JP3343503B2 - Cleaning equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus for cleaning a substrate which has been subjected to, for example, a film forming process or a polishing process.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process, it is necessary to maintain a high level of cleanliness on the surface of a semiconductor wafer (hereinafter referred to as "wafer") on which semiconductor devices are formed. Therefore, before and after each manufacturing process and processing process, the wafer surface is cleaned as necessary. For example, after the film forming process and the polishing process, the wafer surface is cleaned using a cleaning device shown in FIG. Has been done.

[0003] The cleaning device will be briefly described.
The apparatus holds the entire outer periphery of a wafer W and is rotatable in a horizontal direction by a rotation mechanism 12.
And a brush 1 contacting the upper surface of the wafer W with a predetermined pressure
3 and a cup 15 which surrounds the periphery of the wafer holding unit 11 and the wafer W and is vertically movable by an elevating mechanism 14. In such a cleaning apparatus, the wafer W is rotated in the horizontal direction, and the brush 1 is placed on the upper surface of the wafer.
The cleaning liquid is supplied via the nozzle 3 and the brush 13 is pressed against the upper surface of the wafer W to relatively slide the brush 13 with the wafer W, thereby removing particle contaminants on the upper surface of the wafer W.

[0004] In recent years, the following inconveniences have occurred, and there is an increasing demand for cleaning the back surface of a wafer. That is, if the exposure process is performed with the particles attached to the back surface, the particles are transferred to the stage for mounting the wafer, and the particles enter between the stage and the wafer. As a result, the wafers may be warped due to the particles that have entered, thereby causing the focus to collapse. If the annealing process is performed with the particles attached to the back surface, the particles enter from the back surface of the wafer during this process, and a current path is formed between the particles and the transistors on the front surface. It can happen.

For this reason, conventionally, the front and back surfaces of a wafer are cleaned by a cleaning apparatus shown in FIG. Here, in the cleaning apparatus of FIG. 8, since the entire outer periphery of the wafer W is held by the wafer holding unit 11 and there is no work area on the back surface side, the front surface and the back surface cannot be cleaned at the same time. For this reason, it is necessary to perform the front surface cleaning and the back surface cleaning separately. However, the pressing force of the brush 13 at the time of cleaning the front surface and the back surface of the wafer is different, and the problem of the throughput is caused by the problem of the throughput. In the cleaning device, the back surface cleaning unit 17 and the front surface cleaning unit 18 are separately provided.

In this cleaning apparatus, the wafer placed in the cassette chamber 16 with the front surface facing upward is first reversed by the reversing portion 19 so that the back surface faces upward.
In this state, the sheet is transported to the back surface cleaning unit 17 and the back surface is cleaned. Next, the surface is again turned upside down by the inversion unit 19, and the surface is washed by the surface washing unit 18. Here, the back surface is cleaned first because the cleaning solution on the surface being cleaned is spilled to the other surface side, and this cleaning solution may contaminate the other surface side. The back surface cleaning unit 17 and the front surface cleaning unit 18 have the same configuration as the cleaning device in FIG.

[0007]

However, in the above-described cleaning process, the back surface cleaning unit 17 and the front surface cleaning unit 18 are separately provided, and these cleaning units 17 and 18 are provided.
In addition, since the reversing unit 19 is required, there is a problem that the apparatus becomes considerably large. In addition, the number of processing steps is increased, such as cleaning the back surface after the wafer is inverted, and cleaning the front surface by reversing the wafer, so that the time required for the cleaning process becomes longer. Further, when one surface is cleaned, there is a problem that the cleaning liquid flows around the already cleaned other surface and particles adhere to the other surface.

The present invention has been made under such circumstances, and an object of the present invention is to provide a cleaning apparatus capable of reducing the size of the entire apparatus and reducing the processing time.

[0009]

For this reason, the cleaning apparatus of the present invention is provided at intervals along the contour of a circular substrate so as to be rotatable about a vertical axis, and the diameter increases as going downward.
An inclined surface portion which is circumferential face inclined to large, a plurality of rotation guide member for the substrate for the inclined surface by then <br/> holding an outer edge of the substrate and the guide so that the horizontal ,
A driving unit for driving and rotating at least one of the plurality of rotation guide members, and contacting the front and back surfaces of the substrate held by the rotation guide member, respectively, and moving on the substrate during rotation of the substrate Then, the first and second cleaning members for cleaning the front and back surfaces and the front and back surfaces of the substrate held by the rotation guide member are moved so as not to interfere with the first and second cleaning members. first and second cleaning liquid supply unit for supplying a respective cleaning liquid Te, with a width greater than the substrate
The substrate is placed on the upper surface of the narrow plate-shaped substrate transfer means, and
A substrate transfer means for holding a plate is surrounded by the rotation guide member.
The substrate by lowering it from above the
The substrate is delivered to a rotation guide member, and the substrate is rotated in the horizontal direction while the outer edge is sent out in a circumferential direction by an outer peripheral surface of the rotation guide member rotated by the driving unit, and guided by each rotation guide member. I do. Here, the horizontal in the present invention includes a substantially horizontal state. Ma
The first and second cleaning members are supported of the common support member
When the substrate is washed by cleaning, the substrate may move from one peripheral edge to the other peripheral edge.

[0010]

[0011]

[0012] In such a configuration, since the driving section for applying a rotational force to the rotation guide member is provided outside the rotation guide member, there are spaces on both sides of the substrate. For this reason, the first and second cleaning members can be provided on both sides of the substrate, whereby both surfaces of the substrate can be cleaned at the same time. Therefore, two cleaning units and a reversing unit are provided as in the related art. The entire device is smaller than the conventional device. Further, since both surfaces can be washed at the same time, the time required for the washing process is reduced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cleaning apparatus according to the present invention will be described below. FIG. 1 is a schematic perspective view of the cleaning apparatus, and FIG. 2 is a plan view. 2 in the figure (2a-2
Reference numeral e) denotes a rotation guide member, which is provided at intervals along a contour other than the notch (V-shaped cut) of the wafer W when the substrate, for example, the wafer W is at the cleaning position.

The rotation guide member 2 is provided with a rotation guide body 22 at the upper end of a rotation shaft 21. The rotation guide body 22 has a shape formed by combining a cylindrical body and a conical body as shown in FIGS. 1 and 5, and has an inclined surface portion 23 whose peripheral surface is inclined so that the diameter increases as going downward. are doing. The upper side of the inclined surface portion 23 is located outside the peripheral edge of the wafer W at the cleaning position (the holding position by the rotation guide member 2), and the lower side is located inside the peripheral edge of the wafer W. The peripheral portion of the wafer W is held by the surface portion 23 so that the wafer W is horizontal (including a substantially horizontal state).

For example, two of the rotary guide members 2a and 2c of the rotary guide member 2 have a drive unit 24 for rotating the rotary shaft 21 at the lower end of the rotary shaft 21, for example, a motor. And the remaining rotation guide member 2
The lower ends of the rotating shafts 21 of b, 2d and 2e are supported by bearings 25 as shown in FIG.

Thus, the rotation guide members 2a and 2c are
The rotation of the rotation guide member 24 causes the rotation guide members 2b, 2d, and 2e to rotate about the vertical axis. Then, by the rotation of the rotation guide member 2, the peripheral portion of the wafer W is sent out in the circumferential direction by the inclined surface 23 of the rotation guide body 22,
Thus, the wafer W is rotated in the horizontal direction while being guided by the rotation guide body 22.

The wafer W is transferred to the rotation guide member 2 by a transfer arm 3 (31, 32) serving as a substrate transfer means. The transfer arm 3 has a substantially rectangular shape narrower than the diameter of the wafer W as shown in FIGS. 3 and 4, for example, and a step portion 30 is formed on the upper surface thereof. The peripheral portion of the wafer W is placed on the upper surface of the step portion 30 to hold a part of the peripheral portion of the wafer W. Also, the first transport arm is used so that separate transport arms 3 are used before and after cleaning.
For example, two transport arms, that is, a transport arm 31 and a second transport arm 32, are provided vertically, for example.

The transport arm 3 is provided with a horizontal drive unit 33.
, And can be moved up and down by the vertical drive unit 34. As a result, the transfer arm 3 holds the peripheral portion of the wafer W, and in this example, enters between the rotation guide members 2c and 2d above the region surrounded by the rotation guide member 2, and descends from this position. Then, the wafer W is transferred to the rotation guide member 2.

As shown in FIGS. 1, 2, 5 and 6, a first surface for cleaning the surface of the wafer W is provided on the front side and the back side of the wafer W held by the rotation guide member 2. A first cleaning brush 41 as a cleaning member, and a second cleaning brush 42 as a second cleaning member for cleaning the back surface of the wafer W.

The first and second cleaning brushes 41, 4
Reference numeral 2 denotes a cylindrical sponge longer than the radius of the wafer W, as shown in FIGS. 1 and 2, for example, and a cleaning liquid described later is supplied from inside the brush. The cleaning brushes 41 and 42 are supported by a common support member 5 to clean the wafer W as shown in FIGS. 2 and 6 (a position indicated by a solid line in FIG. 2) and a standby position outside the wafer W. It is configured to move between a position (a position indicated by a chain line in FIG. 2). In the cleaning position, in this example, the base ends of the cleaning brushes 41 and 42 are located between the rotation guide members 2b and 2c, and the peripheral edge of the wafer W is positioned near the inside of the base end. Is done.

The support member 5 is provided with a pressure adjusting portion 51 as shown in FIG. 6, for example, and the pressure adjusting portion 51 has a horizontal base plate P1 and a base plate P2. The ends are each mounted as described below. First and second motors M1 and M2 are provided on the upper surfaces of the support plates P1 and P2, respectively, and the base end sides of the first and second cleaning brushes 41 and 42 are connected to these motors. It is attached to the terminals M1 and M2. Thereby, the cleaning brushes 41, 42
Is adapted to be rotated about a horizontal axis.

The pressure adjusting section 51 is, for example, shown in FIG.
A support 52 is provided as a representative of the support P1, and the base ends of the support plates P1 and P2 are attached to the front surface of the support 52 so as to be slidable up and down, respectively, and are horizontally fixed. A base end of the base 53 is attached, and support plates P1 and P2 are provided on the upper surface of the fixed base 53.
A pressurizing cylinder 54 for pressing the pressure from below is provided.

Each support plate P is provided on the back of the support post 52.
A weight 56 is suspended via a pulley 55 for each of the weights 1 and P2. The weights of the support plates P1 and P2 are balanced by the weights 56, and the support plate P1 is pressurized in that state. The cleaning brushes 41 and 42 are pressed by a cylinder 54, thereby adjusting the interval between the cleaning brushes 41 and 42 and adjusting the pressing force of the cleaning brushes 41 and 42 against the wafer W to a predetermined pressure.

Further, the supporting member 5 includes cleaning brushes 41 and 42.
Supply nozzles N1 and N2 for supplying a cleaning liquid to the x-direction drive unit 57 for moving the pressure adjustment unit 51 in the x-axis direction along the guide rail 57a.
And a θ-direction drive unit 58 for rotating the pressure adjustment unit 51 about the z-axis. Thus cleaning brush 4
1 and 42 are moved between the cleaning position and the standby position, and when cleaning the wafer W, the wafer W is moved in a horizontal direction from one peripheral portion of the wafer W to the central portion and to the other peripheral portion. Be moved. The cleaning brushes 41, 42
A brush cleaning mechanism (not shown) is provided at the standby position.

On the front side and back side of the wafer W held by the rotation guide member 2, as shown in FIGS. 1, 2 and 5, for supplying a cleaning liquid to the front side and back side of the wafer W. A first nozzle 61 serving as a first cleaning liquid supply unit and a second nozzle 62 serving as a second cleaning liquid supply unit wash the upper and lower sides of the first and second cleaning brushes 41 and 42, respectively. The brushes 41 and 42 are provided so as not to be buffered.

The nozzles 61 and 62 are supported by first and second support arms 63 and 64, respectively, and are provided at a supply position above the wafer (a position indicated by a solid line in FIG. 2) for supplying a cleaning liquid onto the wafer. ) And a standby position outside the wafer W (a position indicated by a dashed line in FIG. 2), and at the time of supplying the cleaning liquid onto the wafer, it moves substantially between the center of rotation and the peripheral edge of the wafer W. It is configured as follows. Here, as the cleaning liquid, for example, pure water is used in the cleaning after the film forming process, and in the cleaning after the polishing process, a chemical solution such as hydrofluoric acid and ammonia water is used. A plurality is prepared for each type.

Next, the operation of the above-described processing apparatus will be described. First, in a state where the first and second cleaning brushes 41 and 42 and the first and second nozzles 61 and 62 are located at the standby positions, the notch-aligned wafer W is transferred to, for example, the first transfer arm. The wafer W is transferred to the rotation guide member 2 as described above while being held by the
3 is held.

Next, the wafer W is rotated horizontally by the rotation guide member 2 as described above, while the cleaning brush 4 is rotated.
The support members 5 move the nozzles 1 and 42 to the cleaning position, and move the nozzles 61 and 62 to the supply position. At this time, the distance between the cleaning brushes 41 and 42 is set in advance by the pressure adjusting unit 51 so as to be larger than the thickness of the wafer W, and after moving to the cleaning position in this state,
The cleaning brushes 41 and 42 are respectively brought into contact with the front and back surfaces of the wafer W with a predetermined pressing force.

The cleaning liquid is supplied to the front surface and the back surface of the wafer W by the nozzles 61 and 62, respectively, and supplied through the cleaning brushes 41 and 42 by the supply nozzles N1 and N2. M1, M2
The cleaning process is performed while rotating by. At this time, the cleaning brushes 41 and 42 are moved by the support member 5 from one peripheral edge of the wafer W to the other peripheral edge, and the nozzles 61 and 42 are moved.
The cleaning process is performed by moving the wafer 62 between the rotation center of the wafer W and the peripheral edge so as not to interfere with the cleaning brushes 41 and 42.

In this way, the cleaning liquid supplied to the center of rotation of the wafer W flows while diffusing toward the peripheral edge by the centrifugal force of rotation, and spreads over the entire front and back surfaces of the wafer W. Then, while moving the cleaning brushes 41 and 42 longer than the radius of the wafer W, the cleaning brushes 41 and 4 are moved.
By sliding the wafer 2 and the wafer W, the wafer W is thoroughly washed from the center to the periphery. At this time, the cleaning wafer W is cleaned while being sandwiched between the two cleaning brushes 41 and 42 in a state where the pressing forces of the brushes 41 and 42 on the wafer W are adjusted to appropriate values. The front and back surfaces of the wafer W are cleaned to a predetermined degree of cleanliness.

After cleaning the wafer W in this manner, the nozzle 6
1, 62 to the standby position and the cleaning brush 4
1 and 42 are moved to the standby position after the interval between them is larger than the thickness of the wafer W. The wafer W is rotated at a high speed by the rotation of the rotation guide member 2, and the cleaning liquid is scattered and dried by the centrifugal force of the rotation, while the cleaning brushes 41 and 42 are provided at the standby position in parallel with the drying of the wafer W. The cleaning is performed by a cleaning mechanism (not shown). Next, the second transport arm 32 is moved to the rotation guide members 2c and 2d.
The wafer W is moved from the rotation guide member 2 to the transfer arm
The wafer W is transferred to the system 32 and transported to the next step after the cleaning. The drying step may be performed in a drying unit provided separately from the present apparatus.

In such a cleaning apparatus, the wafer is rotated by feeding the peripheral edge of the wafer in the circumferential direction while being held by the rotation guide member 2, so that the space can be formed on the back side of the wafer. For this reason, the cleaning brush 42 and the nozzle 62 for cleaning the back surface can be provided on the back surface side of the wafer, whereby the back surface as well as the front surface of the wafer can be cleaned at the same time. Therefore, since the front surface cleaning unit (back surface cleaning unit) and the reversing unit provided in the conventional apparatus are not required, the entire cleaning apparatus is significantly reduced in size as compared with the conventional apparatus. In addition, since the cleaning process for the front and back surfaces of the wafer can be performed at the same time, there is no need for a separate cleaning process, a reversing process, and a transfer to each process, which have been required in the past. Is improved.

Further, since the wafer itself rotates, the periphery of the wafer is evenly contacted with the cleaning brushes 41 and 42,
Moreover, since the wafer is cleaned while being sandwiched between the two cleaning brushes, it is difficult to use a conventional wafer holding portion that holds the entire outer periphery of the wafer and rotate the wafer together with the holding member. In addition, cleaning of the peripheral portion of the wafer and the end face of the wafer can be performed.

Further, since the washing liquid is scattered by the centrifugal force of rotation, it is possible to prevent the washing liquid from flowing to the other surface side, and even if the washing liquid is swirled, the other surface side is also washed. There is no possibility that the other side is contaminated by the cleaning liquid. The transfer arm 3 holds only a part of the peripheral edge of the wafer, has a small contact area with the wafer, and has separate transfer arms 3 before and after cleaning. Therefore, for example, when a single cleaning arm is used before and after cleaning, the particles transferred from the wafer to the transfer arm 3 by holding the wafer before cleaning can be used as the cleaning wafer. Can be prevented, and the contact area between the transfer arm 3 and the wafer is small.
Even if particles are attached to the transfer arm 3, the number of particles transferred from the transfer arm 3 to the wafer is reduced.

Next, another example of the present invention will be described with reference to FIG. Also in this example, the rotation guide member 7 (7a-
7e) is the rotating shaft 71 and the rotating guide body 7 as in the above-described example.
2, the rotation guide body 72 has an inclined surface portion whose peripheral surface is inclined so that the diameter is reduced most at a substantially central portion in the length direction, and the diameter is increased as going upward and downward from this position. And the peripheral edge of the wafer W is held at a position where the diameter of the inclined surface portion is the smallest.

The two rotation guide members 7a and 7c of the rotation guide member 7 are configured to be rotatable about a vertical axis by the driving unit 73, as in the above-described example, and are further horizontally moved. The direction drive unit 74 is configured to be able to move from the holding position of the wafer W to the outside of the contour of the wafer W. Thereby, these rotation guide members 7
a, 7c move outward to rotate guide members 7 adjacent to each other.
The wafer W is transported by the transfer arm 3 through the place where the distance between b and 7d is widened, and the remaining rotation guide members 7b, 7d,
7e, and thereafter, the rotation guide members 7a and 7c are moved to the holding position. Other configurations are the same as those in the above-described example.

In the above, in the present invention, a wafer on which an orientation flat (orientation flat) is formed can be used as the substrate. In this case, the rotation guide member 2 is arranged along the contour of the wafer other than the orientation flat. .
The adjustment of the pressing force of the cleaning brushes 41 and 42 on the wafer may be performed using a spring, or the nozzle 6 may be adjusted.
The reference numerals 1 and 62 do not have the pinpoint type as in the present embodiment, and may include a slit-like cleaning liquid supply unit.

Further, the transport arm 3 is provided, for example, for cooperating with a projecting pin (not shown) and the transport arm 3 so that the rotary guide member 2 is provided.
In this case, the projecting pins and the transfer arm 3 constitute a substrate transfer means. At this time, the transfer arm 3 changes the holding position of the wafer before and after cleaning with one transfer arm 3 instead of preparing two transfer arms 3 before and after cleaning. It may be configured as follows.

[0039]

According to the present invention, when cleaning the front and back surfaces of a substrate, it is possible to reduce the size of the entire cleaning apparatus and shorten the cleaning processing time.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing one embodiment of a cleaning device of the present invention.

FIG. 2 is a plan view showing the cleaning device.

FIG. 3 is a side view showing a transfer arm used in the cleaning device.

FIG. 4 is a plan view showing a transfer arm used in the cleaning device.

FIG. 5 is a side view showing a main part of the cleaning device.

FIG. 6 is a side view showing a support member provided in the cleaning device.

FIG. 7 is a schematic perspective view showing another example of the cleaning device of the present invention.

FIG. 8 is a side view showing a conventional cleaning device.

FIG. 9 is an explanatory view showing a conventional cleaning device.

[Explanation of symbols]

 Reference Signs List 2 rotation guide member 24 drive unit 3 transport arm 41 first cleaning brush 42 second cleaning brush 5 support member 51 pressure adjusting unit 61 first nozzle 62 second nozzle W semiconductor wafer

Continuation of front page (72) Inventor Keizo Hirose 650 Mitsuzawa, Hosaka-cho, Nirasaki-shi, Yamanashi Tokyo Electron Kyushu Co., Ltd. Process Development Center (56) References JP-A-9-69502 (JP, A) JP-A Heihei JP-A-1-105376 (JP, A) JP-A-60-143634 (JP, A) JP-A-1-184831 (JP, A) JP-A-8-241851 (JP, A) JP-A-1-179422 (JP, A) A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/304

Claims (2)

(57) [Claims] 1. A spaced along the rotatably circular board outline around each vertical axis, ho go down
It has an inclined surface part whose peripheral surface is inclined so that the throat diameter increases,
A plurality of rotation guide member for holding and guiding the outer edges of the substrate by the inclined surface portion so that the substrate is horizontal, for rotating to drive at least one of the plurality of rotating guide member And a first and second cleaning member that respectively contact the front and back surfaces of the substrate held by the rotation guide member, move on the substrate when the substrate rotates, and clean the front and back surfaces. A first and a second cleaning liquid supply unit that supplies a cleaning liquid by moving the front and back surfaces of the substrate held by the rotation guide member so as not to interfere with the first and second cleaning members, respectively; The substrate is placed on the upper surface of a plate-like substrate transfer means that is narrower than the substrate
And the substrate transfer means for holding the substrate
By lowering from above the area surrounded by the members,
The substrate is delivered to a rotation guide member, and the substrate is rotated in the horizontal direction while an outer edge is sent out in a circumferential direction by an outer peripheral surface of the rotation guide member rotated by the driving unit, and guided by each rotation guide member. A cleaning device characterized by the above-mentioned. 2. The cleaning device according to claim 1, wherein the first and second cleaning members move from one peripheral edge to the other peripheral edge of the substrate when the substrate is cleaned by being supported by a common support member. Item 7. The cleaning device according to Item 1.