JPH0974078A - Cleaner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the treatment efficiency and improve the yield by cleaning a substance to be treated, in stably preserved condition, and bringing the substance to be treated and treatment liquid into contact with each other. SOLUTION: A wafer boat 30, which retains a plurality of wafers W in condition that they are soaked in treatment liquid, being erected in parallel within a treatment vessel 15A is composed of first and second retaining rods 32 and 33, which retain the bottoms on both sides of the wafers W each, and third and forth retaining rods 34 and 35 which retain the vicinities on both sides of the orientation flats Wo provided at the wafers W. Retaining grooves 32a and 33a to support the weight of the wafer W are arranged in longitudinal direction at the first and second retaining rods 32 and 33, and for the third and fourth retaining rods 34 and 35, retaining grooves 34a and 35a to prevent the fall of the wafers W are arranged in longitudinal direction. Hereby, a plurality of wafers can be retained in stable condition at specified intervals, and the contact between the wafer W and the treatment liquid can be uniformized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus.

[0002]

2. Description of the Related Art Conventionally, in a semiconductor manufacturing process, particles such as particles, organic contaminants, metal impurities, etc. adhering to the surface of a semiconductor wafer (hereinafter referred to as a wafer) which is an object to be processed are contaminated or naturally formed on the surface. A cleaning processing apparatus is used to remove an oxide film and the like.
This type of cleaning processing apparatus, for example, a wafer with ammonia,
The surface of a wafer is cleaned by successively immersing it in a processing solution such as an alkaline chemical solution such as hydrofluoric acid or an acidic chemical solution, and pure water. For example, a processing tank containing each processing solution arranged linearly and a loader Wafer transfer device having a wafer chuck as a transfer / holding means for holding and processing unprocessed wafers carried into the processing section and sequentially transferring them to the processing tank; and a processing tank for holding the wafer transferred by the wafer chuck and processing the wafers. The wafer boat is a holding means for holding the wafer in a state of being immersed therein.

In the cleaning apparatus having the above-mentioned structure, the wafer boat has a structure as shown in FIG.
Three rod-shaped holding members b, c, d are constructed between a pair of support plates a provided so as to face each other. Of these, the left and right holding members b and c hold lower portions on both sides of the wafer W, and the holding member d holds the lower end of the wafer W, and the upper surface thereof holds the holding members b and c.
holding grooves e, f, which are cut over the entire width of c, d,
A large number of g's are arranged in parallel with the longitudinal direction to form a comb-tooth shape. Of these, the holding grooves e and f provided in the holding members b and c support the weight of the wafer W, and the holding groove g provided in the holding member d is configured to prevent the wafer W from falling over. ing.

Using the wafer boat constructed as described above, a plurality of wafers W, for example, 50 wafers W are vertically erected and held at intervals, and a processing solution such as a chemical solution or pure water is introduced into the processing tank from below, for example. The wafer W is supplied, and the wafer W is immersed in the treatment liquid, and an appropriate cleaning treatment such as etching with a chemical solution or rinsing treatment with pure water is performed. The processed wafer W is pulled up by the wafer chuck and transferred to the processing step of the next step, or is lifted together with the wafer boat and transferred to the processing step of the next step.

[0005]

By the way, the wafer W is provided with a flat orientation flat Wo on a part of its outer circumference in order to facilitate discrimination and alignment of the crystal direction and conduction type, and this orientation flat Wo. May want to be located below during the cleaning process. However, in the conventional cleaning processing apparatus, as described above, the three holding members a, b,
Since the wafer W is held at c, the orientation flat W
When o is located below, the wafer W is not sufficiently held in the holding groove f of the holding member d as shown in FIG.
However, there is a problem in that the cleaning process is hindered by the contact with.

Further, the three holding members b, c, d need to have strength in order to hold, for example, 50 wafers W. For that purpose, the diameters and widths of the holding members b, c, d are set. It has to be big. In particular, when the holding members b, c, d are formed of synthetic resin members, the width needs to be wide. Therefore, the contact portions between the holding members b, c, d and the wafer W increase, and particles are likely to be generated due to the contact. Further, when the contact area between the holding members b, c, d and the wafer W increases, in the vicinity of the holding portion of the wafer W,
As shown in FIG. 6A, there is also a problem that stagnation of the processing liquid occurs, uniform contact between the processing liquid and the wafer W cannot be obtained, and the processing capacity is lowered. Further, the wafer W and the holding grooves e, f,
Since the flow of the processing liquid between the wafer boat and the wafer g becomes worse, the holding groove e,
The liquid droplets are likely to be accumulated in f and g, and the liquid droplets may adhere to the wafer W and be conveyed to the next process. As a result, the particles are likely to adhere to the wafer W after the rinse processing. There is also a problem that the yield is reduced.

The present invention has been made in view of the above circumstances. The object to be processed is washed while being stably held, and the object to be processed and the processing liquid are brought into uniform contact with each other to improve the processing efficiency and the yield. It is an object of the present invention to provide a cleaning processing device that can be designed.

[0008]

In order to achieve the above object, the first cleaning treatment apparatus of the present invention comprises a treatment tank for containing a treatment liquid for dipping the object to be treated, and a plurality of treatment tanks in the treatment tank. On the premise of a cleaning processing apparatus comprising: a holding means for holding the objects to be processed in parallel standing in a state of being immersed in the processing liquid, the holding means holds the lower parts on both sides of the objects to be processed. The first and second holding rods, and the third and fourth holding rods that are located below the first and second holding rods and hold both sides of the lower end of the object to be processed, respectively. The first and second holding rods are provided with holding grooves for supporting the weight of the object to be processed in a row in the longitudinal direction, and the third and fourth holding rods prevent the object to be fallen. The holding grooves are arranged in a row in the longitudinal direction (Claim 1).

A second cleaning processing apparatus of the present invention is a state in which a processing bath for containing a processing liquid for dipping a wafer and a plurality of the above-mentioned wafers are set up in parallel in the processing bath and immersed in the processing liquid. On the premise of a cleaning apparatus including a holding means for holding the wafer, the holding means includes first and second holding rods for holding lower portions of both sides of the wafer, and both sides of an orientation flat provided on the wafer. And holding grooves for supporting the weight of the wafer are arranged in a row in the longitudinal direction, and the third and fourth holding bars for holding the weight of the wafer are provided in the third and fourth holding bars. The holding bar is characterized in that holding grooves for preventing the wafer from falling are arranged in a row in the longitudinal direction (claim 2). In this case, the distance between the third holding rod and the fourth holding rod is preferably longer than the length of the orientation flat portion of the wafer (claim 3).

In the present invention, each of the first to fourth holding rods has a rod-shaped base portion, and a plurality of holding members provided so as to project upward from the upper surface of the base portion so that the width is narrower than the width of the base portion. Composed of comb-shaped grooves in which the grooves are arranged in parallel in the longitudinal direction, the base portion forms a neck portion extending downward from the groove portion and a shoulder portion inclined downward from the neck portion, and the bottom surface is It is preferable that it is formed to be convex downward (claim 4).

According to the cleaning processing apparatus of the present invention configured as described above, the holding means includes the first and second holding rods for holding the lower portions on both sides of the processing target (wafer), respectively, and the processing target. A holding groove for supporting the weight of the object to be processed (wafer) is formed on the first and second holding rods, the holding groove being formed of a third holding rod and a fourth holding rod that hold both sides of the lower end of the wafer. The third and fourth holding rods are provided with holding grooves for preventing the to-be-processed object (wafer) from tipping over in the longitudinal direction, so that the to-be-processed object regardless of the position of the orientation flat or the like. The (wafer) can be held in a stable state and can be immersed in the processing liquid (claims 1, 2, and 3).

The first to fourth holding rods each have a rod-shaped base portion and a plurality of holding grooves extending upward from the upper surface of the base portion so that the width of the base portion is narrower than the width of the base portion. It is composed of comb-teeth-shaped grooves arranged in parallel in the direction, and a neck portion extending downward from the groove portion and a shoulder portion inclined downward from the neck portion are formed on the base portion,
By forming the bottom surface in a convex shape downward, it is possible to reduce the overlapping portion of the object to be processed (wafer) and the holding rod as much as possible, and suppress the pooling of the processing solution due to stagnation. In addition to being possible, the contact between the processing liquid and the object to be processed (wafer) can be made uniform (claim 4).

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings. Here, a case where the cleaning processing apparatus of the present invention is applied to a semiconductor wafer cleaning apparatus will be described.

As shown in FIG. 1, the semiconductor wafer cleaning apparatus is carried by a carry-in section 1 for accommodating an unprocessed semiconductor wafer W (hereinafter referred to as a wafer) and a wafer carrying apparatus 2. A cleaning processing unit 3 that performs a cleaning process such as a chemical solution process and a water cleaning process on the wafer W, and a carry-out unit 4 that stores the cleaned wafer W are the main components.

The carrying-in section 1 is a waiting section 6 for a carrier C for accommodating the wafer W, a loader section 5 for taking out the wafer W from the carrier C, aligning the orientation flat, and detecting the single wafer of the wafer W, and the like. The carrier transport arm 7 is provided for transporting the carrier C to the standby unit 6 and transporting the carrier C between the standby unit 6 and the loader unit 5.

A carrier cleaning / drying line 8 for cleaning and drying the empty carrier C after the wafer W is taken out by the wafer transfer device 2 is provided above the cleaning processing unit 3 above. Are arranged along. The carrier cleaning / drying line 8 has a lifting mechanism 9
The empty carrier C is configured to be lifted from the loader unit 5 and supplied via the. A similar lifting mechanism (not shown) is also provided on the unloading unit 4 side, and the carrier C after cleaning and drying is supplied to the unloading unit 4 via this lifting mechanism. A treatment liquid tank / pipe region 10 including a tank and a pipe group (not shown) for containing a treatment liquid such as a chemical liquid is provided on the back side of the cleaning treatment unit 3.

On the other hand, the cleaning processing section 3 includes the wafer transfer device 2, a chuck cleaning / drying processing tank 11 for cleaning and drying the wafer chuck 20 of the wafer transfer device 2, and the chuck cleaning / drying processing tank 11. A first chemical cleaning device 12a, which is sequentially disposed on the downstream side and processes unnecessary substances such as organic contaminants, metal impurities or particles on the surface of the wafer W by cleaning, and the wafer W after the chemical processing is rinsed with water 2
Second first and second water washing / cleaning devices 13a, 13b, second chemical liquid treatment different from the first chemical liquid washing device 12a
Chemical cleaning device 12b, two third and fourth water cleaning devices 13c and 13d, a chuck cleaning / drying treatment tank 11 for cleaning and drying the wafer chuck 20, and a wafer W from which impurities have been removed, for example, isopropyl. Alcohol (I
And a drying treatment tank 14 for performing steam drying with PA) or the like. Then, the first and second chemical cleaning devices 12a,
12b and 1st thru | or 4th washing washing | cleaning apparatus 13a-13
In the case of d, the washing treatment liquid overflows, and the overflowing washing treatment liquid is discharged in the case of water washing treatment, and the overflowing washing treatment liquid is circulated in the case of chemical treatment to remove accumulated impurities. A processing tank 15 that is circulated (specifically, a chemical solution processing tank and a rinse processing tank are provided) is provided.

The wafer transfer device 2 is a wafer chuck 20 which is a holding means for holding, for example, 50 wafers W at a time, and the wafer chuck 20 in the horizontal direction (X,
A drive mechanism 21 for moving in the Y direction) and an ascending / descending direction (Z direction), and a transport path 2 arranged along the plurality of processing tanks 15.
2 and are configured to reciprocate along the transport path 22. The wafer chuck 20 and the drive mechanism 2
A bellows 23 for preventing the particles generated inside from scattering to the outside is attached between the bellows 23 and 1.

As shown in FIG. 2, the wafer chuck 20 has two rotating arms 24 that horizontally project from the main body of the wafer transfer device 2 and can rotate in the horizontal direction, and the two lower ends of the rotating arms 24. Two brackets 25 projecting toward each other and a plurality of holding grooves 26a, 2 which are provided between the brackets 25, 25 and hold the wafer W.
Two holding rods 26A in which 6b are arranged in rows at appropriate intervals,
26B, and is configured so that the edge portions of the wafer W can be held in the holding grooves when the rotating arms 24, 24 move toward and away from each other by the driving of the driving mechanism 21. In this case, the holding groove 26a of the holding bar 26A on the upper side is formed to have a substantially Y-shaped cross section to prevent the wafer W from collapsing. Further, the holding groove 26b of the holding bar 26B on the lower side is formed in a substantially V-shaped cross section so that the weight of the wafer W can be supported.

On the other hand, a wafer boat 30 for holding the wafer W is arranged in the processing tank 15 for containing the processing liquid (see FIGS. 3 and 4). This wafer boat 30
Are a pair of inverted T-shaped support members 31 arranged along opposite side walls of the processing tank 15, and are installed on both sides of the lower parts of the support members 31 to hold the lower parts of both sides of the wafer W. Third and fourth holding rods 34, which are located at the lower end sides of the first and second holding rods 32 and 33 and the supporting member 31, and are arranged to hold both sides of the orientation flat Wo of the wafer W,
And 35. The first to fourth holding rods 32 to 35 each have a rod-shaped base portion 40 and a plurality of holding grooves provided so as to project upward from the upper surface of the base portion 40 so that the width of the base portion 40 is narrower than the width of the base portion 40. 32
a, 33a, 34a, and 35a are arranged in parallel in the longitudinal direction, and a comb-tooth-shaped groove portion 41 is formed.

A neck portion 42 extending downward from the groove portion 41 and a shoulder portion 43 inclined downward from the neck portion 42 are formed in the base portion, and a bottom surface 44 is formed in a convex shape downward. (See FIG. 5A). By forming in this way, it is possible to suppress the liquid pool due to the stagnation of the processing liquid. In this case, the convex shape of the lower surface 44 is triangular, but it may be streamlined. The support member 31 and the holding rods 32 to 35 configured in this way are
For example, it is formed of a quartz member or a synthetic resin member such as PEEK (polyether / ether / ketone).

In this case, of the holding grooves 32a to 35a,
Holding groove 3 provided in the first and second holding bars 32, 33
As shown in FIG. 5B, 2a and 33a support the weight of the wafer W and are formed in a substantially V-shaped cross section.
Further, as shown in FIG. 5C, the holding grooves 34a and 35a provided in the third and fourth holding rods 34 and 35 have narrow narrow groove portions so as to restrict the inclination of the wafer W in the surface direction. 36
It is formed by a two-step groove having a and a wide opening 36b.

By providing the wafer boat 30 with the four holding rods 32 to 35 as described above, the wafer W can be held in a more stable state as compared with the conventional one having three holding rods. Also, when the orientation flat Wo provided on the wafer W is positioned and held downward, the wafer W can be held in a stable state as well. Further, since the overlapping portion between the wafer W and the holding rods 32 to 35 can be reduced, the contact between the processing liquid and the wafer W can be made uniform.

On the other hand, as shown in FIG. 3, the chemical liquid processing tank 15A of the above processing tanks 15 has an inner tank 16a provided with a triangular notch (not shown) for overflow at the upper end opening, and an inner tank 16a. An overflow tank 16b is provided outside the tank 16a, and a discharge port 16c provided under the overflow tank 16b
And the processing liquid supply port 16d provided in the lower part of the inner tank 16a are connected by a circulation pipe line 17, and the suction pipe 18a, the flow control valve 18b, and the filter are connected to the circulation pipe line 17 in order from the overflow tank side. 18c, the inner tank 1
The processing liquid overflowing from 6a can be circulated and supplied again from the overflow tank 16b into the inner tank 16a. A rectifying plate 19 having a plurality of small holes 19a is arranged in the lower portion of the inner tank 16a, and the processing liquid supplied from the processing liquid supply port 15a is supplied to the wafer boat 30.
The wafer W held at is uniformly contacted. In this case, by providing the inclined pieces 19b facing upward on both sides of the straightening plate 19, the flow of the processing liquid can be made smooth and more uniform processing can be performed.

As shown in FIG. 4, the rinse treatment tank 15B has an inner tank 16a similar to the above-mentioned chemical solution treatment tank 15A.
And an overflow tank 16b for receiving the rinse liquid overflowing from the inner tank 16a, and a rectifying plate 19 for uniformly flowing the rinse liquid onto the wafer W. Further, a pure water supply passage 17A for supplying a rinse liquid, for example, pure water, provided with a pump 18d, a flow rate control valve 18e and a filter 18f to the inner tank 16a is connected to the bottom of the inner tank 16a. Further, a drainage pipe 17B for discharging pure water is connected to a drainage port 16c provided in the overflow tank 16b.

Next, the operation of the semiconductor wafer cleaning apparatus incorporating the cleaning processing apparatus 2 configured as described above will be described. First, when the wafers W stored in the carrier C in units of 25 sheets are supplied to the carry-in unit 1, the carrier transfer arm 7 is driven to transfer the supplied carriers C in units of two to the loader unit 5. Then, the carrier C supplied thereafter is transferred to the standby unit 6 by the carrier transfer arm 7, and the wafer W of the subsequent carrier C is temporarily stored in the standby unit 6.

When the two carriers C are supplied to the loader unit 5, the loader unit 5 is driven to align the orientation flats Wo of the wafers W in the two carriers C in one direction to form 50 wafers W. While positioning, the wafer transfer device 2 is driven to move the wafer chuck 20 onto the loader unit 5. At this time, the rotation arm 24 is rotated by the drive of the drive mechanism 21 of the wafer transfer device 2, and the left and right brackets 2 are also rotated.
5 opens. Next, the loader unit 5 is driven to collectively lift the wafers W from the two carriers C, and the wafer chuck 2
0 and the wafer W are relatively close to each other, and the holding groove 2 of the holding rod 26
The wafer W is held in the 6a.

Wafer chuck 20 holding wafer W
Is moved to the first chemical cleaning device 12a along the transfer path 22 by driving the wafer transfer device 2, and then the wafer chuck 20 is lowered at that position to move the first chemical cleaning device 1a.
Fifty wafers W are delivered to the wafer boat 30 in the processing tank 15A of 2a and immersed in the cleaning processing liquid.

When the cleaning process of the wafer W in the first chemical cleaning device 12a is completed, the wafer chuck 20 of the wafer transfer device 2 collectively receives the wafers W from the wafer boat 30 by the operation opposite to the above case. Next, the wafer is transferred to the wafer boat 30 of the first first water cleaning / cleaning apparatus 13a, and the water cleaning processing is performed by the same operation as described above. Further, the same second water cleaning processing is performed by the next second water cleaning / cleaning apparatus 13b. Complete. After that, the chemical solution treatment and the water washing treatment are repeatedly performed as needed, and the wafer W after the washing treatment is discharged to the next step via the carry-out section 4 in a carrier unit.

In the above embodiment, the case where the cleaning processing apparatus of the present invention is applied to a cleaning apparatus for semiconductor wafers has been described. However, it can be applied to other cleaning apparatuses such as LCD glass substrates and etching apparatuses. Of course.

[0031]

【The invention's effect】

1) According to the cleaning treatment apparatus of claims 1, 2 and 3,
The object to be processed (wafer) can be held in a stable state regardless of the position of the orientation flat and the like, and can be immersed in the processing liquid, so that the processing efficiency can be improved.

2) According to the cleaning processing apparatus of the fourth aspect, it is possible to reduce the overlapping portion of the object to be processed (wafer) and the holding rod as much as possible, and to suppress the accumulation of the liquid due to the stagnation of the processing liquid. In addition to the above, since the contact between the processing liquid and the object to be processed (wafer) can be made uniform, the above 1)
In addition, it is possible to prevent particles from adhering to the object to be processed (wafer), and it is possible to improve the yield.

[Brief description of drawings]

FIG. 1 is a perspective view showing a semiconductor wafer cleaning apparatus to which a cleaning processing apparatus of the present invention is applied.

FIG. 2 is a perspective view showing a wafer transfer state in the present invention.

FIG. 3 is a cross-sectional view showing a chemical treatment tank according to the present invention.

FIG. 4 is a cross-sectional view showing a rinse treatment tank according to the present invention.

FIG. 5 is an enlarged sectional view (a) of the first to fourth holding rods in the present invention, an enlarged sectional view (b) of holding grooves of the first and second holding rods, and third and fourth holding rods. It is an expanded sectional view (c) of the holding groove of.

FIG. 6 is a cross-sectional view showing another holding state of the conventional wafer boat.

[Explanation of symbols]

 15 processing tank 15A chemical liquid processing tank 15B rinse processing tank 30 wafer boat (holding means) 32 first holding rod 33 second holding rod 34 third holding rod 35 fourth holding rod 32a to 35a holding groove 40 base 41 Groove 42 Neck 43 Shoulder 44 Lower surface W Semiconductor wafer (processing target) Wo Orient flat

Claims (4)

[Claims] 1. A processing tank for containing a processing liquid for dipping the object to be processed, and a holding means for holding a plurality of the objects to be processed standing in parallel in the processing tank and holding the object in the processing solution. In the cleaning apparatus, the holding means is positioned below the first and second holding bars, and the first and second holding bars that respectively hold the lower parts on both sides of the object to be processed. The third and fourth holding rods respectively hold both sides of the lower end portion of the object to be processed, and the first and second holding rods have holding grooves for supporting the weight of the object to be processed in the longitudinal direction. In the cleaning processing apparatus, the third and fourth holding rods are provided with holding grooves arranged in the longitudinal direction to prevent the object to be processed from falling. 2. A processing tank containing a processing liquid for dipping a wafer, and a holding means for holding a plurality of the wafers standing in parallel in the processing tank while being immersed in the processing liquid. In the cleaning processing apparatus, the holding means holds first and second holding rods for holding lower portions on both sides of the wafer, and third and fourth holding rods for holding near both sides of an orientation flat provided on the wafer. The first and second holding rods have holding grooves for supporting the weight of the wafer, which are arranged in a row in the longitudinal direction, and the third and fourth holding rods prevent the wafer from falling. The cleaning treatment device is characterized in that the holding grooves are arranged in a row in the longitudinal direction. 3. The cleaning processing apparatus according to claim 2, wherein the distance between the third holding rod and the fourth holding rod is longer than the length of the orientation flat portion of the wafer. 4. The first to fourth holding rods each have a rod-shaped base portion and a plurality of holding grooves extending upward from the upper surface of the base portion such that the width is narrower than the width of the base portion. The base portion has a neck portion extending downward from the groove portion and a shoulder portion inclined downward from the neck portion, and the bottom surface is directed downward. The cleaning processing apparatus according to claim 1 or 2, wherein the cleaning processing apparatus is formed in a convex shape.