JP7303689B2 - Etching equipment and wafer support - Google Patents

Description

The present invention relates to an etching apparatus and a wafer support.

Patent Documents 1 to 3 disclose wet etching. In wet etching, an etchant is supplied to the upper surface of a silicon wafer to etch the upper surface of the wafer.

JP-A-02-086130 JP-A-06-265869 JP 2017-028257 A

Conventionally, cleaning water for cleaning the wafer after etching is splashed around the wafer. Therefore, a large-sized waste liquid treatment apparatus is required in order to collect the splashed washing water.
SUMMARY OF THE INVENTION An object of the present invention is to suppress splashing of cleaning water during wet etching.

An etching apparatus (the present etching apparatus) of the present invention is a wet etching apparatus for wet-etching a wafer supported by a wafer support. An etching unit for etching the top surface, a cleaning unit for cleaning the top surface of the wafer supported by the wafer support with cleaning water, and a drying unit for spinning and drying the wafer supported by the wafer support. , an accommodation chamber for accommodating the etching unit, the cleaning unit, and the drying unit, the wafer support including a base part in partial contact with the lower surface of the wafer and on which the wafer is placed; and the base part. a main body portion including a plurality of pillars erected on the base portion so as to surround the wafer placed on the base; and legs protruding outward from the main body portion. It is configured to collect cleaning water flowing down from the gaps in the wafer support to etch the top surface of the wafer.

In addition, the present etching apparatus may further include a clean unit for maintaining cleanliness in the storage chamber, and the storage chamber includes an outlet for discharging gas from the storage chamber and an outlet for releasing gas from the storage chamber. The clean unit may comprise a pipe for flowing gas from the outlet to the inlet, a fan arranged in the pipe, a fan arranged in the pipe, and a toxic gas installed in the pipe. and a filter disposed between the abatement unit and the inlet in the pipe for removing dust contained in the gas.

Further, in this etching apparatus, the etching unit includes an etchant supply unit that drops a predetermined amount of etchant onto the upper surface of the wafer supported by the wafer support to form an etchant layer by surface tension; an etchant recovery part for sucking the etchant from the upper surface of the wafer after etching, the cleaning unit having an opening larger than the diameter of the wafer and capable of engaging the wafer support via the leg; a first bottle provided at the top; and a cleaning water supply unit for supplying 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 table that holds the wafer support and suction-holds the lower surface of the wafer, and a rotating part that spins the holding table to dry the wafer.

In this case, the etching apparatus may further include a mask layer removing unit that removes the mask layer formed on the upper surface of the wafer in the storage chamber, and the mask layer removing unit is larger than the diameter of the wafer. A second bottle having an opening at its top for engaging the wafer support via a leg; A first liquid supply section that supplies the first liquid and a second liquid supply section that supplies the second liquid to the upper surface of the wafer may be provided.

In addition, the etching apparatus may further include a transport unit for transporting the wafer support supporting the wafer in the housing chamber, and the transport unit includes claws for hooking and holding the legs of the wafer support. , horizontal movement means for moving the claws in the horizontal direction, and lifting means for lifting and lowering the claws.

In this etching apparatus, a wafer to be wet-etched is supported by a wafer support having a gap. The cleaning unit is configured to collect the cleaning water overflowing from the upper surface of the wafer and flowing down from the gap of the wafer support when the wafer supported by the wafer support is cleaned with the cleaning water. Therefore, in this etching apparatus, by arranging the collection container below the wafer support, it is possible to collect the cleaning water satisfactorily while suppressing scattering around the wafer.

In addition, as described above, this etching apparatus may include a clean unit for maintaining the cleanliness of the storage chamber. As a result, toxic substances and dust can be removed from the gas circulating in the storage chamber to maintain its cleanliness. Therefore, it is easy to maintain the cleanliness of the storage chamber.

Further, in this etching apparatus, as described above, the etching unit includes an etchant supply unit that forms an etchant layer on the upper surface of the wafer by surface tension, and an etchant recovery unit that absorbs the etchant from the upper surface of the wafer after etching. and may be provided.
In this configuration, etching is performed with the etchant accumulated on the upper surface of the wafer due to surface tension, so the amount of the etchant can be reduced. In addition, since the etchant is absorbed and recovered after etching, scattering of the etchant around the wafer can be suppressed. Note that the recovered etchant can be reused, although the etching time may become longer. Therefore, it is possible to reduce the frequency of using the waste liquid treatment apparatus for treating the etchant.

Further, in this etching apparatus, the cleaning unit includes, as described above, a first bottle having an opening capable of engaging the wafer support, and a cleaning water supply section for supplying cleaning water to the upper surface of the wafer. good too. With this configuration, it is possible to collect the cleaning water overflowing from the wafer and flowing down from the gap of the wafer support with the first bottle. Therefore, washing water can be easily recovered.

Furthermore, in this embodiment, the drying unit may comprise a holding table that holds the wafer support and the wafer, and a rotating part that spins the holding table, as described above. This allows the wafer to be easily dried.

Moreover, the wet etching apparatus may further include a mask layer removing unit in the storage chamber, as described above. This allows the mask to be easily removed from the wafer.
The mask layer removing unit also includes a second bottle having an upper opening similar to that of the first bottle, and a first liquid supply section and a second liquid supply section for supplying the first liquid and the second liquid to the upper surface of the wafer. and may be provided. In this configuration, it is possible to collect the first liquid, the second liquid, and the dissolved substance of the mask that flow down from the gap of the wafer support by the second bottle. Therefore, it is possible to easily collect the first liquid, the second liquid, and the dissolved material while suppressing scattering around the wafer.

Conventionally, the wafer is etched by supplying the etching liquid, the cleaning water, the first liquid, or the second liquid to the wafer, and scattering the etching liquid, the cleaning water, the first liquid, and the second liquid from the wafer. are doing. In this case, a large clean room is used to accommodate the etching unit, the cleaning unit and the mask layer removing unit, the size of which allows workers to work inside.

On the other hand, in this wet etching apparatus, the liquid is supplied to the wafer, and the liquid on the wafer is sucked up and collected, or the liquid flowing down from the gap of the wafer support is collected with a bottle. Therefore, the device structures of the etching unit, the cleaning unit and the mask layer removing unit can be significantly miniaturized. Therefore, these units and the drying unit can be accommodated in a compact accommodation chamber. This makes it possible to eliminate the need for a large clean room and significantly reduce the size and cost of the wet etching apparatus.

In addition, as described above, the wet etching apparatus may further include a transfer unit for transferring the wafer support inside the housing chamber. Thereby, the wafer support supporting the wafer can be easily transferred between the etching unit, the cleaning unit mask layer removing unit and the drying unit.

It is an explanatory view showing the configuration of a wet etching apparatus. It is a perspective view which shows a wafer support. FIG. 4 is a perspective view showing a wafer support on which a wafer is placed; FIG. 4 is an explanatory diagram showing the configuration of an etching unit; FIG. 4 is an explanatory diagram showing the structure of an etching liquid bottle; FIG. 4 is an explanatory diagram showing the configuration of a cleaning unit; FIG. 4 is an explanatory diagram showing the configuration of a mask layer removing unit; It is an explanatory view showing the composition of a drying unit. It is a perspective view which shows the structure of a drying unit. FIG. 4 is an explanatory diagram showing the configuration of a transport unit;

A wet etching apparatus 1 according to the present embodiment shown in FIG. 1 is an apparatus for wet etching a wafer W supported by a wafer support 3 . The wafer W to be wet-etched in this embodiment has, for example, a small diameter (for example, about 1 inch).

First, the configuration of the wafer support 3 will be described. As shown in FIGS. 2 and 3, the wafer support 3 has a main body 4 that supports the wafer W. As shown in FIGS. The body portion 4 includes a base portion 5 on which the wafer W is placed, a plurality of columnar portions 6 erected from the base portion 5, and a ring portion 7 provided so as to connect the upper ends of the columnar portions 6. .
The base portion 5 has a slightly larger diameter than the wafer W. The base portion 5 has a mesh shape having a frame portion (bone portion) 5a and holes 5b that are gaps between the frame portions 5a, and holds the wafer W while being in partial contact with the lower surface of the wafer W. do. The column portion 6 is erected on the outer peripheral portion of the base portion 5 so as to surround the wafer W placed on the base portion 5 .

Also, the wafer support 3 has a plurality of legs 8 projecting outward from the main body 4 . In this embodiment, six legs 8 protrude outward from the column portion 6 of the body portion 4 . Each leg 8 has a downwardly extending fastener 9 at its distal end.

Next, the configuration of the wet etching apparatus 1 will be described. As shown in FIG. 1, the wet etching apparatus 1 has an accommodation chamber 11 that serves as a housing for the wet etching apparatus 1 . The storage chamber 11 is a so-called glove box (small draft chamber), which is a sealed container designed so that only a hand can be put inside so that work can be performed in a state cut off from the outside air.

The accommodation chamber 11 accommodates an etching unit 21, a cleaning unit 31, a mask layer removal unit 41, and a drying unit 51 so as to be aligned along the longitudinal direction. Further, a transfer unit 61 for transferring the wafer support 3 supporting the wafer W is attached to the upper portion of the storage chamber 11 .
When the glove box is not used to put the hand into the housing chamber 11 , the wafer support 3 for supporting the wafer W is transferred by the transfer unit 61 .
A side wall of the housing chamber 11 has a loading port 101 for loading the wafer support 3 for supporting the wafer W into the housing chamber 11, a door 102 for opening and closing the loading port 101, and a door 102 for opening and closing. A door opening/closing means (air cylinder) 103 for opening and closing the door is provided.

The etching unit 21 shown in FIG. 4 etch the upper surface of the wafer W by storing an etchant on the upper surface of the wafer W supported by the wafer support 3 . As shown in FIG. 4, the etching unit 21 includes an etchant bottle 22 for mounting the wafer support 3, an etchant supply unit 23 for supplying the etchant, and a An etchant recovery unit 26 is provided.

The etchant bottle 22 has an opening 22a at the top, as shown in FIGS. The opening 22a is larger than the diameter of the wafer W and formed so as to be able to engage the wafer support 3 via the leg 8. As shown in FIG. That is, in the etching unit 21, as shown in FIG. 5, the wafer support 3 supporting the wafer W is engaged with the opening 22a of the etchant bottle 22 via the leg 8 having the fastener 9. be.

As shown in FIG. 4, the etchant supply unit 23 includes an etchant supply nozzle 24 for supplying the etchant, and an etchant supply nozzle elevating means 25 for vertically moving the etchant supply nozzle 24. I have. The etchant supply nozzle 24 can be communicated with the etchant supply source ES.

In the etchant supply section 23 , the etchant supply nozzle 24 is arranged at a predetermined height by the etchant supply nozzle elevating means 25 . The etchant supply nozzle 24 is connected to the etchant supply source ES, and a predetermined amount of etchant is dropped from the etchant supply nozzle 24 onto the upper surface of the wafer W supported by the wafer support 3 . Thereby, the etchant supply unit 23 forms the etchant layer EL on the upper surface of the wafer W by surface tension. Then, it waits for about 3 minutes from the formation of the etchant layer EL. As a result, the upper surface of the wafer W is etched (processed with a chemical solution).

As shown in FIG. 4, the etchant recovery unit 26 includes an etchant recovery nozzle 27 for recovering the etchant, and an etchant recovery nozzle elevating means 28 for vertically moving the etchant recovery nozzle 27. I have. The etchant collection nozzle 27 can be communicated with the suction source EV.

In the etchant recovery unit 26, the etchant recovery nozzle 27 is arranged at a height so as to come into contact with the etchant layer EL formed on the upper surface of the wafer W by the etchant recovery nozzle elevating means 28 after etching. Then, the etchant recovery nozzle 27 is communicated with the suction source EV to suck up the etchant forming the etchant layer EL from the upper surface of the wafer W. As shown in FIG. The etchant sucked up by the etchant recovery nozzle 27 is accumulated in an etchant recovery bottle (not shown) and recovered.

The etchant that has not been completely recovered by the etchant recovery unit 26 overflows from the upper surface of the wafer W, flows down through the gap of the wafer support 3 and falls into the etchant bottle 22 as indicated by the arrow A, and accumulates there. and recovered. The gaps of the wafer support 3 include, for example, between the plurality of pillars 6 and the holes 5b of the base 5 (see FIG. 2).

The etchant is, for example, a mixture of acetic acid, nitric acid and phosphoric acid. Also, the amount of the etchant forming the etchant layer EL is, for example, 0.3 mL. The recovered etchant is also approximately the same amount.

The cleaning unit 31 shown in FIG. 6 cleans the upper surface of the wafer W supported by the wafer support 3 with cleaning water. As shown in FIG. 6, the cleaning unit 31 includes a cleaning liquid bottle 32 on which the wafer support 3 is placed, and a cleaning water supply section 33 for supplying cleaning water.

The cleaning liquid bottle 32 has the same configuration as the etching liquid bottle 22 . That is, as shown in FIGS. 5 and 6, 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 formed so as to be able to engage the wafer support 3 via the leg 8. As shown in FIG. That is, in the cleaning unit 31, as shown in FIG. 5, the wafer supporter 3 supporting the wafer W is engaged with the opening 32a of the cleaning liquid bottle 32 via the legs 8 having the fasteners 9. . The cleaning liquid bottle 32 corresponds to an example of a first bottle.

As shown in FIG. 6, the cleaning water supply unit 33 includes a cleaning water supply nozzle 34 for supplying cleaning water and a cleaning water supply nozzle elevating means 35 for moving the cleaning water supply nozzle 34 in the vertical direction. I have. The cleaning water supply nozzle 34 can be communicated with the cleaning water supply source WS.

In the cleaning water supply unit 33 , the cleaning water supply nozzle 34 is arranged at a predetermined height by the cleaning water supply nozzle elevating means 35 . The cleaning water supply nozzle 34 is communicated with the cleaning water supply source, and the 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 (for example, pulse water supply). Thereby, the upper surface of the wafer W is cleaned with the cleaning water.

The cleaning water used for cleaning overflows the upper surface of the wafer W, flows down into the cleaning liquid bottle 32 through the gap of the wafer support 3, as indicated by the arrow B, and is accumulated and collected. In this manner, the cleaning unit 31 collects cleaning water flowing down from the gaps of the wafer support 3 .

A mask layer removing unit 41 shown in FIG. 7 removes a mask layer (not shown) made of resin formed on the upper surface of the wafer W. As shown in FIG. As shown in FIG. 7, the mask layer removing unit 41 includes a mask layer removing bottle 42 for mounting the wafer support 3, a first liquid supply section 43 for supplying a first liquid that is an organic solvent, It also has a second liquid supply section 46 for supplying a second liquid (mask removing liquid) which is another organic solvent.

The mask layer removing bottle 42 has the same configuration as the etchant bottle 22 . That is, as shown in FIGS. 5 and 7, the mask layer removing 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 the wafer support 3 via the leg 8. As shown in FIG. That is, in the mask layer removing unit 41, as shown in FIG. 5, the wafer supporter 3 supporting the wafer W is placed in the opening 42a of the mask layer removing bottle 42 via the legs 8 having the fasteners 9. engaged. The mask layer removing bottle 42 corresponds to an example of a second bottle.

As shown in FIG. 7, the first liquid supply unit 43 includes a first liquid supply nozzle 44 for supplying the first liquid and a first liquid supply nozzle for vertically moving the first liquid supply nozzle 44 . A nozzle lifting means 45 is provided. The first liquid supply nozzle 44 can be communicated with the first liquid supply source S1. The first liquid is an alcoholic liquid such as ethanol or isopropyl alcohol.

In the first liquid supply section 43 , the first liquid supply nozzle 44 is arranged at a predetermined height by the first liquid supply nozzle elevating means 45 . The first liquid supply nozzle 44 is communicated with the first liquid supply source S1, and the first liquid is supplied from the first liquid supply nozzle 44 onto the upper surface of the wafer W supported by the wafer support 3. As shown in FIG. As a result, moisture on the upper surface of the wafer W is replaced with the alcohol-based first liquid.

As shown in FIG. 7, the second liquid supply unit 46 includes a second liquid supply nozzle 47 for supplying the second liquid, and a second liquid supply nozzle 47 for vertically moving the second liquid supply nozzle 47 . A nozzle lifting means 48 is provided. The second liquid supply nozzle 47 can communicate with the second liquid supply source S2. The second liquid is, for example, acetone.

In the second liquid supply section 46 , the second liquid supply nozzle 47 is arranged at a predetermined height by the second liquid supply nozzle elevating means 48 . The second liquid supply nozzle 47 is communicated with the second liquid supply source S2, and the second liquid is supplied from the second liquid supply nozzle 47 onto the upper surface of the wafer W supported by the wafer support 3. As shown in FIG. As a result, the mask layer made of resin is dissolved and the mask layer is removed.

The first and second liquids supplied to the upper surface of the wafer W and the dissolved resin overflow from the upper surface of the wafer W, pass through the gaps of the wafer support 3, and reach the mask layer as indicated by the arrow C. It flows down into the removal bottle 42 for accumulation and collection. In this way, the mask layer removing unit 41 collects the first liquid, the second liquid and the dissolved resin that flow down from the gaps of the wafer support 3 .

The drying unit 51 shown in FIGS. 8 and 9 spins and dries the wafer W supported by the wafer support 3 . As shown in FIGS. 8 and 9, the drying unit 51 includes a holding table 53 that holds the wafer support 3 and a rotating part 57 that rotates the holding table 53 in the container 52 .

The holding table 53 holds the wafer support 3 that supports the wafer W and holds the lower surface of the wafer W by suction. The rotating part 57 spins the holding table 53 to dry the wafer W. As shown in FIG.

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

The bottom portion 54 has a larger diameter than the base portion 5 of the wafer support 3 . The support column pair 55 is formed from two support columns 55 a and is erected on the outer peripheral portion of the bottom surface portion 54 . The support column pair 55 is configured to hold the leg 8 of the wafer support 3 between two support columns 55a. Therefore, in this embodiment, six supporting column pairs 55 are erected on the base portion 5 so as to correspond to the six legs 8 of the wafer support 3 .

The holding surface 56 includes a porous ceramic material and communicates with a suction source (not shown) to suck the wafer W placed on the base portion 5 of the wafer support 3 through the base portion 5 . Hold.

The rotating portion 57 has a motor 59 inside a housing 58 . A spindle 59 a of the motor 59 is connected to the lower surface of the holding surface 56 of the holding table 53 . The wafer W is held on the holding surface 56 so that the rotating shaft of the motor 59 (the center of the spindle 59a) passes through the center of the wafer W, for example.

In the holding table 53, the holding table 53 holding the wafer support 3 is integrally rotated by the motor 59 of the rotating portion 57 (the rotation speed is, for example, 7500 rpm). As a result, the wafer W supported by the wafer support 3 and suction-held on the holding surface 56 of the holding table 53 is rotated around the center of the wafer W, for example. As a result, the liquid remaining on the upper surface of the wafer W (for example, the first liquid and the second liquid) is vaporized, and the upper surface of the wafer W is dried.

The transport unit 61 shown in FIG. 1 transports the wafer support 3 supporting the wafer W between the etching unit 21 , the cleaning unit 31 , the mask layer removing unit 41 and the drying unit 51 .

A rail R is arranged above each of the units 21, 31, 41, and 51 in parallel with the longitudinal direction of the storage chamber 11, which is the direction in which these units are arranged. The transport unit 61 is attached to the rail R so as to be movable along the rail R. As shown in FIG. Therefore, the transport unit 61 can reciprocate along the rail R above each unit 21 , 31 , 41 , 51 .

As shown in FIG. 10, the transfer unit 61 includes a claw portion 62 for holding the wafer support 3, a turning means 63 for turning the claw portion 62, an arm 64 for supporting the claw portion 62 and the turning means 63, an arm 64 , a lifting means 65 for vertically moving the turning means 63 and the claw portion 62, and a horizontal moving means 66 for horizontally moving the entire conveying unit 61 including the claw portion 62 along the rail R.

The claw portion 62 has a substantially U-shape and has a base portion 62b extending in the horizontal direction and two claws 62a extending downward from both ends of the base portion 62b. The claw portion 62 hooks and holds the leg 8 (see FIG. 2) of the wafer support 3 with the claw 62a.

The turning means 63 is attached to the base portion 62 b of the claw portion 62 . The turning means 63 turns around a rotation axis L extending in the vertical direction as indicated by an arrow La. As a result, the claw portion 62 (claw 62a) turns as indicated by the arrow Lb.

The arm 64 supports the swivel means 63 and the claw portion 62 with its tip. A lifting means 65 is attached to the base end of the arm 64 . The lifting means 65 is vertically moved within the horizontal moving means 66 by a drive mechanism (not shown) within the horizontal moving means 66 . As a result, the lifting means 65 can lift and lower the arm 64, the turning means 63 and the claw portion 62 as indicated by the double arrow U.

The horizontal movement means 66 holds the elevating means 65 inside. The horizontal movement means 66 horizontally moves along the rail R by a driving mechanism (not shown). Thereby, the horizontal movement means 66 can horizontally move the entire transport unit 61 including the claw portion 62 along the rail R as indicated by the double arrow T. As shown in FIG.

In the etching operation in the wet etching apparatus 1 , the transfer unit 61 or an operator places the wafer support 3 supporting the wafer W on the etchant bottle 22 of the etching unit 21 .

After etching, the transfer unit 61 moves horizontally above the etching unit 21, lowers the claw portion 62, and hooks the leg 8 of the wafer support 3 by the claw portion 62 (claw 62a). The conveying unit 61 raises the claw portion 62 holding the wafer support 3 , moves horizontally above the cleaning unit 31 , lowers the claw portion 62 , and transfers the wafer support 3 to the cleaning liquid bottle 32 . Place. In this manner, the cleaning unit 31 transports the wafer support 3 between the units 21, 31, 41, and 51. FIG.

In addition, as shown in FIG. 1, the storage chamber 11 has an outlet 12 for letting out gas in the storage chamber 11 and an inlet 13 for introducing gas into the storage chamber 11 .
The outlet 12 is provided below the sidewall near the drying unit 51 in the accommodation chamber 11 . The inlet 13 is formed in the upper part of the storage chamber 11 along the longitudinal direction of the storage chamber 11, for example, in the shape of a groove.

The wet etching apparatus 1 further includes a clean unit 71 for maintaining cleanliness within the storage chamber 11 . This clean unit 71 has a pipe 72 . A pipe 72 connects the outlet 12 and the inlet 13 and is used to flow gas from the outlet 12 toward the inlet 13 . The clean unit 71 further includes a fan 73 , an abatement unit 74 and a dust filter (filter) 75 arranged in the pipe 72 .
Fan 73 creates a flow of gas in pipe 72 from outlet 12 to inlet 13 .

The abatement unit 74 removes toxic components from the gas within the pipe 72 . The abatement unit 74 includes a housing 81 that takes in and discharges the gas in the pipe 72, as shown in FIG. Furthermore, the abatement unit 74 is provided with a water supply device 82 communicating with an external water source 83, an abatement filter 85, and an outlet port 84 for discharging the water supplied from the water supply device 82 in the housing 81. ing.

The abatement unit 74 having such a configuration removes toxic components from the gas taken in from the pipe 72 by water supplied from the water supply device 82, water droplets WL, and the abatement 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 indicated by the arrow D.

The gas from which toxic components have been removed passes through a dust filter 75 arranged between the abatement unit 74 and the inlet 13 via a fan 73 . The dust filter 75 removes dust contained in gas from the gas passing through itself. The gas that has passed through the dustproof filter 75 is returned into the housing chamber 11 through the inlet 13 .

As described above, in this embodiment, the wafer W to be wet-etched is supported by the wafer support 3 having gaps (between the columns 6 and the hole 5b of the base 5, etc.; see FIG. 2). ing.

The cleaning unit 31 is configured to collect the cleaning water overflowing from the upper surface of the wafer W and flowing down from the gap of the wafer support 3 when cleaning the wafer W supported by the wafer support 3 with the cleaning water. there is Therefore, in the present embodiment, by arranging the collection container (cleaning liquid bottle 32) below the wafer support 3, the cleaning water can be recovered well while preventing the cleaning water from scattering around the wafer W. can do.

In addition, in this embodiment, the wet etching apparatus 1 includes a clean unit 71 for maintaining cleanliness in the storage chamber 11 . As a result, toxic substances and dust can be removed from the gas circulating in the storage chamber 11 to maintain its cleanliness, so that the cleanliness of the storage chamber 11 can be easily maintained.

Further, in this embodiment, the etching unit 21 includes an etchant supply unit 23 for forming an etchant layer on the upper surface of the wafer W supported by the wafer support 3 by surface tension, and an etching solution supply unit 23 for etching from the upper surface of the wafer W after etching. and an etchant recovery unit 26 that absorbs the liquid.

As described above, in the present embodiment, etching is performed with the etchant accumulated on the upper surface of the wafer W due to surface tension, so the amount of the etchant can be reduced. In addition, since the etchant is absorbed and recovered after etching, scattering of the etchant around the wafer W can be suppressed. Note that the recovered etchant can be reused, although the etching time may become longer. Therefore, it is possible to reduce the frequency of using the waste liquid treatment apparatus for treating the etchant.

Further, in this embodiment, the cleaning unit 31 includes a cleaning liquid bottle 32 having an opening 32a at the top. The cleaning unit 31 further includes a cleaning water supply section 33 that supplies cleaning water to the upper surface of the wafer W supported by the wafer support 3 engaged with the opening 32 a of the cleaning liquid bottle 32 .

By engaging the leg 8 of the wafer support 3 with the opening 32 a of the cleaning liquid bottle 32 , the wafer W can be placed in the center of the opening 32 a of the cleaning liquid bottle 32 . That is, the wafer W can be arranged in the center of the opening 32a as if it is floating in the air.
Therefore, in the cleaning unit 31 , the cleaning liquid overflowing from the wafer W and flowing down from the gap of the wafer support 3 can be recovered by the cleaning liquid bottle 32 . Therefore, washing water can be easily recovered.

Furthermore, in this embodiment, the drying unit 51 includes a holding table 53 that holds the wafer support 3 and sucks and holds the lower surface of the wafer W, and a rotating part 57 that spins the holding table 53 to dry the wafer W. It has Thereby, the wafer W can be easily dried. In particular, in this embodiment, the support column pair 55 of the holding table 53 sandwiches the leg 8 of the wafer support 3 . Therefore, it is possible to easily prevent the wafer W from dropping from the holding table 53 due to centrifugal force during spin rotation.

In this embodiment, the wet etching apparatus 1 further includes a mask layer removing unit 41 for removing a mask layer made of resin and formed on the upper surface of the wafer W in the storage chamber 11 . The mask layer removing unit 41 includes a mask layer removing bottle 42 having an opening 42a at the top. Further, the mask layer removing unit 41 includes a first liquid supply section 43 that supplies the first liquid to the upper surface of the wafer W supported by the wafer support 3 engaged with the opening 42 a of the mask layer removing bottle 42 . , and a second liquid supply unit 46 for supplying the second liquid to the upper surface of the wafer W.

Therefore, in the mask layer removing unit 41 , the mask layer removing bottle 42 can recover the first liquid, the second liquid, and the dissolved resin overflowing from the wafer W and flowing down from the gap of the wafer support 3 . Therefore, the first liquid, the second liquid, and the dissolved resin can be easily collected while preventing the first liquid, the second liquid, and the dissolved resin from scattering around the wafer W.

Conventionally, the wafer is etched by supplying the etching liquid, the cleaning water, the first liquid, or the second liquid to the wafer, and scattering the etching liquid, the cleaning water, the first liquid, and the second liquid from the wafer. are doing. In this case, a large clean room is used to accommodate the etching unit, the cleaning unit and the mask layer removing unit, the size of which allows workers to work inside.

On the other hand, in the present embodiment, the liquid is supplied to the wafer W, and the liquid on the wafer W is sucked up and recovered, or the liquid overflowing from the wafer W and flowing down from the gap of the wafer support 3 is recovered by a bottle. there is Therefore, the device structures of the etching unit 21, the cleaning unit 31 and the mask layer removing unit 41 can be significantly reduced in size. Therefore, these units 21, 31, 41 and the drying unit 51 can be accommodated in the glove box type accommodation chamber 11 which is a small draft. This makes it possible to eliminate the need for a large clean room and significantly reduce the size and cost of the wet etching apparatus 1 .

In addition, the use of the glove box type storage chamber 11 prevents the operator from inhaling the vaporized etchant, and the dust generated when cleaning and drying are performed after etching. can be well suppressed as in the case of using a clean room.

The wet etching apparatus 1 further includes a transfer unit 61 for transferring the wafer support 3 supporting the wafer W inside the storage chamber 11 . Thereby, in this embodiment, the wafer support 3 supporting the wafer W can be easily transferred between the etching unit 21 , the cleaning unit 31 , the mask layer removing unit 41 and the drying unit 51 .

The wafer support 3 for supporting the wafer W includes a base portion 5 on which the wafer W is placed while partially contacting the lower surface of the wafer W, and a base portion 5 surrounding the wafer W placed on the base portion 5 . A main body part 4 including a plurality of pillars 6 erected on the body part 4 and legs 8 projecting outward from the main body part 4 are provided. By using the wafer supporter 3 , the liquid (cleaning water, first liquid, second liquid, etc.) supplied to the wafer W placed on the base portion 5 of the wafer supporter 3 can be discharged into the gap of the wafer supporter 3 . can be spilled from Thus, by arranging the recovery container below the wafer support 3, the liquid can be easily recovered.

In addition, in this embodiment, the etching unit 21 is provided with the etchant bottle 22 . In this regard, if substantially all of the etchant can be recovered by the etchant recovery unit 26, the etchant bottle 22 may not be used.

Further, in this embodiment, the etching unit 21 is provided with an etchant recovery section 26 that absorbs the etchant. However, the etching unit 21 does not have to include the etchant recovery section 26 . In this case, the used etchant is collected by the etchant bottle 22 .

Further, in this embodiment, the wet etching apparatus 1 includes the etching unit 21 and the cleaning unit 31 as separate units. Not limited to this, for example, the etching unit 21 may further include the cleaning water supply section 33 . That is, etching is performed in a state in which the wafer support 3 supporting the wafer W is engaged with the etchant bottle 22, and after the etchant is recovered by the etchant recovery unit 26, the wafer support 3 is The upper surface of the wafer W may be washed continuously by the washing water supply unit 33 without transporting the wafer W. In this case, the cleaning water flows down into the etchant bottle 22 and is accumulated and collected. With this configuration, the cleaning liquid bottle 32 can be omitted, so that the size and cost of the apparatus can be reduced.

Further, in the present embodiment, the transport unit 61 is provided with a rotating means 63, and the claw portion 62 is configured to be able to rotate. However, the transport unit 61 does not have to be equipped with the turning means 63 . In this case, it is preferable that the shape of the claw 62a of the claw portion 62 is such that the leg 8 of the wafer support 3 can be easily hooked.

1: Wet etching equipment,
3: Wafer support, 4: Body portion, 5: Base portion, 6: Column portion, 8: Feet,
11: containment room, 12: exit, 13: entrance,
21: Etching unit, 22: Etching solution bottle, 22a: Opening,
23: etchant supply unit, 24: etchant supply nozzle,
25: etchant supply nozzle elevating means, 26: etchant recovery unit,
27: etchant recovery nozzle, 28: etchant recovery nozzle elevating means,
31: washing unit, 32: washing liquid bottle, 32a: opening,
33: washing water supply unit, 34: washing water supply nozzle,
35: cleaning water supply nozzle elevating means, 41: mask layer removing unit,
42: bottle for mask layer removal, 42a: opening,
43: first liquid supply section, 44: first liquid supply nozzle, 45: first liquid supply nozzle lifting means 46: second liquid supply section, 47: second liquid supply nozzle, 48: second liquid supply nozzle lifting means 51: drying unit, 53: holding table, 54: bottom part,
55: support column pair, 56: holding surface, 57: rotating part, 59: motor,
61: transport unit, 62: claw portion, 63: turning means, 64: arm,
65: lifting means, 66: horizontal moving means,
71: clean unit, 72: piping, 73: fan, 75: dust filter,
74: abatement unit,
82: water supply device, 83: water source, 84: discharge port, 85: detoxification filter

Claims (5)

A wet etching apparatus for wet etching a wafer supported by a wafer support,
an etching unit for etching the upper surface of the wafer by storing an etchant on the upper surface of the wafer supported by the wafer support;
a cleaning unit for cleaning the upper surface of the wafer supported by the wafer support with cleaning water;
a drying unit for spinning and drying the wafer supported by the wafer support;
an accommodation chamber that accommodates the etching unit, the cleaning unit, and the drying unit;
The wafer support includes:
a base portion on which the wafer is placed in partial contact with the lower surface of the wafer;
a leg projecting outward from the main body,
The cleaning unit is configured to collect cleaning water flowing down from gaps in the wafer support.
An etching device that etches the top surface of a wafer. further comprising a clean unit for maintaining cleanliness in the containment chamber;
The storage chamber has an outlet for letting gas out of the storage chamber and an inlet for putting gas in the storage chamber,
The clean unit is
piping for flowing gas from the outlet to the inlet;
a fan disposed in the pipe;
a harm removal unit disposed in the pipe for removing toxic components of the gas;
a filter disposed between the abatement unit and the inlet in the pipe for removing dust contained in the gas;
The etching apparatus according to claim 1. The etching unit comprises
An etchant supply unit that drops a predetermined amount of etchant onto the upper surface of the wafer supported by the wafer support to form an etchant layer by surface tension, and absorbs the etchant from the upper surface of the wafer after etching. and an etchant recovery unit,
The washing unit
A first bottle having an opening larger than the diameter of the wafer and capable of engaging the wafer support through the leg, and the wafer support engaged with the opening of the first bottle. a cleaning water supply unit that supplies cleaning water to the upper surface of the wafer;
The drying unit comprises
A holding table that holds the wafer support and sucks and holds the lower surface of the wafer, and a rotating part that spins and rotates the holding table to dry the wafer,
The etching apparatus according to claim 1. further comprising a mask layer removing unit for removing a mask layer formed on the upper surface of the wafer in the storage chamber;
The mask layer removing unit comprises:
a second bottle having an opening at the top larger than the diameter of the wafer and capable of engaging the wafer support via the foot;
on the upper surface of the wafer supported by the wafer support engaged with the opening of the second bottle;
a first liquid supply unit that supplies the first liquid;
a second liquid supply unit that supplies the second liquid to the upper surface of the wafer;
4. The etching apparatus according to claim 3. further comprising a transport unit for transporting the wafer support that supports the wafer in the storage chamber;
The transport unit is
a claw for hooking and holding the leg of the wafer support;
horizontal movement means for horizontally moving the claw;
and elevating means for elevating the claw,
The etching apparatus according to claim 1.

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