JP3332001B2 - Recognition method of the tip of the contact probe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used as a probe pin, a socket pin, or the like, and recognizes a needle point of a contact probe for performing an electrical test by contacting a contact pin with each terminal of a semiconductor IC chip or a liquid crystal device. About the method.

[0002]

2. Description of the Related Art In general, a contact probe having a contact pin is used to make an electrical test by contacting a semiconductor chip such as an IC chip or an LSI chip or each terminal of an LCD (liquid crystal display). I have.

[0003] In recent years, as the integration density and miniaturization of IC chips and the like have increased, the pitch of contact pads, which are electrodes, has been reduced, and the pitch of contact pins has been required to be narrower. However, with a tungsten needle contact probe used as a contact pin, it has been difficult to cope with a multi-pin narrow pitch due to the limitation of the diameter of the tungsten needle.

On the other hand, for example, Japanese Patent Publication No. 7-820
No. 27 proposes a contact probe technique in which a plurality of pattern wirings are formed on a resin film, and the ends of these pattern wirings are arranged so as to protrude from the resin film and serve as contact pins. That is,
As shown in FIG. 4, the contact probe 1 has Ni (nickel) or N
It has a structure in which a pattern wiring 3 formed of an i-alloy is adhered, and the pattern wiring 3
Are projected to form contact pins 3a.
In this technology example, by using the contact pins 3a at the tips of the plurality of pattern wirings 3, the pitch of the pins is narrowed, and many complicated components are not required.

By the way, in order to arrange the contact pins of the contact probe so as to be able to contact the electrode pads of the semiconductor IC chip, for example, it is necessary to adjust the position so that the contact pins are aligned with the electrode pads. Therefore, generally, in order to adjust the position of the contact pin, the position of the stylus is recognized by image processing using an image reading device having a built-in CCD camera.

For example, when a conventional tungsten needle W is used as a contact pin, as shown in FIG. 5A, a contact portion W1 that actually contacts an electrode pad is formed on a plane and directly below. The illumination light L is radiated from directly below this, and as shown in FIG. 5B, the reflected light is photographed, and the contact obtained by performing the binarized image processing is obtained. By approximating the part W1 to a circle,
The center was recognized as the actual needle point position W2.

In the contact probe 1, when the position of the contact pin 3a is adjusted, the position of the needle point is recognized by similarly irradiating the illumination light from directly below and binarizing the image. Was.

The contact probe 1 is
As shown in FIG. 6, at the tip of the contact pin 3a, the corner at the position where the contact pin 3a actually comes into contact with the electrode pad is polished to form the identification surface 3b so that the tip of the contact pin 3a can be easily recognized. By doing so, a technique has been proposed in which reflected light can be reliably captured with a sufficient amount of light with respect to the illumination light L radiated from below to form an image, and binarization identification can be easily performed. .

[0009]

The above-mentioned conventional needle point recognition method has the following problems. That is, in the recognition of the tip of the contact probe 1, when the reflected light image from the polished identification surface 3b is binarized, the identification surface 3b actually has a perfect circular shape as shown in FIG. In addition, since it is not a perfect plane but a curved surface, the center when the contour is approximated as a circle cannot be said to be the needle tip, and if this position is recognized as the needle tip position, it will deviate from the actual needle tip position. There was a problem of misrecognition at the position. In addition, although only the tip of the needle is illuminated by various light sources (coaxial light, external illumination, etc.), there is a possibility that erroneous recognition may occur because the manner of light changes depending on the state of the tip of the needle (adhesion of dust, etc.).

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a needle tip recognition method for a contact probe which can accurately recognize a needle tip position without erroneous recognition. .

[0011]

The present invention has the following features to attain the object mentioned above. That is, in the method for recognizing the probe tip of the contact probe according to the first aspect, a plurality of pattern wirings are formed on the surface of the film, and the respective tips of the pattern wirings are arranged so as to protrude from the leading end of the film to form contact pins. A method for recognizing a needle tip of a contact probe, comprising irradiating illumination light to a tip portion of the contact pin supported in an inclined state with respect to an electrode pad to be inspected, and reflecting reflected light of the illumination light to a solid. The image of the contact pin is received by an image sensor, and the image of the contact pin is converted into a binarized image, and a tip position of the contact pin is detected based on a contour of the contact pin obtained in the binarized image. A technique of recognizing a position retracted by a predetermined distance from a position as a needle point to be brought into contact with the electrode pad is adopted.

In this method of recognizing the tip of a contact probe, the tip position of the contact pin is detected based on the contour of the contact pin obtained from the binarized image, and a predetermined position set in advance from the tip position is determined. Since the position receded by the distance is recognized as the needle tip position to be brought into contact with the electrode pad, the entire tip portion of the contact pin is recognized by the outline and the foremost position is accurately identified. The needle tip position is accurately recognized at a position set in advance from the tip end position.

Furthermore, the needle point recognition method of claim 1, wherein the contact probe, wherein the calculating a center line of the contact pins from the position of both sides of the contact pin in the binarized image, and the outline and centerline A technique is adopted in which the intersection of is set as the leading edge position.

In this method of recognizing the tip of the contact probe, the center line of the contact pin is calculated from the positions on both sides of the contact pin in the binarized image, and the intersection between the center line and the contour is set as the foremost position. In addition, the tip position can be easily detected and the tip position can be accurately recognized.

According to the second aspect of the present invention, the plurality of pattern wirings are formed on the surface of the film.
Each end of these pattern wiring is formed on the film
It is arranged in a protruding state from the tip and is used as a contact pin
A method of recognizing the tip of a contact probe,
Before being supported in an inclined state with respect to the electrode pad to be inspected
Illuminating the tip of the contact pin with illumination light;
The reflected light of light is received by the solid-state
Image is a binarized image, and the image obtained before the binarized image is obtained.
The contact pin based on the contour of the contact pin
Detect the foremost position of and set in advance from the foremost position
The position retracted by a predetermined distance is placed on the electrode pad.
It has a method of recognizing as a needle tip position to be contacted , sets a rectangular virtual box having a width corresponding to the width of the contact pin in advance, and sets the outline of the contact pin obtained in the binarized image. A technique is adopted in which a position where the contour on the tip end side of the contact pin is inscribed in the virtual box is set as the foremost position in a state where both sides of the contact pin are inscribed in the virtual box.

In this method of recognizing the needle point of a contact probe, a rectangular virtual box having a width corresponding to the width of the contact pin is set in advance, and the contact pin in the contour of the contact pin obtained from the binarized image is set. In the state where both sides are inscribed in the virtual box, the position where the contour on the tip side of the contact pin is inscribed in the virtual box is the foremost position, so the amount of calculation processing is small, and it is easy and accurate. The stylus position can be recognized.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a method for recognizing a stylus tip of a contact probe according to the present invention will be described with reference to FIGS. In these figures, reference numeral 10 denotes a probe device, and 11 denotes an image reading device.

FIG. 1 shows a probe apparatus 1 for carrying out a method for recognizing a probe tip of a contact probe according to this embodiment.
0 and the image reading device 11 are shown. The probe device 10 is a probe card for performing an electrical test on a semiconductor IC chip (object to be inspected) and the like.
The probe is attached to a prober (not shown) with the contact probe 1 attached to the lower surface of the mounting base 13.

In order to recognize the position of the tip of the contact probe 1, an image reading device 11 for adjusting the position of the contact pin 3a is disposed below the probe device 10. The image reading device 11 includes a CCD
(Solid-state imaging device) Built-in camera, contact pin 3a
, And binarized image processing of the photographed image to detect the tip position. In addition, the contact pin 3a has
Illumination light L from an unillustrated illumination light source is emitted.

Next, a method of recognizing a needle tip of a contact probe in the present embodiment will be described with reference to FIG.

Contact pin 3a of probe device 10
Then, illumination light L is emitted from an illumination light source, and the reflected light is photographed by the image reading device 11. At this time, the illumination light L is
Irradiation is performed obliquely from below the contact pin 3a so that the tip of the contact pin 3a is entirely illuminated.

As shown in FIG. 2, the image data captured by the image capturing device 11 is converted into a binary image by image processing as shown in FIG. 2, and the outline 3c of the contact pin 3a obtained from the binary image is added to the image. The tip position F of the contact pin 3a is detected based on this. This tip position F
Are 3d on both sides of the contact pin 3a in the contour 3c.
, The center line 3e of the contact pin 3a is calculated,
The intersection of the center line 3e and the contour 3c is detected as the foremost position F.

Further, only a predetermined distance l from the detected tip position F, that is, the distance l between the portion actually in contact with the electrode pad and the tip position F is calculated or measured. Then, the position retracted along the center line 3e by this distance 1 is recognized as the needle point position P to be brought into contact with the electrode pad. Thereafter, based on the recognized needle point position P, the needle point of the contact pin 3a and the electrode pad of the semiconductor IC chip are brought into contact with each other to perform an inspection.

Next, a second embodiment of the method for recognizing the tip of a contact probe according to the present invention will be described with reference to FIG.

The difference between the second embodiment and the first embodiment is that, in the first embodiment, the foremost position F is set to the contact pin 3.
Although it was detected as the intersection between the contour 3c of a and the center line 3e,
In the second embodiment, as shown in FIG. 3, a rectangular virtual box B having a width B1 corresponding to the width of the contact pin 3a is set in advance, and the outline of the contact pin 3a obtained in the binarized image is set. In a state in which both sides 3d of the contact pin 3a in 3c are inscribed in the virtual box B, the position where the contour 3c on the distal end side of the contact pin 3a inscribes in the virtual box B is defined as the foremost position F. .

That is, the virtual box B on the binarized image is obtained from the width of the contact pin 3a which is known in advance.
The width B1 is set and the inscribed position with the contour 3c is set as the foremost position F, so that the calculation processing for obtaining the center line 3e as in the first embodiment is not required, and the needle point can be easily and accurately set. The position P can be recognized.

The present invention also includes the following embodiments. That is, the needle point recognition method of the present embodiment is not only the needle position recognition when attached to the prober,
The present invention is similarly applied to a needle position check after assembling a contact probe to a probe device (probe card).

[0028]

According to the present invention, the following effects can be obtained. (1) According to the method for recognizing a needle point of a contact probe according to the first aspect, the foremost position of the contact pin is detected based on the contour of the contact pin obtained in the binarized image, and the leading edge position is detected in advance from the foremost position. Since the position retracted by the set predetermined distance is recognized as the stylus position to be brought into contact with the electrode pad, regardless of the reflected light intensity that greatly affects the surface shape of the contact pin, the position from the outline based on the binarized image is By detecting the tip position, the needle tip position can be accurately recognized without erroneous recognition.

Furthermore, according to the needle point recognition method of claim 1, wherein the contact probe, to calculate the center line of the contact pins from the position of both sides of the contact pins in the binarized image, the center line and the outline Since the intersection is set as the leading end position, the leading end position can be easily detected and the needle point position can be accurately recognized.

( 2 ) According to the contact probe tip recognition method of the second aspect , a rectangular virtual box having a width corresponding to the width of the contact pin is set in advance,
In a state where both sides of the contact pin in the contour of the contact pin obtained in the binarized image are aligned so as to be inscribed in the virtual box, the position where the contour on the tip side of the contact pin is inscribed in the virtual box is referred to as the foremost position. Therefore, the amount of calculation processing can be reduced, and the tip position can be easily and accurately recognized.

[Brief description of the drawings]

FIG. 1 is a sectional view of a position adjustment state showing a probe device and a photographing unit of an image reading device in a first embodiment of a contact probe needle tip recognition method according to the present invention.

FIG. 2 is a diagram showing a binarized image for explaining detection of a forefront position and recognition of a needle tip position in the first embodiment of the contact probe needle tip recognition method according to the present invention.

FIG. 3 is a diagram showing a binarized image for explaining detection of a forefront position and recognition of a needle tip position in a second embodiment of the contact probe needle tip recognition method according to the present invention.

FIG. 4 is a plan view showing a contact probe according to the present invention.

FIG. 5 shows a conventional example of a method for recognizing a needle tip of a contact probe according to the present invention, and is a side view of a contact pin when a tungsten needle is used and a diagram of a binarized image thereof.

FIG. 6 shows a conventional example of a method for recognizing a needle tip of a contact probe according to the present invention, and shows a side surface of a contact pin at the time of position adjustment when using a contact probe manufactured by plating by a photolithography method or the like. FIG.

FIG. 7 is a contact probe according to the present invention,
It is the side view and bottom view which show the contact pin of the contact probe manufactured by plating processing by the photolithography method etc.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Contact probe 2 Resin film 3 Pattern wiring 3a Contact pin 3c Outline 3d Both sides of contact pin 3e Center line of contact pin 11 Image reading device B Virtual box F Leading edge position of contact pin L Illumination light P Tip position of contact pin

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁷ Identification code FI H01L 21/66 G06F 15/62 405B (56) References JP-A-62-191743 (JP, A) JP-A-6-342833 ( (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01R 31/28-31/3193 G01B 11/00 G01B 11/24 G01R 1/06-1/073 G06T 7/00 H01L 21 / 66

Claims (2)

(57) [Claims] A plurality of pattern wirings are formed on a surface of a film.
Each end of these pattern wiring is formed on the film
It is arranged in a protruding state from the tip and is used as a contact pin
A method of recognizing a needle tip of a contact probe, which is supported in an inclined state with respect to an electrode pad to be inspected.
Illuminating light is applied to the tip of the contact pin, and the reflected light of the illuminating light is received by a solid-state imaging device to form the contour.
The image of the contact pin is defined as a binarized image, and the image of the contact pin is obtained based on the outline of the contact pin obtained in the binarized image.
Then, the foremost position of the contact pin is detected, and the contact pin is retracted from the foremost position by a predetermined distance set in advance.
The contacted position is a needle tip position for contacting the electrode pad.
Has a method of recognizing Te, wherein calculating a center line of the contact pins from the position of both sides of the contact pin in the binarized image, that the intersection between the outline and the center line and the leading edge position Characteristic needle contact recognition method for contact probes. 2. A method according to claim 1, wherein a plurality of pattern wirings are formed on the surface of the film.
Each end of these pattern wiring is formed on the film
It is arranged in a protruding state from the tip and is used as a contact pin
A method of recognizing a needle tip of a contact probe, which is supported in an inclined state with respect to an electrode pad to be inspected.
Illuminating light is applied to the tip of the contact pin, and the reflected light of the illuminating light is received by a solid-state imaging device to form the contour.
The image of the contact pin is defined as a binarized image, and the image of the contact pin is obtained based on the outline of the contact pin obtained in the binarized image.
Then, the foremost position of the contact pin is detected, and the contact pin is retracted from the foremost position by a predetermined distance set in advance.
The contacted position is a needle tip position for contacting the electrode pad.
Setting a rectangular virtual box having a width corresponding to the horizontal width of the contact pin in advance, and both sides of the contact pin in the contour of the contact pin obtained in the binarized image A method of recognizing a needle point of a contact probe, wherein a position at which a contour on a tip end side of a contact pin is inscribed in a virtual box is set as the foremost position in a state where is fitted so as to be inscribed in the virtual box.