JP2010283280A - Position recognition device and position recognition method, and alignment device and alignment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent hanging and flapping of an outer peripheral part protruding from an outer edge of a support surface supporting a tabular member when detecting the outer peripheral part of the tabular member to perform position recognition and alignment. <P>SOLUTION: An alignment device 10 includes: a support means 11 including a support surface 11A supporting a part inside an outer edge of a wafer W; a detection means 12 which detects the outer edge of the wafer W; a rotation means 15 which relatively rotates the wafer W and the detection means 12; a movement means 17 which moves the support means 11 in directions of two orthogonal axes; a control means which controls these means and includes a function of calculating a prescribed reference position of the wafer W based on detection data to locate the prescribed reference position in a fixed position; and a contactless support means 14 which supports an outer edge-side part W1 of the wafer, which protrudes from the outer edge of the support surface 11A, with a fixed distance apart from the detection means 12 without contacting. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a position recognition apparatus, a position recognition method, and an alignment apparatus and alignment method. For example, a position recognition apparatus and a position recognition method suitable for positioning a plate-like member such as a semiconductor wafer, and alignment. The present invention relates to an apparatus and an alignment method.

A plate-like member such as a semiconductor wafer (hereinafter simply referred to as “wafer”) is positioned at a predetermined reference position such as an orientation flat or V notch indicating a crystal orientation or a wafer center position when performing various processes. Positioning (alignment) is performed.
As an apparatus for performing such alignment, for example, as disclosed in Patent Document 1, a wafer chuck having a suction support surface that supports the wafer inside the outer edge of the wafer is used, and the wafer is placed in a plane. A configuration is known in which the outer edge is detected by rotation, and is moved and positioned in two orthogonal directions in the plane, that is, in the X and Y axis directions.

JP-A-8-8328

However, in the configuration disclosed in Patent Document 1, when positioning an extremely thin wafer, as shown by a two-dot chain line in FIG. 3, the wafer outer edge side portion protruding outward from the support surface of the wafer chuck. When a wafer with the outer edge side portion partially drooped is rotated, the outer edge side portion of the wafer appears to flutter, and the linear sensor is positioned accurately on the outer edge of the wafer. There is an inconvenience that the recognition cannot be performed and the subsequent positioning is distorted. In addition, in the case of a wafer having an adhesive sheet affixed on one surface and ground to a thickness of several tens of μm, the outer edge side portion is wavy because warpage occurs due to the elastic restoring force of the adhesive sheet. There is an inconvenience that it is deformed like the above, and the fluttering becomes more remarkable.
In such a case, if a wafer chuck having a support surface capable of adsorbing the entire surface of the wafer is employed, it is possible to eliminate the inconvenience of drooping and fluttering of the outer edge of the wafer, but detection for detecting the outer edge of the wafer. The sensor of the means cannot distinguish the boundary between the wafer and the wafer chuck, resulting in another inconvenience that accurate positioning is impossible.

[Object of invention]
The present invention has been devised by paying attention to such inconveniences, and the object thereof is to use a support means having a support surface for supporting the plate-like member inside the outer edge of the plate-like member. Even in such a case, a position recognition device and a position recognition method capable of accurately recognizing the position of the plate-like member by avoiding drooping or flapping of the outer edge portion of the plate-like member protruding from the support surface. It is to provide.

  Another object of the present invention is to provide an alignment apparatus and an alignment method capable of recognizing the outer edge of a plate member and accurately positioning a predetermined reference position of the plate member at a fixed position.

  In order to achieve the above object, a position recognition device according to the present invention includes a support means including a support surface for supporting the plate-like member inside an outer edge of the plate-like member, and a plate-like member protruding from the support surface. Non-contact support means which is disposed relatively to a position away from the outer edge side portion and forms a negative pressure region with the outer edge side portion of the plate-like member by ejecting fluid along the surface of the plate-like member. And detecting means for detecting an outer edge of the plate-like member and outputting detection data thereof, and the non-contact support means sucks the force of the fluid ejected to the plate-like member and the negative pressure region. At the position where the force is suspended, the outer edge side portion of the plate-like member is supported in a non-contact manner, and the outer edge of the plate-like member is kept at a position separated from the detection means by a certain distance.

  In the present invention, a configuration including a rotating means for relatively rotating the plate-like member and the detecting means within a plane is adopted.

  Further, the alignment apparatus according to the present invention is separated from a support means including a support surface for supporting the plate-like member on the inner side of the outer edge of the plate-like member, and an outer edge side portion of the plate-like member protruding from the support surface. A non-contact support means that forms a negative pressure region with an outer edge side portion of the plate-like member by being arranged relative to the position and ejecting a fluid along the surface of the plate-like member; and the plate-like member Rotating means that relatively rotates the detection means in a plane, detection means for detecting an outer edge of the plate-like member and outputting detection data thereof, and movement of the plate-like member in two orthogonal axes in the plane A control unit including a moving unit and a function of controlling each of the units, calculating a predetermined reference position of the plate-like member based on the detection data, and positioning the predetermined reference position at a fixed position; The non-contact support means is provided on the plate member. The outer edge side portion of the plate-like member is supported in a non-contact manner at a position where the force of the fluid ejected and the force sucked by the negative pressure region are suspended, and the outer edge of the plate-like member is fixed distance from the detection means It is configured to keep it at a distance.

  Furthermore, the position recognition method according to the present invention includes a step of supporting the plate member inside the outer edge of the plate member, and a surface of the plate member from a position away from the outer edge side portion of the plate member. A step of forming a negative pressure region between the plate-like member and the outer edge side portion of the plate-like member, and a force of the fluid ejected to the plate-like member and a force sucked by the negative pressure region And a non-contact support of the outer edge side portion of the plate-like member at a position where the two are suspended, and maintaining the outer edge of the plate-like member at a position separated from the detection means by a certain distance, and the outer edge of the plate-like member And a step of detecting and outputting the detected data.

  The alignment method according to the present invention includes a step of supporting the plate member inside the outer edge of the plate member, and a surface of the plate member from a position away from the outer edge side portion of the plate member. A step of forming a negative pressure region with the outer edge side portion of the plate-like member by ejecting fluid, and a force of the fluid ejected to the plate-like member and a force sucked by the negative pressure region A step of supporting the outer edge side portion of the plate-like member in a non-contact manner at a position where the plate-like members are suspended, and maintaining the outer edge of the plate-like member at a position spaced apart from the detection means by the plate-like member and the detection means. A step of relatively rotating in a plane; a step of detecting an outer edge of the plate-like member by the detection means; outputting detection data; and calculating a predetermined reference position of the plate-like member based on the detection data; Including a step of positioning the predetermined reference position at a fixed position. To have.

  According to the present invention, when position recognition or alignment is performed, even when the plate member is supported inside the outer edge of the plate member, the force of the ejected fluid and the force sucked by the negative pressure region Since the outer edge portion of the plate-like member can be supported in a non-contact manner at a position where the plate members are suspended, the outer edge portion of the plate-like member does not move away from or approaches the detection means. It can be kept in a separated position. Thereby, it can avoid that the outer edge part of a plate-shaped member hangs down or flutters, and can perform exact position recognition and alignment. In addition, since there is nothing (such as the wafer chuck of the conventional example) that is located in contact with the outer edge of the plate-like member, the detection means cannot distinguish the boundary between the plate-like member and another, and the accurate The inconvenience that position recognition and alignment cannot be performed can be solved.

The partial cross section front view of the alignment apparatus which concerns on embodiment. The top view of FIG. FIG. 2 is a detailed view of part a in FIG. 1. FIG. 4 is a diagram illustrating the principle for recognizing the center position of a wafer. The partial top view which shows a modification.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 and 2, the alignment apparatus 10 includes a support means 11 including a support surface 11A that supports the wafer W inside the outer edge of a wafer W (diameter 300 mm, thickness 100 μm) as a plate-like member, and the wafer W. Detecting means 12 for detecting the outer edge of the wafer W and outputting the detected data, non-contact support means 14 disposed relatively away from the outer edge portion W1 of the wafer W protruding from the support surface 11A, the wafer W and the detecting means. Rotating means 15 for relatively rotating 12 in the plane, moving means 17 for moving the wafer W in two orthogonal axes in the plane, and control means (not shown) including a function for controlling these means. Has been. The support means 11, the detection means 12, the non-contact support means 14 and the rotation means 15 constitute a position recognition device.

  The support means 11 includes an inner table 20 having a support surface 11 </ b> A (diameter 200 mm) and an outer table 22 having a recess 21 for receiving the inner table 20. The inner table 20 is provided in a substantially circular shape in plan view, and is connected to a decompression pump (not shown) so that the support surface 11A (upper surface in FIG. 1) acts as a suction support surface. The outer table 22 includes an annular peripheral wall 25 surrounding the inner table 20 and a bottom wall 26 located at the lower end of the peripheral wall 25. As shown in FIG. The non-contact support means 14 is arrange | positioned at four places spaced apart by 90 degree | times of the circumferential direction of the surrounding wall 25. FIG.

  Although the detection means 12 is not particularly limited, in the present embodiment, it is constituted by a CCD camera. The detection means 12 is disposed relative to one non-contact support means 14 at a position that is a predetermined distance above the upper surface of the peripheral wall 25 in the outer table 22, whereby the outer edge of the wafer W can be detected. Yes. The detection data of the detection means 12 is output to the control means.

  As shown in FIG. 3, the non-contact support means 14 is provided in a substantially circular shape in plan view, and a substantially conical conical recess 30 </ b> A that penetrates the lower surface side and the upper surface side in FIG. 3 and is similar to a funnel is formed. And a substantially cone-shaped conical member 33 similar to a funnel that is combined with the main body 30 and is disposed at a predetermined interval from the conical recess 30A to form an annular passage 32 in sectional view. And a supply path 34 that is formed in the outer table 22 and communicates with the passage 32, and a pressure pump (not shown) that supplies air G as a fluid to the supply path 34. The passage 32 forms an annular spout 32A at its upper end. The conical member 33 is supported on the main body 30 by a support member (not shown) that does not fully close the passage 32. With such a configuration, when the air G is supplied to the passage 32, the air G ejected from the ejection port 32A flows along the surface of the wafer W. A negative pressure region A is formed between the lower surface of the outer edge side portion W1. Then, the outer edge side portion W1 of the wafer W is supported in a non-contact manner at a position where the force of the air G ejected to the wafer W and the force sucked by the negative pressure region A are suspended, and the outer edge of the wafer W is It can be kept at a position away from the detection means 12 by a certain distance. Thus, the outer edge side portion W1 of the wafer W, particularly, the portion from the center position of the wafer W to the outer edge located below the detecting means 12 can be kept in the same plane without drooping or wobbling. And accurate position recognition can be performed. In the case of such a non-contact support means 14, the wafer W is supported while being restricted from moving in the direction in which the wafer W contacts and separates from the non-contact support means 14 (Z-axis direction). The movement in the direction perpendicular to the direction of contact with and away from (a direction parallel to the XY plane) is not restricted. In addition, although the non-contact support means 14 used by this embodiment employ | adopts the non-contact conveyance machine made from Koganei Co., Ltd., the illustrated structure explains the principle which forms the non-contact area | region A easily. In order to do this, it is shown equivalently.

  The rotating means 15 is connected to the lower surface side of the inner table 20, and is constituted by a motor M1 that rotates the inner table 20 in a plane. The motor M1 is fixed to the output shaft 40A of the linear motion motor 40 fixed to the bottom wall 26, and the height of the inner table 20 can be adjusted.

  The moving means 17 is constituted by an XY table 42 that supports the supporting means 11 so as to be movable in two orthogonal axes, that is, in the X and Y directions in the drawing. Lifting means such as a linear motor may be provided between the XY table 42 and the support means 11, and in this case, the overall height of the support means 11 can be adjusted.

  Next, a method for recognizing the position of the wafer W will be described.

The wafer W is mounted on the support surface 11A of the inner table 20 via a transfer means (for example, a robot arm) not shown. When the mounting of the wafer W is confirmed by a sensor (not shown), the wafer W is sucked and supported by the support surface 11A. The inner table 20 is adjusted by the linear motion motor 40 so that the distance between the lower surface of the wafer W and the upper surface of the non-contact support means 14 is a predetermined distance.
When the wafer W is adsorbed and supported, air G is supplied to the supply path 34 from a pressure pump (original pressure 0.49 Mpa) (not shown), and the air G ejected from the ejection port 32A through the path 32 is the surface of the wafer W. Flowing along. Thereby, the movement of the wafer W in the direction of rotation is not restricted, and the movement of the wafer W in the direction in contact with and away from the detection means 12 is restricted and supported in a non-contact manner.
In the state as described above, the detection unit 12 detects a plurality of outer edges of the wafer W, and outputs the detection data to the control unit as coordinate positions in the XY plane.
For example, as shown in FIG. 4, the control means obtains at least two straight lines (strings) L that connect two points out of a plurality of locations on the outer edge of the detected wafer W, and obtains a vertical bisection of the straight lines (strings) L. The center point Wc of the wafer W (predetermined reference position of the wafer W) is recognized as the coordinate position in the XY plane at the intersection of the dividing lines. Note that a straight line (string) L connecting two points on the outer edge of the wafer W may be obtained at a position where the wafer W is rotated by a predetermined angle by the rotating means 15.
Thereafter, for example, the control unit outputs the center position Wc of the wafer W to a transfer unit (not shown). The transfer means that has received this output may support the wafer W with reference to the center position Wc of the wafer W and supply it to another apparatus.

  Next, an alignment method for the wafer W will be described.

The wafer W is placed on the support surface 11A of the inner table 20 via a transfer means (not shown). When the mounting of the wafer W is confirmed by a sensor (not shown), the wafer W is sucked and supported by the support surface 11A. The inner table 20 is adjusted by the linear motion motor 40 so that the distance between the lower surface of the wafer W and the upper surface of the non-contact support means 14 is a predetermined distance.
When the wafer W is adsorbed and supported, air G is supplied to the supply path 34 from a pressure pump (original pressure 0.49 Mpa) (not shown), and the air G ejected from the ejection port 32A through the path 32 is the surface of the wafer W. Flowing along. Thereby, the movement of the wafer W in the direction of rotation is not restricted, and the movement of the wafer W in the direction in contact with and away from the detection means 12 is restricted and supported in a non-contact manner.
In the state as described above, the motor W1 rotates at a predetermined rotation speed, thereby rotating the wafer W relatively. The rotational speed of the motor M1 is set so that the outer edge of the wafer W having a diameter of 300 mm rotates at a speed of 30 mm per second. Then, the detection means 12 detects a plurality of positions of the outer edge of the wafer W, and outputs the detected data to the control means as coordinate positions in the XY plane.
Based on the rotation position (rotation angle) of the motor M1 and the detection data from the detection unit 12, the control unit controls the V notch N of the wafer W (a predetermined reference position of the wafer W) and the center position Wc of the wafer W (of the wafer W). (Predetermined reference position) is stored as a coordinate position in the XY plane.
Thereafter, the control means, for example, as shown in FIG. 2, is arranged so that the V notch N is positioned on a straight line passing through the center position Wc of the wafer W and parallel to the Y-axis direction, that is, at a fixed position. The XY table 42 is driven so that the center position Wc of the wafer W is positioned at the imaginary fixed position Ic in the XY plane. Thereafter, for example, a transfer means (not shown) supports the wafer W with reference to the imaginary fixed position Ic (at this time, the V notch N is located on a straight line passing through the imaginary fixed position Ic and parallel to the Y-axis direction). Will be supplied to other devices.

  Therefore, according to such an embodiment, even a plate-like member ground to a thickness of several tens of μm, such as the wafer W, can accurately recognize the position and rotate the wafer W during alignment. Even if it carries out, the effect that the alignment of the wafer W can be performed with high precision based on the positional information of the plate-shaped member recognized without the wafer W flapping is acquired.

As described above, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this.
In other words, the present invention has been illustrated and described mainly with respect to specific embodiments, but without departing from the scope of the technical idea and object of the present invention, the shape, position, or With respect to the arrangement and the like, those skilled in the art can make various changes as necessary.
Therefore, the description limited to the shape disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded one part or all part is included in this invention.

  For example, the above-described embodiment is merely illustrative. That is, the present invention can be applied to the case where the outer edge side portion hangs down or flutters when performing position recognition or alignment of the plate-like member with the outer edge side portion protruding from the outer edge of the support surface. Various conditions such as the size of the plate-like member, the size of the support surface, the rotation speed of the plate-like member, and the supply pressure of air for forming the negative pressure region should be arbitrarily determined (set). Can do.

  Further, the plate-like member is not limited to the semiconductor wafer W, and other plate-like members such as a glass plate, a steel plate, or a resin plate can also be targeted. The semiconductor wafer can be a silicon wafer or a compound wafer. It may be.

Further, an area sensor, a line sensor, or the like can be used as the detection unit 12.
Further, the non-contact support means 14 is not limited to the one in the embodiment, and the outer edge portion of the plate-like member is not at the position where the force of the fluid to be ejected and the force to be sucked by the negative pressure region are suspended. Any device that supports the contact and maintains the outer edge of the plate-like member at a certain distance from the detection means is sufficient.

  Furthermore, the rotation unit may be configured to rotate at least one of the wafer W and the detection unit 12 in a plane.

  In the above embodiment, the detection means 12 is disposed relative to one non-contact support means 14, but the detection means 12 is not contacted so as to be sandwiched between the upstream side and the downstream side in the rotation direction of the wafer W as shown in FIG. The support means 14 may be disposed relatively.

DESCRIPTION OF SYMBOLS 10 Alignment apparatus 11 Support means 11A Support surface 12 Detection means 14 Non-contact support means 15 Rotation means 17 Movement means A Negative pressure area G Air (fluid)
W Semiconductor wafer (plate member)
W1 outer edge

Claims (5)

A support means including a support surface for supporting the plate-like member inside the outer edge of the plate-like member;
Relatively arranged at a position away from the outer edge side portion of the plate-like member protruding from the support surface, and by ejecting fluid along the surface of the plate-like member, between the outer edge side portion of the plate-like member Non-contact support means forming a negative pressure region;
Detecting means for detecting an outer edge of the plate-like member and outputting the detection data;
The non-contact support means supports the outer edge side portion of the plate-like member in a non-contact manner at a position where the force of the fluid ejected to the plate-like member and the force sucked by the negative pressure region are suspended. A position recognition device, characterized in that the outer edge of the plate-like member is kept at a position spaced apart from the detection means by a certain distance.   The position recognition apparatus according to claim 1, further comprising a rotation unit that relatively rotates the plate-like member and the detection unit within a plane. A support means including a support surface for supporting the plate-like member inside the outer edge of the plate-like member;
Relatively arranged at a position away from the outer edge side portion of the plate-like member protruding from the support surface, and by ejecting fluid along the surface of the plate-like member, between the outer edge side portion of the plate-like member Non-contact support means forming a negative pressure region;
A rotating means for relatively rotating the plate-like member and the detecting means in a plane;
Detecting means for detecting an outer edge of the plate-like member and outputting the detection data;
A moving means for moving the plate-like member in a biaxial direction in a plane;
Control means including a function of controlling each of the means, calculating a predetermined reference position of the plate-like member based on the detection data, and positioning the predetermined reference position at a fixed position;
The non-contact support means supports the outer edge side portion of the plate-like member in a non-contact manner at a position where the force of the fluid ejected to the plate-like member and the force sucked by the negative pressure region are suspended. An alignment apparatus, characterized in that the outer edge of the plate-like member is maintained at a position spaced apart from the detection means by a certain distance. A step of supporting the plate member inside the outer edge of the plate member;
Forming a negative pressure region with the outer edge side portion of the plate member by ejecting fluid along the surface of the plate member from a position away from the outer edge side portion of the plate member;
The outer edge side portion of the plate member is supported in a non-contact manner at a position where the force of the fluid ejected to the plate member and the force sucked by the negative pressure region are suspended, and the outer edge of the plate member is Maintaining the position at a distance from the detection means;
And a step of detecting the outer edge of the plate-like member and outputting the detected data. A step of supporting the plate member inside the outer edge of the plate member;
Forming a negative pressure region with the outer edge side portion of the plate member by ejecting fluid along the surface of the plate member from a position away from the outer edge side portion of the plate member;
The outer edge side portion of the plate-like member is supported in a non-contact manner and the outer edge of the plate-like member is detected at a position where the force of the fluid ejected to the plate-like member and the force sucked by the negative pressure region are suspended. Maintaining a position at a distance from the means;
Relatively rotating the plate-like member and the detection means in a plane;
Detecting the outer edge of the plate-like member with the detection means, and outputting the detection data;
And a step of calculating a predetermined reference position of the plate-like member based on the detection data and positioning the predetermined reference position at a fixed position.

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