JP2007248473A - Bonding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for measuring accurately a position of a tool in offset correction. <P>SOLUTION: A laser diode of a light source is arranged in a position of irradiating the tool 4 orthogonally downwards with reference patterns L<SB>x</SB>, L<SB>y</SB>respectively from an X-direction and a Y-direction, when providing a prism 130 provided with a reference mark 130a on an upper face, on a reference block 11, and when arranging a position detecting camera 7 in a just upper side of the reference mark 130a. The reference mark 130a is imaged by the position detecting camera 7 to find shift amounts ΔX<SB>1</SB>, ΔY<SB>1</SB>. Then, the tool 4 is imaged under this condition by the position detecting camera 7 via the prism 130 to find shift amounts ΔX<SB>2</SB>, ΔY<SB>2</SB>. An accurate offset amount is calculated based on the shift amounts, and a deviation amount between the reference mark 130a and an imaging reference position of the laser diode. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an offset measurement method, a tool position detection method, and a bonding apparatus, and more particularly, to a method and apparatus capable of accurately calculating an offset amount between a position detection imager that images a bonding component and a processing member such as a tool.

  Hereinafter, a wire bonding apparatus will be described as an example. A bonding head mounted on an XY table includes a position detection camera for imaging a reference pattern on a bonding component and a bonding tool for specifying a bonding point on the bonding component such as a semiconductor device. And a bonding arm attached to the. When the position detection camera images the reference pattern on the bonding part, the optical axis of the position detection camera and the axis of the tool are arranged so that the tool and the bonding arm do not interfere with the visual field of the position detection camera. Are assembled to the bonding head with a certain distance. In general, the distance between the optical axis of the position detection camera and the axis of the tool is called an offset.

  Since the position detection camera obtains a reference point for knowing the position where the tool is moved, it is very important to know how much the position detection camera is offset from the tool. However, the actual offset amount changes with the thermal expansion of the camera holder and bonding arm due to radiant heat from the high-temperature bonding stage, so the offset amount is calibrated at the beginning of the bonding operation and at appropriate timing between operations. There is a need to.

  For this purpose, conventionally, an indentation is made with a tool at an appropriate location within the bonding range, and the position of the indentation is detected by a position detection camera, whereby the position of the tool is detected, and the offset amount is calibrated based on the detected position. A method has been proposed (for example, JP 59-69939 A). In this method, predetermined image processing is performed on the photoelectrically converted image data from the position detection camera to obtain the coordinates of the center of the indentation, and the offset amount is calculated based on this.

  However, this conventional configuration has a problem that the impression of the tool is not always clear and the shape of each impression is different from that of a dedicated pattern suitable for image processing, so that detection is not always accurate.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a novel means capable of accurately detecting the position of a tool.

  A bonding apparatus according to the present invention integrates a position detection image pickup device that picks up an image of a bonding component, a tool that is provided offset from the position detection image pickup device and processes the bonding component, and a position detection image pickup device and the tool. An optical path converting means for guiding the image light of the tool to a position detection image pickup device arranged directly above, and a reference mark provided on the upper surface of the optical path converting means. A reference mark arranged at a reference position associated with a reference position in the plane of the XY table, and a tool having an axis perpendicular to the XY plane arranged at a position associated with the reference position in the plane of the XY table The X-direction reference pattern and the Y-direction reference pattern with a predetermined inclination angle with respect to the plane of the XY table The amount of deviation in the X direction between the imaging reference position provided at a predetermined position in the longitudinal direction of the tool and the reference position is set to be the same as the amount of offset in the X direction, and the deviation in the Y direction. A light source whose amount is set to zero, and a calculation control device for obtaining an offset amount in the XY plane. The calculation control device picks up the reference mark with the position detection image pickup device and picks up the reference mark and the position detection image pickup. Based on the measured value of the positional relationship between the tool and the optical path conversion means, the tool is imaged by the position detection image sensor, and the reference is based on the contour of the imaged tool and the reference pattern on the tool. Measurement value obtained by measuring the positional relationship between the mark and the tool, and imaging when the reference pattern on the tool is imaged by the position detection image sensor via the optical path changing means And amount of deviation between the reference position and the reference position, and obtains the offset amount in the XY plane based on.

  When a reference pattern is projected toward a tool from a light source arranged at a predetermined position associated with a reference position in the reference plane with a predetermined inclination angle with respect to the reference plane, the reference pattern projected on the tool is the position of the tool. Accordingly, the position and shape of the tool are detected in accordance with the position of the tool, whereby the position of the tool can be accurately detected.

  In addition, the light source can project the X-direction reference pattern and the Y-direction reference pattern from the upper side to the lower side, with the direction toward the upper surface of the optical path changing unit as the upper side, and from the lower side to the upper side. Thus, the X-direction reference pattern and the Y-direction reference pattern can be projected.

  In addition, since the reference member or the reference mark is installed at a predetermined position associated with the reference position in the reference plane, the measurement of the position of the tool and the position of the image sensor for position detection are performed via the reference member or the reference mark. Can be performed very accurately.

  In addition, a bonding apparatus according to the present invention includes a position detection image pickup device that picks up an image of a bonding component, a tool that is provided offset from the position detection image pickup device, and processes the bonding component, a position detection image pickup device, and a tool. In a bonding apparatus having an XY table that integrally moves the optical path conversion means for guiding the image light of the tool to the position detection image pickup device arranged directly above, and a reference position in the plane of the XY table. The reference member arranged at the reference position and the reference member in the plane of the XY table are arranged at a position associated with the reference position, and a predetermined axis with respect to the plane of the XY table is directed to a tool having an axis perpendicular to the XY plane. The reference member is directed toward the reference member standing upright with respect to the XY plane with the inclination angle of A light source for projecting each reference pattern and an arithmetic control device for obtaining an offset amount in the XY plane are provided, and the arithmetic control device images the reference member and the tool by the position detection image sensor via the optical path changing means. The positional relationship between the reference member and the tool was measured based on the reference member contour, the reference member side reference pattern on the reference member, the tool contour, and the tool side reference pattern on the tool. Obtaining an offset amount in the XY plane based on the measurement value and the measurement value obtained by imaging the reference member with the position detection image pickup device and measuring the positional relationship between the reference member and the position detection image pickup device. Features.

  Since the reference pattern is projected from the light source to both the tool and the reference member, and the position of the tool is measured based on the image light of both the tool and the reference member, the positional relationship between the tool and the light source, The positional relationship between the reference member and the tool can be accurately obtained based on both the positional relationship between the light source and the light source.

  Furthermore, regarding the measurement of the position of the tool, the measurement value obtained by measuring the position of the tool based on the reference pattern projected onto the tool, the image light of the tool and the reference member are guided to the position detection image pickup device, the tool and the reference member, The position of the tool can be obtained more accurately by using the measured value obtained by measuring the positional relationship with the image sensor for position detection.

  Furthermore, a bonding apparatus according to the present invention includes a position detection image pickup device that picks up an image of a bonding component, a tool that is provided offset from the position detection image pickup device, and processes the bonding component, a position detection image pickup device, and a tool. In a bonding apparatus having an XY table that integrally moves the optical path conversion means for guiding the image light of the tool to the position detection image pickup device arranged directly above, and a reference mark provided on the upper surface of the optical path conversion means A reference mark arranged at a reference position associated with a reference position in the plane of the XY table, and a tool axis perpendicular to the XY plane arranged at a position associated with the reference position in the plane of the XY table A light source that emits ring-shaped light having a predetermined inclination angle with respect to the plane of the XY table. A light source that projects a reference pattern to the entire circumference of the tool at an imaging reference position provided at a predetermined position in the longitudinal direction of the tool, and an arithmetic control device that calculates an offset amount in the XY plane. The reference mark is imaged by the position detection image sensor, the measured value of the positional relationship between the reference mark and the position detection image sensor is measured, and the tool is imaged by the position detection image sensor via the optical path changing means. An offset amount in the XY plane is obtained based on a measured value obtained by measuring a positional relationship between the reference mark and the tool based on the contour of the imaged tool and a reference pattern on the tool. And

  Also in this case, it is preferable that the light source projects the reference pattern from the lower side to the upper side with the direction of the upper surface of the optical path changing unit as the upper side.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 to FIG. 9 are reference embodiments serving as the basis of each embodiment of the present invention, but will be referred to as the first embodiment for convenience here. Embodiments of the present invention are second to fifth embodiments described later. The contents in the first embodiment can be applied to each embodiment of the present invention as far as possible. FIG. 1 shows a wire bonding apparatus common to the first to fifth embodiments. As shown in the figure, a bonding arm 3 is provided on the bonding head 2 mounted on the XY table 1, and the bonding arm 3 is driven in the vertical direction (that is, the Z direction) by a vertical driving means (not shown). A tool 4 is attached to the tip of the bonding arm 3, and a wire 5 is inserted through the tool 4. Further, a camera holder 6 is fixed to the bonding head 2, and a position detection camera 7, which is a photoelectric conversion type image pickup device provided with a charge coupled device (CCD), is fixed to the tip of the camera holder 6. Yes. The optical axis 7a of the position detection camera 7 and the axis 4a of the tool 4 are both vertically oriented in the vertical direction, that is, in the Z direction. The optical axis 7a and the axis 4a are offset by offset amounts Xt and Yt in the XY direction. The XY table 1 is configured so that it can be accurately moved in the X direction and the Y direction by two pulse motors (not shown) installed in the vicinity thereof, so that the position detection camera 7 and the tool 4 are offset. While maintaining the amounts Xt and Yt, they move integrally in the X and Y directions. These are well-known structures.

  A rail 13 is provided in the vicinity of a bonding stage 10 for positioning and mounting a semiconductor device (not shown), and a reference table 11 on which a reference member 30 is erected is fixed on the upper surface of the rail 13. On the reference table 11, a prism 18, a laser diode 15 as a light source for a reference pattern, and a laser diode 16 as a transmitted light source are installed.

  As shown in FIG. 2, the laser diode 15 is fixed to the upper end of the light source table 14 provided on the reference table 11 with an inclination angle of 45 degrees downward with respect to the horizontal direction. Project toward the tip.

  As the reference pattern L, a horizontal straight line pattern as shown in FIG. Therefore, when the tool 4 is at the position A in FIG. 3A, the reference pattern L is projected in the middle of the tool 4 as shown in FIG. 3C, and the tool 4 is at the position B. In some cases, the reference pattern L is projected near the lower end of the tool 4 as shown in FIG. Thus, due to the projection of the reference pattern L with an inclination angle with respect to the horizontal direction, the reference pattern L is projected at different height positions according to the position of the tool 4 in the X direction.

  The laser diode 16 is set to emit parallel light toward the reference member 30. The reflecting surface 18a of the prism 18 intersects at an angle of 45 ° with respect to the horizontal direction. Therefore, in a posture in which the tool 4 is brought close to the reference member 30, the optical image of the lower end of the tool 4 and the upper end of the reference member 30 is detected as a shadow with respect to the light of the laser diode 16 via the reflecting surface 18 a of the prism 18. Guided to the camera 7. Instead of the prism 18, a mirror body such as a mirror may be used. A half mirror may be used. That is, any optical path changing means that can guide the image light of the tool 4 to the position detection camera 7 may be used, and a prism, mirror, half mirror, or the like can be used as an optical element made of glass, resin, or the like.

  The distance d2 between the center 18b of the reflecting surface of the prism 18 and the axis 30a of the reference member 30 is substantially equal to the offset amount Xt in the X direction between the optical axis 7a of the position detection camera 7 and the axis 4a of the tool 4. .

  The position detection camera 7 includes a lens 7b that is a telecentric lens. The telecentric lens here refers to a telecentric optical system, that is, an optical system configured such that the principal ray to be imaged passes through the rear focal point of the lens. The telecentric lens has a wide tolerance for the positional deviation in the opposite direction to the imaging surface, and particularly when irradiated with transmitted light that is parallel light, the size of the image (that is, from the optical axis) It is generally known that the (distance) does not change and is used in various industrial measuring instruments. However, in a bonding apparatus, a telecentric lens or an optical system having characteristics close to telecentric is widely used.

  As shown in FIG. 4, the XY table 1 is driven via the XY table control device 21 according to a command from the arithmetic control device 20. An image picked up by the position detection camera 7 is converted into an electrical signal and processed by the image processing device 22, and accurate offset amounts Xt and Yt are calculated by a calculation control device 20 composed of a computer by a method described later. The memory 23 stores offset amounts Xw and Yw in advance. Therefore, when the difference between the accurate offset amounts Xt and Yt and the offset amounts Xw and Yw stored in the memory 23 in advance, that is, the offset calibration amounts are ΔX and ΔY, the accurate offset amounts Xt and Yt are stored in advance. The offset amounts Xw and Yw and the offset calibration amounts ΔX and ΔY have the relationship of Equation 1. In the figure, reference numeral 24 denotes an input / output device.

(Equation 1)
Xt = Xw + ΔX
Yt = Yw + ΔY
Next, a method for calculating the offset amounts Xt and Yt will be described. First, as indicated by the solid line in FIG. 5, the XY table is set via the XY table control device 21 in accordance with a command from the arithmetic processing unit 20 (FIG. 4) so that the axis 4a of the tool 4 is positioned in the vicinity of the reference member 30. 1 is driven, and the tool 4 is lowered to the level of the reference member 30. Here, the tool 4 may be a position where the position detection camera 7 can image the tool 4 and the reference member 30, and the axis 4 a of the tool 4 does not need to coincide with the axis 30 a of the reference member 30.

Then, both the tool 4 and the reference member 30 are imaged by the position detection camera 7, and the positional relationship between them, that is, ΔX ₁ and ΔY ₁ are measured.

Here, by the irradiation of the laser diode 16, the image light of the tool 4 and the reference member 30 is reflected by the reflection surface 18 a of the prism 18 as a shadow with respect to the light of the laser diode 16 and guided to the position detection camera 7. As a result, the position detection camera 7 obtains an image as shown in FIG. Here, by performing appropriate image processing on this image, based on the position coordinates of the contours of the tool 4 and the reference member 30, the amount of deviation between them, that is, the axis 4a of the tool 4 and the axis 30a of the reference member 30 is obtained. A displacement amount ΔY _{1 in} the Y direction is calculated.

On the other hand, as described above, the reference pattern L projected from the laser diode 15 has different heights along the axial direction of the tool 4 depending on the position of the tool 4 in the X direction from the reference position in the plane of the XY table. It is projected to the position. Here, based on the contour of the tool 4, the contour of the reference pattern L, and the inclination angle of the reference pattern L with respect to the plane of the XY table, the position of the tool 4 in the X direction from the reference position in the plane of the XY table, and the reference The relationship with the height position along the axial center direction of the projection tool 4 on the tool 4 of the pattern L can be obtained. Therefore, by applying appropriate image processing to the image showing the height of the reference pattern L along the axial direction of the tool 4 in FIG. 6, the position of the tool 4 in the X direction from the reference position in the plane of the XY table. Is required. Here, the position of the axial center 30a of the reference member 30 by the reference position in the plane of the XY table, the deviation amount [Delta] X ₁ in the X direction with the axis 30a of the axis 4a and the reference member 30 of the tool 4 Calculated.

When the positional relationship between the tool 4 and the reference member 30, that is, ΔX ₁ and ΔY ₁ is measured in this way, the arithmetic and control unit 20 next uses the offset amounts Xw and Yw stored in advance in the memory 23 to determine the XY table. The XY table 1 is driven via the control device 21 to move the position detection camera 7 to the vicinity of the reference member 30 as indicated by a dotted line in FIG. In this state, the reference member 30 is imaged (FIG. 7), and the image is subjected to appropriate image processing, whereby the amount of deviation between the axis 30a of the reference member 30 and the optical axis 7a of the position detection camera 7 is obtained. ΔX ₂ and ΔY ₂ are calculated.

If the offset amounts Xw and Yw stored in advance are accurate offset amounts Xt and Yt, the offset calibration amounts ΔX and ΔY are 0, so ΔX ₁ and ΔY ₁ coincide with ΔX ₂ and ΔY _2. It is. However, if the offset amounts Xw and Yw stored in advance are approximate values, or if the camera holder 6 or the bonding arm 3 expands due to thermal influence and the offset amounts Xt and Yt change, ΔX ₁ , ΔY ₁ do not coincide with ΔX ₂ , ΔY ₂ , and errors (offset calibration amounts) ΔX, ΔY occur. Therefore, the offset calibration amounts ΔX and ΔY are calculated by Equation _{2 from} the measured values ΔX ₁ and ΔY ₁ and the measured values ΔX ₂ and ΔY ₂ .

(Equation 2)
ΔX = ΔX ₁ −ΔX ₂
ΔY = ΔY ₁ −ΔY ₂
Therefore, the arithmetic and control unit 20 calculates the offset calibration amounts ΔX and ΔY according to Equation 2, and adds the offset calibration amounts ΔX and ΔY to the offset amounts Xw and Yw stored in advance according to Equation 1 to obtain accurate offset amounts Xt and Yt. And the offset amounts Xw and Yw stored in the memory 23 are corrected (updated) to the correct offset amounts Xt and Yt. The offset amounts Xw and Yw thus determined are used as offset amounts for the position detection camera 7 and the tool 4 in subsequent bonding operations.

  As described above, in the first embodiment, the reference pattern L is projected toward the tool 4 with an inclination angle with respect to the horizontal direction from the laser diode 15 arranged at a predetermined position, and the reference pattern L projected on the tool 4 is projected. Based on this, the position of the tool 4 in the X direction is measured. For this reason, the reference pattern L is projected at different height positions according to the position of the tool 4, and based on this, the position of the tool 4 in the X direction can be accurately detected.

  Further, since the position of the position detection camera 7 is measured by imaging the reference member 30 with the position detection camera 7, the position detection camera 7 that is originally for imaging a semiconductor device. Can be used to measure the offset amount.

  Further, the position of the position detection camera 7 is measured using the reference member 30 as a reference, the position of the tool 4 in the Y direction is measured using the reference member 30 as a reference, and these measurement values and position detection between both measurements are performed. Since the offset amount is obtained based on the offset amounts Xw and Yw stored in advance, which are the movement amounts of the camera 7 and the tool 4, the offset amount can be measured very accurately through the reference member 30. .

  Further, since the prism 18 for guiding the image light of the tool 4 and the reference member 30 to the position detection camera 7 is provided, the position detection camera 7 can be used not only for detecting the position of the position detection camera 7 itself but also for the tool 4. It can also be used to detect the position of

  Further, regarding the measurement of the position of the tool 4, the position detection camera uses the measurement value in the X direction obtained by measuring the position of the tool 4 based on the reference pattern L projected on the tool 4 and the image light of the tool 4 and the reference member 30. 7 and the Y-direction measurement value obtained by measuring the positional relationship between the tool 4 and the reference member 30 with the position detection camera 7 is generally used. A method based on the outline image of the tool 4 having a wide visual field can be used, and measurement in the X direction with a relatively small deviation amount can be accurately performed based on the image of the reference pattern L.

  Note that, as in the first embodiment, the measurement of the position of the tool 4 in the X direction is performed based on the reference pattern L projected on the tool 4, while the measurement of the position of the tool 4 in the Y direction is performed on the contour of the tool 4. In addition to the configuration performed based on the image of the above, the measurement of the tool 4 may be performed by projecting the reference pattern in both the X direction and the Y direction. A light source having a predetermined inclination angle is provided in the Y direction with respect to the reference member 30, and the reference member 30 may be imaged with a dedicated camera from the Y direction. Further, the light obtained when the reference member 30 is viewed from the Y direction. An optical member that guides the image to the position detection camera 7 may be provided.

  In the first embodiment, the irradiation direction of the laser diode 15 is obliquely downward with respect to the horizontal direction, but conversely, the laser diode 15 is disposed obliquely downward with respect to the position of the tool 4 in the measurement posture. It is good also as a structure which irradiates the tool 4. FIG.

  In the first embodiment, the irradiation direction of the laser diode 15 is 45 degrees below the horizontal direction. However, the irradiation direction of the laser diode 15 may be another angle, and the higher the tilt angle, the higher the measurement accuracy. Obtainable. In the first embodiment, since the measurement of the amount of deviation of the tool 4 in the X direction is performed based on the light image of the tool 4 viewed from the horizontal direction, conversion to the X coordinate is easy in image processing. Although there is an advantage, if the irradiation direction by the laser diode 15 and the detection direction of the image are different from each other, the deviation amount of the tool 4 in the X direction can be measured by the same method. On the other hand, the measurement of the amount of deviation of the tool 4 in the X direction may be performed based on an optical image obtained by viewing the tool 4 from an angle different from the horizontal direction.

  In the first embodiment, the laser diode 15 is fixed to the reference table 11 via the light source table 14. However, the laser diode 15 can be installed at any other position. It is good also as a structure fixed to the camera 7 for cameras.

  Further, in the first embodiment, the transmitted light illumination is performed by the laser diode 16, but reflected light may be used for the measurement of the position based on the contour image of the tool 4, for example, the position detection camera 7. Alternatively, the light source may be built in and the tool 4 may be illuminated through the prism 18. In the first embodiment, the laser diode 16 set so as to generate parallel light is used. However, instead of such a configuration, a pinhole and a lens are combined with an arbitrary light source and thereby parallel. It is good also as a structure which obtains light. As the light source in this case, for example, an LED (light emitting diode), a halogen lamp, a tungsten lamp, or an optical fiber exit is suitable. There is no need for a pinhole, but if no pinhole is used, the parallelism of the light beam is inferior.

  In the first embodiment, the reference pattern L is a horizontal straight line pattern. However, the reference pattern L may have other configurations, for example, spot light as shown in FIG. Such a zebra pattern, a lattice pattern as shown in FIG. 8C, a color pattern as shown in FIG. Further, a sine pattern as shown in FIG. 8D, that is, a pattern having a sine distribution of light intensity may be used. In this case, imaging with illumination of a pattern whose phase is different by 120 degrees is executed three times. By superimposing these images, the influence of scratches and dirt on the surface of the tool 4 can be canceled and measurement can be performed with high accuracy.

  When the position detection camera 7 is also used for imaging the tool 4 and the reference member 30 as in the first embodiment, the distance from the bonding component to the position detection camera 7 is the tool 4 and the reference member 30. It is conceivable that the size of the latter image changes due to the difference from the distance from the position detection camera 7 to the position detection camera 7, and as a result, the positional relationship between the tool 4 and the reference member 30 cannot be detected correctly. In this regard, in the first embodiment, the lens 7b, which is a telecentric lens having a characteristic that the size of the image does not change even if the subject position changes, is provided in the position detection camera 7, so that the positional relationship based on these imagings It is preferable that both detections can be accurately performed.

  Further, in the first embodiment, the tool 4 and the reference member 30 are configured to measure a deviation amount between the X direction and the Y direction, that is, using images captured at different 90 ° angles from each other. However, the relative angle between them may not be 90 °. In addition, the position where the reference member is provided is not limited to the position shown in the first embodiment, and is preferably as close as possible to the bonding component. Furthermore, any protrusion of the bonding component itself (for example, the lead frame) is provided. It may be used as a reference member.

  In the first embodiment, the positional relationship between the position detection camera 7 and the reference member 30 is determined by measuring the positional relationship between the tool 4 and the reference member 30 and then moving the tool 4 and the position detection camera 7. However, the order of both measurements may be reversed, and such a configuration is also included in the scope of the present invention.

  In the first embodiment, the optical images of the tool 4 and the reference member 30 are guided as they are to the position detection camera 7 via the prism 18, but as shown in FIG. It is good also as a structure provided with the correction | amendment lens 50 in between. The correction lens 50 is fixed to the reference table 11 by a correction lens support base 52. When only the lens 7e is used, the focus position is the center 18b of the reflecting surface 18a of the prism 18 that is separated from the imaging surface of the position detection camera 7 by a distance d1. In addition, when both the lens 7e and the correction lens 50 are used, the focus position is the axis 30a of the reference member 30 that is separated from the imaging plane of the position detection camera 7 by a distance d1 + d2. The lens 7e attached to the position detection camera 7 may not be a telecentric lens. Also in this modification, the light source base 14 and the laser diode 15 are installed as in the configuration of FIG. 2, but the illustration is omitted in FIG.

  In this variation, however, both the tool 4 and the reference member 30 are imaged by the position detection camera 7 via the correction lens 50 and the prism 18. In this case, the distance to the focus position is d1 + d2 through the correction lens 50. Next, the position detection camera 7 is moved to approach the reference member 30, and in this state, the reference member 30 is directly imaged by the position detection camera 7. In this case, the distance to the focus position is d1 because the correction lens 50 is not passed. As described above, in this modification, the distance to the focus position is changed by the reference table 11 and the correction lens 50 that is integrally held with the reference unit 30, so the tool 4 and the reference member 30 are imaged. The correction lens 50 is interposed in the optical path in accordance with the movement to the posture, and both the tool 4 and the reference member 30 are imaged by the position detection camera 7, and the reference member is captured by the position detection camera 7. There is an advantage that the focusing operation of the position detection camera 7 by mechanical / electrical means is not required between the case where 30 is directly imaged.

Next, a second embodiment will be described. In the first embodiment, between the measurement of the positional relationship between the tool 4 and the reference member 30 and the measurement of the positional relationship between the position detection camera 7 and the reference member 30, the tool 4 and the position detection camera 7 Since the offset amount is obtained by adding the movement amount, the offset amount can be measured very accurately via the reference member 30 which is a common reference point for both measurements. It is also possible to adopt a configuration in which the tool 4 and the position detection camera 7 are not moved between them (that is, the movement amount is zero). That is, as shown in FIG. 10, when the prism 130 provided with the reference mark 130a on the upper surface is provided on the reference table 11, and the position detection camera 7 is arranged right above the reference mark 130a, the tool 4 is placed in the X direction. A light source table 14 and a laser diode 15 (not shown) similar to those in FIG. 2 are respectively arranged at positions where the reference patterns L _x and L _y are irradiated obliquely downward from the direction and the Y direction, respectively. The amount of deviation d3 in the X direction between the reference mark 130a and the imaging reference position of the laser diode 15 is equal to the offset amount Xw stored in advance in the above embodiment, and the amount of deviation in the Y direction is zero. In this configuration, a correction lens similar to the correction lens 50 in FIG. 9 may be provided.

Therefore, in this configuration, the reference marks 130a are imaged by the position detection camera 7, converted into electric signals, and subjected to image processing to obtain the shift amounts ΔX ₁ and ΔY ₁ . Next, in this state, the tool 4 is imaged by the position detection camera 7 via the prism 130, and an image based on the contour image of the tool 4 in the captured image and the image of the reference pattern projected on the tool 4 is displayed. By performing the processing, deviation amounts ΔX ₂ and ΔY ₂ are obtained. Then, an accurate offset amount is calculated by the above formulas 1 and 2 from these shift amounts and the shift amount between the reference mark 130a and the imaging reference position of the laser diode 15.

  According to this configuration, it is not necessary to move the position detection camera 7 and the tool 4 between the measurement of the position of the position detection camera 7 and the measurement of the position of the tool 4, so that the offset can be corrected quickly. There are advantages to be implemented. In this configuration, although the measurement includes a deviation in the positional relationship between the reference mark 130a and the imaging reference position of the laser diode 15, the configuration is such that the positional relationship between the two is less likely to be out of order, and both By calibrating the positional relationship, it is possible to minimize the error.

Next, a third embodiment will be described. In the third embodiment, as shown in FIG. 11A, the reference patterns L _X1 and L _X2 are obliquely directed downward from a laser diode (not shown) as a common light source on both the tool 4 and the reference member 30. To project. The reference patterns L _X1 and L _X2 may be projected from separate light sources, but in that case, the distance and angle between the two light sources need to be set precisely. In this configuration, a correction lens similar to the correction lens 50 in FIG. 9 may be provided.

In this configuration, when the tool 4 and the reference member 30 are imaged by the position detection camera 7 via the prism 18, the reference pattern L _X1 projected on the tool 4 and the reference pattern projected on the reference member 30 are used. An image with L _X2 , that is, an image as shown in FIG. By performing image processing on this image, deviation amounts ΔX ₂ and ΔY ₂ between the tool 4 and the reference member 30 are obtained, and an accurate offset amount is calculated based on the deviation amounts ΔX ₂ and ΔY ₂ .

As described above, in the third embodiment, the reference patterns L _X1 and L _X2 are projected onto both the tool 4 and the reference member 30, and the position of the tool 4 is measured based on these images. The measured value of the positional relationship between the tool 4 and the light source can be corrected based on the positional relationship between the reference member 30 and the light source, and the positional relationship between the reference member 30 and the tool 4 can be obtained with higher accuracy.

  Next, a fourth embodiment will be described. In the fourth embodiment, as shown in FIG. 12, a prism 130 having a reference mark 130a similar to that shown in FIG. 10 on the upper surface is provided on the reference table 11, while the position detection camera 7 is attached to the reference mark 130a. When arranged directly above, a ring-shaped light source 115 is installed at a position on the reference table 11 that surrounds the axis 4a of the tool 4, and this ring-shaped light source 115 is located in the middle of the longitudinal direction of the tool 4 from the entire circumference. The reference pattern L3 is set to be projected obliquely upward at a certain imaging reference position. In this configuration, a correction lens similar to the correction lens 50 in FIG. 9 may be provided.

Accordingly, in this configuration, the tool 4 is imaged by the position detection camera 7 via the prism 130, and the contour image of the tool 4 in the captured image and the image of the reference pattern L ₃ projected on the tool 4 are obtained. Based on this, image processing is performed to obtain deviation amounts ΔX ₂ and ΔY _2, and an accurate offset amount is calculated based on the deviation amounts ΔX ₂ and ΔY ₂ .

  Here, the image obtained by imaging of the tool 4 differs depending on the position of the axis 4a of the tool 4, and when the center 115a of the ring-shaped light source 115 and the axis 4a of the tool 4 coincide, FIG. a), but when the axis 4a of the tool 4 is displaced in the Y direction, FIG. 13B, and when the axis 4a is displaced in the −Y direction, FIG. 13C and −X, respectively. When it is shifted in the direction, it is as shown in FIG. 13D, and when it is shifted in the X direction, it is as shown in FIG. Based on such a change in the image, the position of the tool 4 can be accurately obtained in the fourth embodiment.

Next, a fifth embodiment will be described. In the fifth embodiment shown in FIG. 14, the reference patterns L ₄ and L ₅ , which are horizontal lines similar to those shown in FIG. Is different from the second embodiment in that the projection direction is obliquely upward. The light source is not shown in FIG.

  Thus, an image obtained by imaging of the tool 4 in this configuration differs depending on the position of the axis 4a of the tool 4, and when the axis 4a of the tool 4 is at the imaging reference position, as shown in FIG. However, when the axis 4a of the tool 4 is displaced in the Y direction, FIG. 15B, and when it is displaced in the −Y direction, FIG. 15C, it is displaced in the −X direction. FIG. 15D shows the case, and FIG. 15E shows the case where it is displaced in the X direction. Based on such image changes, the position of the tool 4 can be accurately obtained in the fifth embodiment.

  In each of the above embodiments, the case where the processing member according to the present invention is a single tool 4 has been described. However, the present invention can measure the offset amount between a plurality of processing heads and position detection image sensors, It is also possible to apply the measurement of the offset amount between the processing heads.

  In the above embodiment, the prisms 18 and 130 are used as the optical member. However, the optical member in the present invention can guide the image light of the processing member and the reference member (or reference mark) to the position detection image pickup device. For example, it may be an optical fiber arranged to face the processing member at different angles. Moreover, although the camera was used as an image pick-up device in the said embodiment, the image pick-up device in this invention should just be the structure which can detect light, for example, may be a line sensor. In the above embodiment, the case where the present invention is applied to a wire bonding apparatus has been described. However, the present invention can be applied to various other bonding apparatuses such as a die bonding apparatus, a tape bonding apparatus, and a flip chip bonding apparatus. is there.

It is a perspective view which shows the principal part of the bonding apparatus which concerns on 1st Embodiment. It is a front view which shows the principal part of 1st Embodiment. It is explanatory drawing about irradiation of a reference pattern, (a) is an irradiation direction and the position of a tool, (b) is an example of a reference pattern, (c) and (d) are optical images of a tool irradiated with a reference pattern. is there. It is a block diagram which shows the control system of 1st Embodiment. It is a top view which shows the arrangement | positioning state of the tool in offset correction, the camera for position detection, and a reference member. It is explanatory drawing which shows the image in the attitude | position which made the tool adjoin to the reference member. It is explanatory drawing which shows the image in the attitude | position which made the position detection camera adjoin to the reference member. (A) thru | or (e) is explanatory drawing which shows the other structural example of a reference | standard pattern. It is a front view which shows the modification of an optical system. It is a perspective view which shows the principal part of 2nd Embodiment. A 3rd embodiment is shown, (a) is a front view showing an important section, and (b) is an optical image of a tool. It is explanatory drawing which shows the principal part of 4th Embodiment. (A) thru | or (e) is explanatory drawing which shows the image of the tool in 4th Embodiment. It is a perspective view which shows the principal part of 5th Embodiment. (A) thru | or (e) is explanatory drawing which shows the image of the tool in 5th Embodiment.

Explanation of symbols

  1 XY table, 2 bonding head, 3 bonding arm, 4 tool, 4a axis, 7 position detection camera, 7a optical axis, 11 reference base, 18, 130 prism, 15, 16 laser diode, 30 reference member, 30a axis Heart, 50 correction lens.

Claims (6)

A position detecting image pickup device for picking up an image of the bonding component, a tool for offsetting the position detecting image pickup device for processing the bonding component, and an XY table for integrally moving the position detecting image pickup device and the tool. In the provided bonding apparatus,
An optical path changing means for guiding the image light of the tool to the position detection image pickup device disposed directly above;
A reference mark provided on the upper surface of the optical path changing means, and a reference mark arranged at a reference position associated with a reference position in the plane of the XY table;
An X-direction reference pattern and a Y-direction are arranged at a position associated with a reference position in the plane of the XY table and have a predetermined inclination angle with respect to the plane of the XY table toward a tool having an axis perpendicular to the XY plane. A light source for projecting a reference pattern, wherein a deviation amount in the X direction between an imaging reference position provided at a predetermined position in the longitudinal direction of the tool and a reference position is set to be the same as the X direction offset amount, and the Y direction A light source whose deviation is set to zero,
An arithmetic and control unit for obtaining an offset amount in the XY plane;
With
The arithmetic and control unit
A measurement value obtained by imaging a reference mark with a position detection image sensor and measuring a positional relationship between the reference mark and the position detection image sensor;
Measurement value obtained by measuring the positional relationship between the reference mark and the tool on the basis of the imaged tool outline and the reference pattern on the tool, by imaging the tool with the position detection imager through the optical path changing means. When,
The amount of deviation between the imaging reference position and the reference position when the reference pattern on the tool is imaged by the position detection imaging device via the optical path changing means;
An offset amount in the XY plane is obtained based on the above. The bonding apparatus according to claim 1,
The light source projects the X-direction reference pattern and the Y-direction reference pattern from the upper side to the lower side, with the direction toward the upper surface of the optical path changing means as the upper side. The bonding apparatus according to claim 1,
The light source projects the X-direction reference pattern and the Y-direction reference pattern from the lower side to the upper side, with the direction facing the upper surface of the optical path changing means as the upper side. A position detecting image pickup device for picking up an image of the bonding component, a tool for offsetting the position detecting image pickup device for processing the bonding component, and an XY table for integrally moving the position detecting image pickup device and the tool. In the provided bonding apparatus,
An optical path changing means for guiding the image light of the tool to the position detection image pickup device disposed directly above;
A reference member disposed at a reference position associated with a reference position in the plane of the XY table;
The tool-side reference pattern is placed at a predetermined inclination angle with respect to the plane of the XY table toward the tool having an axis perpendicular to the XY plane and arranged in a position associated with the reference position in the plane of the XY table. A light source for projecting a reference member side reference pattern to a reference member erected with respect to a plane,
An arithmetic and control unit for obtaining an offset amount in the XY plane;
With
The arithmetic and control unit
The reference member and the tool are imaged by the position detection imager via the optical path changing means, and the reference member contour, the reference member side reference pattern on the reference member, the tool contour, and the tool side reference on the tool Based on the pattern, a measured value that measures the positional relationship between the reference member and the tool,
A measurement value obtained by imaging the reference member with the position detection image sensor and measuring the positional relationship between the reference member and the position detection image sensor;
An offset amount in the XY plane is obtained based on the above. A position detecting image pickup device for picking up an image of the bonding component, a tool for offsetting the position detecting image pickup device for processing the bonding component, and an XY table for integrally moving the position detecting image pickup device and the tool. In the provided bonding apparatus,
An optical path changing means for guiding the image light of the tool to the position detection image pickup device disposed directly above;
A reference mark provided on the upper surface of the optical path changing means, and a reference mark arranged at a reference position associated with a reference position in the plane of the XY table;
A light source that is arranged at a position associated with a reference position in the plane of the XY table and emits ring-shaped light having a predetermined inclination angle with respect to the plane of the XY table with respect to the axis of the tool perpendicular to the XY plane. A light source that projects a reference pattern on the entire circumference of the tool at an imaging reference position provided at a predetermined position in the longitudinal direction of the tool;
An arithmetic and control unit for obtaining an offset amount in the XY plane;
With
The arithmetic and control unit
A measurement value obtained by imaging a reference mark with a position detection image sensor and measuring a positional relationship between the reference mark and the position detection image sensor;
Measurement by measuring the positional relationship between the reference mark and the tool based on the contour of the imaged tool and the reference pattern on the tool based on the image of the tool captured by the position detection imager through the optical path changing means Value and
An offset amount in the XY plane is obtained based on the above. In the bonding apparatus according to claim 5,
The light source projects a reference pattern from the lower side to the upper side, with the direction toward the upper surface of the optical path changing means as the upper side.

Images