JP2010185784A - Substrate inspection apparatus and method of aligning the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate inspection apparatus following a change in the electrical inspection PASS position of a substrate. <P>SOLUTION: The substrate inspection apparatus 1 includes an alignment function for inspecting a wiring pattern 21 of a substrate 2 including substrate positioning marks 201, 202. The substrate inspection apparatus 1 includes: a probe 34; an inspection tool 3 that includes tool positioning marks 311, 312 provided on a probe holding plate 35 and is mounted on the substrate inspection apparatus 1; an inspection tool moving section 162 for moving the inspection tool 3; a press mechanism 166; a substrate holding section 33 for holding the substrate 2; and a control section 11 for recognizing the substrate positioning marks 201, 202 and the tool positioning marks 311, 312 in a pressed state by a camera 15 and for aligning the substrate 2 and the inspection tool 3. The control section 11 statistically calculates the difference between the optical alignment position and a position conforming to an electrical inspection to align and inspect based on the difference. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a substrate inspection apparatus having an alignment function for inspecting a wiring pattern by contacting a contact with a wiring pattern formed on a printed wiring board.

Here, a mounting board on which ICs, capacitors, and resistors are already mounted is referred to as a circuit board, and a bare board on which ICs, capacitors, resistors, and the like are not yet mounted is referred to as a printed wiring board.
And this invention is not restricted to a printed wiring board, For example, various substrates, semiconductor wafers, such as a flexible substrate, a multilayer wiring board, an electrode plate for a liquid crystal display and a plasma display, a package substrate for semiconductor packages, a film carrier, etc. It can be applied to the inspection of electrical wiring formed on the board. In this specification, these various wiring boards are collectively referred to as “substrates”.

  In Patent Document 1, the reference mark on the substrate and the reference hole of the inspection jig are read with a camera in a state where the tip of the contact of the inspection jig is in contact with the inspection point of the wiring pattern to be inspected on the substrate. A configuration is disclosed in which the displacement of these positions is detected, the contact is released, the displacement is corrected, and the contact is re-contacted for inspection.

  In Patent Document 2, a pair of cameras are inserted between the surface of the substrate and the surface on which the contact of the inspection unit is implanted, and the positioning mark on the surface of the substrate and that of the inspection unit are inserted by the pair of cameras. A configuration is disclosed in which the positioning marks on the surface are observed at the same time, and if they are not on the same optical axis, it is assumed that there is a displacement, and the inspection jig is moved to correct the displacement.

Patent Document 3 is a main camera that reads a table positioning mark to determine a reference for coordinates, and further reads a substrate positioning mark to recognize the position of a substrate, and further, a jig is formed by an auxiliary camera held on a transfer table. A configuration for recognizing the position of an inspection jig by reading a positioning mark is disclosed. According to it, using the fact that the positional relationship between the main camera and the auxiliary camera is the intrinsic constant of the substrate inspection device, the positional relationship between the substrate and the inspection jig is calculated to calculate the positional deviation and to correct it. Thus, the alignment of the inspection point on the substrate and the contact of the inspection jig is achieved. And the function which detects and correct | amends a position shift in the state contact | abutted described in said patent document 1 is also disclosed.
In the alignment method according to the above patent document, the substrate positioning mark and the inspection jig positioning mark are commonly used, and the camera of the main body of the substrate inspection apparatus reads each mark, and the substrate, the inspection jig, The positional deviation is corrected by recognizing the relative positional relationship.

  In this method, the position of the inspection jig can be recognized and the optical alignment can be performed more easily and accurately than the method in which only the positioning mark on the substrate is read without positioning the inspection jig. it can.

Noto 2517277 gazette JP-A-5-302952 Japanese Patent No. 3313085

  However, in the alignment methods disclosed in Patent Documents 1 to 3, the position where the inspection point of the substrate that easily produces PASS suitable for electrical inspection is aligned with the contact of the inspection jig at a position slightly shifted from the aligned position. May exist. Therefore, the vicinity of the position where the optical alignment has been performed is searched to check the conforming position of such an electrical inspection. If the conforming position is different from the position of the optical alignment, the conforming position is It was necessary to correct the inspection data of the substrate inspection apparatus so that the alignment target position was reached.

The difference between the optical position of this optical alignment and the matching position suitable for electrical inspection is slight, but differs depending on the individual inspection jig. Yes, there was a case where PASS did not come out, and it was corrected by searching for an appropriate position.
Therefore, when using a plurality of board inspection devices and a plurality of inspection jigs, it is necessary to correct the deviation from the compatible position each time the combination is changed. The setup time of was long.
From the above viewpoint, it is preferable to store and read out the correction value of the error of each inspection jig.

In addition, the matching position depends on the production lot of the substrate and the like, but may be slightly different. This is considered to be a succession of the characteristic differences and conditions of the plurality of substrate manufacturing apparatuses in the previous process.
The present invention relates to a substrate inspection apparatus for recognizing the relative position between a substrate and an inspection jig at the time of electrical inspection pressing, and statistically processes the relative position based on the pass / fail judgment result and uses it as a conforming position for inspection. It is.

  The invention of claim 1 is a substrate inspection apparatus having an alignment function for inspecting a wiring pattern by bringing the probe into contact with a plurality of inspection points on the wiring pattern of the substrate having a substrate positioning mark. A probe holding plate for holding the substrate, an inspection jig mounted on the substrate inspection apparatus with a jig positioning mark provided on the probe holding plate, and the substrate inspection apparatus for moving the inspection jig Inspection jig moving unit, pressing mechanism, substrate holding unit for holding the substrate, control unit for recognizing the substrate positioning mark and jig positioning mark with the camera in the pressed state, and aligning the substrate with the inspection jig The control unit statistically calculates a difference between the optical alignment position and a position suitable for electrical inspection, and performs an inspection by performing alignment based on the difference.

According to a second aspect of the present invention, in the substrate inspection apparatus according to the first aspect, the statistical calculation uses position data for the latest non-defective product determination.
According to a third aspect of the present invention, in the substrate inspection apparatus according to the first aspect, the camera is mounted on an inspection jig.
According to a fourth aspect of the present invention, in the substrate inspection apparatus according to the first aspect, the substrate holding portion includes a plurality of substrate holding pins mounted on a probe holding plate of a lower inspection jig.

  The invention according to claim 5 is an alignment method for a substrate inspection apparatus for inspecting a wiring pattern by bringing the probe into contact with a plurality of inspection points on the wiring pattern of the substrate having a substrate positioning mark. A probe holding plate for holding, an inspection jig mounted on the substrate inspection apparatus with a jig positioning mark provided on the probe holding plate, an inspection jig moving unit for moving the inspection jig, A press mechanism, a substrate holding unit for holding the substrate, a substrate positioning mark and a jig positioning mark are recognized by the camera in a pressed state, and a control unit for aligning the substrate and the inspection jig is provided. A substrate inspection apparatus alignment method characterized by statistically calculating a difference between the optical alignment position and a position suitable for electrical inspection, and performing an inspection based on the difference.

According to a sixth aspect of the present invention, in the alignment method for a substrate inspection apparatus according to the fifth aspect of the present invention, the statistical calculation uses position data for the latest non-defective product determination.
By providing these inventions, the above problems can be solved.

According to the first, second, fifth, and sixth aspects of the present invention, it is possible to follow even if the adaptable position where PASS is likely to occur at the time of electrical inspection changes depending on the production lot of the substrate. Since data is sampled from a plurality of substrates, since the latest matching position, the probability of PASS is high, the reliability of quality determination is increased, and productivity is improved.
Further, when searching for an appropriate position, since the latest PASS position is automatically recorded and statistical calculation is performed, it is easy and accurate to converge to the appropriate position. It also shortens the setup time.

According to the invention of claim 3, since the camera is mounted on the inspection jig, even if the inspection jig moves for alignment, the camera also moves together, so the field of view does not move, and the substrate positioning mark Can move and recognize. Since the relative position between the substrate and the inspection jig during the actual inspection in the pressed state can be sampled, the position correction is accurate.
According to the invention of claim 4, since the substrate holding pin is implanted in the probe holding plate of the lower inspection jig and the tip is inserted and locked into the reference hole of the substrate, the lower surface of the substrate has a simple structure. Can be mechanically aligned. The upper inspection jig on the upper surface is in a position where alignment of the previous inspection is completed, and it can be expected that PASS is issued at the first press. This contributes to shortening the inspection time.

As described above, even if the difference between the optical alignment position and the electrical inspection conforming position changes due to the manufacturing characteristics of the board, the conforming position is determined by statistical processing to improve inspection reliability. Can do.
A substrate inspection apparatus according to a preferred embodiment of the present invention will be described below with reference to the accompanying drawings.
In each attached drawing, the thickness, length, shape, interval between members, etc. are enlarged, reduced, deformed, simplified, etc. for easy understanding.

It is a front view which shows schematic structure of the board | substrate inspection apparatus which concerns on one Example of this invention. In addition, the part shown with the dotted line shows the part arrange | positioned inside. It is a flowchart which shows the basic operation | movement of the test | inspection of the board | substrate inspection apparatus of FIG. (A) shows the camera image at the time of the 1st press in the board | substrate inspection apparatus of FIG. 1, (b) shows the camera image after the optical alignment in the board | substrate inspection apparatus of FIG. 1, (c) shows FIG. The camera image of the conformity position of the electrical inspection in the board | substrate inspection apparatus of this is shown. An example of moving the conformity position of the electrical inspection is shown. The block diagram of the board | substrate inspection apparatus of FIG. 1 is shown. It is a flowchart which shows the basic operation | movement of the test | inspection of the conventional board | substrate inspection apparatus.

[Schematic configuration of substrate inspection equipment]
FIG. 1 is a front view showing a schematic configuration of a substrate inspection apparatus 1 according to an embodiment of the present invention. The figure shows a lower inspection jig 32 that holds the substrate 2 and contacts the lower side surface, an upper inspection jig 31 that contacts the upper side surface of the substrate 2, and an inspection jig holding each inspection jig 3. The mechanical part 16 is composed of a machine main body 161 by a pressing mechanism 166 and an XYθ moving part 162 for driving the part 163 and the inspection jig holding part 163.

The lower inspection jig 32 has a plurality of support columns 36 on a jig base plate 37, and a probe holding plate 35 is connected thereon. On the probe holding plate 35, a plurality of probes 34 that are contact-connected to the inspection points 22 for inspecting the wiring pattern 21 of the substrate 2 are implanted at corresponding positions and connected to the electrical inspection unit 13.
Four or more substrate holding pins 331 are implanted at positions corresponding to the reference holes 23 of the substrate 2, and the tips of the substrate holding pins 331 engage with the reference holes 23 of the substrate 2 to hold the substrate 2. The substrate holding part 33 is configured. The substrate holding pins 331 are configured to be accommodated in the inner direction of the lower substrate inspection jig 32 when pressed from above. The lower side is mechanically aligned at the time of manufacture.

In the upper inspection jig 31, a plurality of support columns 36 are erected on the jig base plate 37 and the probe holding plate 35 is connected to the tip. Similar to the lower inspection jig 32, jig positioning marks 301 and 302 are implanted on the probe holding plate 35 at positions corresponding to the plurality of probes 34 and the two substrate positioning marks 201 and 202.
The jig positioning marks 301 and 302 are made of ring-shaped metal, and it is preferable for the camera 15 to recognize the position that the same surface treatment as the substrate positioning marks 201 and 202 is performed.
A camera rail 313 for detachably mounting the camera 15 is fixed to the jig base plate 37 on the upper inspection jig 31, and the substrate positioning marks 201 and 202 and the jig positioning marks 301 and 302 are photographed coaxially. Can do. Even if the upper inspection jig 31 moves according to the XYθ moving unit 162, the jig positioning marks 301 and 302 do not move, and the substrate positioning marks 201 and 202 appear to move relatively.
When the inspection jig 3 is mounted on the inspection jig holding portion 163, the positioning pin 164 that determines the mechanical position passes coaxially through the positioning holes at the fixed positions of the inspection jig holding portion 163 and the jig base plate 37. ing. Although not shown, the inspection jig holding portion 163 has a mechanism for holding the jig base plate 37 and fixes the inspection jig 3.

  The wiring pattern 21 of the substrate 2 in the figure has two inspection points 22 on the upper side and one inspection point 22 on the lower side. Since there is an error between the substrate positioning marks 201 and 202 (pattern) and the reference hole 23 (machined hole), alignment is required for each substrate 2 when the inspection point 22 becomes small.

In the block diagram of the substrate inspection apparatus in FIG. 5, the control of the apparatus will be described.
In the apparatus of one embodiment, the electrical inspection unit 13 is brought into contact with the inspection point 22 of the substrate 2 through the inspection jigs 31 and 32 with the control unit 11 as the center to perform the conduction and insulation inspection of the substrate 2.
The mechanism unit 16 includes a machine body unit 161, an XYθ moving unit 162, a press mechanism 166, an inspection jig holding unit 163, and the like. The camera 15 is connected to the image processing unit 14, converted into X and Y data, and recognized by the control unit 11.
The operation panel 12 functions as a means for dialogue between the operator and the board inspection apparatus 1.

In FIG. 2, the basic operation of the inspection of the substrate inspection apparatus 1 will be described.
First, in step 51, the substrate 2 is set on the substrate holding portion 33 on the substrate holding pins 331 of the lower inspection tool 32. Next, in step 52, pressing is started from the operation panel 12.
In step 53, when the press operation is completed and the substrate 2 and the inspection jig 3 are in contact with each other, the electrical inspection unit 13 performs a continuity / insulation inspection to determine pass / fail. At the same time, in step 531, the camera 15 captures the substrate positioning marks 201 and 202 and the jig positioning marks 301 and 302 and reads an image.
When the inspection is completed, the press is released at step 54. At the same time, the image read in step 541 is processed, and the PASS position is statistically processed.
In step 55, if it is a non-defective product determination, the determination is confirmed and the substrate 1 is discharged in step 57.

If a defect is determined, the substrate 2 is a good product, but the alignment is poor and a defect determination may be made. Next, the position is corrected in step 56 and aligned to the conformity position of the electrical inspection, and then reinspected. Therefore, the process returns to the press drive in step 52 described above. The operation time for the position correction in step 56 is short and is completed within the operations of the press release drive in step 54 and the press drive in step 52, and does not affect the inspection time.
Then, in step 53, continuity and insulation are inspected again, and pass / fail is determined. Even if the determination result is defective, the alignment is performed. Therefore, it is determined in step 55 that the substrate 2 is defective, and the substrate in step 57 is unloaded. The above is the flow of the alignment operation of the present invention.

The basic operation of this inspection is called fail retry (re-inspection at the time of failure), and it is a flow to re-confirm the quality by aligning and re-pressing at the time of failure determination. If there is no alignment, the judgment time is fast. Since the PASS position is statistically processed, there is a feature that the reliability of the pass / fail judgment is high.
The conventional improvement of the present invention is that statistical processing of the PASS position in step 541 is added, and the position data at the time of PASS is used statistically for the matching position.

In FIG. 3, a camera image at the time of inspection (contact) will be described.
In FIG. 3A, the first press drive in step 52 is completed, and the two cameras 15 are mounted on the upper inspection jig 31 in the image of the camera 15 at the time of continuity and insulation inspection in step 53, and the probe holding plate 35. The jig positioning marks 301 and 302 and the substrate positioning marks 201 and 202 of the substrate 2 are simultaneously imaged.
The outer frame of the figure is the CCD imaging range of the camera 15. The jig positioning mark 302 on the right side of the drawing is press-fitted and fixed in the hole of the probe holding plate 35. Processing and assembly are performed so that the center inside the ring and the substrate positioning mark 202 are coaxial, but the deviation of the center of each mark is a positional deviation in the X and Y-axis direction as ΔX2 = (202x−302x). ) And ΔY2 = (202y−302y). Similarly, the left side of the figure can be calculated as ΔX1 = (201x−301x) and ΔY1 = (201y−301y).

FIG. 3B is an image of the camera 15 when the press is performed for the second time after aligning the jig positioning marks 301 and 302 with the centers of the substrate positioning marks 201 and 202. The center of each mark is coincident. This position is the design optical alignment position (optical position), but there may be a suitable position where PASS suitable for electrical inspection is likely to appear in this area. This is shown in FIG. 3C.
Aj1 (AjX1, AjY1) and Aj2 (AjX2, AjY2) are used as the correction positions as correction amounts from the centers of the jig positioning marks 301, 302.

  The main cause of the deviation from the optical position is an error in manufacturing the jig positioning marks 301 and 302 of the upper inspection jig 31 and the probe 34, and the optical position as an individual correction amount of the upper inspection jig 31. It is preferable to add. It can be used by writing to and reading from the storage means.

FIG. 4 shows how the PASS conforming position may change depending on the production lot of the substrate 2, etc., with respect to the X-axis component. The center of PASS has moved from AjXmax to AjXmin. In such a case, it is more efficient to change and track the target of the matching position in accordance with the characteristics of the substrate 2 currently inspected without fixing it.
The present invention utilizes the fact that the position reading and the inspection determination of the substrate 2 and the inspection jig 31 are performed in the same state of step 53, and stores a plurality of positions at the time of PASS determination, and statistical processing is performed to determine an appropriate position. Recalculate. Then, the recalculation position is targeted.

As a specific example, the number of samples n = 10, and the conforming position is corrected to the positions of the ten good products closest to the substrate 2 being inspected. When this function is effective, even if the characteristics of the substrate 2 change from AjXmax to AjXmin in FIG.

  In the flowchart showing the basic operation of the conventional inspection in FIG. 6, the basic mechanical operation is the same, and the correction amount may be set as a fixed value by the position correction in step 66. However, the center of the PASS is not changed thereafter, and it is necessary for the operator to regularly scan the periphery to take action, which is a burden on the work.

  As another embodiment, when the vicinity of the optical position described above is scanned to search for an appropriate position, the PASS position is automatically stored and statistical processing is performed, so that it is easy and accurate to converge to the appropriate position. And the setup time will be faster.

The statistical processing of the matching position will be described in detail. Optical alignment is performed by two cameras 15 at two positions of the substrate 2 and the upper inspection jig 31 (ΔX1, ΔY1) and (ΔX2, ΔY2) Converted from FIG. 3A to a plane displacement (ΔX, ΔY, Δθ). Since the correction amount is calculated in this manner, when the upper inspection jig 31 is corrected by driving the XYθ moving unit 162 from the control unit 11, the respective planes can be matched (X0, Y0, θ0) as shown in FIG. 3B. .
Next, there are cases where there is a suitable position for electrical inspection where PASS is likely to occur. Therefore, if the suitable position is found at a position other than the optical position by scanning the periphery and searching for the suitable position, correction values (AjX, AdY, (Adθ) FIG. 3C is set and set as a target value.

Even if the correction values (AjX, AdY, Adθ) may change depending on the production lot of the substrate 2, the present invention sets the correction values (AjX, AdY, Adθ) to the average of the n most recent PASSes from the fixed value. Therefore, the correction values (AjX, AdY, Adθ) are automatically rewritten according to the latest characteristics of the substrate 2.
[Other Embodiments]

In the description of FIG. 1 described above, only the single-side alignment on the upper side has been described. However, the XYθ moving unit 162, the camera 15, and the jig positioning mark are also arranged on the lower side, and the substrate holding unit 33 is moved. Both-side alignment is also possible.
Further, although the moving part of the inspection jig 3 of the mechanism part 16 is the press mechanism 166 and the XYθ moving part 162 from the bottom, the order of the mechanical configuration of each function may be changed for the convenience of design.
Moreover, although the jig positioning marks 301 and 302 are implanted in the probe holding plate 35, they may be separately provided in the inspection jig 3 as long as the positional relationship with the probe 34 is fixed.
Further, although metal rings are preferable as the jig positioning marks 301 and 302, holes for the probe holding plate 35 may be used as long as the position can be recognized by the camera 15.

A function for selecting whether to enable or disable the statistical processing function of the PASS position in step 541 may be added. Conventional functions may be sufficient.
The function of the present invention can be improved by modifying a control method such as a control program in the conventional apparatus as long as the configuration shown in FIG.

As mentioned above, although several embodiment of the board | substrate inspection apparatus 1 which concerns on this invention was described, this invention is not restrained by those embodiment, The addition, deletion, modification, etc. which those skilled in the art can make easily are performed. It should be understood that the present invention is included in the present invention, and that the technical scope of the present invention is defined by the description of the appended claims.

DESCRIPTION OF SYMBOLS 1 .... Board inspection apparatus 11 ... Control part 13 ... Electrical inspection part 15 ... Camera 162 ... XYXY movement part 163 ... Inspection jig holding part 166 ... Press mechanism 2 ... Substrate 201, 202 ··· Board positioning mark 21 ··· Wiring pattern 22 ··· Inspection point 23 ··· Reference hole 3 ··· Inspection jig 301 and 302 ··· Jig positioning mark 31 ··· Upper inspection Jig 32 ... Lower inspection jig 33 ... Substrate holding part 331 ... Substrate holding pin 34 ... Probe 35 ... Probe holding plate

Claims (6)

A substrate inspection apparatus having an alignment function for inspecting a wiring pattern by bringing a probe into contact with a plurality of inspection points on the wiring pattern of the substrate having a substrate positioning mark,
A probe holding plate for holding the probe, and an inspection jig mounted on the substrate inspection apparatus with a jig positioning mark provided on the probe holding plate;
The substrate inspection apparatus includes an inspection jig moving unit for moving the inspection jig, a press mechanism,
A substrate holder for holding the substrate;
A controller that recognizes the substrate positioning mark and the jig positioning mark with a camera in a pressed state, and aligns the substrate and the inspection jig;
The control unit statistically calculates a difference between the optical alignment position and a position suitable for electrical inspection, and performs alignment and inspection based on the difference.   2. The substrate inspection apparatus according to claim 1, wherein the statistical calculation uses position data of the latest non-defective product determination.   2. The substrate inspection apparatus according to claim 1, wherein the camera is mounted on an inspection jig in the previous period.   The substrate inspection apparatus according to claim 1, wherein the substrate holding portion includes a plurality of substrate holding pins attached to a probe holding plate of a lower inspection jig. An alignment method for a substrate inspection apparatus for inspecting a wiring pattern by bringing a probe into contact with a plurality of inspection points on the wiring pattern of the substrate having a substrate positioning mark,
A probe holding plate for holding the probe, an inspection jig provided with a jig positioning mark provided on the probe holding plate and mounted on the substrate inspection apparatus, and an inspection for moving the inspection jig A jig moving unit, a press mechanism, a substrate holding unit for holding the substrate, the substrate positioning mark and the jig positioning mark are recognized by a camera in a pressed state, and the substrate and the inspection jig are aligned. A control unit that
The control unit statistically calculates a difference between the optical alignment position and a position suitable for electrical inspection, and performs alignment and inspection based on the difference, thereby aligning the substrate inspection apparatus. .   6. The alignment method for a substrate inspection apparatus according to claim 5, wherein the statistical calculation uses position data for latest non-defective product determination.

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