JP5274161B2 - Wafer storage rinse apparatus, wafer storage rinse method, and wafer polishing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wafer storing/rinsing device such that no water mark is formed on a surface of a wafer and no damage is made in a process of conveying and cleaning the wafer in a state wherein the wafer is dipped in water after being polished. <P>SOLUTION: A cassette 4 placed over a water surface in a water tank 5 is set horizontally, a nozzle bar 9a of a rinsing mechanism 9 is moved to behind the cassette 4, and wafers 3 having been polished are stored in the cassette 4, one by one. After all the wafers 4 are stored in the cassette 4, the cassette 4 is tilted by a tilting means 8 within a range of 1 to 20&deg;, and rinse water is jetted to surfaces of the wafers 3 by the nozzle bar 9a. Then the cassette 4 is dipped in the water in the water tank 5 at intervals for one wafer by a cassette elevation mechanism 7. Even when the cassette 4 is lifted from the water tank 5, the cassette 4 is tilted by the tilting means 8. Consequently, the wafers 3 have neither damage nor a watermark, and the wafers 3 are effectively cleaned and conveyed. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a wafer storage rinsing apparatus used in a semiconductor manufacturing process, and in particular, a wafer storage rinsing apparatus for storing submerged semiconductor wafers (hereinafter simply referred to as wafers) one by one and rinsing while rinsing, and a wafer storage The present invention relates to a rinsing method and a wafer polishing apparatus provided with the wafer storage rinsing apparatus.

2. Description of the Related Art Conventionally, in a semiconductor manufacturing process, a technique for transporting or cleaning a wafer while storing it in a cassette and submerging it is widely known. For example, in an automatic cleaning apparatus that performs wafer cleaning to drying, a technique is disclosed in which a device forming surface is inclined by a predetermined angle to perform cleaning and drying, and the wafer is transported between processing tanks while being inclined by a predetermined angle. (See Patent Document 1). In addition, there is also disclosed a transfer device that pulls up from a processing tank in a state where a pattern surface of a wafer is held at a predetermined angle with respect to a horizontal direction (see Patent Document 2). Furthermore, in order to prevent the wafer and the cassette from coming into contact with each other during cleaning, a technique in which the wafer is tilted and immersed is also disclosed (see Patent Document 3). Also disclosed is a technique for performing etching, pure water cleaning, IPA drying and the like while tilting the wafer. By tilting the wafer in this way, it is possible to suppress the wraparound of dust and the generation of watermarks from the back surface of the wafer (see Patent Document 4). In addition, a technique related to a mechanism for converting a wafer from a vertical posture to a horizontal posture at the time of cleaning and transporting the wafer is also disclosed (see Patent Document 5).
Japanese Patent No. 3167765 Japanese Patent Laid-Open No. 6-314677 JP-A-8-64570 Japanese Patent Laid-Open No. 10-177988 Japanese Patent No. 3066986

  However, the automatic cleaning apparatus disclosed in Patent Document 1 is designed to prevent the device forming surface of the wafer from coming into contact with the wafer storage jig, and stores the polished wafers one by one in the cassette. Therefore, it cannot be used for a cassette mechanism that submerges them. Furthermore, even if it is assumed that the wafers that have been polished one by one can be stored in the cassette, it is necessary to immerse the cassette in the water every time or lift it from the water, and the process of operating the cassette However, there are many cases of wasteful operation for storing each wafer. As a result, extra particles are often brought into the water, the inside of the water tank becomes dirty, and the throughput becomes very poor.

  In addition, since the transfer device disclosed in Patent Document 2 tilts the pattern surface of the wafer by a predetermined angle and pulls it up from the processing tank, it is possible to suppress the generation of watermarks. The robot cannot be transported and stored. Further, even if the wafer is tilted and pulled up, the wafer is submerged in a substantially vertical state, so that the pattern forming surface of the wafer may hit the slot and come into contact with the wafer storage jig due to the force of water. Moreover, since it has a complicated internal mechanism, when a polished wafer is stored in a cassette, the wafer may come into contact with components of the wafer storage jig.

Moreover, although the technique disclosed in Patent Document 3 can stabilize the posture of the wafer in the cassette by tilting the wafer, it is not a cassette mechanism that can easily store the polished wafer. . Furthermore, in the technique of Patent Document 4, generation of a watermark can be suppressed, but the polished wafer can be easily stored in a small space, the slurry can be completely washed away, or a separate transfer mechanism can be used. There are structural difficulties in taking out a wafer and storing it in a cassette easily. Further, in the technique of Patent Document 5, the mechanism for converting the wafer from the vertical posture to the horizontal posture becomes complicated, the space for changing the posture of the wafer increases, and the space utilization rate deteriorates. There is a problem that the inside of the tank tends to become dirty because there are many parts that operate greatly in conversion. Further, the wafers processed and transferred one by one are not structured to be submerged safely and efficiently with a small amount of movement. Further, no consideration is given to how water existing on the wafer is retreated.

  That is, the conventional wafer storage rinsing apparatus has various problems as described below in the mechanism for storing a polished wafer in a wet state. That is, when the cassette is set up vertically and lifted from the water tank, the wafers may be tilted back and forth in the slot, or the tilt of adjacent wafers may be reversed, and the adjacent wafers may be rubbed due to water tension. is there. Further, when the cassette is lifted from the water tank, when the water flows down from the wafer, a line-shaped stripe is formed and flows down, so that a striped line is formed on the wafer. Similarly, even when the wafer is tilted slightly vertically, the line where water flows down can be striped, and it remains as a watermark. May remain.

  In addition, when a wafer is stored in the cassette by a robot with the cassette standing upright, the wafer is inclined in various directions, and a sufficient interval between the wafers stored in the cassette cannot be secured. Therefore, when inserting a wafer, there is a possibility that the arm of the robot may hit an adjacent wafer. Further, when the cassette is set up substantially vertically, the wafer must be submerged in the water tank between the time when one wafer is inserted and the time when the next wafer is inserted, but the diameter of the wafer is about 300 mm. In this case, it is necessary to raise and lower the wafer by about 300 mm every time in order to submerge the wafer. At this time, since the ascending / descending distance of the wafer is long, work time is lost. In addition, since all the wafers are repeatedly raised and lowered from the water tank, a line where water flows down is formed on the wafer each time, and as a result, a very large number of watermarks may be formed.

  In addition, when the cassette containing the wafer is horizontally lifted, the wafer may swim in the slot due to the surface tension of water, and the wafer surface may be rubbed against the guide groove of the cassette and the wafer may be damaged. Furthermore, when the cassette is leveled and the wafer is submerged in the water tank as it is, the direction in which water enters the wafer varies in various directions for each wafer, which may cause the wafer to swim in the guide groove of the cassette. In addition, the wafer surface may rub against the cassette, scratching the outer periphery of the wafer, or rubbing the water tank to spread the powder and contaminate the water in the water tank. Further, since it is not determined from which part the water flows out on the wafer, the water mark is in various states depending on the wafer. In particular, there is a portion where water accumulates between the guide groove of the cassette and the wafer, and a watermark may be formed there. Further, when the wafer is pulled up, the water adhering to the back surface of the wafer may flow down onto the lower wafer, and the water may form a watermark on the lower wafer.

Therefore, in the process of submerging and transporting and cleaning the wafer after polishing, there arises a technical problem to be solved in order to prevent a watermark from being formed or scratched on the surface of the wafer. The present invention has an object to provide a wafer storage rinsing apparatus, a wafer storage rinsing method, and a wafer polishing apparatus including the wafer storage rinsing apparatus for solving this problem.

The present invention proposes to achieve the above object , and the invention according to claim 1 is an apparatus for storing and rinsing a plurality of wafers for storing and rinsing a polished wafer.
The wafer is stored in multiple stages in the vertical direction, and a storage jig having an opening in one side surface ,
A transfer mechanism for inserting the wafers one by one into the storage jig;
Inclining means for increasing the opening direction of the storage jig into which the wafer is inserted and inclining the storage jig by a predetermined angle;
A water tank for submerging the wafer stored in the storage jig;
It said housing jig which is inclined by the inclination means, an elevating means for elevating the relative direction perpendicular to the water surface in the water tank,
There is provided a wafer storage rinsing apparatus including a rinsing mechanism for rinsing by flowing rinsing water along an upper surface of the storage jig along the surface of the wafer.

  According to such a configuration, at the time of transfer and storage, the polished wafers transferred one by one can be stored in a compact and space-saving manner. In addition, the wafer transfer mechanism at the time of storage can transfer the wafer by a simple horizontal transfer mechanism and efficiently store the wafer. The stored wafer can be immersed in water at any time and stored, and the next wafer can be prepared for storage while the previous wafer is stored in water.

  Next, when the wafer is immersed and stored, the storage jig can be slightly inclined to allow water to enter the wafer gently. In the case of horizontal immersion, the surface tension of water during immersion does not cause initial immersion, but water suddenly enters the wafer surface, causing the wafer to rise and the wafer surface to collide with the edge of the storage jig. This situation will disappear. Even when immersing a wafer, by partially immersing the part where the wafer is stored without immersing the entire storage jig, the lifting and lowering operation of the unnecessary storage jig can be reduced to the minimum necessary. In particular, the wafer can be immersed. During immersion storage of the wafer, the abrasive or the like adhering to the wafer surface slides down along the inclined wafer surface, and the wafer becomes somewhat clean.

  In addition, by flowing rinse water along the inclined wafer surface during immersion, a flow of water is generated on the wafer surface, and the abrasive or the like adhering to the wafer surface further flows down from the wafer surface. Become. The water flowing along the wafer flows along the inclined wafer and is drained from the other end of the wafer. By supplying rinsing water with such a constant flow, it is possible to prevent the wafer from floating due to convection from the bottom by convection, and store the wafer in a stable posture even in the immersed state. It becomes possible.

  When the wafer is lifted from the immersion state, water slowly moves back from the wafer surface. Thereby, water does not remain between wafers, and the wafer can be taken out with good water drainage. Further, when the storage jig is raised, the wafer swims toward the opening, and the wafer does not spill out from the storage jig.

  Further, even when the wafer surface is water-repellent, when the storage jig is lifted while being slightly tilted, the waterfront that retreats on the wafer slowly retreats as a group. Therefore, a water drop does not slide on the wafer surface and a streak line is not formed corresponding to the slipped portion. Similarly, the water droplets existing between the wafer and the storage jig are also drawn back to the surface of the retreating water tank by the gentle inclination. As a result, no excess water remains between the wafer and the storage jig. As a result, water remains between the wafer and the storage jig, and the wafer does not adhere to the storage jig due to the surface tension of the water.

When the wafers are taken out from the raised cassette, the wafers can be taken out by a transfer mechanism that can access the storage jigs one by one after the wafers are drained after being stored in water. Also, when removing wafers, it is possible to lift only the wafers that need to be taken out one by one from the water without taking out all the wafers stored in the storage jig from the water. It becomes.

  According to a second aspect of the present invention, in the first aspect of the present invention, after the transport mechanism transports the wafer and horizontally stores it in a predetermined portion of the storage jig, the tilting means is a front portion of the storage jig. The storage jig is inclined at a predetermined angle with the wafer storage opening at a high position, and the elevating means lowers the storage jig relative to the water in the water tank and immerses it by a predetermined amount. The mechanism is characterized in that the rinse water sprayed along the surface of the wafer is drained from the lower inclined portion at the rear of the storage jig.

  According to such a configuration, the wafer storage opening at the front of the storage jig is raised, and the storage jig is tilted by a predetermined angle and submerged in the water tank. Therefore, the wafer can be submerged efficiently, and there is no possibility of damaging the wafer surface. Further, since the rinse water sprayed along the surface of the wafer by the rinse mechanism is drained from the lower inclined portion of the rear portion of the storage jig, the water flow is uniformly from the upper inclined portion of the wafer to the lower inclined portion of the wafer. It becomes possible to flow like. Since the slurry is also removed along the flow, the wafer surface can be kept clean. In addition, such a uniform water flow makes it possible to maintain a stable posture of the wafer.

According to a third aspect of the invention, the predetermined amount to provide a wafer housing rinsing device according to claim 2, characterized in that the substantially intervals one sheet of the wafer.

  According to such a configuration, the lifting / lowering means lowers the storage jig relative to the water in the water tank and immerses it by an interval corresponding to approximately one wafer. Accordingly, since the wafer does not float, there is no possibility of damaging the surface of the wafer.

  According to a fourth aspect of the present invention, in the first, second, or third aspect of the invention, the rinsing mechanism includes a nozzle bar provided substantially perpendicular to the wafer and a turning mechanism for turning the nozzle bar. When storing the wafer, it is located at a position away from the wafer storage opening of the storage jig, and after storing the wafer, the mechanism moves to the front of the wafer storage opening of the storage jig. .

  According to such a configuration, the nozzle bar of the rinse mechanism moves to a position that does not hinder the conveyance of the wafer when the wafer is stored in the storage jig. After the wafer is stored, the nozzle bar turns in front of the storage jig and is positioned in front of the wafer. Thus, the wafer is prevented from jumping out from the wafer storage opening of the storage jig even by the nozzle bar. Further, a wafer that has slightly jumped out can be stored in the back of the storage jig by the nozzle bar. Next, in the process in which the wafer is tilted and immersed in water, the wafer does not come out of the wafer storage opening, and the entire wafer storage jig is immersed in water with the wafer stored in the wafer storage jig. When immersing in water, the wafer may be immersed while supplying rinse water onto the wafer. At that time, since water is also present on the wafer, it is possible to further eliminate the effect of the wafer floating due to the water. As a result, when the wafer is immersed in water, it is possible to store the wafer in water by gently immersing the wafer. In addition, even during underwater storage, as described above, water is continuously supplied from the nozzle bar, so that the slurry deposited on the wafer can be washed away and the posture of the wafer can be stabilized. .

Further, the invention according to claim 5 is the invention according to claim 4, wherein the nozzle bar is formed with a plurality of nozzles or discharge holes, and the rinse water sprayed from the nozzles or discharge holes inclines the surface of the wafer from the inclined upper part. By flowing out along the lower part, the surface of the wafer is rinsed.

  According to such a configuration, the nozzle bar is formed with a plurality of nozzles or discharge holes at pitch intervals between the wafers stacked and stored in the storage jig, so that each wafer can be reliably rinsed. can do. Moreover, the rinse water rinsed by each wafer is discharged | emitted as a drain collectively along the inclination of the wafer surface.

  According to a sixth aspect of the invention, in the first, second, third, fourth or fifth aspect of the invention, the predetermined angle at which the tilting means tilts the storage jig is in the range of 1 ° to 20 °. It is characterized by.

  According to such a configuration, the tilt angle when the wafer is submerged is in the range of 1 ° to 20 ° with respect to the horizontal plane. Accordingly, water drops are not dropped from the upper wafer to the lower wafer, and there is no possibility that a watermark is generated.

  A seventh aspect of the present invention is a wafer polishing apparatus comprising the wafer storage rinsing apparatus according to the first, second, third, fourth, fifth or sixth aspect.

  According to such a configuration, a wafer polishing apparatus including a wafer storage rinsing apparatus that has a predetermined tilt angle in a storage jig for storing a wafer and is immersed in a water tank for rinsing is realized. From polishing to submerging / cleaning / conveying can be performed in a consistent process.

  The invention according to claim 8 is the wafer storage rinsing method for storing and rinsing the polished wafer, wherein the transport mechanism includes a first step of inserting the wafers into the storage jig one by one, and an inclination means. A second step of tilting the storage jig in which the wafer is stored by a predetermined angle, and a third step in which the lifting means moves the tilted storage jig relative to the water in the water tank. The elevating means performs the fourth step of immersing the wafer stored in the storage jig in the water tank, and the rinse mechanism performs the rinse by injecting rinse water along the surface of the wafer from the inclined upper part of the storage jig. And a fifth step.

  According to such a wafer storage rinsing method, when the transfer mechanism inserts the wafers one by one into the storage jig, the inclination means inclines the storage jig in which the wafers are stored by a predetermined angle, and the elevating means inclines. Raise and lower the storage jig relative to the water in the water tank. Thus, the wafer stored in the storage jig can be effectively submerged in the water tank without damaging the wafer. At this time, the rinse mechanism sprays rinse water along the surface of the wafer from the inclined upper part of the storage jig to rinse the wafer (that is, rinse), so that the wafer can be efficiently cleaned.

  According to a ninth aspect of the present invention, in the wafer storage rinsing process for storing and rinsing the polished wafer, the first mechanism in which the transfer mechanism inserts the wafers one by one into the storage jig, and the tilting means is the wafer. A second step of tilting the storage jig stored therein by a predetermined angle, a third step of moving the storage jig inclined by the lifting means relative to the water in the water tank, and the lifting means A fourth step of immersing the wafer stored in the storage jig in the water tank, and a fifth step of rinsing the rinse mechanism by spraying rinse water along the surface of the wafer from the inclined upper part of the storage jig; In the wafer removal process for removing the stored wafer, the wafer storage jig inclined by the elevating means is relatively gently lifted, and the wafer storage process is performed after the wafer is lifted from the water surface. A step of horizontally, characterized in that it comprises a step of taking out the wafer by a separate transport mechanism from the wafer housing jig horizontal.

  According to such a wafer storage rinsing method, the rinsing mechanism performs the process of rinsing the wafer by spraying the rinsing water along the surface of the wafer from the upper inclined portion of the storage jig, so that the wafer is cleaned. Furthermore, it can be performed efficiently.

  According to the first aspect of the present invention, it is possible to efficiently store wafers that are polished and transported at regular intervals. Further, the wafer can be efficiently submerged without large operation after the wafer is stored, and the wafer posture is stable, so there is no possibility of the wafer rubbing against the cassette in the water tank. In addition, since the rinse mechanism flows rinse water along the surface of the wafer from the inclined upper part of the storage jig to rinse the wafer (that is, rinse), the wafer can be cleaned efficiently.

  According to the second aspect of the present invention, since the storage jig is inclined and submerged in the water tank so as to raise the wafer storage opening at the front of the storage jig, the wafer can be submerged efficiently. There is no risk of damaging the wafer surface. Moreover, since the rinse water rinsed along the surface of the wafer by the rinse mechanism is drained from the lower inclined portion at the rear of the storage jig, the wafer can always be rinsed with clean pure water.

  According to the third aspect of the present invention, when the storage jig is inclined and submerged in the water tank, the wafer is not lifted because the wafer is not lifted because the wafer is immersed only for one interval. There is no risk of injury. Further, since the upper wafer does not drop droplets on the lower wafer, there is no possibility that a watermark is formed on the surface of the wafer.

  According to the invention of claim 4, the nozzle bar of the rinsing mechanism moves to a position that does not hinder the conveyance of the wafer when the wafer is stored in the storage jig, and rinse water is supplied to the wafer surface when rinsing the wafer. Since it moves to a place where it can be sprayed, the wafer can be effectively rinsed.

  According to the invention described in claim 5, since the nozzle bar of the rinse mechanism is formed with a plurality of nozzles or discharge holes at a pitch interval of the wafers stacked and stored in the storage jig, one wafer at a time Can be reliably rinsed. Further, since the water cleaned by each wafer is discharged as a drain all along the inclination of the wafer surface, the wafer surface can always be rinsed with pure water.

  According to the sixth aspect of the present invention, since water droplets are not drawn from the upper wafer to the lower wafer, there is no possibility that a watermark is generated on the surface of the wafer.

  According to the seventh aspect of the present invention, since the wafer polishing apparatus including the wafer storage apparatus that has the inclination angle and is submerged in the water tank for cleaning is realized, the wafer polishing, cleaning, and conveyance are consistent. It can be performed in a process.

  According to the invention described in claim 8, since the wafer can be efficiently stored and immersed and washed, and then the wafer can be sequentially sent out to the transfer mechanism, so that the wafer is frequently removed from the water tank during the transfer. There is no need to put in and out, and immersion and cleaning can be performed in a stable state. At this time, the rinsing mechanism sprays rinsing water along the surface of the wafer from the upper inclined portion of the storage jig to rinse the wafer (that is, rinse), so that the wafer can be cleaned efficiently.

According to the ninth aspect of the invention, since the rinsing mechanism performs the process of rinsing the wafer by spraying the rinsing water along the surface of the wafer from the inclined upper part of the storage jig, the wafer is further cleaned. Can be done efficiently.

  In order to achieve the object of preventing water marks and scratches from being made on the surface of a wafer in the process of submerging and transporting the wafer after polishing the wafer, the present invention accommodates and rinses the polished wafer. In a wafer storage rinsing apparatus, a storage jig for storing wafers, a transport mechanism for inserting the wafers one by one into the storage jig, and an inclination means for tilting the storage jig into which the wafers are inserted by a predetermined angle A water tank for immersing the wafer stored in the storage jig, an elevating means for moving the storage jig inclined by the inclination means relative to the water in the water tank, and an inclined upper part of the storage jig This is realized by providing a wafer storage rinsing apparatus including a rinsing mechanism for rinsing by flowing rinsing water along the surface of the wafer.

  Hereinafter, embodiments of the wafer storage rinse apparatus of the present invention will be described in detail with reference to FIGS. 1A and 1B show a wafer storage rinse apparatus according to an embodiment of the present invention configured in a wet cassette station, where FIG. 1A is a plan view and FIG. 1B is a side view.

  In the figure, the wet cassette station 1 includes two sets of wafer storage rinse apparatuses 2. Since all the wafer storage rinse apparatuses 2 have the same configuration, only the wafer storage rinse apparatus 2 on the right side of the drawing will be described with reference numerals. The wafer storage rinsing apparatus 2 includes a cassette (storage jig) 4 for storing the polished wafer 3, a water tank 5 for submerging the wafer 3 stored in the cassette 4, and one wafer 3 at a time. 4, a transport mechanism 6 for storing in the cassette 4, a cassette lifting / lowering mechanism (lifting / lowering means) 7 that lifts and lowers the cassette 4 relative to the water in the water tank 5, an inclination means 8 that tilts the cassette 4 by a predetermined angle, A rinse mechanism 9 including a turning mechanism 9b is provided.

  As such a cassette 4, a stable cassette 4 that does not float even when immersed in water is used. For example, a Teflon (registered trademark) cassette 4 made of PTFE, PFA, or the like is desirable.

  The cassette elevating mechanism 7 elevates and lowers the cassette 4 by a servo motor and ball screw mechanism, and the elevating speed at this time can be varied at a speed of 5 to 30 mm / sec. The tilting means 8 can tilt the cassette 4 by a predetermined angle by the mechanism of the air cylinder, but can tilt the cassette 4 by a servo motor.

  Although not shown in FIG. 1, the wafer storage rinsing apparatus 2 is not suitable for a drain valve for draining the water in the water tank 5, a publishing function attached to a jump-out preventing means of the drain valve, or a sealed container. A function of filling active gas or IPA gas is provided. Further, the wafer storage rinsing apparatus 2 includes a nozzle bar 9a and has a function of preventing the wafer 3 from swimming forward, or rinsing water from the nozzle bar 9a to wash away the slurry on the surface of the wafer 3. . Further, the wafer storage rinsing apparatus 2 is configured to perform a stopper function of the nozzle bar 9a, or to set the water level of the water tank 5 by one wafer 3 below the running water cleaning portion.

  Next, a mechanism in which the wafer storage rinsing apparatus 2 rinses the wafer 3 and a mechanism in which the cassette 4 is submerged in the water tank 5 will be described. FIG. 2 is an explanatory view showing a state in which the polished wafer 3 is stored in the cassette 4 of the wafer storage rinse apparatus 2 in the wafer storage rinse apparatus 2 shown in FIG. 1, and (a) shows the rinse mechanism 9 from above. The top view conceptually viewed, (b) is a side view of the wafer storage rinse apparatus 2.

  FIG. 3 is an explanatory view showing a state in which the wafer rinse storage device 2 storing the wafer 3 is inclined and rinsed in the water tank 5 while being rinsed. FIG. 3A is a conceptual view of the rinse mechanism 9 from above. FIG. 4B is a side view of the wafer storage rinse apparatus 2. 2 and 3, the left side of the drawing is a wafer storage opening at the front portion of the cassette 4 in which the wafer 3 is taken in and out.

  As shown in FIG. 2, the cassette 4 is stored inside the cassette table 4a. However, when the polished wafer 3 is stored in the cassette 4, the cassette table 4a and the cassette 4 are placed in a horizontal state. . At this time, the cassette stand 4 a and the cassette 4 are placed above the water surface of the water 5 a inside the water tank 5. Further, as shown in FIG. 2A, the rinsing mechanism 9 rotates the nozzle bar 9 a to the rear part of the cassette 4 by a turning mechanism 9 b. In this state, as shown in FIG. 2B, the wafer storage opening at the front of the cassette 4 is opened, so that the wafer 3 after polishing by the transfer mechanism 6 is put into the cassette 4 by one sheet. Can be stored one by one.

  Next, after all the wafers 3 are accommodated in the cassette 4 by the transport mechanism 6, the rinse mechanism 9 moves the nozzle bar 9a to the front portion (front surface) of the cassette 4 by the turning mechanism 9b as shown in FIG. Swivel to the opening). Furthermore, the tilting means 8 tilts the cassette base 4a and the cassette 4 by a predetermined angle. Then, the nozzle bar 9 a is slightly swung while rinsing water is ejected from the nozzle bar 9 a, and the cassette table 4 a and the cassette 4 are submerged in the water 5 a inside the water tank 5 by the cassette lifting mechanism 7 (see FIG. 1). In addition, it is desirable that the inclination angle by which the inclination means 8 inclines the cassette base 4a and the cassette 4 is in the range of 1 ° to 20 ° with respect to the vertical axis of the water surface of the water 5a in the water tank 5.

  Further, as a method different from the above embodiment, the wafer 3 may be cleaned in a state where the cassette table 4 a and the cassette 4 are submerged in the water tank 5. Also, when the cassette table 4 a and the cassette 4 are pulled up from the water tank 5, the cassette table 4 a and the cassette 4 are pulled up with the tilting means 8 tilted.

  In this way, the nozzle bar 9a of the rinsing mechanism 9 moves to a position that does not hinder the conveyance of the wafer 3 when the wafer 3 is stored in the cassette 4 (the rear part of the cassette 4), and when the wafer 3 is rinsed, the wafer 3 Since it moves to the position (front part of cassette 4) which can spray rinse water on the surface of 3, conveyance and rinse of wafer 3 can be performed efficiently.

  In addition, since a plurality of nozzles or discharge holes are formed in the nozzle bar 9a at a pitch interval of the wafers 3 stacked on the tray of the cassette 4, the rinse water sprayed from the nozzles or discharge holes is for each sheet. It is sprayed on the surface of the wafer 3 and can be rinsed reliably. Furthermore, since the rinse water that has been rinsed flows out from the upper inclined portion of each wafer 3 along the lower inclined portion, the slurry on the surface of the wafer 3 is surely washed off and discharged from a drain port (not shown). In this way, each wafer 3 can be reliably rinsed.

  That is, as shown in FIG. 2, the polished wafer 3 is stored in a horizontal state in a predetermined portion in the cassette 4 by the transfer mechanism 6, and after the wafer 3 is stored, the wafer storage opening of the cassette 4 is set as the front surface. The front surface of the cassette 4a and the cassette 4 are inclined by a predetermined angle (1 ° to 20 °) by the tilting means 8. Then, while rinsing the wafer 3 with the nozzle bar 9a of the rinsing mechanism 9, the cassette raising / lowering mechanism 7 (see FIG. 1) lowers the cassette table 4a and the cassette 4 into the water 5a in the water tank 5 so that a predetermined amount (for example, The wafer 3 is cleaned by immersing it by an interval of one wafer 3).

Next, the flow of processing from when the polished wafer 3 is transported by robot until it is submerged in the water tank of the wafer storage rinse apparatus will be described with reference to the flowchart of FIG. 4 and FIGS. FIG. 4 is a flowchart showing the flow of processing from wafer transfer to submergence in the wafer storage rinse apparatus of the present invention, and FIGS. 5A to 5D illustrate the behavior of water and the like with respect to the wafer during submersion. It is a figure for doing.

  First, the cassette 4 stands by horizontally on the water tank 5 (step S1). Next, the nozzle bar 9a is swung to the rear part of the cassette 4 by the swiveling mechanism 9b of the rinse mechanism 9 (step S2). Further, the wafer 3 is inserted into the slot of the cassette 4 by the robot (transfer mechanism 6) (step S3). Then, the front opening (wafer storage opening) at the front of the cassette 4 is slightly raised and inclined (step S4).

  Next, the nozzle bar 9a is swung to the front portion (front opening portion) of the cassette 4 by the swiveling mechanism 9b of the rinse mechanism 9 (step S5). Then, rinsing water is sprayed toward the surface of the wafer 3 by the nozzle bar 9a to perform rinsing (step S6), and the wafer 3 in the cassette 4 is slowly immersed in the water tank 5 (step S7). In this way, the cassette 4 is lowered into the water tank 5 by one slot at a time.

  That is, when the wafer 3 is immersed in the water 5a in a horizontal state as in the prior art (FIG. 5A), the wafer 3 is lifted by the buoyancy of the water, and the surface of the wafer 3 comes into contact with the periphery of the cassette 4 3 may be damaged. Further, the surface tension of the water 5a causes the water 5a to swell at the outer peripheral portion of the wafer 3, and the water 5a may enter the surface of the wafer 3 from a random direction (FIG. 5B).

  Therefore, in order to eliminate such problems, the direction in which the water 5a enters the wafer 3 is from the front opening side of the cassette 4 by immersing the wafer 3 in the water tank 5 while tilting the wafer 3 (FIG. 5C). It becomes a certain direction toward the rear surface. Furthermore, since the inclination angle of the wafer 3 is as gentle as 1 ° to 20 °, the water 5a slowly enters the surface portion of the wafer 3, so that there is no possibility that the wafer 3 is lifted (FIG. 5D). Further, since the water level rises along the groove of the cassette 4, the water 5 a rises smoothly onto the wafer 3. This makes it possible to cleanly immerse and clean the surface without damaging the wafer 3.

  Next, the flow of processing when the wafer 3 is pulled up from the state stored in water and taken out will be described with reference to the flowchart of FIG. 6 and FIGS. 7A to 7E. FIG. 6 is a flowchart showing a flow of processing from the submerged state until the wafer is pulled out and taken out in the wafer storage rinse apparatus of the present invention, and FIGS. 7A to 7D show water to the wafer when the wafer is lifted from the submerged state. It is a figure for demonstrating the behavior of.

  In the flowchart of FIG. 6, the wafer 3 exists while being immersed in water while being rinsed in an inclined state (step S11). From this state, first, the nozzle bar 9 a turns and comes to be located outside the cassette 4. Next, the cassette elevating mechanism 7 slowly raises the cassette 4 while maintaining the inclined state (step S12). Then, the water deposited on the wafer 3 is slowly retracted from the surface of the wafer 3 when the wafer 3 rises (step S13). Thereby, water does not remain between the wafers 3, and the wafer 3 can be taken out with good water breakage.

Further, when the cassette 4 is raised, the wafer 3 swims toward the opening, and the wafer 3 does not spill out from the cassette 4. Further, even when the surface of the wafer 3 is water-repellent, when the cassette 4 is lifted while being slightly inclined, the waterfront that moves backward on the wafer 3 slowly moves back together. Therefore, a water drop does not slide on the surface of the wafer 3 and a streak line is not formed corresponding to the slipped portion. Similarly, the water droplets existing between the wafer 3 and the cassette 4 are also drawn back to the surface of the water in the retreating water tank 5 by a gentle inclination. As a result, no excess water remains between the wafer 3 and the cassette 4. As a result, water remains between the wafer 3 and the cassette 4, and the wafer 3 does not adhere to the cassette 4 due to the surface tension of the water. In other words, since water slides down from the surface of the wafer 3 quickly, no trace (watermark) of water sliding down is formed.

  Next, after the wafer 3 is lifted from the water together with the cassette 4, the cassette 4 is returned to a horizontal state (step S14). At this time, the wafer 3 to be taken out is positioned higher than the water, but the next wafer 3 remains stored in the water. In this state, the wafer 3 in the cassette 4 is taken out by another robot transfer mechanism 6 (step S15). Then, the taken-out wafer 3 is transferred as it is and moved to the next process (step S16).

  At this time, by placing the wafer 3 in a horizontal state, the robot transport mechanism 6 can be easily taken out, and transport to the next process is facilitated. At this time, without removing all the wafers 3 contained in the cassette 4 from the water, only the wafers 3 to be taken out one by one in order from the top may be lifted from the water to take out the wafers 3. By doing so, it is not necessary to perform an inefficient method of pulling the wafer 3 out of water each time and immersing it again.

  Although the mechanism for raising and lowering the cassette 4 is shown here, the cassette 4 may be raised and lowered relative to the water surface. Therefore, the cassette 4 is fixed at that position and the water surface is raised and lowered. Good. Here, since raising and lowering of the cassette 4 also means raising and lowering relative to the water surface, the water surface may be raised and lowered by increasing or decreasing the amount of water.

  By doing so, it becomes possible to make it very easy to store the wafer 3 in a dipping process and to access the subsequent single wafer process. It becomes possible to wash. Note that the method of relatively lifting the cassette 4 containing the wafer 3 from the water may be a method of draining water instead of the cassette lifting mechanism.

  As described above, when the wafer 3 is pulled up from the submerged state, the wafer 3 is brought into a gentle inclined state (FIG. 7A), so that the water on the surface of the wafer 3 is the water in the retreating water tank 5. They slowly slide together as if dragged to the surface (FIG. 7B). Thereby, a watermark is not formed on the surface of the wafer 3. Further, a large force is not required for lifting the wafer 3. And after pulling up on water, the wafer 3 is made into a horizontal state, so that the robot transport mechanism 6 can be easily taken out and transported to the next process.

  On the other hand, if the wafer 3 is placed in a horizontal state when the wafer 3 is pulled up from the submerged state (FIG. 7C), the direction in which the water flows on the wafer 3 cannot be determined. Marks may be formed in various states. In addition, since water accumulates on the wafer 3 and water accumulates between the upper and lower wafers 3 (FIG. 7D), a large force is required to pull up the wafer 3.

  Further, as shown in FIG. 7E, when the wafer 3 is sharply inclined when the wafer 3 is pulled up from the submerged state, the force of retreating water as a group on the surface of the wafer 3 becomes difficult to work. In addition, a streak line may be formed on the surface portion of the wafer 3 from which water has flowed down. Further, since a very long operating range is required for lifting the wafer 3, it is not suitable for lifting the wafers 3 one by one.

  As described above, the wafer storage rinsing apparatus of the present invention can efficiently store wafers that are polished and transported at regular intervals. Further, since the wafer storage rinse apparatus of the present invention does not use a complicated mechanism, it is easy to access other transfer mechanisms. Furthermore, according to the wafer storage rinse apparatus of the present invention, the wafer can be submerged efficiently without large operation after the wafer is stored. At this time, since the posture of the wafer is stable, there is no possibility that the wafer will rub against the cassette.

  Also, according to the wafer storage rinse apparatus of the present invention, wafers can be stocked sequentially in a space-saving manner, and the upper wafer does not drop droplets on the lower wafer, so that a watermark is formed on the wafer surface. There is no fear. In addition, the wafer can be efficiently stored and immersed and washed, and then the wafer can be sent out to the transport mechanism in order, so that the wafer is not frequently taken in and out of the water tank at the time of transport. Soaking and cleaning can be performed in the state.

  Further, when the wafer is stored substantially vertically in the cassette, the streak line and the water mark that are noticeable when water flows down when the water repellent surface is used when draining water can be eliminated. Further, when the wafers are stored in the cassette, it is possible to prevent the intervals between the wafers from varying and the wafers from being rubbed. Further, the wafers can be sequentially stored in the cassette and submerged without repeatedly taking out and taking out the wafers from the water tank. At this time, when the wafer is immersed, the wafer surface can be gently immersed without hitting the cassette. Further, when the wafer is taken out from the immersed state, the water slowly moves back on the wafer surface, so there is no possibility that a watermark is formed.

  Further, according to the wafer storage rinsing apparatus of the present invention, since the rinsing mechanism is provided, the rinsing water can be uniformly sprayed from the nozzle bar onto the surface of each wafer, thereby effectively rinsing. In addition, the nozzle bar can always be moved to the optimum position when the wafer is carried into the cassette and when the wafer is rinsed, so that the process from storing the wafer after polishing to cleaning and transporting can be performed efficiently. it can.

  The present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

The wafer accommodation rinse apparatus based on the Example of this invention comprised by the wet cassette station is shown, (a) is a top view, (b) is a side view. In the wafer storage rinse apparatus shown in FIG. 1, it is explanatory drawing which shows the state which accommodates the wafer after grinding | polishing in the cassette of a wafer storage rinse apparatus, (a) is the top view which looked at the rinse mechanism notionally from the upper part, ( b) is a side view of the wafer storage rinse apparatus. It is explanatory drawing which shows the state immersed in a water tank, inclining and rinsing the wafer storage rinse apparatus in which the wafer was accommodated, (a) is the top view which looked at the rinse mechanism notionally from the upper part, (b) The side view of a wafer storage rinse apparatus. The flowchart which shows the flow of a process from the robot conveyance of a wafer to the rinse and submergence in the wafer storage rinse apparatus of this invention. It is a figure for demonstrating the behavior of the water etc. with respect to the wafer at the time of submergence, (a) is a figure which shows the aspect which immerses a wafer in water in a horizontal state, (b) is underwater in the state of (a). The figure which shows the state which water rises in the outer peripheral part of a wafer by the surface tension of water when it is immersed in (c), the figure which shows the state which immerses the wafer while inclining, (d) is the state of (c) The figure which shows that water permeates the surface part of a wafer gradually when it is made to immerse in water by. The flowchart which shows the flow of a process at the time of picking up a wafer from the state which stored the wafer in the water, and taking out a wafer in the wafer storage rinse apparatus of this invention. It is a figure for demonstrating the behavior of the water etc. with respect to a wafer at the time of pulling up from a submerged state, (a) is a figure which shows the aspect which pulls up a wafer in an inclined state, (b) is when pulling up a wafer in the state of (a) The figure which shows that water slides down on the wafer surface gently, (c) is a figure which shows the aspect which pulls up a wafer in a horizontal state, (d) is water on a wafer when a wafer is pulled up in the state of (c). The figure which shows that water accumulates between upper and lower wafers, and (e) is a figure which shows the aspect which pulls up a wafer in a steep inclination state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wet cassette station 2 Wafer storage rinse apparatus 3 Wafer 4 Cassette (storage jig)
4a cassette stand 5 water tank 5a water 6 transport mechanism 7 cassette lifting mechanism (lifting means)
8 Inclination means 9 Rinsing mechanism 9a Nozzle bar 9b Turning mechanism

Claims (9)

In an apparatus for storing and rinsing a plurality of wafers for storing and rinsing the polished wafer,
The wafer is stored in multiple stages in the vertical direction, and a storage jig having an opening in one side surface ,
A transfer mechanism for inserting the wafers one by one into the storage jig;
Inclining means for increasing the opening direction of the storage jig into which the wafer is inserted and inclining the storage jig by a predetermined angle;
A water tank for submerging the wafer stored in the storage jig;
It said housing jig which is inclined by the inclination means, an elevating means for elevating the relative direction perpendicular to the water surface in the water tank,
A wafer storing and rinsing apparatus comprising: a rinsing mechanism for rinsing by flowing rinsing water along the surface of the wafer from an inclined upper portion of the storing jig.   After the transport mechanism transports the wafer and horizontally stores it in a predetermined portion of the storage jig, the tilting means stores the wafer storage opening at a front position of the storage jig at a high position. The jig is inclined by a predetermined angle, the lifting means lowers the storage jig relative to the water in the water tank and immerses the storage jig by a predetermined amount, and the rinse mechanism is on the surface of the wafer. 2. The wafer storage rinse apparatus according to claim 1, wherein the rinse water sprayed along the line is drained from an inclined lower portion of the rear portion of the storage jig.   3. The wafer storage rinsing apparatus according to claim 1, wherein the predetermined amount is an interval of approximately one wafer.   The rinsing mechanism includes a nozzle bar provided substantially perpendicular to the wafer and a turning mechanism for turning the nozzle bar, and the nozzle bar is separated from the wafer storage opening of the storage jig when the wafer is stored. 4. The wafer storage rinsing apparatus according to claim 1, wherein the wafer storage rinse apparatus is located at a location and moves to the front surface of the wafer storage opening of the storage jig after the wafer is stored.   A plurality of nozzles or discharge holes are formed in the nozzle bar, and the rinse water sprayed from the nozzles or the discharge holes flows out from the upper surface of the wafer along the lower surface of the wafer. The wafer storage rinsing apparatus according to claim 4, wherein the wafer storage rinsing apparatus is rinsed.   6. The wafer storage rinsing apparatus according to claim 1, wherein a predetermined angle at which the tilting unit tilts the storage jig is in a range of 1 ° to 20 °.   A wafer polishing apparatus comprising the wafer storage rinse apparatus according to claim 1, 2, 3, 4, 5 or 6. In the wafer storage rinsing method for storing and rinsing the polished wafer,
A transport mechanism, a first step of inserting the wafers one by one into a storage jig;
A tilting means tilts the storage jig storing the wafer by a predetermined angle, and an elevating means moves the tilted storage jig relative to the water in the water tank. A third step of raising and lowering;
A fourth step in which the elevating means submerges the wafer stored in the storage jig in the water tank;
A rinsing mechanism includes a fifth step of rinsing by spraying rinsing water along the surface of the wafer from the upper inclined portion of the housing jig. In the wafer storage rinse process for storing and rinsing the polished wafer,
A transport mechanism, a first step of inserting the wafers one by one into a storage jig;
A second step in which the tilting unit tilts the storage jig storing the wafer by a predetermined angle;
A third step in which the elevating means raises and lowers the inclined storage jig relative to the water in the water tank;
A fourth step in which the elevating means submerges the wafer stored in the storage jig in the water tank;
A rinsing mechanism includes a fifth step of performing rinsing by spraying rinsing water along the surface of the wafer from the inclined upper portion of the storage jig;
In the process of taking out the wafer to take out the stored wafer,
A step of raising the inclined wafer storage jig relatively gently, a step of leveling the wafer storage jig after lifting the wafer from the water surface, and a leveled wafer storage jig And a step of taking out the wafer by another transport mechanism.

Images