JPH05226459A - Device for determining position of semiconductor wafer - Google Patents

Abstract

PURPOSE:To detect the outer shape of a wafer in a reference position (corresponding to a point where a positioning pin comes into contact with a wafer) in noncontact manner. CONSTITUTION:A semiconductor wafer position detecting device is equipped with a Y-direction position detecting device which detects different two points located on the O-F of the wafer 1 at scanning points 80 and 90 after the orientation flat (0-F) of a wafer 1 is nearly aligned with an X direction, an X-direction position detecting device which detects the circumferential point of the wafer 1 at a scanning point 120 separate from the O-F by a prescribed distance, and a correction means which makes the rotational corrections of the wafer 1 basing on the position of O-F detected by the Y-direction position detecting device and the correction of a scanning position 120 (moved to 120 deg.) of the X-direction position detecting device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer position detecting device.

[0002]

2. Description of the Related Art In a semiconductor manufacturing apparatus or a measuring apparatus, a semiconductor wafer is aligned with a position alignment apparatus (hereinafter abbreviated as OF) before manufacturing or measuring. As shown in FIG.
The conventional alignment apparatus includes a wafer holding table 2 for holding a wafer 1, a motor 3 for rotating the wafer 1 by rotating the table 2, and a rotating wafer 1
Of the photoelectric sensor 4 composed of one or more sets of a light projecting section 4a and a light receiving section 4b arranged so that the peripheral part of the wafer crosses the optical axis, and the O / F of the wafer 1 is detected by the change in the light amount of the sensor 4, A motor control device (corresponding to 15a and 15b in FIG. 2) that stops the motor 3 (the state shown in the drawing) when OF becomes substantially parallel to the direction (X direction), and the positioning pin 1.
8, 19 and 20 and a hammer 21, and after aligning the O and F of the wafer 1 in a predetermined direction, the hammer 21 operating in the direction of the arrow moves the wafer to the positioning pin 1
It is composed of a positioning device that presses against 8, 19 and 20 to perform positioning.

On the other hand, a semiconductor manufacturing apparatus and a measuring apparatus perform exposure and measurement after they are aligned by the alignment apparatus. However, since the final alignment accuracy is required to be extremely fine, the semiconductor manufacturing equipment and measuring equipment must use the positions formed by exposing the circuit patterns together when the circuit pattern is exposed on the stage of the first semiconductor manufacturing equipment. Using the alignment mark, finer alignment is performed before manufacturing and measurement. When performing alignment using this alignment mark, first, a mark search is performed to search for the mark on the wafer 1, and then the mark is aligned with a reference position (eg, alignment mark on a mask). To do.
The search range of the mark search is the manufacturing error of the wafer,
It is determined in consideration of a delivery error and the like from the alignment device to the stage of the exposure device (measuring device).

[0004]

In the conventional alignment apparatus as described above (see FIG. 6), the wafer is positioned by applying mechanical force to the wafer by the above-mentioned positioning pins and hammers, so that the wafer is not chipped. There is a drawback that the wafer is contaminated by the generation of fine particles such as photoresist (photosensitive material) attached to the side surface of the wafer or the positioning pins.

Furthermore, due to manufacturing errors and the like, there is a deviation in the arrangement position of the positioning pin, which serves as a reference position of the alignment device, between devices such as the manufacturing device and the measuring device. When the alignment is performed by the alignment device between the manufacturing devices having this deviation, there is a drawback that the position of the pattern on the wafer becomes different if the diameter of the wafer or the O / F length varies even within the manufacturing error. is there. Therefore, the mark search on the wafer performed during the alignment performed by the conventional manufacturing apparatus or measuring apparatus is caused by the displacement of the positioning position of the positioning pin, in addition to the manufacturing error of the wafer and the delivery error from the alignment apparatus to the stage. It is necessary to search for a mark in a wide range in consideration of the positional deviation, and the mark search time may be lengthened by expanding the search range. In addition to this, since the mark search is performed on the stage of the manufacturing apparatus (measuring apparatus) that actually performs the work, there is a drawback that throughput is reduced.

Therefore, according to the present invention, the wafer is prevented from being chipped or contaminated, and the wafer can be aligned based on the outer shape of the wafer as positioned by the positioning pins of the conventional aligning apparatus. It is an object of the present invention to provide a position detecting device for a semiconductor wafer that detects a deviation amount.

[0007]

In order to solve the above-mentioned problems, the present invention has the following constitution. A semiconductor wafer position detecting device according to a first aspect of the present invention is an orientation flat aligning means (2, for aligning an orientation flat of a semiconductor wafer (1) in a substantially X direction.
3, 4, 15a, 15b), the position of two different points on the orientation flat of the wafer aligned in the substantially X direction are
Y-direction position detecting means (5a, 5b, 5c, 6, 7, 8, 9, 10) for non-contact detection along the Y direction orthogonal to the X direction as the amount of deviation from the reference position, The position of the arcuate peripheral edge of the wafer, which is separated from the orientation flat of the wafer aligned with the substantially X direction by a predetermined distance in the Y direction, is detected in a non-contact manner along the X direction as a deviation amount from a reference position. Based on the outputs of the X-direction position detecting means (11a, 11b, 12, 13) and the Y-direction position detecting means, the orientation of the wafer in which the detection position of the X-direction position detecting means is aligned with the substantially X-direction. Based on the correction means (14, 16) for correcting the position away from the flat in the Y direction by a predetermined distance, and the positions detected by the Y direction position detecting means and the X direction position detecting means, And a shift amount calculating means (17) for determining the position and inclination of the wafer.

According to a second aspect of the semiconductor wafer position detecting apparatus of the present invention, the semiconductor wafer (1) having an orientation flat is rotated by the rotation of the wafer holding table (2), and the peripheral portion of the wafer is not rotated. Orientation / flat alignment means for aligning the orientation flat of the wafer in the substantially X direction by scanning with the contact sensor (4) and stopping the rotation of the table based on the orientation / flat detection signal of the non-contact sensor ( 2,3,4,15a, 15
In the semiconductor wafer position detection device having b), the positions of two different points on the orientation flat of the wafer aligned in the substantially X direction are orthogonal to the substantially X direction as displacement amounts from the reference position. Along the direction
Non-contact Y-direction position detecting means (5a, 5b, 5)
c, 6, 7, 8, 9, 10) and the output of the Y-direction position detecting means, the angle between the orientation flat direction of the wafer and the X direction is obtained, and the wafer holding table is set. A tilt correction means (3, 4) for correcting the tilt of the orientation flat of the wafer by rotating the motor by the determined angle.
15b, 15c) and the position of the arcuate peripheral edge portion of the wafer, which is separated from the orientation flat of the wafer aligned in the substantially X direction by a predetermined distance in the Y direction, as a deviation amount from the reference position along the X direction. X-direction position detecting means (11a, 11b, 12, 1) for non-contact detection.
3) and based on the output of the Y-direction position detecting means, the detection position of the X-direction position detecting means is corrected to a position apart from the wafer orientation flat aligned with the substantially X-direction by a predetermined distance in the Y-direction. Correction means (14,
16) and a deviation amount calculation means (17) for obtaining the position and inclination of the wafer based on the positions detected by the Y-direction position detection means and the X-direction position detection means.

[0009]

According to the position detecting apparatus for a semiconductor wafer of the present invention, first, the orientation of the orientation flat of the semiconductor wafer is aligned with the substantially X direction, and then the orientation flat of the wafer is detected by the Y direction position detecting means. The positions of two different points are detected, and the inclination of the orientation flat of the wafer and the position in the Y direction are obtained. Further, when the obtained inclination of the orientation flat of the wafer is large, the inclination is corrected, and then the wafer is separated by a predetermined distance in the Y direction from the orientation flat of the wafer in which the scanning position of the X direction position detecting means is aligned with the substantially X direction. The position of the wafer is detected by correcting the position of the arcuate peripheral edge of the wafer along the X direction by the X-direction position detecting means.

Thus, the position of the wafer is detected and the amount of deviation of the wafer from the reference position is obtained.

[0011]

Embodiments of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, the position detecting device of the embodiment is
An F alignment device, a Y direction position detection device, an X direction position detection device, tilt correction control devices 15a and 15b, a Y position correction control device 16, and a deviation amount calculation device 17. Each of the O / F aligning devices includes a wafer holding table 2 that holds the wafer 1 rotatably around or at the center of the wafer 1, a motor 3 connected to the table 2 via a rotating shaft, and a table 2 on the table 2. A photoelectric sensor 4 including a light emitting portion 4a and a light receiving portion 4b arranged near the peripheral portion of the held wafer 1, and a photoelectric sensor 4 and a motor 3, which are connected to each other. The Y-direction position detecting device includes a light source 5a that emits a minute spot light in the Y direction parallel to the surface of the wafer 1. And the spot light from the light source 5a is straight light (Y direction light) and right angle light (X direction light)
A half mirror 6 that splits the light into two, a mirror 7 that reflects the right-angled light in the same direction as the straight-ahead light, mirrors 8 and 9 that reflect the two spot lights in the vertical direction with respect to the wafer 1, and a mirror 8 , 9 supporting Y mirrors so that they can be scanned in the traveling direction of the spot light, and mirrors 8, 9
The light receiving members 5b and 5c that detect the light that has passed through the wafer 1 without being blocked by the wafer 1. The X-direction position detecting device is parallel to the surface of the wafer 1 and is emitted from the light source 5a. A light source 11a that emits a minute spot light in a direction (X direction) orthogonal to the straight-ahead light;
It includes a mirror 12 that reflects the spot light from the light source 11a in the vertical direction with respect to the wafer 1, and an X mirror driving device 13 that supports the mirror 12 so that it can scan in the X direction. Further, the tilt correction control devices 15a and 15b use the wafer 1 with respect to the reference direction based on the output of the Y-direction position detection device.
The Y position correction control device 16
Controls the light source driving device 14 based on the outputs of the Y-direction position detecting device and the tilt correction control device, and the shift amount calculating device 17 controls the Y-direction position detecting device, the X-direction position detecting device and the Y-direction position detecting device. The amount of displacement of the wafer with respect to the reference position is obtained based on the output of the position correction control device.

Next, the operation of the position detecting device of the embodiment will be described. The first O / F adjustment is
When the semiconductor wafer 1 is held on the wafer holding table 2, the motor 3 rotates the wafer 1 via the table 2. Next, the photoelectric sensor 4 detects the peripheral portion of the rotating wafer 1 and outputs an OF detection signal in which the amount of received light changes at the OF portion of the wafer 1 as shown in FIG. The O / F matching control unit 15a of the motor control device 15 stops the motor 3 at the point where the peak value of the O / F signal is indicated, based on the O / F detection signal. As a result, when the O / F of the wafer 1 reaches the position of the photoelectric sensor 4 as shown in FIG. 1, the rotation of the wafer 1 is stopped, and the O / F of the wafer 1 is positioned in the substantially X direction.

After the O / F alignment is completed, the position of the wafer 1 is detected by the Y-direction position detecting device and the X-direction position detecting device. Wafer 1 OF in the Y direction position detector
When detecting the positions of the above two different points, first, the Y mirror drive device 10 is driven to move the mirrors 8 and 9 in the Y direction. As a result, as shown in FIG. 4, the light emitted from the light source 5a, which has become the spot light in the direction perpendicular to the surface of the wafer 1, scans along the Y direction as at the scanning positions 80 and 90. When the spot light from the light source 5a is blocked by the OF of the wafer 1, the respective positions of the mirrors 8 and 9 are read by the encoder 10a of the Y mirror driving device 10, and the O of the wafer 1 is adjusted. The positions Y8 and Y9 of two different points are detected.

Next, when the X-direction position detecting device detects the position of the arc-shaped peripheral edge of the wafer 1 which is separated from the OF of the wafer 1 aligned in the substantially X direction by a predetermined distance Y0, the Y-direction position detection is performed. Similarly to the device, the X mirror driving device 1
3 is driven to move the mirror 12 in the X direction. As a result, the spot light emitted from the light source 11a moves so as to scan along the X direction like the scanning position 120, so that when the spot light is blocked by the arcuate peripheral edge of the wafer 1, The position is read by the encoder 13a of the X mirror driving device 13, and the position X12 of the arcuate peripheral edge of the wafer 1 is detected.

However, when the wafer is tilted or displaced in the Y direction as shown by the dotted line 1'in FIG.
When the X-direction position is detected by the scanning position 120 of the direction position detection device, an error δ is included, and the accurate X-direction position X12
Cannot be detected, it is necessary to correct the scanning position 120 of the X-direction position detecting device when the arc-shaped peripheral edge of the wafer 1 is detected by the X-direction position detecting device. Therefore, when the position is detected by the X-direction position detection device, the detection position of the X-direction position detection device described below is corrected based on the positions of O and F detected by the Y-direction position detection device in advance.

Next, correction of the detected position of the X-direction position detecting device performed by the tilt correction control device 15c and the Y position correction control device 16 will be described with reference to FIG. It is assumed that the scanning positions 80 and 90 are adjusted to positions separated from each other by an equal interval from the Y-direction symmetry axis including the rotation center YC of the wafer holding table 2. In the tilt correction control device 15c, first, from the positions of two points on the O / F of the wafer 1 detected by the Y-direction position detecting device, the tilts of the O / F of the wafer 1 with respect to the reference X direction are expressed by Equation 1. Ask. However, the Y and Y positions of the wafer 1 detected on the mirror 8 side and the 9 side of the Y-direction position detecting device are Y8 and Y, respectively.
9, and the interval in the X direction between Y8 and Y9 is Yx.

[0017]

## EQU1 ## Δθ = tan ⁻¹ {(Y8−Y9) / Yx} Next, according to the obtained inclination Δθ, the motor driver 15
Although the inclination of the wafer 1 is corrected by rotating the motor 3 via a, it is not necessary to correct Δθ.
No correction is necessary in the case of 0, or the inclination Δθ≈0 which is negligible because it is less than or equal to the rotational resolution of the motor 3. Next, the Y position correction control device 16 causes the OF The Y position shift amount of is calculated using Equation 2.

[0018]

## EQU00002 ## ΔY = (Y8 + Y9) / 2 The value ΔY obtained here is the amount of Y position deviation from the reference position at the center of two different points on the detected O and F,
Since the inclination Δθ = 0 or Δθ≈0 is set in the inclination correction control device 15c, this ΔY can be regarded as the Y position of OF.

On the other hand, when it is necessary to largely correct the value of Δθ obtained by the equation 1, the inclination correction control device 15c
The motor driver 15b controls the motor 3 so that the wafer 1 rotates by Δθ, and the wafer 1 is rotated and corrected. After correction, the amount of deviation from the reference position of the Y and Y positions of the wafer 1 is obtained. However, when the rotation center YC of the wafer holding table 2 and the center WC of the wafer 1 are deviated, even if the inclination Δθ of 0 · F is corrected by the inclination correction control device, the X-direction position detection is performed. The Y position of the wafer OF deviates from the position detected by the device (see FIG. 5). Therefore, it is necessary to obtain the position ΔY ′ after the rotation, not the ΔY obtained by the equation 2. However, YC = Y coordinate of the rotation center, ΔY = the value obtained by the equation 2, and Δθ are the values obtained by the equation 1.

[0020]

## EQU00003 ## .DELTA.Y '= YC- (YC-.DELTA.Y) .COS.DELTA..theta. Next, the Y position correction control device determines the driving device 14 based on .DELTA.Y or .DELTA.Y' thus obtained by the formula 2 or the formula 3. The light emitting position of the light source 11a is moved by ΔY or ΔY '. As a result, the scanning position 120 of the X-direction position detector is separated from the OF of the wafer 1 aligned in the X direction by a predetermined distance.
The position is corrected to 0 ', and the X-direction position X12 can be detected at an accurate position.

Next, the deviation amount computing device corrects the two points Y8 and Y9 on the wafers O and F thus detected, the point X12 on the arc, and the θ correction from the Y position correction control device 16. Based on the signal indicating whether or not
The positional deviation θ, Y, X of the wafer 1 is obtained by using the equation 3.
The amount of positional deviation to be obtained is θ when the above-mentioned inclination Δθ is corrected.
= 0, Y = ΔY ′ obtained using Equation 3, detected X = X
In the case of not correcting the inclination Δθ, θ = Δθ obtained by using the equation 1 and Y = ΔY obtained by using the equation 2
Detected X = X12.

The manufacturing device and the measuring device correct the search range from the reference search range YA to Y1 'based on the data θ, Y, X obtained as described above, and search the alignment mark, Align with the reference position. However,
When Δθ is not corrected, it is corrected to Y1. In the above-described embodiment, the OF alignment device may be configured so that the OF of the wafer 1 is positioned substantially parallel to the predetermined direction, and the arrangement and type of the photoelectric sensor 4 and the predetermined direction. How to decide is not limited to the embodiment. Further, in the X and Y position detecting device, in order to detect the position with high accuracy, the spot light (laser light) from the light source is scanned and the scanning movement amount is read by the encoder. A condensing optical system for condensing the parallel light flux from the light source may be provided so as to become a spot light at a position intersecting with the surface, and each light receiving member 5b, 5c, 11a.
Alternatively, the line sensor may be used instead of the encoder to detect the position, and the equivalent configuration may be replaced. The reference position for position detection is the scanning position 80, 90,
The center position of 120 is set as the reference position, and the positions Y8, Y9, and X12 from the reference position are detected to obtain the deviation amounts θ, Y, and X. For example, the rotation center YC of the wafer holding table is used as the reference. It may be the position.

There are two methods for relatively correcting the inclination between the OF of the wafer 1 and the scanning position 120: a method of rotating the wafer and a method of rotating the scanning position 120. In the embodiment, the wafer is rotated. Method was used, but scanning position 12
It is also possible to rotate 0. In this case the slope Δθ
When the scanning is performed according to the obtained tilt, the light source driving device 14 is used to move the light from the light source 11 a in the Y direction, and at the same time, the X mirror driving device 13 is used to move the mirror 1.
By moving 2 along the X direction, scanning position 1
This can be realized by utilizing that the 20 is set obliquely.

Although the position detecting apparatus of the embodiment has the inclination correction correcting apparatus 15c for correcting the inclination Δθ, it does not always have to correct it by the OF adjustment so that the wafer OF
When it can be adjusted in the X direction, or when it is considered that there is no inclination (Δθ = 0), the inclination correction control device 15c for correcting Δθ is not necessary. However, to be exact, Δθ ≠
When it is regarded as 0 but Δθ = 0, the error due to the inclination of Δθ of the scanning position 120 of the X-direction position detection device is not included even if Δθ is not accurately corrected. is necessary. That is, since the above-mentioned error occurs when the rotation center YC and the wafer center WC are different from each other, regardless of the manufacturing error of the wafer (in the case of the SEMI standard; the diameter is ± 1 mm), the center of the wafer is different from the rotation center YC. The condition is that the WCs are the same (state of FIG. 4) or are located very close to each other, and the rotating wafer is hardly eccentric. In a normal wafer transfer apparatus, the center is adjusted to some extent. For example, a means for detecting the center in a non-contact manner may be provided so that the center is adjusted when the wafer is placed on the wafer holding table.

The calculation using Equation 3 is performed by scanning positions 80 and 90.
Are provided at positions separated from each other by an equal distance from the symmetry axis in the Y direction including the rotation center YC, the center ΔY of Y8 and Y9 and the rotation center YC are coaxial (the symmetry axis in FIG. 4). If it is not above and has a distance XC in the X direction (there is no ΔY on the axis of symmetry), the following Equation 4 is used instead of Equation 3.
Calculate using.

[0026]

## EQU4 ## ΔY '= YC-√ {XC ² + (YC-ΔY)
² } The deviation amount calculation device 17 is configured to newly obtain by using the formula 1, the formula 2, and the formula 3, but Δθ, ΔY, and ΔY ′ are once calculated by the inclination correction control device 15c and the Y position correction control device 16. Since they are obtained, the obtained values Δθ, ΔY, ΔY ′ may be used. However, in the case of a position detection device that does not have a tilt correction control device, the deviation Δ
It is necessary to have a configuration for obtaining θ. Further, the deviation amount θ
Was regarded as θ = 0 when the inclination Δθ was corrected, but the O of the wafer 1 after the inclination correction was again corrected by the Y-direction position detecting device.
The configuration may be such that Δθ is obtained by detecting the positions Y8 and Y9 of F, or ΔY may be obtained from the newly detected Y8 and Y9.

Further, the scanning position 1 in the alignment device
The setting of 20 may be adjusted in advance and fixed so as to be constant between the alignment devices of the devices that form the same manufacturing line, or the position data of the positioning pins and the scanning position may be stored, On the basis of the data, a scanning position adjusting device for setting a position shifted by an offset of the scanning position by using the driving device 14 as a reference position is provided so that any line device can be supported. May be. In the latter case, as shown in FIG. 4, when the scanning positions 80, 90, 120 are set according to the positioning pin arrangement positions 18, 19, 20 used in other steps,
It can be compatible with a positioning device that uses a positioning pin for positioning, which increases the degree of freedom when assembling a manufacturing line. Therefore, it is convenient for an apparatus such as an inspection apparatus that should be compatible with any alignment apparatus.
This is because the position detecting device of the present invention is a device that is provided as an accessory to a semiconductor manufacturing device or a measuring device, and since a plurality of devices are combined in the entire manufacturing process in the semiconductor manufacturing device, different positioning devices are required. It is conceivable to assemble the existing manufacturing devices. However, as described in the subject, it takes time to search for the alignment mark on the wafer in the next alignment, which may reduce the throughput. It is difficult to assemble. Furthermore, in the case of a device that inspects wafers manufactured on an unspecified number of manufacturing lines, such as a measuring device, it is easy to think that it will take time without looking for the marks on the wafer if there is an alignment error between the manufacturing lines. Be done.

Other devices have been proposed which detect the edge of the wafer without contact and perform alignment, but these devices find the center of the wafer from three points on the arc-shaped peripheral edge of the wafer, and further It is an apparatus for aligning the center of the wafer with the center of rotation of the wafer holding table. Since this alignment device can detect dust without contact as in the present invention, the alignment device separates the wafer holding table, X, Y and Δθ from the stage of the manufacturing apparatus main body.
Since it requires a stage that moves to a position, it has a drawback that it is a very large-scale device, and in the case of a positioning device using a positioning pin, the position of the wafer is adjusted from the position of the positioning pin to perform positioning based on the positioning pin. The distance to the center varies, and it is difficult to maintain compatibility. When it is necessary to maintain compatibility with such a positioning device, the position detecting device of the embodiment is provided with a detecting means for detecting the positions of three different arc-shaped peripheral portions in a non-contact manner, and the wafer as a wafer center. It is possible to provide by means for controlling so as to switch and detect in the calculation process depending on whether the alignment is performed by the required alignment device or the alignment device by the positioning pin. With such a configuration, lines can be assembled regardless of the type of the alignment device, so that the amount of misalignment of the wafers aligned by different alignment devices and having alignment marks can be accurately obtained. However, the obtained wafer position deviation is not the position detection device but the manufacturing device (measuring device).
After passing to the stage, it will be corrected by the offset of the running of the stage, so another stage is not required.

[0029]

In the position detecting device of the present invention, the amount of positional deviation of the semiconductor wafer with respect to the reference position is detected in a non-contact manner, so that contamination of the semiconductor wafer due to dust generation can be eliminated. Further, the position detecting device of the present invention only detects the position, but if the accurate position of the wafer can be detected, the mark is not detected at the time of alignment using the alignment mark on the wafer in the next manufacturing device. By correcting the position to be searched for electrically, optically, or by running the stage, it is possible to perform alignment equivalent to the case where alignment is performed with the positioning pin.

[Brief description of drawings]

FIG. 1 is a perspective view showing a schematic configuration of a position detection device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a control configuration of the position detection device according to the embodiment of the present invention.

FIG. 3 is a diagram showing an output signal of a photoelectric sensor 4.

FIG. 4 is an explanatory diagram of scanning positions of the position detecting device according to the embodiment.

FIG. 5 is an explanatory diagram used for explaining a correction method of the position detection device according to the embodiment.

FIG. 6 is a perspective view showing a conventional alignment device.

[Explanation of symbols]

 1, 1 '... Semiconductor wafer 2 ... Wafer holding table 3 ... Motor 4 ... Photoelectric sensor 15a ... OF alignment control unit 15b ... Motor driver 5a, 11a ... Light source 5b, 5c, 11b ... Light receiving member 6 ... Half mirror 7 ... Reflecting mirrors 8, 9, 12 ... Scanning mirrors 10, 13 ... Mirror driving device 14 ... Light source driving device 16 ... Y position correction control device 15c ... Tilt correction control unit 17 ... Deviation amount calculation device

Claims (2)

[Claims] 1. A semiconductor wafer position detection device having orientation flat alignment means for aligning a semiconductor wafer orientation flat in substantially the X direction, comprising: a wafer orientation alignment in the substantially X direction;
Aligning the positions of two different points on the flat with the substantially X direction in a non-contact manner along a Y direction orthogonal to the substantially X direction as a deviation amount from a reference position. Wafer orientation
An X-direction position for non-contact detection along the X-direction, which is the position of the arcuate peripheral edge of the wafer that is separated from the flat along the Y-direction toward the center of the wafer by a predetermined distance, as the amount of deviation from the reference position. Based on the outputs of the detection means and the Y-direction position detection means, a predetermined position is set in the center direction of the wafer from the orientation flat of the wafer in which the detection position of the X-direction position detection means is aligned with the substantially X-direction. Correction means for correcting to a position separated by a distance, and deviation amount calculation means for obtaining a positional deviation of the semiconductor wafer with respect to the reference position based on the positions detected by the Y-direction detecting means and the X-direction detecting means. Characteristic semiconductor wafer position detector. 2. A semiconductor wafer having an orientation flat is rotated by rotation of a wafer holding table, a peripheral portion of the wafer is scanned by a non-contact sensor, and the table is detected based on an orientation flat detection signal of the non-contact sensor. By stopping the rotation of the
In a position detecting device for a semiconductor wafer having orientation flat alignment means for aligning with a direction, the orientation of the wafer aligned with the substantially X direction
A Y position detecting unit that detects the positions of two different points on the flat in a non-contact manner as a deviation amount from a reference position along a Y direction orthogonal to the substantially X direction, and a Y direction position detecting unit. An inclination that corrects the inclination of the orientation flat of the wafer by finding the angle between the orientation flat direction of the wafer and the X direction based on the output and rotating the wafer holding table by the obtained angle. The correction means and the position of the arcuate peripheral edge of the wafer, which is separated from the orientation flat of the wafer along the Y direction toward the center side of the wafer by a predetermined distance, as the amount of deviation from the reference position along the X direction. X-direction position detection means for non-contact detection, and detection of the X-direction position detection means based on the output of the Y-direction position detection means Based on the positions detected by the Y-direction detecting means and the X-direction detecting means, the correction means for correcting the position of the wafer from the orientation flat of the wafer along the Y direction toward the center of the wafer by a predetermined distance. A semiconductor wafer position detection device, comprising: a displacement amount calculating means for determining a displacement of the semiconductor wafer with respect to a reference position.