JPH0743384A - probe - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a probe capable of ensuring a constant contact pressure and a stable pitch interval, and flexibly responding to a demand for a narrow pitch. [Structure] Reference numeral 2 has a step portion at one end in the length direction, and 21 is provided so as to project in the width direction on the side surface of the horizontal portion of the step portion. 1 has a plurality of conductor patterns connecting one end and the other end in the length direction on one side face at a predetermined interval in the width direction, and 13 is formed at one end of each conductor pattern, while the other side face has 15 ends. The part is attached to the side surface of the second part so as to be aligned with the tip position of the horizontal part. No. 3 has one end in the length direction of 15 and the other half faces 13
Is attached to the vertical portion of the step portion at 4 so that a constant pressing force is generated by abutting against 21 and curving toward the horizontal portion in a state where is not in contact with the DUT. Simultaneously with being pressed against the test object, the intermediate part is separated from 21 and the contact pressure with the test object is maintained at a constant value by the applied pressure. The contact pressure of each 13 is made uniform by 5 and 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe used for measuring electrical characteristics of a high density electronic device, and more particularly to improvement of a probe in which so-called stylus is arranged in a horizontal row.

[0002]

2. Description of the Related Art In a conventional probe, as shown in FIG. 7 (a) and FIG. 8 (a), for example, a large number of metal wires are embedded in a row in the width direction of a probe main body 51 at equal intervals in a row. one end of the line (in the drawing the left) a so-called probe (52 ₁ to 52 _n)
The other end (right side in the figure) is used as a lead (53 _{1 to} 53 _n ) for connecting to the measuring device, and the stylus has a hook-like shape (Fig. 7 (a)) or a stick needle. Shape (Fig. 8
There are various types such as (a)).

This probe is shown in, for example, FIG. 7 (b) and FIG.
As shown in (b), the upper end of the probe main body 51 on the side of the connecting lead 53 is rotatably supported, and a large number of stylus 52 are integrally swung in the direction of the arrow shown in FIG. The tip is pressed against the corresponding electrode 55 of the device under test 54, and the connecting lead 53 is connected to the measuring device to be used for various tests of the device under test 54.

The DUT 54 is, for example, a liquid crystal panel having a high density, a thermal head of a FAX or a thermal copying machine, etc., but since the number of electrodes is considerably large, a plurality of probes are actually arranged in parallel. They are installed and rotated in parallel.

Therefore, in this type of probe, the tip position of each stylus is adjusted and set so as to be on the same plane, and each stylus has a predetermined length in order to ensure a predetermined contact pressure due to elastic force. However, since the DUT 54 is a high-density electronic device such as a high-density liquid crystal panel, the metal wire to be the stylus is extremely thin,
Since it is necessary to arrange them in a horizontal row at a narrow interval of m or 200 μm, assembly work such as attachment processing to the probe main body, processing of the needle part of the stylus, alignment to make the tip position on the same plane Are all done manually under a microscope.

[0006]

The above-mentioned conventional probe of the type in which the so-called stylus is arranged in a horizontal row has the following problems. First, the alignment of the tip position of the stylus and the processing accuracy of the stylus part tend to vary, which makes the elastic force of each stylus different and makes it difficult to maintain a uniform contact pressure. It is difficult to make the characteristics of the probes the same, but in the conventional assembly structure, there is no solution other than careful assembly of the stylus evenly, and the spacing between the stylus is not fixed. The assembly work is very complicated and troublesome because it requires careful handling so that the fine stylus is not deformed or brought into contact with each other in order to keep it constant. Is difficult to reduce.

Further, as shown in FIGS. 7C and 8C, since the stylus 52 has elasticity, the tip of the stylus 52 touches down on the surface of the electrode 55 of the DUT 54. At this time, there is a tendency that the electrode surface slides in the direction of the arrow and bites into it to obtain contact, and therefore, the electrode surface of the test object is often scratched, and improvement is desired.

Further, as can be inferred from FIGS. 7 and 8,
Since the stylus is likely to be plastically deformed or abnormally deformed, there is also a problem that long-term use is difficult unless a periodic inspection is performed and the damaged portion is repaired.

In addition, with the progress of high-density technology, it has become necessary to provide probes in which the stylus is arranged at intervals of 100 μm or less. However, since the stylus requires a predetermined length, it becomes adjacent when the interval becomes narrow. An increased risk of short circuit between the stylus of the
Due to the fact that it is difficult to manually manufacture the stylus at such narrow intervals because there are variations in the material and processing accuracy of the metal wire to be the stylus, the conventional probe structure has a
There is also a problem that it is not possible to meet the demand for a narrow interval of μm or less.

The present invention has been made in view of the above problems, and an object thereof is to easily ensure a constant contact pressure and a stable arrangement interval, and to prevent damage to a test object and a stylus. It is an object of the present invention to provide a probe that can reduce damage to the probe, can be manufactured at low cost by facilitating manufacturing and handling, and can flexibly cope with narrow array intervals.

[0011]

In order to achieve the above object, the probe of the present invention has the following constitution. That is, the probe of the present invention is a stylus in which a plurality of first protruding electrodes capable of contacting the terminals of a device under test in a one-to-one correspondence are formed on one side surface and an elastic body for stabilizing the contact is attached to the other side surface. A plate-shaped circuit portion having a conductor pattern connected to the plurality of first protruding electrodes in a one-to-one correspondence with the tip portion at one end; and the elastic body when the first protruding electrodes contact a device under test. A pressurizing mechanism that engages with the first protruding electrode to apply a constant pressing force to the first protruding electrode; and an offset mechanism that causes the pressing mechanism to form the constant pressing force before the first protruding electrode contacts the DUT. And; are provided.

[0012]

Next, the operation of the probe of the present invention constructed as described above will be described. The plurality of first protrusion electrodes at the tip of the stylus correspond to the conventional stylus made of a large number of metal wires arranged in one horizontal line, but are offset before the plurality of first protrusion electrodes are brought into contact with the DUT. When a constant pressurizing force is formed in the pressurizing mechanism by the mechanism and a plurality of the first protruding electrodes are brought into contact with the DUT, the constant pressurizing force by the pressing mechanism is applied to the first protruding electrode via the elastic body. In addition, all of the first protruding electrodes are brought into contact with the corresponding terminals of the device under test with a stable contact pressure.

Therefore, it is possible to secure the reliability of contact without causing variations as in the conventional case. In addition, since the change in the pressure applied to the DUT during pressurization can be reduced by the offset mechanism, the damage given to the electrode surface of the DUT can be significantly reduced, and the protruding electrodes are less likely to be damaged.

Further, since the array interval of the protruding electrodes can be set at an arbitrary interval and with high accuracy by a known printing technique, a constant and stable array interval can be easily secured, and the flexible array is flexible to meet the requirement of a narrow array interval. Can handle.

Since it can be manufactured simply and uniformly without the need for assembling under a microscope as in the conventional case, and the handling is very simple without using extra nerves, it is possible to reduce the cost. Is possible.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a probe according to an embodiment of the present invention. In FIG. 1, the probe has a flexible printed circuit board 1, a probe body 2 and a leaf spring 3 as main constituent elements.

Although the flexible printed circuit board 1 is a plate-shaped circuit portion, as shown in FIG. 2, a conductive film such as a copper foil formed on one side surface (one surface) of the flexible film 11 made of polyimide resin or the like is etched. A plurality of conductor patterns 12 are formed at predetermined intervals in the width direction to connect one end (left side in the drawing) and the other end in the length direction to each other. (First) protruding electrode 1
3 is formed, and the (second) protruding electrode 14 is similarly formed on the other end.

The bump electrode, which is also called a gold dot, is formed as follows. Protruding electrode 13
By exposing only the tip portion 15 and the portion where the protruding electrode 14 is formed and masking the other portion with photoresist or the like, gold plating is applied to the exposed portion, or by the wire bonding method used when forming bumps on the IC wafer, The protruding electrodes 13 and 14 are formed.

Next, the probe main body 2 has a width substantially equal to that of the flexible printed circuit board 1 and a step portion is formed at one end in the longitudinal direction (left side in the figure), and a horizontal portion facing a vertical portion of the step portion. Ridge-shaped offset bar 2 continuous in the width direction at the tip of the side surface of the
No. 1 is projected. The offset bar 21 functions as an offset mechanism.

The flexible printed circuit board 1 is attached to the side surface (lower side surface) of the probe main body 2 from the horizontal portion to the other end in the lengthwise direction, and the leaf spring 3 is attached to the vertical portion of the step portion with the adjusting screw 4. Raru The leaf spring 3 and the adjusting screw 4 constitute a pressing mechanism as a whole.

Specifically, the flexible printed board 1
Is a side surface (lower side surface) extending from the horizontal portion of the probe main body 2 to the other end in the lengthwise direction, the other side surface on which the conductor pattern 12 is not formed has a predetermined length including a portion where the protruding electrode 13 is formed. The position, that is, the end portion of the tip portion 15 in FIG. 2 is attached so as to be aligned with the tip position of the horizontal portion.

In short, the tip portion 15 at one end of the flexible printed circuit board 1 extends outward from the horizontal portion as a free end, and the protruding electrode 13 is provided on the lower surface thereof.
As shown in FIG. 4 and FIG. 4, the electrode 55 of the device under test 54 is brought into contact therewith and the same function as a conventional stylus is achieved.

An elastic body 5 made of silicon resin or the like is continuously attached to the upper surface of the free end portion 15 in the width direction. Therefore, the tip portion 15 constitutes a stylus tip portion.

The protruding electrode 14 at the other end of the flexible printed board 1 is connected to the flat cable 7 from the measuring device by the clamp 6 at the other end of the probe body 2 in the length direction.

Here, the flat cable 7 from the measuring device has a conductor pattern for connection formed on one side and an insulator on the other side. Originally, one side of the flat cable 7 is directly connected to the electrode of the DUT. It is used by connecting to the terminal.
Therefore, when connecting this to the electrode terminal of the DUT via the probe of the present invention, it is necessary to be able to connect to the flat cable 7 without inverting the circuit order of the DUT.

That is, in the probe of the present invention, the flexible printed circuit board 1 is attached to the lower surface of the probe body 2 with the conductor pattern 12 facing the electrode terminal side of the DUT.
If the flat cable 7 is connected horizontally to the conductor pattern 12, the flat cable 7 must have its connecting conductor pattern forming surface facing upward, and the circuit sequence will be reversed.

Therefore, in this embodiment, the flexible printed circuit board 1 is adopted as the plate-shaped circuit portion, and as shown in FIG. 1, the other end of the flexible printed circuit board 1 is bent to the other end side of the probe body 2 to stand upright. Raise and project electrode 14
The clamp 6 is provided at the height position of the flat cable 7, and the flat cable 7 is inserted into the clamp 6 from below with the connecting conductor pattern forming surface facing the flexible printed board 1 side.
The protrusions 14 are brought into pressure contact with the connecting conductor pattern of the flat cable 7 by the clamp 6 so that the circuit sequence is not reversed.

Therefore, when a rigid printed circuit board or the like is used as the plate-shaped circuit portion, the other end cannot be bent as in the present embodiment, so that the other end on the attachment surface side is projected through the through hole. The electrode 14 is provided and the flat cable 7 is horizontally connected.

Next, the leaf spring 3 has a width substantially equal to that of the flexible printed circuit board 1, one end in the length direction faces the other side surface (upper surface) of the tip portion 15 of the flexible printed circuit board 1, and a middle portion thereof. When the protruding electrode 13 is not in contact with the DUT 54, as shown in FIG.
The other end of the probe main body 2 so as to generate a constant offset pressure by abutting on 1 and bending toward the horizontal portion.
It is adjustably attached to the vertical part of the stepped part by adjusting screw 4.

As shown in FIG. 4, in the leaf spring 3, the projecting electrode 13 is pressed against the electrode surface of the device under test 54, and at the same time, the intermediate portion is separated from the offset bar 21 and the projecting electrode 13 is tested. The contact pressure on the body 54 is maintained at a constant value by the offset pressure. A rigid body 8 such as a metal plate is attached to the lower surface of one end of the leaf spring 3 in the width direction, and the rigid body 8 is engaged with the elastic body 5 so that the contact pressure of each protruding electrode can be uniformly maintained.

That is, by the action of the offset bar 21, the pressing force when the protruding electrode 13 touches down on the electrode surface of the DUT 54 can be made substantially constant, so that the DUT 54 of the protruding electrode 13 can be pressed. The amount of change or movement (see FIGS. 7C and 8C) on the electrode surface can be reduced, and damage and wear can be reduced.

In actual use, a plurality of probes according to the present invention are arranged side by side as in the conventional case, and each probe main body 2
The other end of the probe is rotatably supported and the protruding electrode 1 of each probe
3 are rotated in the same manner, and the electrode 5 of one DUT 54 is
Although pressed against the surface of No. 5, the probes can be manufactured to have substantially the same characteristics without variation even if they are installed in parallel, so that it is possible to uniformly and easily perform the measurement of the device under test having many electrode terminals. Become.

By the way, as a result of the probe of the present invention having the above-mentioned configuration, the following various measures can be easily taken.

First, the reliability of the contact can be easily obtained by arranging a plurality (two in the illustrated example) of the protruding electrodes 13 as the first protruding electrodes in parallel in the length direction of the conductor pattern 12, as shown in FIG. Can be secured.

That is, since the bump electrodes 13 are relatively small in shape and size, a plurality of bump electrodes 13 are provided to increase the contact area of the DUT with respect to the electrode terminals and reduce the contact resistance value.

Moreover, since the measurement environment is not a specially controlled environment such as a clean room, small dust and dirt are often attached to the electrode terminals of the device under test.
When it happens to be sandwiched between the protruding electrode 13 and the electrode terminal of the device under test, a situation may occur in which electrical contact cannot be obtained, so that such a situation can be prevented.

Next, as shown in FIG. 5, for example, a plurality of (three in the illustrated example) first protrusion electrodes 62 provided on the probe-side conductor pattern 61 are arranged in the width direction (direction diagonally intersecting in the illustrated example). If provided, it is possible to prevent the occurrence of contact failure due to manufacturing error or the like.

That is, since the width and pitch interval of the probe-side conductor pattern 61 are set according to the width and pitch interval of the electrode terminal 63 of the device under test, it is possible that the pitch intervals of both are exactly the same. Although ideal, the mechanical center lines of both patterns are displaced due to manufacturing errors, temperature changes, and the like.

As shown in the figure, this relative deviation is different for each electrode and is different. When the first protruding electrode 62 is one, the first protruding electrode 62 is the electrode terminal 63 of the device under test. In a place where there is a large deviation that exceeds the range of width, contact failure occurs. It is possible to prevent contact failure due to such relative displacement.

Further, the first protruding electrode has a thickness of 100 μm to 20 μm.
Although several tens to several hundreds are provided at a narrow interval of 0 μm, in the present invention, a means for confirming whether or not each first protruding electrode is actually in contact with the electrode terminal of the DUT before the measurement test. Can be configured.

That is, as shown in FIG. 6, the conductor pattern 12 shown in FIG. 1 is divided into two parts 71a and 71b which are insulated from each other.
The conductor pattern 71a is provided with a first protruding electrode 72a, and the conductor pattern 71b is provided with a first protruding electrode 72b.
The continuity test is performed with 1b.

Specifically, it can be constructed as shown in FIGS. 6 (a), 6 (b) and 6 (c), for example. 6 (a) (b)
Is a two-layer structure in which the conductor pattern 71a is formed on the lower surface of the insulator 73 and the conductor pattern 71b is formed on the upper surface,
A through hole is provided in the middle of the conductor pattern 71a, and the first protruding electrode 72b of the conductor pattern 71b is projected from the through hole to the same level as the first protruding electrode 72a of the conductor pattern 71a. In addition, in FIG.
3 is omitted, and two conductor patterns are shown in an overlapping manner.

Further, FIG. 6 (c) shows 2 of 71a and 71b.
Two conductor patterns are arranged on the same plane in a so-called zigzag pattern, and the first protrusion electrodes (72a, 72a) are provided at the tips of the conductor patterns.
b) is formed.

[0044]

As described above, according to the probe of the present invention, a plurality of first protruding electrodes at the tip of the stylus corresponding to the stylus made of a large number of metal wires arranged in a row in the past are tested. When a constant pressing force is formed in the pressure applying mechanism by the offset mechanism before contacting the body, and a plurality of first protruding electrodes are brought into contact with the DUT, the constant pressing force generated by the pressing mechanism causes the elastic body to move. All of the first protruding electrodes are brought into contact with the corresponding terminals of the device under test with a stable contact pressure.

Therefore, the contact reliability can be ensured without causing variations as in the prior art, and the change in the pressure applied to the test object at the time of pressurization can be reduced by the offset mechanism, so that the electrode surface of the test object can be reduced. It is possible to significantly reduce the damage given to the electrodes and the damage to the bump electrodes as well.

Further, the arrangement interval of the protruding electrodes can be set at an arbitrary interval and with high accuracy by the well-known printing technique, so that a constant and stable arrangement interval can be easily secured, and the arrangement interval of the narrow arrangement interval is flexible. There is an effect that can correspond to.

Further, unlike the prior art, it can be manufactured simply and uniformly without the need for assembling under a microscope, and the handling is very simple without using extra nerves, so that the cost can be reduced. There is an effect that is possible.

It should be noted that a plurality of first conductors are formed in one conductor pattern.
By arranging the protruding electrodes in parallel, it is possible to improve the reliability of contact, prevent the occurrence of contact failure due to manufacturing errors, etc. In addition, the conductor patterns corresponding to one electrode terminal of the DUT are insulated from each other. It is also possible to determine whether or not the two first projecting electrodes are in contact with the electrode terminals of the device under test, by configuring the two other conductor patterns and providing the first projecting electrodes on each.

[Brief description of drawings]

FIG. 1 is a perspective view of a probe according to an embodiment of the present invention.

FIG. 2 is a development view of a flexible printed circuit board attached to a probe body.

FIG. 3 is a side view showing the relationship (before measurement) between the probe of the present invention and the device under test.

FIG. 4 is a side view of the relationship (during measurement) between the probe of the present invention and the device under test.

FIG. 5 is a schematic plan view showing an example in which a plurality of first protruding electrodes are arranged in parallel in the width direction of a conductor pattern.

FIG. 6 is a configuration example in the case of confirming whether the first protruding electrode and the electrode terminal of the device under test are in contact, (a) shows 2
Side view of layer structure, (b) is a schematic plan view of (a), (c)
FIG. 3 is a schematic plan view of a staggered structure.

FIG. 7 shows a conventional probe (hook type), (a)
Is a perspective view, (b) is a side view of the DUT during measurement, (c)
[Fig. 4] is a conceptual view of a state when a stylus comes into contact with an electrode.

FIG. 8 shows a conventional probe (bar needle type), (a)
Is a perspective view, (b) is a side view of the DUT during measurement, (c)
[Fig. 4] is a conceptual view of a state when a stylus comes into contact with an electrode.

[Explanation of symbols]

 1 Flexible Printed Circuit Board 2 Probe Body 3 Leaf Spring 4 Adjusting Screw 5 Elastic Body 6 Clamp 7 Flat Cable 8 Rigid Body 11 Flexible Film 12 Conductor Pattern 13 Projection Electrode 14 Projection Electrode 15 Tip Part 21 Offset Bar 54 Test Object 55 Electrode 61 Probe Side conductor pattern 62 First protrusion electrode 63 Device under test electrode terminal 71a Conductor pattern 71b Conductor pattern 72a First protrusion electrode 72b First protrusion electrode 73 Insulator

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[Procedure amendment]

[Submission date] September 10, 1993

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

[Figure 4]

[Figure 5]

[Figure 6]

[Figure 8]

[Figure 7]

Claims (6)

[Claims] 1. A stylus tip having a plurality of first projecting electrodes formed on one side so as to be able to contact terminals of a device under test in a one-to-one correspondence, and an elastic body attached to the other side for stabilizing the contact. A plate-shaped circuit portion having a conductor pattern which is provided at one end and is connected to the plurality of first protrusion electrodes in a one-to-one correspondence; and which engages with the elastic body when the first protrusion electrode contacts a device under test. A pressing mechanism for applying a constant pressure to the first protruding electrode; and an offset mechanism for causing the pressing mechanism to form the constant pressing force before the first protruding electrode contacts the body under test. A probe characterized by being provided. 2. A stylus tip having a plurality of first projecting electrodes formed on one side so that the terminals of the device under test can be brought into one-to-one correspondence with each other and an elastic body for stabilizing the contact is attached to the other side. A plate-shaped circuit portion having a conductor pattern which is provided at one end and is connected to the plurality of first protrusion electrodes in a one-to-one correspondence; and which engages with the elastic body when the first protrusion electrode contacts a device under test. A pressure mechanism for applying a constant pressure to the first protruding electrode; and an offset mechanism for causing the pressure mechanism to generate the constant pressure before the first protruding electrode contacts the object to be tested. And a mechanism for connecting the other end of the conductor pattern to the cable from the measuring device without inverting the circuit sequence of the device under test. 3. The probe according to claim 1 or 2, wherein the plurality of first protruding electrodes are arranged in parallel in the lengthwise direction of the conductor pattern, respectively. And the probe. 4. The probe according to claim 1 or 2, wherein the plurality of first protruding electrodes are arranged side by side in the width direction of the conductor pattern, respectively. Probe to do. 5. The probe according to claim 1, wherein the plurality of first projecting electrodes are formed of two systems of projecting electrodes respectively formed at one ends of two conductor patterns insulated from each other. A probe characterized by: 6. The probe according to claim 1 or 2, wherein the plate-shaped circuit portion has a plurality of second projecting electrodes at the other end of the conductor pattern connected to the plurality of first projecting electrodes. A probe characterized by: