JP2022015189A - Wafer suction device and wafer suction method - Google Patents

Abstract

To provide a wafer suction device capable of selectively sucking a portion different from a processed portion of a semiconductor wafer without performing positioning of the processed semiconductor wafer.SOLUTION: A wafer support 2 that has multiple suction ports 23 arranged independently from each other with a distance is configured so as to, when a processed wafer W is placed, perform a vacuum suction using a suction port 23 that is located at a position corresponding to the size of the processed wafer W, that is, using a corresponding suction port. The wafer suction device is configured so as to, when it is determined that any vacuum suction is not performed at the corresponding suction port, release the evacuation by returning the corresponding suction port to atmospheric pressure, and start the vacuum suction of the processed wafer W using the suction port 23 adjacent to the corresponding suction port, i.e., the neighboring suction port. With this, the processed wafers W can be selectively sucked in an outer edge portion W2 which is a portion different from the processed portion without performing the positioning of the processed wafer W.SELECTED DRAWING: Figure 4

Description

The present invention relates to a wafer adsorption device and a wafer adsorption method used for adsorption of processed semiconductor wafers.

Conventionally, in transporting or prealigning a semiconductor wafer, a method has been adopted in which a part of one surface of the semiconductor wafer is adsorbed by an arbitrary method such as vacuum adsorption or Bernoulli adsorption to temporarily fix the semiconductor wafer. Before the semiconductor wafer is processed such as device formation, one surface is a flat surface, and the adsorption site in temporary fixing is not limited.

However, when the semiconductor wafer is a wafer that has been processed in some way (hereinafter referred to as "processed wafer") such as MEMS (abbreviation of Micro Electro Mechanical Systems), in order to prevent damage to the processed portion due to adsorption. , It is necessary to limit the adsorption site. For example, when adsorbing a processed wafer, a device or the like is formed in the processed wafer, and the region constituting the semiconductor chip later is designated as an "effective chip region", and in order to prevent the wafer from being damaged, the region outside the effective chip region is adsorbed. Temporarily fix it. Examples of such a wafer adsorption device include those described in Patent Document 1.

Japanese Unexamined Patent Publication No. 2019-161241

The wafer suction device described in Patent Document 1 includes a transport section having a suction port, an elevating section, a centering section, a rotatable wafer support section having a suction port, and a sensor section, and comprises a processed wafer. Used for prealignment. In this wafer suction device, the processed wafer is conveyed to the wafer support portion without being vacuum-adsorbed via the transport portion and the elevating portion, and then the centering portion aligns the processed wafer with respect to the center position of the wafer support portion. After that, the processed wafer is rotated in a state of being vacuum-sucked by the wafer support portion, and the orientation flat or notch is detected by the sensor portion to perform prealignment. Since this wafer suction device performs vacuum suction of the processed wafer after alignment by the centering portion in prealignment and subsequent transfer, it is possible to suck the outside of the effective chip region of the processed wafer and prevent damage to the processed portion. be.

On the other hand, in recent years, in this type of wafer adsorption device, there is a need to enable adsorption retention even when the diameter size of the processed wafer changes. However, when the size of the processed wafer changes, it is necessary to increase the plane size of the alignment mechanism such as the centering portion in order to be able to handle a plurality of diameter sizes, and the size of the wafer adsorption device is increased. And can cause an increase in manufacturing costs. In addition, if the configuration does not have a mechanism for correcting the misalignment such as the alignment mechanism, if the misalignment occurs due to some factor in the transport of the processed wafer, the effective chip region of the processed wafer may be vacuum-sucked. There is.

In view of the above points, the present invention does not have a mechanism for correcting the positional deviation of the processed wafer with respect to the wafer support portion in wafer adsorption, and can handle processed wafers of different sizes, and is an effective chip among the processed wafers. The purpose is to selectively adsorb a region different from the region.

In order to achieve the above object, the wafer suction device according to claim 1 is a wafer suction device that holds a wafer by vacuum suction, has a plurality of air holes (22) independent of each other, and opens air holes. A wafer support portion (2) in which a plurality of suction ports (23) are arranged side by side at predetermined intervals, a plurality of pipes (3) for vacuuming connected to air holes different from each other, and pressure of the pipes. A pressure detection unit (4) for detecting, a flow path opening / closing unit (6) for opening / closing the flow path connected to the pipe, and a suction control unit (7) for controlling the operation of the flow path opening / closing unit are provided for suction. The control unit starts vacuuming at one of the plurality of suction ports after the wafer is placed on the wafer support, and the suction port is vacuumed based on the output signal from the pressure detection unit. If it is determined that the wafer is not adsorbed by the suction port, control is performed to switch the vacuum drawing from the suction port to another suction port adjacent to the suction port. However, the suction port that is first vacuumed by the suction control unit is the corresponding suction port at a position corresponding to the size of the wafer.

According to this, when the wafer is placed on the wafer support portion, the wafer support portion is evacuated by the corresponding suction port located at the position corresponding to the size of the wafer among the plurality of suction ports independent of each other. It is a wafer suction device that determines whether or not the wafer is vacuum sucked. Then, when it is determined that vacuum suction is not performed at the corresponding suction port, this wafer suction device controls to switch to vacuum suction by the suction port adjacent to the corresponding suction port. Therefore, when the processed wafer is placed on the wafer support portion, it is possible to selectively adsorb a region of the processed wafer different from the effective chip region which is the processed portion.

Further, by executing the control of switching the vacuum drawing in the order of the corresponding suction port at the position corresponding to the wafer size and the suction port adjacent to the corresponding suction port as needed, the size is different even if the alignment mechanism is not provided. Even if it is a wafer, the above-mentioned selective vacuum suction is possible.

The wafer suction method according to claim 8 is a wafer support portion (2) having a plurality of air holes (22) independent of each other and a plurality of suction ports (23) arranged in parallel, which are openings of the air holes. ), Which is a method of sucking the wafer placed on the wafer, and when the wafer is placed on the wafer support portion, vacuuming is performed at one of the suction ports among the plurality of suction ports, and vacuuming is performed. Detecting the pressure of the pipe (3) connected to the suction port, determining whether or not the wafer is adsorbed based on the pressure, and if it is determined that the wafer is not adsorbed, vacuuming is performed. The first suction port to be vacuumed, including switching from the suction port to another adjacent suction port, is the corresponding suction port at a position corresponding to the size of the wafer.

According to this, when vacuum suction is performed on the processed wafer placed on the wafer support portion by using one of the suction ports which are independent of each other and arranged in parallel, the suction is evacuated. It is determined whether the processed wafer is adsorbed based on the pressure of the pipe connected to the mouth. Then, evacuation is started from the corresponding suction port at the position corresponding to the size of the processed wafer, and when it is determined that the processed wafer is not adsorbed, the evacuation is switched to the adjacent suction port, so that the processed wafer is used. The vacuum is drawn in the order from the outer edge portion to the inner peripheral portion. Therefore, since the outer edge portion of the processed wafer is evacuated before the inner peripheral portion and the vacuum drawing is started from the corresponding suction port, it is not necessary to perform the alignment in consideration of the misalignment when placing the processed wafer. , It is possible to handle processed wafers of different sizes.

The reference numerals in parentheses attached to each component or the like indicate an example of the correspondence between the component or the like and the specific component or the like described in the embodiment described later.

It is a figure which shows the wafer adsorption apparatus of 1st Embodiment. It is a figure which shows the processed wafer, (a) is a plan view which shows the example which has the notch, (b) is the plan view which shows the example which has an orientation flat. It is an enlarged plan view which shows the wafer support part. It is explanatory drawing for demonstrating vacuum suction of a processed wafer in a wafer support part. It is a flowchart which shows an example of the adsorption control of the processed wafer in the wafer adsorption apparatus of 1st Embodiment. It is a figure which shows the wafer adsorption apparatus of 2nd Embodiment. It is a plan view which shows the vacuum suction of the processed wafer in 2nd Embodiment, (a) is an example by one suction port group, (b) is an example by two suction port groups. It is a top view which shows the structure of the wafer support part which concerns on the modification of 2nd Embodiment. It is a top view which shows an example of the vacuum suction of the processed wafer by the wafer support part shown in FIG. It is a top view which shows an example of the vacuum suction of the processed wafer of another size by the wafer support part shown in FIG. It is a figure which shows the wafer adsorption apparatus of 3rd Embodiment. It is an arrow view of the wafer support part seen from the XII direction of FIG. It is a top view which shows the structure of the wafer support part which concerns on the modification of 3rd Embodiment. It is a top view which shows an example of the vacuum suction of the processed wafer by the wafer support part shown in FIG. It is a top view which shows an example of the vacuum suction of the processed wafer of another size by the wafer support part shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following embodiments, the parts that are the same or equal to each other will be described with the same reference numerals.

(First Embodiment)
The wafer adsorption device 1 of the first embodiment will be described with reference to FIGS. 1 to 5.

In FIG. 1, in order to make it easier to see, the air holes 22 in the wafer support portion 2 described later are shown by broken lines while being simplified. Further, in FIGS. 3 and 4, for convenience of explanation, the arrangement direction D1 of the plurality of suction ports 23, which will be described later, is indicated by an arrow. In FIG. 4, a part of the processed wafer W is shown for easy viewing, and the outer shell of the processed wafer W and the boundary between the inner peripheral portion W1 and the outer edge portion W2 are shown by a two-dot chain line.

The wafer adsorption device 1 of the present embodiment is suitable for being used, for example, for adsorbing and holding a processed wafer at the time of transporting or prealigning a processed semiconductor wafer (processed wafer), but is limited to these applications. It's not a thing.

〔Constitution〕
As shown in FIG. 1, for example, the wafer suction device 1 of the present embodiment includes a wafer support portion 2 having a plurality of suction ports 23 independent of each other, a pipe 3, a pressure detection portion 4, a vacuum pump 5, and a flow. A road opening / closing unit 6 and a suction control unit 7 are provided. When the wafer is placed on the wafer support portion 2, the wafer suction device 1 executes vacuum suction of the wafer by one suction port 23, and releases the vacuum suction by the one suction port 23 as necessary. , It is configured to execute vacuum suction by the suction port 23 adjacent to this.

Here, the processed wafer W will be described with reference to FIG. As shown in FIG. 2A or FIG. 2B, for example, the processed wafer W has a substantially disk shape, and has an inner peripheral portion having an effective chip region (not shown) in which processing such as MEMS or an electronic device is formed. A W1 and an outer edge portion W2 which is an outer region of the inner peripheral portion W1 are provided. The processed wafer W is made of an arbitrary semiconductor material such as Si (silicon) or SiC (silicon carbide), and a notch W3 or an orientation flat W4 is formed on the outer edge portion W2.

The inner peripheral portion W1 of the processed wafer W has a distribution in thickness due to the formation of MEMS or the like, and if the back surface thereof is vacuum-sucked, it may be damaged due to its negative pressure, so that it is not suitable for vacuum suction. It is an area. The outer edge portion W2 of the processed wafer W is, for example, a region having a width of several mm from the outer shell of the processed wafer W, which has not been processed such as MEMS or electronic device formation and has a constant thickness. be.

The wafer suction device 1 of the present embodiment sequentially executes vacuum suction in a predetermined direction by a plurality of independent suction ports 23, thereby selecting an outer edge portion W2 before the inner peripheral portion W1 of the processed wafer W. The structure is such that damage to the processed wafer W can be suppressed by suction-holding the processed wafer W.

As shown in FIG. 1, for example, the wafer support portion 2 includes a base portion 21, a plurality of air holes 22 provided inside the base portion 21 and independent of each other, and a plurality of suction ports 23 which are openings of the air holes 22. Must have. The wafer support portion 2 sucks and holds the processed wafer W placed on the base 21 by vacuum suction using one of the suction ports 23 among the plurality of suction ports 23.

The base 21 is, for example, a substantially quadrangular plate-shaped member, and may be made of any member such as a metal material. As shown in FIG. 1, for example, the base portion 21 is independent of each other, and a plurality of air holes 22 connecting one surface to the other surface are formed, and a plurality of suction ports 23, which are openings thereof, are arranged in parallel with each other apart from each other. Has been done.

As shown in FIG. 3, for example, the plurality of suction ports 23 have a slit-shaped arc shape and are arranged in parallel at predetermined intervals. The plurality of suction ports 23 have substantially the same radius of curvature as the outer edge portion of the processed wafer W, for example.

Hereinafter, for the sake of simplicity of description, as shown by the double-headed arrow in FIG. 3, the direction along the direction in which the plurality of suction ports 23 are arranged is referred to as “arrangement direction D1”, and the suction port 23 of the arrangement directions D1. The direction in which the arc portion is convex may be referred to as "outside", and the opposite direction may be referred to as "inside". Further, a group in which a plurality of suction ports 23 are arranged in parallel is referred to as a "suction port group 24".

For the plurality of suction ports 23, for example, as shown in FIG. 3, the width in the arrangement direction D1 is X1, the distance between the adjacent suction ports 23 in the arrangement direction D1 is X2, and the total of X1 and X2 is processed. It is set to be equal to or less than the width of the outer edge portion W2 of the wafer W. This is to ensure that one suction port 23 fits in the outer edge portion W2 when the processed wafer W is placed on the base portion 21. The total of the width X1 of the suction port 23 and the distance X2 between the suction ports 23 is, for example, 3 mm or less, but can be appropriately changed depending on the width of the outer edge portion W2 of the processed wafer W.

From the viewpoint of improving the stability when the processed wafer W is vacuum-sucked by the wafer support portion 2, the width X1 of the suction port 23 is preferably larger than the distance X2 between the suction ports 23. From the same viewpoint, it is preferable that the direction orthogonal to the arrangement direction D1 is set as the "orthogonal direction" and the width of the suction port 23 in the orthogonal direction is larger than the width X1 in the arrangement direction D1.

The suction port group 24 has a small number of suction ports 23 so that at least one suction port 23 is located directly below the outer edge portion W2 even if the processing wafer W is displaced on the base portion 21. Also consists of three or more, preferably four or more suction ports 23.

In this specification, the case where the suction port group 24 is composed of four suction ports 23 will be described as a representative example, but the present invention is not limited to this representative example.

The plurality of air holes 22 are through holes formed in the base 21 and independent of each other, and are vacuum paths for vacuum-adsorbing the processed wafer W. The plurality of air holes 22 do not communicate with each other, and for example, different pipes 3 are connected to each other on a surface of the base 21 different from the one on which the suction port 23 is located.

The pipe 3 has, for example, a tube shape, is a tube for evacuation connecting the air hole 22 and the vacuum pump 5, and is a vacuum path at the time of vacuum suction of the processed wafer W. As shown in FIG. 1, for example, the plurality of pipes 3 are independent of each other from the air hole 22 to the flow path opening / closing portion 6, and vacuum suction of the processed wafer W via the individual air hole 22 and the suction port 23 is performed. It is possible. In each of the plurality of pipes 3, the flow path opening / closing portion 6 is connected between the air hole 22 and the vacuum pump 5. Further, the plurality of pipes 3 are connected to a pressure detecting unit 4 that detects the pressure at this time when the flow path opening / closing unit 6 is opened and communicates with the vacuum pump 5. The plurality of pipes 3 are connected, for example, between the vacuum pump 5 and the flow path opening / closing portion 6, and are connected to the vacuum pump 5 through one connected pipe 3.

It should be noted that the plurality of pipes 3 are not limited to the connection example shown in FIG. 1 as long as each of the individual air holes 22 can be evacuated in an independent state, and can be appropriately changed.

The pressure detection unit 4 is, for example, an arbitrary pressure sensor that outputs a signal corresponding to the pressure of the pipe 3. The pressure detection unit 4 is connected to, for example, an arbitrary position between the vacuum pump 5 and the flow path opening / closing unit 6 in the pipe 3, and the flow path opening / closing unit 6 is opened to communicate with the air hole 22. The pressure of the pipe 3 in the closed state is detected. The pressure detection unit 4 is connected to the suction control unit 7 by, for example, wiring or the like, and outputs a signal corresponding to the pressure of the pipe 3 to the suction control unit 7.

It should be noted that the pressure detection unit 4 only needs to be able to detect the pressure of the pipe 3 connected to the air hole 22 in which the vacuum is drawn when the vacuum is drawn in each of the air holes 22, and the air hole in the pipe 3 needs to be detected. It may be connected at an arbitrary position between the 22 and the flow path opening / closing portion 6. In this case, a plurality of pressure detection units 4 are prepared and connected to each of the pipes 3 connected to the air holes 22.

The vacuum pump 5 is an arbitrary vacuum source for sucking air, and the air hole 22 is used as a vacuum path through the pipe 3.

The flow path opening / closing unit 6 is an arbitrary opening / closing valve for opening / closing the air flow path connecting the air hole 22 and the vacuum pump 5, and is, for example, an electromagnetic valve. As shown in FIG. 1, for example, the flow path opening / closing unit 6 is connected to each of the pipes 3 connected to the air hole 22, and is also connected to the suction control unit 7 by wiring or the like. The operation of the plurality of flow path opening / closing units 6 is controlled by, for example, the suction control unit 7, and when the processed wafer W is vacuum sucked, one of them is opened and the rest are closed. As a result, any one of the plurality of pipes 3 is connected to the vacuum pump 5, and vacuum suction is performed only by the suction port 23 of the suction port group 24.

The adsorption control unit 7 is, for example, a potential control unit in which a CPU, ROM, RAM, etc. are mounted on a circuit board (not shown). When the processed wafer W is placed on the wafer support portion 2, the suction control unit 7 starts vacuum suction by a predetermined suction port 23 in the suction port group 24, and receives an output signal from the pressure detection unit 4. Based on this, it is determined whether or not the processed wafer W is vacuum-sucked. This determination can be performed, for example, by calculating the pressure of the pipe 3 or the amount of change thereof from the output signal of the pressure detection unit 4, and based on whether or not the pressure of the pipe 3 satisfies a predetermined condition. When the suction control unit 7 determines that the processed wafer W is evacuated, the suction control unit 7 maintains the vacuum suction by the suction port 23 in which the vacuum is drawn. If not, the suction control unit 7 maintains the vacuum by the suction port 23. The pull is released, and the vacuum pull by the suction port 23 adjacent to the pull is started. The suction control unit 7 repeats the above process as necessary, so that each of the plurality of suction ports 23 constituting the suction port group 24 sequentially evacuates along the arrangement direction D1. The operation of the opening / closing unit 6 is controlled. That is, the suction control unit 7 executes control for sequentially switching the suction ports 23 that evacuate the plurality of suction ports 23 according to the determination result based on the pressure.

The above is the basic configuration of the wafer adsorption device 1 of the present embodiment.

[Wafer adsorption]
The outline of the method of adsorbing the processed wafer W by the wafer adsorption device 1 will be described with reference to FIG.

As for the plurality of suction ports 23 constituting the suction port group 24, for example, as shown in FIG. 4, for distinction, the “suction port 23A” and the “suction port 23B” are sequentially arranged from the outside to the inside of the arrangement direction D1. , "Suction port 23C", "Suction port 23D", respectively.

The wafer adsorption device 1 is placed in a suction port group 24 at a position corresponding to the size of the processed wafer W when the processed wafer W is placed at a predetermined relative position with respect to the base 21 by a transport unit (not shown). Vacuum is drawn from the suction port 23 (hereinafter referred to as "corresponding suction port"). The corresponding suction port is, for example, the suction port 23A located on the outermost side in the arrangement direction D1 of the suction port 23 in the suction port group 24.

Whether or not the processed wafer W is placed on the base 21 can be determined by a known method such as detecting the processed wafer W using an arbitrary sensor such as a load sensor or an optical sensor.

Regarding the corresponding suction ports, for example, the correspondence relationship between the plurality of suction ports 23 and the flow path opening / closing unit 6, the size of the processed wafer W and the correspondence relationship between the plurality of suction ports 23 are used as data tables of the suction control unit 7. It can be controlled by storing it in a storage unit (not shown). In this case, for example, by inputting the size of the processed wafer W to the suction control unit 7 by an input device (not shown) or the like, the suction port 23 and the flow path opening / closing unit 6 corresponding to the size are determined, and the corresponding suction port is used first. Vacuuming can be started.

When the processed wafer W is placed on the base 21 of the wafer support portion 2, the wafer suction device 1 first evacuates at the corresponding suction port, and when the processed wafer W can be evacuated by this, the wafer suction device 1 first performs vacuum suction. Maintain this. On the other hand, when the processed wafer W cannot be evacuated by the corresponding suction port, the wafer suction device 1 releases the vacuum drawing at the corresponding suction port, and the suction adjacent to the corresponding suction port is inside the arrangement direction D1. Evacuation at the port 23 (hereinafter referred to as "adjacent suction port") is started. When the processed wafer W cannot be evacuated by the adjacent suction port, the wafer suction device 1 releases the vacuum at the adjacent suction port and evacuates at the suction port 23 further inside the arrangement direction D1. Start pulling.

In this way, the wafer suction device 1 sequentially evacuates toward the inside of the arrangement direction D1 starting from the corresponding suction port until the processed wafer W is evacuated. As a result, vacuum suction can be performed at the outer edge portion W2 before the inner peripheral portion W1 of the processed wafer W, and damage to the processed wafer W can be suppressed.

Specifically, for example, as shown in FIG. 4, when the processed wafer W is placed on the base 21, the wafer suction device 1 has a suction port 23A located on the outermost side of the suction port group 24 in the arrangement direction D1. Start evacuation in. After that, the wafer suction device 1 determines whether or not the processed wafer W is vacuum sucked by the suction port 23A based on the pressure or the pressure change of the pipe 3 obtained from the pressure detection unit 4.

For example, when a part or all of the suction port 23A is located outside the outer edge portion W2 of the processed wafer W as shown in FIG. 4 due to a misalignment of the processing wafer W or the like, the pipe 3 connected to the suction port 23A is connected to the pipe 3. Since it is in a state of communicating with the outside, the pressure does not drop below the specified value. In this case, the wafer suction device 1 determines that the vacuum suction of the processed wafer W by the suction port 23A has not been performed, stops the vacuum drawing at the suction port 23A, and vacuum-draws at the suction port 23B adjacent to the inside of the arrangement direction D1. To start.

Then, as shown in FIG. 4, when the entire area of the suction port 23B is located directly below the outer edge portion W2, the pipe 3 connected to the suction port 23B is in close contact with the outer edge portion W2 of the processed wafer W and is closed. As a result, the pressure drops below the specified value. In this case, the wafer suction device 1 determines that the processed wafer W has been evacuated by the suction port 23B, and continues vacuuming at the suction port 23B.

That is, the wafer adsorption device 1 performs determination based on the pressure information obtained from the pressure detection unit 4 and operation control of the flow path opening / closing unit 6 according to the determination result, from the outside to the inside of the arrangement direction D1. Vacuum is drawn in sequence toward.

As a result, vacuum drawing is sequentially performed by the suction ports 23A to 23D from the outer edge portion W2 side of the processed wafer W toward the inner peripheral portion W1, so that selective vacuum suction at the outer edge portion W2 becomes possible. Since the above-mentioned evacuation is sequentially performed, when the processed wafer W is placed on the wafer support portion 2, the outer edge portion W2 is selectively used without correcting the mounting position in consideration of the positional deviation of the processed wafer W. Vacuum adsorption is possible.

[Processing operation example]
An example of processing operation in vacuum suction of the processed wafer W by the wafer suction device 1 will be described with reference to FIG.

The wafer adsorption device 1 executes the control flow shown in FIG. 5 when a predetermined condition such as, for example, the power being turned on is satisfied. In step S01, the wafer adsorption device 1 places the processed wafer W on the base 21. The wafer adsorption device 1 may further have a transfer unit (not shown) for transporting the processed wafer W from the outside to the wafer support portion 2, and may be configured to mount the processed wafer W by itself, or may be an external transfer device. The processed wafer W may be placed by the above method.

In the subsequent step S02, the wafer suction device 1 starts evacuation at the corresponding suction port (for example, the suction port 23A) located at a position corresponding to the size of the processed wafer W. Specifically, in step S02, for example, the flow path opening / closing section 6 connected to the pipe 3 connected to the corresponding suction port by the suction control section 7 is opened, and the other flow path opening / closing section 6 is closed. The operation is controlled so that only the corresponding suction port is evacuated.

Next, in step S03, the suction control unit 7 calculates the pressure of the pipe 3 connected to the corresponding suction port based on the output signal from the pressure detection unit 4, and determines whether or not the processed wafer W is vacuum sucked. judge. For this determination condition, for example, "whether or not the detected pressure of the pipe 3 or the amount of pressure change is equal to or less than a predetermined threshold value" can be set. Then, for example, the adsorption control unit 7 advances the process to step S06 in the case of an affirmative determination in step S03, and advances the process to step S04 in the case of a negative determination in step S03.

In step S04, the suction control unit 7 closes the flow path opening / closing unit 6 corresponding to the suction port 23 that has been evacuated until then, and the suction port 23 adjacent to the suction port 23 inside the arrangement direction D1. Control is performed to open the corresponding flow path opening / closing unit 6. In other words, in step S04, the suction control unit 7 controls to switch from the vacuum drawing by a certain suction port 23 to the vacuum drawing of the suction port 23 located one inside in the arrangement direction D1.

In step S05, the suction control unit 7 determines whether or not the processed wafer W is vacuum sucked by the suction port 23 switched in step S04, as in step S03. The adsorption control unit 7 advances the process to step S06 in the case of an affirmative determination in step S05, and returns the process to step S04 in the case of a negative determination in step S05. When the process is returned to step S04 after step S05, evacuation is executed at the suction port 23 located further inside the arrangement direction D1.

In step S06, the suction control unit 7 controls to maintain evacuation at the suction port 23 when it is determined in step S03 or step S05 that the processed wafer W is evacuated. After the end of step S06, the adsorption control unit 7 ends the process.

For example, by the above processing operation, vacuum suction is performed at the outer edge portion W2 of the processed wafer W. As a result, vacuuming is sequentially performed by one suction port 23 from the outer edge portion W2 of the processed wafer W toward the inner peripheral portion W1, and the outer edge portion W2 can be selectively evacuated.

According to the present embodiment, vacuuming is sequentially performed from the outside to the inside of the arrangement direction D1 by using each of a plurality of independent suction ports 23, and the outer edge portion W2 of the processed wafer W is selectively selected. It becomes a wafer adsorption device 1 that vacuum-adsorbs to. Further, even when the processed wafer W is displaced in position, the processed wafer W is vacuum-sucked at the outer edge portion W2 before the inner peripheral portion W1 without correcting the relative position of the processed wafer W with respect to the wafer support portion 2. can do. Furthermore, by determining the corresponding suction port to be evacuated first according to the size of the processed wafer W, it is possible to selectively evacuate the region different from the effective chip region even for the processed wafer W having different sizes. ..

(Second Embodiment)
The wafer adsorption device 1 of the second embodiment will be described with reference to FIGS. 6 and 7.

In FIG. 6, a part of the base portion 21 is omitted for easy viewing, and the air holes 22 provided in the base portion 21 are shown by broken lines as in FIG. 1. In FIGS. 7 (a) and 7 (b), in order to make it easier to see, the outer shell of the processed wafer W when the processed wafer W is placed on the base 21, and the boundary between the inner peripheral portion W1 and the outer edge portion W2 are two. It is shown by a dotted line.

In the wafer adsorption device 1 of the present embodiment, for example, as shown in FIG. 6, the wafer support portion 2 further includes a transfer arm 25, and as shown in FIG. 7, the base portion 21 has a rectangular plate shape. It differs from the form. In this embodiment, the above differences will be mainly described.

In the wafer adsorption device 1 of the present embodiment, the wafer support portion 2 has a transfer arm 25, and is configured as a transfer device for the processed wafer W.

The transfer arm 25 is connected to, for example, a power source (not shown) so that the base 21 can be moved. The transport arm 25 is configured to allow, for example, the base 21 to be translated horizontally, vertically, or both. The transfer arm 25 is operated, for example, by operating a power source (not shown) by the suction control unit 7 or another control unit.

The term "horizontal movement" as used herein means, for example, moving the processed wafer W in the left-right direction, that is, along the plane direction of the base 21. "Vertical movement" means, for example, moving the processed wafer W in the vertical direction, that is, along the thickness direction of the base 21.

In the present embodiment, the base portion 21 has a rectangular plate shape, for example, as shown in FIG. 7A, and has a configuration in which a suction port group 24 is provided at at least one end in the longitudinal direction thereof. When the processed wafer W is placed on the base 21, the wafer suction device 1 executes the same control as in the first embodiment, and any one of the suction ports 23A to 23D constituting the suction port group 24 After vacuum suction of the processed wafer W, the processed wafer W is conveyed.

As shown in FIG. 7B, for example, the base portion 21 may have a configuration in which one suction port group 24 is provided at both ends in the longitudinal direction. In this case, the suction port group 24A on one end side is, for example, in the arrangement direction thereof, with one end of the end portion in the longitudinal direction of the base portion 21 opposite to the transport arm 25 and the other end end on the transport arm 25 side. The outside of D1 is arranged in the opposite direction to that of the suction port group 24B on the other end side. That is, the suction port group 24A is arranged so that the convex side in the arc portion of the plurality of suction ports 23 faces one end side of the base portion 21, and the suction port group 24B has the convex side in the arc portion of the plurality of suction ports 23 as the base portion 21. It is arranged so as to face the other end side of the.

The suction port groups 24A and 24B are paired, and each of the suction ports 23 (suction port 23B in the example of FIG. 7B) can be used for vacuum suction at the outer edge portion W2 of the processed wafer W. Are arranged at a predetermined distance. For example, although not limited, the suction port 23D of the suction port group 24A and the suction port 23D of the suction port group 24B are arranged so that the distance in the longitudinal direction of the base 21 is about 1 cm smaller than the diameter of the processed wafer W. To.

Further, when the base portion 21 is configured to include the suction port groups 24A and 24B, when the suction control unit 7 determines the suction port 23 for vacuum sucking the processed wafer W in one of the suction port groups 24A and 24B, The suction position in the other suction port group 24 may be determined corresponding to the suction port 23. For example, as shown in FIG. 7B, when the processed wafer W is adsorbed at the suction port 23B of the suction port group 24A, the suction control unit 7 sucks the suction port 23B at the time of evacuation in the suction port group 24B. May be first evacuated with the corresponding suction port. For example, data in which the suction ports 23 of the paired suction port groups 24 are associated with each other is created, the data is stored in a storage unit (not shown) of the suction control unit 7, and suction holding is performed by one of the suction port groups 24. This can be done by processing such as reading the data when the suction port 23 to be used is determined. Of course, in each suction port group 24, vacuuming may be sequentially executed from the outside to the inside in the arrangement direction of the plurality of suction ports 23.

According to the present embodiment, the wafer adsorption device 1 is capable of transporting the processed wafer W while obtaining the effects of the first embodiment.

(Modified example of the second embodiment)
As shown in FIG. 8, for example, the wafer suction device 1 of the second embodiment may have a configuration in which the wafer support portion 2 includes a suction port group 24 having three or more suction ports 24. In this case, in the wafer support portion 2, for example, the suction port group 24A is arranged at one end of the base portion 21, and a plurality of suction port groups 24B to 24D are arranged at the other end side at a predetermined distance from the suction port group 24A. It is said to be configured.

The suction port group 24A is arranged so that the convex side of the arc shape faces one end side of the base portion 21. On the other hand, the suction port groups 24B to 24D are paired with the suction port group 24A, respectively, and are arranged so that the convex side of the arc shape faces the other end side of the base portion 21.

Specifically, for example, as shown in FIG. 9, when a processed wafer W of a certain size is placed, the wafer support portion 2 pairs the suction port groups 24A and 24B to hold the processed wafer W by suction. Execute. Further, for example, as shown in FIG. 10, when a processed wafer W having a larger size is placed, the wafer support portion 2 executes suction holding of the processed wafer W with the suction port groups 24A and 24C as a pair. .. As described above, the wafer support portion 2 is capable of vacuum suction of the processed wafer W by the suction port group 24A and another suction port group 24 paired with the suction port group 24A according to the size of the processed wafer W.

The distance between the suction port group 24A and the other suction port groups 24B to 24D is appropriately set according to the size of the processed wafer W (for example, the diameter is 5 inches, 6 inches, 8 inches, 12 inches, etc.). Inch. Further, in the above description, an example in which the wafer support portion 2 includes three other suction port groups 24 paired with the suction port group 24A has been described, but the present invention is not limited to this, and the other suction port group 24 is not limited to this. The number, arrangement, etc. can be changed as appropriate.

According to this modification, while the effect of the first embodiment is obtained, a plurality of types of processed wafers W having different sizes can be more reliably adsorbed and held, and the processed wafer W can be conveyed in this state. It becomes the device 1.

(Third Embodiment)
The wafer adsorption device 1 of the third embodiment will be described with reference to FIGS. 11 and 12.

In FIG. 11, only a part of the plurality of pipes 3 and the flow path opening / closing section 6 is shown for easy viewing, and the other piping 3 and the flow path opening / closing section 6 are omitted. In FIG. 12, for easy viewing, the outer shell of the processed wafer W when the processed wafer W is placed on the base portion 21 and the boundary between the inner peripheral portion W1 and the outer edge portion W2 are shown by a two-dot chain line. Further, in FIG. 12, the outer shell of the rotation mechanism 26, which is invisible from one side of the base 21 on which the suction port group 24 is formed, is shown by a broken line.

As shown in FIG. 11, for example, the wafer adsorption device 1 of the present embodiment includes a rotation mechanism 26 for the wafer support portion 2 to rotate the base portion 21, and can rotate the base portion 21 in a state where the processed wafer W is vacuum-adsorbed. It differs from the first embodiment in that it has a different configuration. In this embodiment, the above differences will be mainly described.

In the wafer adsorption device 1 of the present embodiment, the wafer support portion 2 has a rotation mechanism 26, and is configured as a prealignment device capable of prealigning the processed wafer W. The wafer suction device 1 includes, for example, a sensor unit (not shown) that detects a notch W3 of the processed wafer W and an orientation flat W4, and can perform prealignment after vacuum suctioning the processed wafer W. Since the wafer prealignment is known, detailed description thereof will be omitted in the present specification.

In the present embodiment, the wafer support portion 2 is formed with one suction port group 24 at both ends of the base portion 21 in the longitudinal direction, as shown in FIG. 12, for example. The suction port groups 24A and 24B are paired, and the convex sides of the arc shape face each other and are symmetrically arranged with respect to the center 21a of the base portion 21. The wafer support portion 2 has a configuration in which the outer edge portion W2 of the processed wafer W is sucked and held by the paired suction port groups 24A and 24B under the same vacuum suction control as in each of the above embodiments.

The rotation mechanism 26 is, for example, an arbitrary mechanism for rotating the base portion 21 within a predetermined range about a normal line passing through the center 21a of the base portion 21. As shown in FIG. 11, for example, the rotation mechanism 26 is attached to a surface of the base 21 opposite to the one on which the suction port group 24 is formed, and is connected to a power source (not shown). The rotation mechanism 26 serves to rotate the processed wafer W for prealignment after the processed wafer W is vacuum-sucked by the two suction port groups 24. The rotation mechanism 26 is controlled to rotate by the suction control unit 7 or another control unit (not shown).

According to the present embodiment, the wafer adsorption device 1 is capable of prealigning the processed wafer W while obtaining the effects of the first embodiment.

(Modified example of the third embodiment)
As shown in FIG. 13, for example, the wafer suction device 1 of the third embodiment may have a configuration in which a plurality of suction port groups 24 are provided at both ends of the base 21 in the longitudinal direction.

In this modification, as shown in FIG. 13, in order to distinguish the plurality of suction port groups 24, the two suction port groups 24 closest to the center 21a of the base 21 among the plurality of suction port groups 24 are referred to as “suction port groups 24”. It is called "24A". Further, the suction port group 24 adjacent to the outside of the suction port group 24A is referred to as "suction port group 24B", and the suction port group 24 adjacent to the outside of the suction port group 24B is referred to as "suction port group 24C".

As shown in FIGS. 14 and 15, for example, the wafer support portion 2 has two suction port groups 24A, 24B, and 24C as a pair, and holds a plurality of types of processed wafers W having different sizes by vacuum suction. It is configured to be. As described above, the wafer support portion 2 may have a configuration having two or more pairs of suction port groups 24, and the number and arrangement of the paired suction port groups 24 can be appropriately changed.

According to this modification, a wafer adsorption device capable of pre-aligning the processed wafer W while more reliably adsorbing and holding a plurality of types of processed wafers W of different sizes while obtaining the effect of the first embodiment. It becomes 1.

(Other embodiments)
Although the present invention has been described in accordance with the examples, it is understood that the present invention is not limited to the examples and structures. The present invention also includes various modifications and variations within a uniform range. In addition, various combinations and forms, as well as other combinations and forms including only one element thereof, more or less, are also within the scope and scope of the present invention.

For example, in the third embodiment, when a plurality of suction port groups 24 are formed on the base portion 21 of the wafer support portion 2, the plurality of paired suction port groups 24 are relative to the center position of the base portion 21. The example in which they are arranged symmetrically has been described, but the present invention is not limited to this. Specifically, the pair of suction port groups 24 may be arranged so as to be able to vacuum suck the processed wafer W, are orthogonal to the longitudinal direction of the base 21, and are symmetrical with respect to the straight line passing through the center 21a. The arrangement is not limited to the above, and may be a symmetrical arrangement that is point-symmetrical with respect to the center 21a.

2 Wafer support 22 Air hole 23 Suction port 24 Suction port group 25 Conveyance arm 26 Rotation mechanism 3 Piping 4 Pressure detection unit 6 Flow path opening / closing unit 7 Suction control unit

Claims (10)

A wafer suction device that holds a wafer by vacuum suction.
A wafer support portion (2) having a plurality of air holes (22) independent of each other and having a plurality of suction ports (23) which are openings of the air holes arranged side by side at predetermined intervals.
A plurality of pipes (3) for evacuation connected to the air holes that are different from each other, and
A pressure detection unit (4) that detects the pressure of the pipe, and
A flow path opening / closing section (6) that opens / closes the flow path connected to the pipe, and
A suction control unit (7) that controls the operation of the flow path opening / closing unit is provided.
The suction control unit starts evacuation at the suction port of one of the plurality of suction ports after the wafer is placed on the wafer support portion, and is evacuated based on an output signal from the pressure detection unit. It is determined whether or not the wafer is sucked by the suction port to which the evacuation port is being pulled, and if it is determined that the wafer is not sucked by the suction port, vacuum pulling is performed from the suction port to the suction port. Control to switch to the other suction port adjacent to the
The wafer suction device, in which the suction port that is first evacuated by the suction control unit is a corresponding suction port at a position corresponding to the size of the wafer. The corresponding suction port is the suction port located closest to one end of the wafer support portion in the longitudinal direction among the plurality of suction ports.
When the adsorption control unit determines that the wafer is not adsorbed, the vacuum is set so as to go from one end of the wafer support unit to the other end in the opposite direction until it is determined that the wafer is adsorbed. The wafer suction device according to claim 1, wherein the control for sequentially switching the suction ports for pulling is executed. The wafer suction device according to claim 1 or 2, further comprising a transfer arm (25) for moving the wafer support portion. The wafer adsorption device according to claim 1 or 2, further comprising a rotation mechanism (26) for rotating the wafer support portion. The group consisting of the plurality of suction ports is referred to as a suction port group (24), and the wafer support portions are arranged apart from each other and include a plurality of pairing of the suction port groups.
When the suction control unit determines that the wafer is sucked in one of the two suction port groups in a pair, the suction control unit is one of the suction port groups in the other suction port group. The wafer suction device according to any one of claims 1 to 4, wherein the vacuum drawing is started from the predetermined suction port corresponding to the suction port to which the vacuum is drawn. The wafer suction device according to claim 5, wherein at least one of the plurality of suction port groups is arranged on at least one end side in the longitudinal direction of the wafer support portion. The wafer suction device according to claim 5 or 6, wherein the plurality of suction ports are arranged symmetrically with respect to the center position of the wafer support portion. A method for sucking a wafer mounted on a wafer support portion (2) having a plurality of independent air holes (22) and openings of the air holes and having a plurality of suction ports (23) arranged in parallel. And
When the wafer is placed on the wafer support portion, vacuuming is performed at the suction port of one of the plurality of suction ports.
Detecting the pressure of the pipe (3) connected to the suction port that is evacuated, and
Determining whether or not the wafer is adsorbed based on the pressure,
When it is determined that the wafer is not adsorbed, the vacuuming includes switching from the suction port to another adjacent suction port.
A method for sucking a wafer, wherein the suction port to be evacuated first is a corresponding suction port at a position corresponding to the size of the wafer. In switching to the other suction port, the suction port for evacuating is sequentially drawn from one end of the wafer support portion toward the other end in the opposite direction until it is determined that the wafer is sucked. The wafer adsorption method according to claim 8, which is switched. As a suction port group (24) which is a group consisting of a plurality of the suction ports, the wafer support portions are arranged apart from each other and include a plurality of the suction port groups forming a pair.
When it is determined that the wafer is adsorbed in one of the two suction port groups in a pair, the other suction port group is evacuated in one of the suction port groups. The method for sucking a wafer according to claim 8 or 9, further comprising initiating evacuation starting from the predetermined suction port corresponding to the suction port.

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