KR20110028126A - Rotary type polishing apparatus for wafer - Google Patents

Abstract

PURPOSE: A rotary type apparatus for a wafer is provided to rotate a center robot on the center of a circle when a plurality of polishing units is arranged on the circle, thereby miniaturizing the polishing apparatus. CONSTITUTION: A wafer to be processed and a processed wafer are loaded in a cassette(10). The first vertical moving unit(20) is combined with one side of the cassette to vertically move the cassette. A plurality of polishing units polishes the rear side of a wafer. A center robot(60) moves wafers located in the polishing units respective to a next process at the same time. The second vertical moving unit(40) is combined with one side of a cleaning unit(30) to vertically move the cleaning unit.

Description

Rotary type polishing apparatus for wafer

The present invention relates to a rotary polishing apparatus for a wafer, and more particularly, a center robot is rotatably installed at a center of a concentric circle in a state in which a wafer loaded in one apparatus and a plurality of polishing units are arranged concentrically. Once the polishing process of the pair of wafers withdrawn from the cassette and located in the polishing zones is completed, the process can be moved to the next process at the same time, thereby miniaturizing the device, thereby significantly reducing the required installation area and simultaneously polishing and The present invention relates to a rotary polishing apparatus for wafers which can be transported to significantly shorten the travel time between the processes, reduce the working time, and thereby significantly improve the productivity.

Wafers, which have undergone a series of semiconductor manufacturing processes, are subjected to back polishing before being separated into individual chips. The back polishing process of the wafer is a process for polishing and thinning the back surface of a thickly manufactured wafer to prevent the impact from external impacts during the whole process or transfer.

Sapphire wafers with a thickness of about 450 μm are typically used. The wafer backside grinding process is performed at 85 μm. The final thickness of the wafer may vary depending on the type of semiconductor product or the customer's requirements. Can be.

The wafer backside polishing process includes a grinding step of polishing the wafer so that the thickness of the wafer is about 250 μm from the initial thickness, a lapping step of polishing the wafer to about 110 μm from the wafer thickness of the grinding step, and a polishing liquid on the back side of the wafer polished in the lapping step. The polishing step may be performed in order of polishing to a final thickness, and a cleaning step of cleaning the surface of the polished wafer.

However, in the conventional wafer back polishing apparatus, the grinding step, the lapping step and the polishing step are performed separately in each device, and each wafer is purchased according to the device purchase cost while purchasing each device to perform the above process separately. There was a problem that the unit price increased.

In addition, a large installation area is required to install each device for performing the grinding, lapping and polishing steps as well as moving the wafer for the next process after each step. As the working time increases, there is a problem that the productivity is significantly reduced.

The present invention has been made to solve the above problems, an object of the present invention is to rotate the center robot in the center of the concentric circle in the state in which the wafer is stacked in a single apparatus and a plurality of polishing units arranged in a concentric circle When the polishing process of a pair of wafers, each of which is drawn out from the cassette and located in a plurality of polishing units, is completed, the process can be moved to the next process at the same time, thereby miniaturizing the device. It is to provide a rotary polishing device for a wafer that can be polished and transported at the same time to significantly shorten the movement time between the processes, the working time, thereby significantly improving the productivity.

In addition, in consideration of the fact that the lapping process takes about twice as long as the grinding and polishing process, the lapping unit is separated into the first lapping unit and the second lapping unit, and the lapping process is performed in the first lapping unit and the second lapping unit. The grinding, lapping, and polishing processes are completed at the same time, so that the center robot can simultaneously transfer the wafers located in the polishing zones to the next process, thereby reducing the delay time during the process and thus significantly reducing the work time. The present invention provides a rotary polishing apparatus for a wafer.

In addition, when the process is performed in the polishing unit, a loading arm is further formed in the cassette direction from one side of the rotating plate between the rotating bar positioned between the grinding unit and the cassette and the rotating bar positioned between the polishing unit and the cassette, and the polishing process is performed. A wafer polishing machine that can shorten the working time and significantly improve productivity by preventing the delay of other polishing processes for loading the wafer into the cassette by loading the wafer which has been cleaned and dried in the cassette. In providing.

According to an aspect of the present invention for achieving the above object, at least one cassette (CASSETTE) on which the wafer to be processed and the processed wafer is loaded, and the first installed on one side of the cassette, and swinging the cassette And a plurality of polishing portions disposed on the concentric circles with the cassette, the polishing portion for polishing the back surface of the wafer drawn out from the cassette, a rotating plate rotatably installed at the center of the concentric circles, and the polishing portions; A rotating arm including a rotating arm extending outwardly from one side of the corresponding rotating plate and rotatably coupled to a front end of the rotating bar and disposed vertically in a rotational direction at the front end of the rotating bar, And a grip portion having a grip means for gripping the finished wafer, wherein the grip portion is rotated. A center robot which simultaneously transfers wafers respectively positioned in the plurality of polishing units to the next process while receiving wafers to be processed from the transfer robot, a rotating unit which is coupled to the center of the center robot and provides rotational force to the center robot; And a second shandong movement means coupled to one side of the center robot and moving the center robot, wherein at least two rotation bars of the plurality of rotation bars extend from one side of the rotation plate, and the support arm. Provided is a rotary polishing device for a wafer, comprising a sliding portion slidably coupled from an arm.

The polishing part may include a grinding part for polishing the back surface of the wafer drawn out from the transfer robot, a lapping part for regrinding the back surface of the wafer polished by the grinding part, and a wafer polished precisely by the lapping part. It may include a polishing unit for applying a polishing liquid to the back surface to finally polish the back surface of the wafer.

The lapping unit may include a first lapping unit that primarily performs a first precision polishing on a rear surface of the wafer to be processed and a second lapping unit which secondarily performs a second precision polishing on a rear surface of a wafer moved from the first lapping unit. .

In addition, the grip means may vacuum-absorb the wafer.

In addition, it is preferable to further include a washing unit installed in the lower portion of the cassette, the washing unit for cleaning and drying the polished wafer, and a third shandong unit installed on one side of the cleaning unit and moving the cleaning unit.

When the center robot performs a process in the polishing part, the center robot moves from one side of the rotating plate between the grinding bar and the cassette to the cassette and the rotating bar located between the polishing part and the cassette. It may further include a loading arm extending.

According to the present invention as described above, the wafer is loaded in one device, and the center robot is rotatably installed at the center of the concentric circles in a state in which the plurality of polishing units are arranged concentrically, and the plurality of polishing units are drawn out from the cassette. When the polishing process of a pair of wafers located at each end is completed, it can be moved to the next process at the same time to reduce the size of the device. The required installation area is notably reduced, and the pairing wafers are simultaneously polished and transported to increase the travel time between the processes. Significantly shortened, the working time is shortened, thereby improving the productivity significantly.

In addition, in consideration of the fact that the lapping process takes about twice as long as the grinding and polishing process, the lapping unit is separated into the first lapping unit and the second lapping unit, and the lapping process is performed in the first lapping unit and the second lapping unit. The grinding, lapping, and polishing processes are completed at the same time, so that the center robot can simultaneously transfer the wafers located in the polishing zones to the next process, thereby reducing the delay time during the process and thus significantly reducing the work time. It can be effected.

In addition, in the case of performing the process in the polishing unit, a loading arm is further formed in the cassette direction from one side of the rotating plate between the rotating bar positioned between the grinding unit and the cassette and the rotating bar positioned between the polishing unit and the cassette, and the polishing process is performed. By loading the wafer, which has been cleaned and dried, in the cassette, it is possible to prevent other polishing processes from being delayed for loading the wafer into the cassette, thereby shortening the working time and significantly improving the productivity.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of a rotary polishing apparatus for a wafer according to an embodiment of the present invention, Figure 2 is a plan view of a rotary polishing apparatus for a wafer according to an embodiment of the present invention, Figure 3 is an embodiment of the present invention It is a perspective view of the center robot, the rotating portion and the moving means.

As shown in Figures 1 and 2, the rotary polishing apparatus 1 for a wafer according to an embodiment of the present invention comprises a cassette 10, a first shandong means 20, a cleaning unit 30, 2 is configured to include a shankdong means 40, a grinding unit 50, a center robot 60, a rotating unit 70 and a third shankdong means (80).

The cassette 10 is formed in a substantially box shape, and although not shown in the drawing, an accommodation space (not shown) is formed therein, and includes a partition plate (not shown) for dividing the accommodation space into a plurality of spaces. The wafer to be processed and the wafer to be processed are loaded.

The cassette 10 may be provided in plurality up and down depending on the number of wafers to be processed and wafers to be processed.

The first shandong movement means 20 is coupled to one side of the cassette 10 to move the cassette 10. When the center robot 60 to be described later intends to withdraw a wafer loaded on the cassette 10, the cassette is moved. It serves to move the 10 to the position corresponding to the center robot 60.

The cleaning unit 30 is installed under the cassette 10 and serves to clean and dry the contaminated wafer in the polishing process by receiving the completed wafer until the polishing process.

It is apparent that such a cleaning unit 30 is well known to be able to purchase and use commercially available ones having ordinary skill in the art, and detailed construction and operation description thereof will be omitted.

The second shangdong means 40 is coupled to one side of the cleaning unit 30 to move the cleaning unit 30, the center robot 60 to be described later to the cleaning unit 30 to finish the polishing process to the cleaning unit 30 In the case of moving, the washing unit 30 is moved up and down to move the washing unit 30 to a position corresponding to the center robot 60.

The polishing unit 50 includes a grinding unit 51, a wrapping unit 52, and a polishing unit 53, which are installed on a concentric circle, and serves to polish the back surface of the wafer according to the process of each unit.

Grinding unit 51 serves to polish the back surface of the wafer when the wafer is moved from the cassette 10 by the center robot 60 to be described later.

The lapping part 52 serves to precisely polish the back surface of the wafer polished by the grinding part 51 and includes a first lapping part 52a and a second lapping part 52b to wrap the first lapping process. The division is performed by the unit 52a and the second wrapping unit 52b.

The reason why the first lapping part 52a and the second lapping part 52b is formed is that the time required for the lapping process is approximately twice as long as that of the grinding process and the polishing process. This is to move the wafer located in each part at the same time to the next process.

The polishing unit 53 serves to apply a polishing liquid to the rear surface of the wafer polished by the wrapping unit 52 to finally polish the rear surface of the wafer.

It is apparent that the grinding part 51, the lapping part 52, and the polishing part 53 are known enough to be able to purchase and use a commercially available one to those skilled in the art. The detailed configuration and operation description thereof will be omitted.

The grinding unit 51, the lapping unit 32, and the polishing unit 33 are disposed in the rotational direction of the center robot 60, which will be described later, so as to polish a pair of wafers transferred by the grip piece 62a, which will be described later. A pair of polishing apparatuses is provided vertically.

In addition, in the present exemplary embodiment, the plurality of polishing units 50 are described as being composed of the grinding unit 51, the lapping unit 52, and the polishing unit 53, but the grinding unit 51 according to the worker's implementation process. And, it may be composed of a polishing unit 53, in order to facilitate the transfer operation of the wafer by the center robot 60 to be described later by the same process time of each polishing unit 50 of the polishing unit 50 Of course, the configuration can be changed to suit the working environment.

For example, when the grinding unit 51 and the polishing unit 53 are provided, and the grinding fixed time is to be increased to 15 minutes, the grinding unit 51 is first and second like the lapping unit 52 described above. And it can be divided and installed into a third grinding unit.

As shown in FIG. 3, the center robot 60 is rotated outward from the sides of the rotating plate 61a and the rotating plate 61a rotatably installed at the centers of the concentric circles of the cassette 10 and the plurality of polishing units 50. A rotary arm 61 including five extended rotation bars 61b and a grip piece 62a rotatably installed at a distal end of the rotary arm 61 and disposed perpendicular to the rotational direction of the rotary plate 61a; And a grip part 62 including grip means 62b formed on one side of each of the five grip pieces 62a corresponding to the plurality of grinding parts 50, and the rear surface is formed by the plurality of grinding parts 50. It serves to transfer the wafer after the polishing process is completed.

Here, the grip means 62b is preferably formed as adsorption holes for vacuum suction of the wafer.

In addition, two rotation bars of the five rotation bars 61b include a support arm 61ba extending outwardly from the rotation plate 61a and a sliding portion 61bb slidably coupled to the support arm 61ba. It is configured by.

As such, two rotation bars 61b of the five rotation bars 61b are formed by the support arm 61ba and the sliding portion 61bb in order to withdraw or load the wafer loaded on the cassette 10. to be.

That is, when the wafer loaded on the cassette 10 is taken out, the sliding portion 61bb protrudes from the support arm 61ba, is inserted into the cassette 10, and is sucked by the grip means 62b which will be described later. In one state, the sliding portion 61bb may be inserted into the support arm 61ba to withdraw the wafer from the cassette 10, and the rotating bar 61b may be used to load the wafer having the polishing process completed in the cassette 10. Rotates together with the rotation of the rotating plate 61a in a state where the wafer located on the polishing unit 53 is adsorbed, and is inserted into the cassette 10 to load the wafer into the cassette 10.

As such, the center robot 60 not only shortens the transfer time of the wafer by transferring the pair of wafers to the next process but also polishes the pair of wafers simultaneously, thereby significantly reducing the wafer polishing process time and significantly improving productivity. There are features that can be made.

Specific operation description of the center robot 60 will be described in detail in the operation description of the rotary polishing apparatus for a wafer of the present invention to be described later.

The rotating unit 70 may be a conventional motor, the shaft of the motor is coupled to the center of the rotation plate 61a of the center robot 60 serves to provide a rotational force to the center robot 60.

Here, the rotation unit 70 provides a rotational force so that the center robot 60 reciprocally rotates a certain section when providing the rotational force to the center robot 60, fine control to precisely control the rotation angle of the center robot 60 It is preferable to use a conventional servomotor which can be used.

The third shankdong means 80 may be used in the usual cylinder structure, is coupled to the lower portion of the rotating part 70 serves to raise and lower the center robot 60 and the rotating part 70.

4 is a diagram illustrating an operation of the center robot to withdraw a wafer from a cassette according to an embodiment of the present invention, and FIG. 5 illustrates each part of a polishing unit receiving a wafer received from the center robot according to an embodiment of the present invention. It is a figure which shows the operation | movement seated in the.

An operation description of the rotary polishing apparatus 1 for a wafer according to an embodiment of the present invention having such a configuration will be described below with reference to FIGS. 4 to 6.

First, as shown in FIG. 4, the sliding portion 61bb of the rotary bar 61b is inserted into the cassette 10 and retracted in the state where the wafer W is adsorbed to one end of the grip piece 62a. The wafer W to be processed loaded on the wafer is taken out.

At this time, the grip piece 62a rotates 180 ° when the wafer W is seated at one end, and then repeats the drawing operation of the wafer W, which is different from the other end of the grip piece 62a of the center robot 60. One wafer W is further adsorbed.

Then, as shown in FIG. 5, in the center robot 60, with which the pair of wafers W are drawn out, the rotating plate 61a is rotated so that the rotary arm 62 is positioned in the working area of the grinding unit 51. After the pair of wafers W are seated in the working area of 51, the rotating arm 62 of the center robot 60 is separated from the working area of the grinding part 51 by rotating in reverse.

Next, when the operation of the grinding unit 51 is completed, the center robot 40 is reversely rotated so that the rotary arm 62 positioned between the grinding unit 51 and the first lapping unit 31a is connected to the grinding unit 51. The pair of wafers W seated are adsorbed and then rotated again to transfer the pair of wafers W to the work area of the first lapping part 52a which is the next process.

When the first lapping operation is completed in the first lapping part 52a by repeating the above operation, the center robot 60 transfers the pair of wafers W to the second lapping part 52b and then moves the wafer W. Secondary wrapping

Thereafter, the pair of secondary wrapped wafers W are transferred to the polishing unit 53 to perform a polishing process.

Next, the pair of wafers W completed by the polishing process are moved to the cleaning unit 30 by the center robot 60. In this case, the cleaning unit so that the center robot 60 can transfer the wafers to the cleaning unit 30. The center robot 60 is in a state in which the cassette 10 located above the 30 is lifted up by the first shandong means 20, and the washing unit 30 is raised by the second shandong means 40. The wafer W, which has been completed until the polishing process, is transferred to the cleaning unit 30 to clean contaminants contaminated during the polishing process, and dried to complete the polishing process.

In the description of the operation of the rotary polishing apparatus for wafers described in this embodiment, each process is performed step by step for better understanding of the description. However, the above-described rotary polishing apparatus for wafers of the present invention is continuously performed.

That is, when the wafer W to be processed is drawn out from the cassette 10 by the center robot 60 and then the drawn wafer W is transferred to the grinding unit 51, another rotation of the center robot 60 is performed. The arm 62 adsorbs the wafer W positioned on the grinding portion 51 and transfers the wafer W positioned on the grinding portion 51 to the first wrapping portion 52a, which is the next process, and removes the wafer W positioned on the first wrapping portion 52a. Transfer the wafer W positioned on the second wrapping portion 52b to the polishing portion 53, and transfer the wafer W positioned on the polishing portion 53 to the center robot 60. By transferring to this cleaning part 30, the grinding | polishing process of many wafer W is performed continuously.

Thus, in the present invention, the cassette 10 and the polishing unit 50 are installed concentrically, and the center robot 60 is rotated to perform the grinding process, the lapping process, and the polishing process. By continuously moving, not only the work time is significantly shortened, but each unit is installed in one device, thereby minimizing the size of the polishing apparatus, thereby reducing the required installation area.

6 is a plan view of a rotary polishing apparatus for a wafer according to another embodiment of the present invention.

6 is basically the same as the embodiment of FIGS. 1 and 5, but a pair of wafers W, which have been cleaned and dried when the process is performed in the polishing unit 50, are removed from the cleaning unit 30 to draw a cassette. By loading the wafer W on the cassette 10, the polishing process of the wafer W is continuously performed while loading the wafer W on the cassette 10.

As shown in FIG. 6, in the present embodiment, unlike the previous embodiment, the center robot 60 rotates so that the rotary arm 62 is separated from the grinding unit 51, the wrapping unit 52, and the polishing unit 53. The rotary bar 61b positioned between the grinding portion 51 and the first wrapping portion 52 formed on the rotary plate 61a, and the rotary bar 61b positioned between the polishing portion 53 and the cassette 10. The loading arm 63 is further formed extending from the one side in the direction of the cassette 10.

The loading arm 63 is preferably configured to include a support arm 63a extending outward from the rotation plate 61a and a sliding portion 63b slidably coupled to the support arm 63a.

Looking at the operation of this embodiment having the configuration as described above, when polishing the back surface of the grinding portion 51, the lapping portion 52 and the pair of wafers (W) located in the polishing portion 53, the polishing process time is 5 On the other hand, when the cleaning and drying process of the wafer W having a relatively short working time is completed, the working process time is 5 to 10 seconds, and the cleaning unit 30 and the cassette 10 are raised to load the center robot 60. When the arm 63 adsorbs the wafer W positioned on the cleaning unit 30, the cleaning unit 30 and the cassette 10 are lowered, and the cassette 10 reaches a position corresponding to the loading arm 63. The wafer W adsorbed by the loading arm 63 is loaded into the cassette 10.

Since other operations are the same as the above-described basic embodiment, the rest of the description will be omitted.

As described above, unlike the previous embodiment, another polishing process is delayed to load the wafer W into the cassette 10 by loading the wafer W, which has been cleaned and dried, into the cassette 10 during the polishing process. There is a feature that can be prevented in advance to shorten the working time, significantly improving the productivity.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims are intended to cover such modifications or changes as fall within the scope of the invention.

1 is a perspective view of a rotary polishing apparatus for a wafer according to an embodiment of the present invention;

2 is a plan view of a rotary polishing apparatus for a wafer according to an embodiment of the present invention;

3 is a perspective view of a center robot, a rotating unit, and a moving unit according to an embodiment of the present invention;

4 is a view showing an operation in which a center robot extracts a wafer from a cassette according to an embodiment of the present invention;

5 is a view showing an operation of seating the wafer received by the center robot according to an embodiment of each part of the polishing unit.

Figure 6 is a plan view of a rotary polishing apparatus for a wafer according to another embodiment of the present invention.

<Description of main drawing code>

1: Rotary Polishing Device for Wafer 10: Cassette

20: first Shanghai East means 30: washing unit

40: second shandong means 50: grinding unit

51: grinding portion 52: lapping portion

53: polishing unit 60: center robot

61: rotary arm 62: grip portion

63: loading arm 70: rotating part

80: 3rd Shanghai East Sudan

Claims (6)

At least one cassette (CASSETTE) on which the wafer to be processed and the processed wafer are loaded; A first shandong means provided on one side of the cassette to move the cassette; A plurality of polishing portions disposed concentrically with the cassette, for polishing the rear surface of the wafer withdrawn from the cassette; A rotatable arm rotatably coupled to a distal end of the rotatable arm and including a rotatable plate rotatably installed at the center of the concentric circle and a rotatable bar extending outwardly from one side of the rotatable plate corresponding to the plurality of polishing units A grip portion disposed vertically in the rotational direction at a tip end portion of the rotating bar and having grip means for gripping a wafer to be processed and a wafer to be processed at both ends, and when rotating, receiving the wafer from the transfer robot while receiving the wafer to be processed; A center robot for simultaneously moving wafers respectively positioned in the unit to the next process; A rotating unit coupled to the center of the center robot and providing rotational force to the center robot; And Is coupled to one side of the center robot, including a second shandong means for moving the center robot, Two or more of the plurality of rotating bars of the rotary bar is a rotating polishing device for a wafer comprising a support arm extending from one side of the rotating plate and a sliding portion slidably coupled from the support arm . The method of claim 1, The plurality of polishing parts A grinding unit for polishing a rear surface of the wafer drawn out from the transfer robot; A wrapping portion for regrinding the back surface of the wafer polished by the grinding portion; And And a polishing unit for applying the polishing liquid to the back surface of the wafer precisely polished by the lapping unit to finally polish the back surface of the wafer. The method of claim 2, The wrapping portion A first lapping unit for first-precision polishing the rear surface of the wafer to be processed; And And a second lapping portion for second-precision polishing the rear surface of the wafer moved from the first lapping portion. The method of claim 1, And the gripping means vacuum-adsorbs the wafer. The method of claim 1, A cleaning unit installed at a lower portion of the cassette to clean and dry a wafer having been polished; And It is installed on one side of the cleaning unit, the rotating polishing apparatus for a wafer, characterized in that it further comprises a third shandong movement means for moving the cleaning unit. The method of claim 1, The center robot In the case of performing the process in the polishing unit, a loading arm extending in the direction of the cassette from one side of the rotating plate between the grinding bar and the rotary bar located between the cassette and the polishing unit and the cassette Rotary polishing apparatus for a wafer, characterized in that it further comprises.

Images