the first embodiment in that
The upper cleaning unit 120 has an upper cleaning shaft 121, an upper inlet pipe 2, an upper spout 3, a weight 122, an upper cleaning sheet 123, and an outer gutter with a scattering prevention plate instead of the outer gutter 32 in the wafer drive unit 130. 131.
The upper cleaning sheet 123 is made of fluororesin having a thickness of 0.5 mm and has a diameter larger than that of the wafer 7, and a central portion thereof is fixed to the upper cleaning shaft 121. FIG. 6 is a plan view of the upper cleaning unit 120. FIG. The weights 122 installed on the outer peripheral portion of the upper cleaning sheet 123 have a structure in which the weights 122 are evenly spaced. Unlike the upper cleaning support portion 5 in the first embodiment, the upper cleaning shaft 121 in the present embodiment does not have a scattering prevention function. Therefore, instead of the outer gutter 32, an outer gutter 131 with a scattering prevention plate having a scattering prevention function is used. Provided. The outer gutter 131 with the shatterproof plate is a cylindrical shatterproof plate supported by a plurality of struts, and the outer gutter 131 with the shatterproof plate in FIG. 5 is a cross section of two struts at symmetrical positions. Is included.

FIG. 7 shows a change in the shape of the upper cleaning sheet 123. As shown in the operation A, except for the time of cleaning,
A gas such as nitrogen gas is supplied, and the upper cleaning sheet 23
Is spread substantially horizontally due to the pressure of a gas such as nitrogen gas, and is held without contact with the wafer 7 even during descending. In the operation B, the upper cleaning shaft 121 is held by the vertical drive unit 70 such that the bottom of the upper cleaning shaft 121 is located 0.6 mm above the wafer 7.

Here, by lowering the flow rate of gas such as nitrogen gas supplied from the upper jet port 3, the upper cleaning sheet 123
The upper cleaning sheet 123 sinks until it contacts the tip of the chuck pin 31 and the weight 122
The upper cleaning sheet 123 does not wrinkle due to the tension generated by. Therefore, the tip of the chuck pin 31 and the wafer 7
If the distance from the surface of the wafer 7 is set to 0.6 mm, the distance between the upper cleaning sheet 123 and the wafer 7 can be maintained at about 0.6 mm over the entire area of the wafer 7. During the cleaning, the upper cleaning sheet 123 is held by a liquid such as a chemical solution instead of a gas such as a nitrogen gas.

In this embodiment, unlike the other embodiments, the upper cleaning sheet 123 approaches the wafer 7 until it comes into contact with the chuck pins 31. Therefore, there is a disadvantage that the chuck pins 31 and the upper cleaning sheet 123 come into contact with each other during cleaning, but since the height of the upper cleaning sheet 123 is low at the periphery of the wafer 7, the upper cleaning sheet 123 is different from the other embodiments. It approaches the wafer 7 in a wider range as compared. For this reason, the total amount of the chemical solution used is further reduced.

In the above embodiment, the upper cleaning sheet 12
The weights 122 installed on the outer peripheral portion of the third gear 3 have a structure in which the weights 122 are evenly spaced, but instead of the weights 122, a weight having a continuous ring-shaped or chain-shaped or discontinuous frame structure can be used. The same effect can be realized.

[0036]

According to the present invention, there is provided an apparatus for cleaning a thin plate-shaped plate-shaped component such as a semiconductor wafer, a magnetic recording disk medium, a liquid crystal display panel, and a cathode ray tube shadow mask. Alternatively, by keeping the space between the plate-shaped component and the fluid shut-off portion that restricts the flow of the fluid installed on both sides narrow, the total amount of the chemical solution used on one or both of the front and back surfaces can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a cleaning head according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a cleaning apparatus according to the first embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a cleaning head according to a second embodiment of the present invention.

FIG. 4 is a sectional view of a third embodiment of the present invention in a cleaning state of a plate-like component.

FIG. 5 is a vertical sectional view of a cleaning head according to a fourth embodiment of the present invention.

FIG. 6 is an upper cleaning head 1 according to a fourth embodiment of the present invention.
20 is a plan view.

FIGS. 7A to 7C are cross-sectional views showing a change in the shape of an upper cleaning head 120 according to a fourth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Upper cleaning unit, 2 ... Upper introduction pipe, 3 ... Upper ejection port, 4 ... Upper cleaning film, 5 ... Upper cleaning support part, 6
... vent holes, 7 ... wafers, 20 ... lower cleaning unit,
21: lower washing plate, 22: lower spout, 23: lower inlet pipe,
24: Support shaft, 30: Wafer drive unit, 31: Chuck pin, 32: Outer gutter, 33
... Chuck pin lifting / lowering and rotation drive unit, 34 ... Rotation base, 35 ... Rotation unit, 36 ... Base, 40
... housing, 50 ... gas-liquid recovery unit, 60 ... washing head, 70 ... vertical drive unit, 71 ... gas-liquid recovery pipe, 7
2: gas-liquid recovery unit, 73: reuse supply pipe, 74
... drain pipe, 75 ... gas-liquid supply unit, 76 ... gas-liquid supply pipe, 77 ... gas-liquid switching unit, 100 ... lower cleaning unit, 101 ... lower cleaning tank, 102 ... lower cleaning film,
103: lower fluid introduction pipe, 110: upper cleaning unit, 1
11 ... upper fluid introduction pipe, 112 ... upper cleaning tank, 120
... upper cleaning unit, 121 ... upper cleaning shaft, 122 ... weight,
123: Upper cleaning sheet, 130: Wafer drive unit, 131: Outer gutter with shatterproof plate.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoichi Takahara 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Hitachi, Ltd. Production Technology Research Institute (72) Inventor Susumu Aiuchi 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Address F-term in Hitachi, Ltd. Production Research Laboratory (reference) 3B201 AA03 AB08 AB34 BB62 BB87 BB90 BB92 BB95 CB01 CC01 CC12 CD22

Claims (7)

[Claims] In a cleaning apparatus for a plate-shaped component, a fluid shut-off portion is provided so as to face one or both of the front and back surfaces of the plate-shaped component, and one of the plate-shaped component and the fluid cut-off portion is provided.
Or, by moving both relatively, a moving mechanism installed at a narrow space between the plate-shaped component and the fluid shut-off portion can be filled with a cleaning liquid, the fluid shut-off portion, the plate-shaped A jet port such as a cleaning liquid is provided facing the component, and further, an elastic member is provided in the fluid blocking portion in parallel with the plate-shaped component, and a pressure difference is generated between the front and back surfaces of the elastic member, thereby forming the elastic member. A film-type plate-like part cleaning device having a bending mechanism. 2. The film-type plate-like component cleaning apparatus according to claim 1, wherein the pressure of the cleaning liquid between the plate-like component and the elastic member is lower than atmospheric pressure, and the pressure is applied to the front and back surfaces of the elastic member. A cleaning device for a film-type plate-shaped part, comprising: a mechanism for generating a pressure difference to bend the elastic member. 3. The apparatus according to claim 1, wherein the pressure of the cleaning liquid between said plate-like component and said elastic member is lower than the atmospheric pressure, and said elastic member is compressed by a pressurized fluid. And a mechanism for applying a positive pressure to the elastic member to deflect the elastic member. 4. The cleaning device according to claim 2, wherein the fluid blocking portion is provided with the elastic member in parallel with at least one of the front and back surfaces of the plate component. A cleaning device for film-type plate-shaped parts, characterized by the following. 5. The film-type plate-like component cleaning apparatus according to claim 3, wherein the fluid blocking portion is provided with the elastic member in parallel with both the front and back surfaces of the plate-like component. Film type plate cleaning equipment. 6. The film-type plate-like component cleaning apparatus according to claim 3, further comprising a mechanism that varies a pressure applied to the elastic member. 7. An apparatus according to claim 2, wherein said elastic member has an outer diameter larger than a diagonal dimension of said plate-shaped component, and further comprises an outer peripheral portion of said elastic member. A film-type plate-like part cleaning apparatus characterized in that a weight is installed.