Etching apparatus and wafer support

Abstract

The present invention provides an etching apparatus and a wafer support that suppresses the scattering of cleaning water during wet etching. A wafer (W) to be subjected to wet etching is supported by a wafer support (3) having a gap. Also, a cleaning unit (31) recovers cleaning water that flows down from the gap of the wafer support (3) by a cleaning liquid bottle (32) disposed below the wafer support (3) when cleaning the upper surface of the wafer (W) supported by the wafer support (3) with cleaning water. Thus, the cleaning water can be recovered well while suppressing the scattering of the cleaning water to the surroundings of the wafer (W).

Description

Technical Field

[0001] The present invention relates to etching apparatus and wafer supports. Background Art

[0002] Wet etching is disclosed in Patent Documents 1 to 3. In wet etching, an etching liquid is supplied to the upper surface of a silicon wafer to etch the upper surface of the wafer.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 02-086130

[0004] Patent Document 2: Japanese Patent Application Laid-Open No. 06-265869

[0005] Patent Document 3: Japanese Patent Application Laid-Open No. 2017-028257

[0006] Conventionally, after etching, the cleaning water used to clean the wafer scatters around the wafer, and a large waste liquid treatment device is required to recover the scattered cleaning water. Summary of the Invention

[0007] An object of the present invention is to provide an etching apparatus and a wafer support member capable of suppressing scattering of cleaning water during wet etching.

[0008] The etching device of the present invention (this etching device) is a wet etching device for wet etching a wafer supported by a wafer support, wherein the etching device includes: an etching unit that accumulates etching liquid on the upper surface of the wafer supported by the wafer support and etches the upper surface of the wafer; a cleaning unit that cleans the upper surface of the wafer supported by the wafer support with cleaning water; a drying unit that rotates the wafer supported by the wafer support and dries the wafer; and a storage chamber that stores the etching unit, the cleaning unit and the drying unit, the wafer support having a main body and legs, the main body including: a base that partially contacts the lower surface of the wafer to place the wafer thereon; and a plurality of columns that are upright on the base in a manner surrounding the wafer placed on the base, the legs extending outward from the main body, the cleaning unit being configured to recover the cleaning water that flows down from the gap in the wafer support, and the etching device etches the upper surface of the wafer.

[0009] In addition, the etching apparatus may further include a cleaning unit for maintaining the cleanliness of the storage chamber, and the storage chamber may include an outlet for discharging gas from the storage chamber and an inlet for allowing gas to enter the storage chamber.

[0010] The cleaning unit may include: a pipe for allowing the gas to flow from the outlet to the inlet; a fan arranged in the pipe; a harm removal unit arranged in the pipe for removing toxic components of the gas; and a filter arranged between the harm removal unit and the inlet in the pipe for removing dust contained in the gas.

[0011] In addition, in the present etching device, the etching unit may include: an etching liquid supply part, which drips a specified amount of etching liquid onto the upper surface of the wafer supported by the wafer support to form an etching liquid layer by utilizing surface tension; and an etching liquid recovery part, which absorbs the etching liquid from the upper surface of the wafer after etching. The cleaning unit may include: a first bottle, which has an opening at the top, the opening is larger than the diameter of the wafer, and can be engaged with the wafer support by means of the legs; and a cleaning water supply part, which supplies cleaning water to the upper surface of the wafer supported by the wafer support engaged with the opening of the first bottle. The drying unit may include: a holding workbench, which holds the wafer support and suction-holds the lower surface of the wafer; and a rotating part, which rotates the holding workbench to dry the wafer.

[0012] In this case, the etching device may further include a mask layer removal unit in the storage chamber for removing the mask layer formed on the upper surface of the chip, and the mask layer removal unit may include: a second bottle having an opening at the top, the opening being larger than the diameter of the chip and capable of engaging the chip support with the help of the legs; a first liquid supply part, which supplies the first liquid to the upper surface of the chip supported by the chip support engaged with the opening of the second bottle; and a second liquid supply part, which supplies the second liquid to the upper surface of the chip.

[0013] In addition, in this etching device, there can be a transport unit in the storage chamber for transporting the chip support supporting the chip, and the transport unit can have: a claw that hooks the leg of the chip support to hold it; a horizontal moving unit that moves the claw in the horizontal direction; and a lifting unit that lifts and lowers the claw.

[0014] The chip support of the present etching device (the present chip support) supports the chip, wherein the chip support has a main body and legs, the main body including: a base, which is in partial contact with the lower surface of the chip to place the chip thereon; and a plurality of columns, which are erected on the base in a manner surrounding the chip placed on the base, and the legs extend outward from the main body.

[0015] In this etching apparatus, the wafer undergoing wet etching is supported by a wafer support having a gap therein. Furthermore, the cleaning unit is configured to recover cleaning water that overflows from the upper surface of the wafer and flows down through the gap in the wafer support while cleaning the wafer supported by the wafer support. Therefore, by pre-arranging a recovery container below the wafer support, this etching apparatus can effectively recover the cleaning water while suppressing the cleaning water from scattering around the wafer.

[0016] Furthermore, the etching apparatus may include a cleaning unit for maintaining the cleanliness of the storage chamber, as described above. This removes toxic components and dust from the gas circulating within the storage chamber, thereby maintaining its cleanliness. This facilitates maintaining the cleanliness of the storage chamber.

[0017] In addition, in the present etching apparatus, the etching unit may include: an etching liquid supply unit that forms an etching liquid layer on the upper surface of the wafer using surface tension; and an etching liquid recovery unit that draws the etching liquid from the upper surface of the wafer after etching.

[0018] In this structure, etching is performed by accumulating the etching liquid on the upper surface of the wafer due to surface tension, thereby reducing the amount of etching liquid used. Furthermore, after etching, the etching liquid is sucked out and recovered, thereby preventing the etching liquid from scattering around the wafer. Furthermore, while the recovered etching liquid may increase the etching time, it can be reused. Consequently, the frequency of using waste liquid treatment equipment for treating the etching liquid can be reduced.

[0019] Furthermore, in this etching apparatus, the cleaning unit can include, as described above, a first bottle having an opening that engages with the wafer support, and a cleaning water supply unit that supplies cleaning water to the upper surface of the wafer. In this configuration, the cleaning water that overflows from the wafer and flows through the gaps in the wafer support can be recovered by the first bottle. This facilitates the recovery of the cleaning water.

[0020] In this embodiment, the drying unit may include a holding table for holding the wafer support and the wafer, and a rotating unit for rotating the holding table, as described above. This allows the wafer to be dried easily.

[0021] Furthermore, the wet etching apparatus may further include a mask layer removal unit in the storage chamber as described above, thereby making it possible to easily remove the mask from the wafer.

[0022] Alternatively, the mask layer removal unit may include a second bottle having an opening at its top similar to that of the first bottle, and a first and second liquid supply units for supplying the first and second liquids to the upper surface of the wafer. With this configuration, the second bottle can recover the first and second liquids, as well as the dissolved material in the mask, that flow down through the gap in the wafer support. This allows for easy recovery of the first and second liquids, as well as the dissolved material, while preventing them from scattering around the wafer.

[0023] Furthermore, conventionally, etching of wafers is performed by supplying an etching liquid, cleaning water, a first liquid, or a second liquid to the wafer and causing the etching liquid, cleaning water, the first liquid, and the second liquid to splash from the wafer. In this case, a large clean room of a size that allows operators to work inside is used to accommodate the etching unit, cleaning unit, and mask layer removal unit.

[0024] On the other hand, in this wet etching apparatus, liquid is supplied to the wafer and then sucked off the wafer for recovery. Liquid flowing down from the gaps in the wafer support is recovered using a bottle. This significantly reduces the size of the etching unit, cleaning unit, and mask layer removal unit. These units and the drying unit can thus be housed in a compact storage chamber. This eliminates the need for a large clean room and significantly reduces the size and cost of this wet etching apparatus.

[0025] Furthermore, the wet etching apparatus may further include a transport unit for transporting a wafer support within the storage chamber as described above, thereby making it possible to easily transport the wafer support supporting the wafer between the etching unit, the cleaning unit, the mask layer removal unit, and the drying unit.

[0026] The wafer support comprises a main body and legs. The main body includes a base that partially contacts the lower surface of a wafer to support the wafer, and a plurality of columns that are erected on the base to surround the wafer placed on the base. The legs extend outward from the main body. Using this wafer support allows liquid (rinsing water, first liquid, second liquid, etc.) supplied to a wafer placed on the base of the wafer support to flow out through gaps in the wafer support. This facilitates liquid recovery by pre-arranging recovery containers such as the first and second bottles below the wafer support. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is an explanatory diagram showing the structure of a wet etching apparatus.

[0028] Figure 2 It is a perspective view showing a wafer support.

[0029] Figure 3 It is a perspective view showing a wafer support on which a wafer is placed.

[0030] Figure 4 It is an explanatory diagram showing the structure of the etching unit.

[0031] Figure 5 It is an explanatory diagram showing the structure of the etching liquid bottle.

[0032] Figure 6 It is an explanatory diagram showing the structure of the cleaning unit.

[0033] Figure 7 It is an explanatory diagram showing the structure of the mask layer removal unit.

[0034] Figure 8 It is an explanatory diagram showing the structure of the drying unit.

[0035] Figure 9 It is a perspective view showing the structure of the drying unit.

[0036] Figure 10 It is an explanatory diagram showing the structure of the transport unit.

[0037] Description of labels

[0038] 1: Wet etching device; 3: Wafer support; 4: Main body; 5: Base; 6: Column; 8: Leg; 11: Storage chamber; 12: Outlet; 13: Inlet; 21: Etching unit; 22: Etching liquid bottle; 22a: Opening; 23: Etching liquid supply unit; 24: Etching liquid supply nozzle; 25: Etching liquid supply nozzle lifting unit; 26: Etching liquid recovery unit; 27: Etching liquid recovery nozzle; 28: Etching liquid recovery nozzle lifting unit; 31: Cleaning unit; 32: Cleaning liquid bottle; 32a: Opening; 33: Cleaning water supply unit; 34: Cleaning water supply nozzle; 35: Cleaning water supply nozzle lifting unit; 41: Mask layer removal unit; 42: Mask layer removal bottle; 42a: Opening : Mouth; 43: First liquid supply portion; 44: First liquid supply nozzle; 45: First liquid supply nozzle lifting unit; 46: Second liquid supply portion; 47: Second liquid supply nozzle; 48: Second liquid supply nozzle lifting unit; 51: Drying unit; 53: Holding table; 54: Bottom portion; 55: Support column pair; 56: Holding surface; 57: Rotating portion; 59: Motor; 61: Transport unit; 62: Claw; 63: Rotating unit; 64: Arm; 65: Lifting unit; 66: Horizontal moving unit; 71: Cleaning unit; 72: Piping; 73: Fan; 75: Dust filter; 74: Pest control unit; 82: Water supplier; 83: Water source; 84: Discharge outlet; 85: Pest control filter. DETAILED DESCRIPTION

[0039] Figure 1The wet etching apparatus 1 of the present embodiment shown is an apparatus for wet etching a wafer W supported by a wafer support 3. The wafer W to be wet etched in the present embodiment has a small diameter (eg, about 1 inch).

[0040] First, the structure of the wafer support 3 will be described. Figure 2 and Figure 3 As shown, the wafer support 3 has a main body 4 that supports the wafer W. The main body 4 includes a base 5 on which the wafer W is placed, a plurality of columns 6 erected on the base 5 , and a ring 7 that connects the upper ends of the columns 6 .

[0041] The base 5 has a diameter slightly larger than that of the wafer W. The base 5 has a mesh shape having a frame portion (rib portion) 5 a and holes 5 b serving as gaps between the frame portion 5 a. The base 5 holds the wafer W in a state of partial contact with the lower surface of the wafer W. The pillar portion 6 is erected on the outer periphery of the base 5 so as to surround the wafer W placed on the base 5 .

[0042] The wafer support 3 also has a plurality of legs 8 extending outward from the main body 4. In this embodiment, six legs 8 extend outward from the column 6 of the main body 4. Each leg 8 has a stopper 9 extending downward at its distal end.

[0043] Next, the structure of the wet etching device 1 will be described. Figure 1 As shown, the wet etching apparatus 1 includes a storage chamber 11 serving as a housing of the wet etching apparatus 1. The storage chamber 11 is a so-called glove box (a small ventilation chamber) and is a sealed container in which only hands can be placed so that work can be performed while being isolated from the outside air.

[0044] The storage chamber 11 houses an etching unit 21, a cleaning unit 31, a mask layer removal unit 41, and a drying unit 51 arranged along its length. Furthermore, a transport unit 61 for transporting the wafer support 3 supporting the wafer W is mounted above the storage chamber 11.

[0045] When the hand is not placed in the storage chamber 11 using the glove box, the wafer support 3 supporting the wafer W is transported by the transport unit 61 .

[0046] In addition, the side wall of the storage chamber 11 has: an inlet 101, which is used to carry the chip support 3 supporting the chip W into the storage chamber 11; a door 102, which is used to open and close the inlet 101; and a door opening and closing unit (cylinder) 103, which is used to open and close the door 102.

[0047] Figure 4The etching unit 21 shown in FIG. 1 accumulates etching liquid on the upper surface of the wafer W supported by the wafer support 3 and etches the upper surface of the wafer W. Figure 4 As shown, the etching unit 21 includes an etching liquid bottle 22 for placing the wafer support 3, an etching liquid supply unit 23 for supplying the etching liquid, and an etching liquid recovery unit 26 for recovering the etching liquid.

[0048] like Figure 4 and Figure 5 As shown in FIG. 1 , the etching liquid bottle 22 has an opening 22a at the top. The opening 22a is larger than the diameter of the wafer W and is formed so as to be able to engage with the wafer support 3 via the legs 8. Figure 5 As shown, the wafer support 3 supporting the wafer W is engaged with the opening 22 a of the etching liquid bottle 22 via the legs 8 having the stoppers 9 .

[0049] like Figure 4 As shown, the etching liquid supply unit 23 includes an etching liquid supply nozzle 24 for supplying etching liquid and an etching liquid supply nozzle lifting unit 25 for vertically moving the etching liquid supply nozzle 24. The etching liquid supply nozzle 24 can communicate with an etching liquid supply source ES.

[0050] In the etching liquid supply unit 23, the etching liquid supply nozzle 24 is positioned at a predetermined height by the etching liquid supply nozzle lifting unit 25. Furthermore, the etching liquid supply nozzle 24 is connected to the etching liquid supply source ES, and a predetermined amount of etching liquid is dripped from the etching liquid supply nozzle 24 onto the upper surface of the wafer W supported by the wafer support 3. As a result, the etching liquid supply unit 23 forms an etching liquid layer EL on the upper surface of the wafer W due to surface tension. The etching liquid layer EL is then formed and the unit waits for approximately three minutes. Thus, the upper surface of the wafer W is etched (chemical processing).

[0051] like Figure 4 As shown, the etching liquid recovery unit 26 includes an etching liquid recovery nozzle 27 for recovering the etching liquid and an etching liquid recovery nozzle lifting unit 28 for vertically moving the etching liquid recovery nozzle 27. The etching liquid recovery nozzle 27 can communicate with the suction source EV.

[0052] In the etching liquid recovery unit 26, after etching, the etching liquid recovery nozzle 27 is positioned by the etching liquid recovery nozzle lifting unit 28 at a height where it contacts the etching liquid layer EL formed on the upper surface of the wafer W. Furthermore, the etching liquid recovery nozzle 27 is connected to the suction source EV and draws the etching liquid that has formed the etching liquid layer EL up from the upper surface of the wafer W. The etching liquid drawn up by the etching liquid recovery nozzle 27 is accumulated in an etching liquid recovery bottle (not shown) and recovered.

[0053] The etching liquid that is not completely recovered by the etching liquid recovery unit 26 overflows from the upper surface of the wafer W and flows into the etching liquid bottle 22 through the gaps in the wafer support 3 as shown by arrow A, where it is accumulated and recovered. The gaps in the wafer support 3 include, for example, the gaps between the plurality of pillars 6 and the hole 5b of the base 5 (see FIG. Figure 2 ).

[0054] The etching solution is, for example, a mixture of acetic acid, nitric acid, and phosphoric acid. The amount of the etching solution used to form the etching solution layer EL is, for example, 0.3 mL. The recovered etching solution is also approximately the same amount.

[0055] Figure 6 The cleaning unit 31 shown cleans the upper surface of the wafer W supported by the wafer support 3 with cleaning water. Figure 6 As shown, the cleaning unit 31 includes a cleaning liquid bottle 32 for placing the wafer support 3 thereon and a cleaning water supply unit 33 for supplying cleaning water.

[0056] The cleaning liquid bottle 32 has the same structure as the etching liquid bottle 22. Figure 5 and Figure 6 As shown in FIG. 1 , the cleaning liquid bottle 32 has an opening 32a at the top. The opening 32a is larger than the diameter of the wafer W and is formed so as to be able to engage with the wafer support 3 via the legs 8. That is, in the cleaning unit 31, as shown in FIG. Figure 5 As shown, the wafer support 3 supporting the wafer W is engaged with the opening 32a of the cleaning liquid bottle 32 via the legs 8 having the stoppers 9. The cleaning liquid bottle 32 corresponds to an example of a first bottle.

[0057] like Figure 6 As shown, the washing water supply unit 33 includes a washing water supply nozzle 34 for supplying washing water and a washing water supply nozzle lifting unit 35 for vertically moving the washing water supply nozzle 34. The washing water supply nozzle 34 can communicate with a washing water supply source WS.

[0058] In the cleaning water supply unit 33, a cleaning water supply nozzle 34 is positioned at a predetermined height by a cleaning water supply nozzle lifting unit 35. Furthermore, the cleaning water supply nozzle 34 is connected to a cleaning water supply source, and cleaning water is supplied from the cleaning water supply nozzle 34 to the upper surface of the wafer W supported by the wafer support 3 (e.g., by pulsed water supply). Thus, the upper surface of the wafer W is cleaned with the cleaning water.

[0059] The cleaning water used in cleaning overflows from the upper surface of the wafer W and flows through the gap of the wafer support 3 as shown by arrow B into the cleaning liquid bottle 32, where it is accumulated and recovered. In this way, the cleaning unit 31 recovers the cleaning water flowing down from the gap of the wafer support 3.

[0060] Figure 7 The mask layer removal unit 41 shown removes the mask layer (not shown) made of resin formed on the upper surface of the wafer W. Figure 7 As shown, the mask layer removal unit 41 includes: a mask layer removal bottle 42 for placing the chip support 3; a first liquid supply part 43 for supplying a first liquid as an organic solvent; and a second liquid supply part 46 for supplying a second liquid (mask removal liquid) as another organic solvent.

[0061] The mask layer removal bottle 42 has the same structure as the etching solution bottle 22. Figure 5 and Figure 7 As shown, the mask layer removal bottle 42 has an opening 42a at the top. The opening 42a is larger than the diameter of the wafer W and is formed so as to be able to engage with the wafer support 3 via the legs 8. That is, in the mask layer removal unit 41, as shown in FIG. Figure 5 As shown, the wafer support 3 supporting the wafer W is engaged with the opening 42a of the mask layer removing bottle 42 via the legs 8 having the stoppers 9. The mask layer removing bottle 42 corresponds to an example of a second bottle.

[0062] like Figure 7 As shown, the first liquid supply unit 43 includes a first liquid supply nozzle 44 for supplying the first liquid and a first liquid supply nozzle lifting unit 45 for vertically moving the first liquid supply nozzle 44. The first liquid supply nozzle 44 is communicable with a first liquid supply source S1. The first liquid is an alcohol-based liquid, such as ethanol or isopropyl alcohol.

[0063] In the first liquid supply unit 43, a first liquid supply nozzle 44 is positioned at a predetermined height by a first liquid supply nozzle elevating unit 45. Furthermore, the first liquid supply nozzle 44 is connected to a first liquid supply source S1, and the first liquid is supplied from the first liquid supply nozzle 44 to the upper surface of the wafer W supported by the wafer support 3. As a result, moisture on the upper surface of the wafer W is replaced with the alcohol-based first liquid.

[0064] like Figure 7 As shown, the second liquid supply unit 46 includes a second liquid supply nozzle 47 for supplying the second liquid and a second liquid supply nozzle lifting unit 48 for vertically moving the second liquid supply nozzle 47. The second liquid supply nozzle 47 can communicate with the second liquid supply source S2. The second liquid is, for example, acetone.

[0065] In the second liquid supply unit 46, a second liquid supply nozzle 47 is positioned at a predetermined height by a second liquid supply nozzle elevating unit 48. Furthermore, the second liquid supply nozzle 47 is connected to a second liquid supply source S2, and the second liquid is supplied from the second liquid supply nozzle 47 to the upper surface of the wafer W supported by the wafer support 3. This dissolves the resin mask layer, thereby removing the mask layer.

[0066] The first and second liquids supplied to the upper surface of the wafer W, as well as the dissolved resin, overflow from the upper surface of the wafer W and flow through the gap in the wafer support 3 as indicated by arrow C into the mask layer removal bottle 42, where they are accumulated and recovered. In this manner, the mask layer removal unit 41 recovers the first and second liquids and the dissolved resin that have flowed down from the gap in the wafer support 3.

[0067] Figure 8 and Figure 9 The drying unit 51 shown rotates and dries the wafer W supported by the wafer support 3. Figure 8 and Figure 9 As shown, the drying unit 51 includes a holding table 53 for holding the wafer support 3 and a rotating unit 57 for rotating the holding table 53 in a container 52 .

[0068] The holding table 53 holds the wafer support 3 that supports the wafer W, and also suctions and holds the lower surface of the wafer W. The rotating unit 57 rotates the holding table 53 to dry the wafer W.

[0069] The holding table 53 includes an annular bottom portion 54 , a plurality of support column pairs 55 erected on the bottom portion 54 , and a holding surface 56 fixed to the center of the bottom portion 54 .

[0070] The bottom portion 54 has a larger diameter than the base 5 of the wafer support 3. The support post pair 55 is formed of two support posts 55a and is provided upright on the outer periphery of the bottom portion 54. The support post pair 55 is configured to sandwich the legs 8 of the wafer support 3 between the two support posts 55a. Therefore, in this embodiment, six support post pairs 55 are provided upright on the bottom portion 54 to correspond to the six legs 8 of the wafer support 3.

[0071] The holding surface 56 is made of a porous ceramic material and communicates with a suction source (not shown) to suction-hold the wafer W placed on the base 5 of the wafer support 3 via the base 5 .

[0072] The rotating portion 57 includes a motor 59 within a housing 58. A spindle 59a of the motor 59 is coupled to the lower surface of the holding surface 56 of the holding table 53. The wafer W is held on the holding surface 56 such that the rotation axis of the motor 59 (the center of the spindle 59a) passes through the center of the wafer W.

[0073] In the holding table 53, the holding table 53 holding the wafer support 3 is rotated integrally (at a rotation speed of, for example, 7500 rpm) by the motor 59 of the rotating unit 57. As a result, the wafer W supported by the wafer support 3 and held by the holding surface 56 of the holding table 53 is rotated about, for example, the center of the wafer W. As a result, the liquid (e.g., the first liquid and the second liquid) remaining on the upper surface of the wafer W is vaporized, drying the upper surface of the wafer W.

[0074] Figure 1 The transport unit 61 shown transports the wafer support 3 supporting the wafer W between the etching unit 21 , the cleaning unit 31 , the mask layer removal unit 41 , and the drying unit 51 .

[0075] In the upper portion of the storage chamber 11, rails R are arranged above each of the units 21, 31, 41, and 51, parallel to the direction in which these units are arranged, that is, the longitudinal direction of the storage chamber 11. The transport unit 61 is mounted on the rails R so as to be movable along the rails R. Therefore, the transport unit 61 can reciprocate along the rails R above each of the units 21, 31, 41, and 51.

[0076] like Figure 10 As shown, the conveying unit 61 includes: a claw 62 for holding the chip support 3; a rotating unit 63 for rotating the claw 62; an arm 64 for supporting the claw 62 and the rotating unit 63; a lifting unit 65 for moving the arm 64, the rotating unit 63 and the claw 62 in the up and down directions; and a horizontal moving unit 66 for moving the conveying unit 61 as a whole including the claw 62 in the horizontal direction along the track R.

[0077] The claw portion 62 has a substantially U-shaped structure and includes a base portion 62b extending horizontally and two claws 62a extending downward from both ends of the base portion 62b. The claw portion 62 hooks the leg 8 of the wafer support 3 (see FIG. Figure 2 ) and maintain it.

[0078] The rotating unit 63 is attached to the base 62b of the claw 62. The rotating unit 63 rotates about a rotation axis L extending in the vertical direction as indicated by an arrow La. As a result, the claw 62 (claw 62a) rotates as indicated by an arrow Lb.

[0079] The arm 64 supports the rotating unit 63 and the claw 62 at its front end. A lifting unit 65 is attached to the base end of the arm 64. The lifting unit 65 is moved vertically within the horizontal moving unit 66 by a drive mechanism (not shown) within the horizontal moving unit 66. Thus, the lifting unit 65 can move the arm 64, the rotating unit 63, and the claw 62 upward and downward as indicated by the double-headed arrow U.

[0080] The horizontal moving unit 66 holds the lifting unit 65 therein and is horizontally moved along the rail R by a driving mechanism (not shown). Thus, the horizontal moving unit 66 can horizontally move the entire transport unit 61 including the claw 62 along the rail R as indicated by the double arrow T.

[0081] During the etching operation of the wet etching apparatus 1 , the transport unit 61 or an operator places the wafer support 3 supporting the wafer W on the etching liquid bottle 22 of the etching unit 21 .

[0082] After etching, the transport unit 61 moves horizontally to above the etching unit 21, lowers the claws 62, and uses the claws 62 (claws 62a) to hook the legs 8 of the wafer support 3 and hold it. The transport unit 61 raises the claws 62 holding the wafer support 3 and moves horizontally to above the cleaning unit 31. The claws 62 are lowered to place the wafer support 3 on the cleaning liquid bottle 32. In this way, the transport unit 61 transports the wafer support 3 between the units 21, 31, 41, and 51.

[0083] In addition, if Figure 1 As shown, the receiving chamber 11 has an outlet 12 for discharging gas from the receiving chamber 11 and an inlet 13 for allowing gas to enter the receiving chamber 11 .

[0084] The outlet 12 is provided below the side wall near the drying unit 51 in the storage chamber 11. The inlet 13 is formed in the upper portion of the storage chamber 11 along the longitudinal direction of the storage chamber 11, for example, in a groove shape.

[0085] The wet etching apparatus 1 further includes a cleaning unit 71 for maintaining the cleanliness of the storage chamber 11. The cleaning unit 71 includes a pipe 72. The pipe 72 connects the outlet 12 and the inlet 13 and allows gas to flow from the outlet 12 to the inlet 13. The cleaning unit 71 further includes a fan 73, a detoxification unit 74, and a dust filter 75, which are disposed on the pipe 72.

[0086] The fan 73 creates a flow of gas from the outlet 12 toward the inlet 13 in the pipe 72 .

[0087] The detoxification unit 74 removes the toxic components of the gas in the pipe 72. Figure 1 As shown, the harm removal unit 74 has a housing 81 for taking in the gas in the pipe 72 and discharging. In addition, the harm removal unit 74 has a water provider 82, a harm removal filter 85 and an outlet 84 for discharging the water provided by the water provider 82 in the housing 81 and being communicated with an external water source 83.

[0088] The harm removal unit 74 having such a structure removes toxic components from the gas taken in by the pipe 72 using water, water droplets WL provided by the water supplier 82 and the harm removal filter 85, and returns the gas to the pipe 72. The used water is discharged to the outside of the housing 81 through the discharge port 84 as shown by the arrow D.

[0089] The gas from which the toxic components have been removed passes through a dust filter 75 disposed between the detoxification unit 74 and the inlet 13 via a fan 73. The dust filter 75 removes dust contained in the gas passing through the dust filter 75 itself. The gas that has passed through the dust filter 75 returns to the storage chamber 11 via the inlet 13.

[0090] As described above, in this embodiment, the wafer W to be wet-etched is supported by a substrate having gaps (between the pillars 6 and the hole 5b of the base 5; see Figure 2 ) chip support 3.

[0091] Furthermore, the cleaning unit 31 is configured to recover cleaning water that overflows from the upper surface of the wafer W and flows down through the gaps in the wafer support 3 when the wafer W supported by the wafer support 3 is cleaned with cleaning water. Therefore, in this embodiment, a recovery container (cleaning liquid bottle 32) is pre-placed below the wafer support 3, thereby enabling efficient recovery of the cleaning water while suppressing scattering of the cleaning water around the wafer W.

[0092] In this embodiment, wet etching apparatus 1 includes cleaning unit 71 for maintaining cleanliness in storage chamber 11. This removes toxic components and dust from gas circulating in storage chamber 11 to maintain its cleanliness, making it easy to maintain cleanliness in storage chamber 11.

[0093] In addition, in this embodiment, the etching unit 21 has: an etching liquid supply part 23, which uses surface tension to form an etching liquid layer on the upper surface of the chip W supported by the chip support 3; and an etching liquid recovery part 26, which absorbs the etching liquid from the upper surface of the chip W after etching.

[0094] Thus, in this embodiment, etching is performed by accumulating the etching liquid on the upper surface of the wafer W using surface tension, thereby reducing the amount of etching liquid used. Furthermore, after etching, the etching liquid is sucked out and recovered, thereby preventing the etching liquid from scattering around the wafer W. Furthermore, while the recovered etching liquid may increase the etching time, it can be reused. Consequently, the frequency of using waste liquid treatment equipment for treating the etching liquid can be reduced.

[0095] In this embodiment, the cleaning unit 31 includes a cleaning liquid bottle 32 having an opening 32a at its top. Furthermore, the cleaning unit 31 includes a cleaning water supply unit 33 for supplying cleaning water to the upper surface of the wafer W supported by the wafer support 3 engaged with the opening 32a of the cleaning liquid bottle 32.

[0096] By engaging the legs 8 of the wafer support 3 with the opening 32a of the cleaning liquid bottle 32, the wafer W can be placed in the center of the opening 32a of the cleaning liquid bottle 32. In other words, the wafer W can be placed in the center of the opening 32a so as to be suspended in the air.

[0097] Therefore, in the cleaning unit 31, the cleaning liquid that overflows from the wafer W and flows down from the gap of the wafer support 3 can be recovered by the cleaning liquid bottle 32. Therefore, the cleaning water can be easily recovered.

[0098] In this embodiment, the drying unit 51 includes a holding table 53 that holds the wafer support 3 and suction-holds the lower surface of the wafer W, and a rotating unit 57 that rotates the holding table 53 to dry the wafer W. This facilitates drying the wafer W. In particular, in this embodiment, the support column pair 55 of the holding table 53 clamps the legs 8 of the wafer support 3. This effectively prevents the wafer W from falling from the holding table 53 due to centrifugal force during rotation.

[0099] In this embodiment, the wet etching apparatus 1 further includes a mask layer removal unit 41 within the storage chamber 11 for removing a resin mask layer formed on the upper surface of the wafer W. The mask layer removal unit 41 includes a mask layer removal bottle 42 having an opening 42a at its upper portion. The mask layer removal unit 41 also includes a first liquid supply unit 43 for supplying a first liquid to the upper surface of the wafer W supported by the wafer support 3 engaged with the opening 42a of the mask layer removal bottle 42, and a second liquid supply unit 46 for supplying a second liquid to the upper surface of the wafer W.

[0100] Therefore, in the mask layer removal unit 41, the first liquid, the second liquid, and the dissolved resin that have overflowed from the wafer W and flowed down through the gap in the wafer support 3 can be recovered by the mask layer removal bottle 42. Therefore, the first liquid, the second liquid, and the dissolved resin can be easily recovered while preventing them from scattering around the wafer W.

[0101] Furthermore, conventionally, etching of wafers is performed by supplying an etching liquid, cleaning water, a first liquid, or a second liquid to the wafer and causing the etching liquid, cleaning water, the first liquid, and the second liquid to splash from the wafer. In this case, a large clean room of a size large enough for operators to perform work is used to accommodate the etching unit, cleaning unit, and mask layer removal unit.

[0102] On the other hand, in this embodiment, liquid is supplied to the wafer W and then sucked off the wafer W for recovery. Liquid that overflows from the wafer W and flows down through the gaps in the wafer support 3 is recovered by a bottle. Consequently, the device configurations of the etching unit 21, cleaning unit 31, and mask layer removal unit 41 can be significantly miniaturized. Consequently, these units 21, 31, 41, and the drying unit 51 can be housed in a glove box-type storage chamber 11, which is a compact ventilated chamber. This eliminates the need for a large clean room and significantly reduces the size and cost of the wet etching apparatus 1.

[0103] Furthermore, by using the glove box type storage chamber 11 , it is possible to effectively prevent the operator from inhaling vaporized etching liquid and dust generated during cleaning and drying after etching from adhering to the dried wafer W, similar to the case of using a clean room.

[0104] The wet etching apparatus 1 further includes a transport unit 61 within the storage chamber 11 for transporting the wafer support 3 supporting the wafer W. Thus, in this embodiment, the wafer support 3 supporting the wafer W can be easily transported between the etching unit 21, the cleaning unit 31, the mask layer removal unit 41, and the drying unit 51.

[0105] The wafer support 3, which supports the wafer W, comprises a main body 4 having a base 5 and a plurality of columns 6. The base 5 partially contacts the lower surface of the wafer W to place the wafer thereon, and the columns 6 are erected on the base 5 to surround the wafer W placed thereon. The main body 4 also comprises legs 8 extending outward from the main body 4. The use of the wafer support 3 allows liquid (such as cleaning water, first liquid, and second liquid) supplied to the wafer W placed on the base 5 of the wafer support 3 to flow out through gaps in the wafer support 3. This facilitates liquid recovery by pre-arranging a recovery container below the wafer support 3.

[0106] In the present embodiment, the etching unit 21 includes the etching liquid bottle 22. However, if the etching liquid recovery unit 26 can recover substantially all of the etching liquid, the etching liquid bottle 22 may not be used.

[0107] In this embodiment, the etching unit 21 includes the etching liquid recovery unit 26 for sucking the etching liquid. However, the etching unit 21 may not include the etching liquid recovery unit 26. In this case, the used etching liquid is recovered by the etching liquid bottle 22.

[0108] Furthermore, in this embodiment, the wet etching apparatus 1 includes an etching unit 21 and a cleaning unit 31 as separate units. This is not limiting, and for example, the etching unit 21 may further include a cleaning water supply unit 33. Specifically, etching can be performed while the wafer support 3 supporting the wafer W is engaged with the etching liquid bottle 22. After the etching liquid is recovered by the etching liquid recovery unit 26, the top surface of the wafer W is continuously cleaned by the cleaning water supply unit 33 without transporting the wafer support 3. In this case, the cleaning water flows to the etching liquid bottle 22, where it is accumulated and recovered. In this configuration, the cleaning liquid bottle 32 can be omitted, thereby achieving a more compact and cost-effective apparatus.

[0109] In this embodiment, the transport unit 61 includes the rotation unit 63, and the claw portion 62 is configured to be rotatable. However, the transport unit 61 may not include the rotation unit 63. In this case, the claw 62a of the claw portion 62 is preferably shaped so as to be easily hooked onto the leg 8 of the wafer support 3.

Claims

1. An etching device for wet etching a wafer supported by a wafer support, wherein: The etching device comprises: an etching unit that accumulates an etching liquid on an upper surface of a wafer supported by the wafer support to etch the upper surface of the wafer; a cleaning unit for cleaning an upper surface of a wafer supported by the wafer support member with cleaning water; a drying unit for rotating the wafer supported by the wafer support to dry the wafer; and a storage chamber for storing the etching unit, the cleaning unit, and the drying unit; The wafer support has a main body and legs, The main body includes: a base portion that partially contacts the lower surface of the wafer to place the wafer thereon; and A plurality of pillars are erected on the base so as to surround a wafer placed on the base. The legs extend outward from the main body. The cleaning unit is configured to recover the cleaning water flowing down from the gap of the wafer support. The etching device etches the upper surface of the wafer.

2. The etching apparatus according to claim 1, wherein The etching device also has a cleaning unit for maintaining the cleanliness of the storage chamber. The receiving chamber has an outlet for discharging gas from the receiving chamber and an inlet for allowing gas to enter the receiving chamber. The cleaning unit has: a pipe for allowing gas to flow from the outlet to the inlet; a fan, which is disposed on the pipe; a harm removal unit disposed in the pipe to remove toxic components from the gas; and The filter is disposed between the harm removal unit and the inlet in the pipe to remove dust contained in the gas.

3. The etching apparatus according to claim 1, wherein: The etching unit has: an etching liquid supply unit that drops a predetermined amount of etching liquid onto the upper surface of the wafer supported by the wafer support to form an etching liquid layer by utilizing surface tension; and An etching liquid recovery unit that draws the etching liquid from the upper surface of the wafer after etching. The cleaning unit has: a first bottle having an opening at an upper portion, the opening being larger than a diameter of the wafer and capable of engaging with the wafer support via the legs; and a cleaning water supply unit for supplying cleaning water to the upper surface of the wafer supported by the wafer support member engaged with the opening of the first bottle, The drying unit has: a holding table that holds the wafer support and suction-holds the lower surface of the wafer; and The rotating part rotates the holding table to dry the wafer.

4. The etching apparatus according to claim 3, wherein: The storage chamber is also provided with a mask layer removal unit for removing the mask layer formed on the upper surface of the wafer. The mask layer removal unit has: a second bottle having an opening at an upper portion, the opening being larger than a diameter of the wafer and capable of engaging with the wafer support member via the legs; a first liquid supplying portion for supplying the first liquid to the upper surface of the wafer supported by the wafer support engaged with the opening of the second bottle; and The second liquid supply unit supplies the second liquid to the upper surface of the wafer.

5. The etching apparatus according to claim 1, wherein The storage chamber is further provided with a transport unit for transporting the wafer support supporting the wafer. The transport unit has: claws that hook the legs of the wafer support to hold it; a horizontal movement unit that moves the claw in a horizontal direction; as well as A lifting unit lifts and lowers the claw.

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