TW201600862A - Buckling probe for probe card - Google Patents

Abstract

A buckling probe for probe card comprises a needle tip, a needle tail staggered from the needle tip, and a needle body connected between the needle tip and the needle tail. The needle body is curved on a plane constituted by a first axis and a second axis and defines a width. The buckling probe for probe card is characterized in that the needle body has a gradually broadened section having a narrowest part having a minimal width and adjacent to the needle tip and a widest part having a maximal width and adjacent to the needle tail, and the gradually broadened section being gradually widened from the narrowest part toward the widest part. The ratio between the width of the widest part and that of the narrowest part is greater than or equal to 1.5. As such, the needle body has smaller swing angle when it is actuated, therefore improving the problem of wearing and needle jam.

Description

Deflection probe for probe card

The present invention relates to probes for probe cards, and more particularly to a buckling probe for a probe card.

FIG. 1 is a cross-sectional view showing a conventional buckling probe 11 mounted on a probe holder 12 and a lower guide plate 13, 14 between the upper and lower guide plates 13 and 14. The probe base 12 can be further provided with a plurality of probes 11 arranged corresponding to the electrical contacts of the object to be tested, so that the probes 11 simultaneously touch the electrical contacts. Figure 1 shows only a small portion of the probe holder 12 and a probe 11 for illustration.

The buckling probe 11 has a needle 15 that is disposed through a guiding hole 132 of the upper guiding plate 13 and is disposed at a guiding hole 142 of the lower guiding plate 14 and is misaligned with the needle 15 (ie, The needle tail 16 is not on the same line, and a needle body 17 extending from the bottom end of the needle 15 to the tip end of the needle tail 16 in an arc shape. The tip of the needle 15 is electrically connected to a tester (not shown) through a circuit board (not shown) or a space converter and a circuit board (not shown). The contact end 18 is used to press against the electrical contact of the object to be tested.

In the probe structure integrally formed by mechanical punching, the needle body 17 is originally rounded like the needle 15 and the needle tail 16, but the needle body 17 is further crushed by press working to make it from the first The shape seen in the direction shown is not only curved but also smaller than the needle 15 and the needle tail 16; thereby, when the point end 18 is pressed against the electrical contact of the object to be tested, the needle body 17 can produce a greater degree of bending in the direction in which it was originally bent, such that the point end 18 can move up and down with the height of the electrical contact of the object to be tested. In this way, the probe card When most of the buckling probes 11 are tested at different electrical contacts, the probes 11 can not only be in contact with each electrical contact but also electrically conduct, and the contact force is too large to be avoided. The electrical contacts of the test object or the probe 11 itself are damaged or excessively worn.

However, when the needle body 17 is elastically bent, a relatively large yaw angle θ (about 15 degrees) is generated between the section near the needle tail 16 and the needle tail 16, and at this time, the needle body 17 The resilience F can decompose a lateral component force F1 toward the wall of the hole of the guiding hole 142, and a direction downward and in the same axial direction as the guiding hole 142 so that the electrical property of the point of contact 18 is away from the object to be tested. The joint contributes to the axial component F2 of the needle tail 16 returning to the initial position. Since the lateral component force F1 acts on the hole wall of the guiding hole 142, and the yaw angle θ is larger, the lateral component force F1 is larger, and the excessive lateral force component F1 will cause the needle tail 16 and the hole wall. The frictional force is increased to be more easily worn, and the frictional force may completely offset the axial component force F2 that helps the needle tail 16 to return, so that the card in which the needle tail 16 is stuck in the guiding hole 142 and cannot be returned to the original position occurs. The needle phenomenon is not possible for the next touch operation.

In view of the above-mentioned deficiencies, the main object of the present invention is to provide a buckling probe for a probe card, which has a small yaw angle when the needle body is subjected to a force, thereby improving the problem of wear and stylus.

In order to achieve the above object, a buckling probe for a probe card provided by the present invention has a needle, a needle tail that is misaligned with the needle, and a needle body connecting the needle and the needle tail. The first axial direction and the second axial direction are curved and can define a width thereof; the deflection probe for the probe card is characterized in that the needle body has a gradually widening section, The widened section has a width that is the smallest and adjacent to the narrowest portion of the needle, and a widest portion that is the largest and adjacent to the tail of the needle, the widened section being substantially wide from the narrowest portion toward the widest portion The ratio of the width of the widest portion to the width of the narrowest portion is greater than or equal to 1.5.

Thereby, when the needle tail is stressed, the needle body is elastically bent and deformed When the width of the needle body is smaller, the deformation amount is larger, and the portion close to the needle tail has a larger width and a smaller deformation amount, so that the yaw angle between the needle and the needle tail is smaller, and the needle body is back. The lateral component of the elastic force is also small, so the buckling probe of the present invention is less prone to wear, has a longer service life than the conventional one, and is less prone to pinching.

Preferably, in the widened section of the needle body, the ratio of the width of the widest portion to the width of the narrowest portion is greater than or equal to 2; thereby, the yaw angle generated when the needle body is subjected to force is smaller Therefore, it can improve the wear and the needle problem.

Preferably, the needle body has a top end section connecting the needle, and the narrowest portion of the widened section can be located at the top end section. Alternatively, the needle body can have a top end and a tapered section extending from the top end to a substantially narrow width to the narrowest portion of the tapered section. The width of the tapered section at the top end may be less than the width of the widest portion of the tapered section. More preferably, the tapered section extends substantially from the top end in a direction of rotation that extends substantially from the narrowest portion toward the other direction of rotation.

Preferably, the needle body has a bottom end connected to the needle tail, and the widest portion of the widened section can be located at the bottom end. Alternatively, the needle body can have an equal width section that extends from the widest portion of the tapered section to the bottom end. Preferably, the width of the equal width section may be greater than or equal to the width of the widest portion of the tapered section.

Preferably, the needle body defines a thickness in a plane formed by the second axial direction and a third axial direction, and the needle body maintains an equal thickness.

Preferably, the tapered portion of the needle body has a minimum radius of curvature at the narrowest portion and a maximum radius of curvature at the widest portion.

Detailed construction, features, assembly or use of the buckling probe for a probe card provided by the present invention will be described in the detailed description of the subsequent embodiments. However, it should be understood by those of ordinary skill in the art that the present invention is not limited by the scope of the invention.

[Prior technology]

11‧‧‧Frustration probe

12‧‧‧ probe holder

13‧‧‧Upper guide

132‧‧‧ Guide hole

14‧‧‧Lower guide

142‧‧‧ Guide hole

15‧‧‧ needle

16‧‧‧needle tail

17‧‧‧ needle body

18‧‧‧ Pointer

Θ‧‧‧ yaw angle

F‧‧‧Resilience

F1‧‧‧lateral component

F2‧‧‧ axial component

[Examples]

21, 22, 23, 24, 25‧‧ ‧ deflection probe

30‧‧‧ probe holder

31‧‧‧Upper guide

312‧‧‧ Guide hole

32‧‧‧ lower guide

322‧‧‧ Guide hole

40‧‧‧ needle

42‧‧‧Connecting end

50‧‧‧needle tail

52‧‧‧ Pointer

60‧‧‧ needle body

61‧‧‧Top section

62‧‧‧ bottom

63‧‧‧Incremental section

631‧‧‧ narrowest part

632‧‧‧The widest part

64‧‧‧narrow section

65‧‧‧Wide section

66‧‧‧Top

Width of the narrowest part of w1‧‧

W2‧‧‧ width of the widest part

T‧‧‧thickness

1 is a cross-sectional view showing a conventional buckling probe mounted on a probe holder and a lower guide; FIGS. 2 and 3 are respectively provided for a first preferred embodiment of the present invention. Schematic diagram of the buckling probe of the probe card on two different planes; FIG. 4 is a yaw angle for the simulated deformation of the buckling probe of the probe card provided by the first preferred embodiment of the present invention A graph of the relationship between the width of the widest portion of the needle body and the width of the narrowest portion; FIG. 5 is a view of a type of buckling probe for a probe card according to a second preferred embodiment of the present invention; A schematic view similar to that of FIG. 2; FIG. 6 is a schematic view of a buckling probe for a probe card according to a third preferred embodiment of the present invention; FIG. One of the buckling probes for a probe card provided by the fourth preferred embodiment of the invention is similar to the schematic view of FIG.

The Applicant first describes the same or similar elements or structural features thereof in the embodiments and the drawings which will be described below. Secondly, in conjunction with the drawings of the following embodiments, the technical features of the present invention are merely described for convenience, and thus are not (and are not necessarily) drawn according to actual scales.

Please refer to FIG. 2 and FIG. 3 first. FIG. 2 is a first embodiment of the present invention. The buckling probe 21 for a probe card is provided in a first axial direction (X-axis) and a first embodiment. A schematic view of a plane (XY plane) formed by a second axial direction (Y-axis), and FIG. 3 is a view of the buckling probe 21 in the second axial direction (Y-axis) and a third axial direction (Z-axis) Schematic diagram of the plane (YZ plane) formed. The buckling probe 21 is mounted on a probe holder 30, a lower guide 31, 32. The probe holder 30 is actually provided with a plurality of probes 21, and FIGS. 2 and 3 show only a small portion of the probe holder 30 and a probe 21 for illustration.

The buckling probe 21 can be fabricated by using micro-electromechanical yellow lithography and electroplating technology, and has a needle 40 and a needle tail 50 offset from the needle 40 (that is, the needle 40 and the needle tail 50 are not located on the XY plane). On the same line), and a needle body 60 connecting the needle 40 and the needle tail 50. The needle 40 is configured to be inserted into a guiding hole 312 of the upper guiding plate 31, and a connecting end 42 of the top of the needle 40 is electrically connected to a circuit fixed on the upper guiding plate 31. Board or space converter (not shown). The needle tail 50 is configured to pass through a guiding hole 322 of the lower guiding plate 32, and the needle tail 50 has a point end 52 for electrically contacting an object to be tested (not shown). point. The present invention is characterized in that the shape of the needle body 60 is described in detail below.

The needle body 60 has a top end portion 61 connecting the needle head 40 and a bottom end 62 connecting the needle tail 50. The top end portion 61 can extend from the top end 66 of the needle body 60 and maintain the same width or different. The section of width. The top end 66 is configured to block a positioning film (not shown) disposed between the upper guide plate 31 and the needle body 60, or to block the upper guide plate 31. The needle body 60 is curved in a plane (XY plane) formed by the first axial direction (X-axis) and the second axial direction (Y-axis) and can define a width thereof, for example, as shown in FIG. Width w1, w2. The needle body 60 can define its thickness in the plane (Y-Z plane) formed by the second axial direction (Y-axis) and the third axial direction (Z-axis), for example, the thickness t shown in FIG. In the present embodiment, the needle body 60 is maintained at an equal thickness, that is, the needle body 60 has an equal thickness t from the top end 66 to the bottom end 62. In addition, the needle body 60 and the needle tail 50 and the needle 40 The thickness of the needle body 60 and the needle tail 50 and the needle 40 may not be equal; and the width of the needle body 60 is substantially gradually increased from the tip end section 61 to the bottom end 62.

In other words, the needle body 60 has a tapered section 63 having a smallest width and located at the narrowest portion 631 of the tip section 61, and a widest width and the widest at the bottom end 62. Part 632, the widened section The 63 series gradually increases in width from the narrowest portion 631 toward the widest portion 632. Therefore, when the point end 52 of the needle tail 50 is pressed against the electrical contact of the object to be tested to elastically deform the needle body 60, the portion of the needle body 60 whose deformation amount is large is located at the center thereof. Between the tip sections 61, the portion between the center of the needle body 60 and the bottom end 62 has a large width and a small amount of deformation, so that the yaw angle θ between the needle body 60 and the needle tail 50 is as in the prior art. The definition of FIG. 1 and the smaller one, in other words, the resilience provided by the deformation of the needle body 60 due to the deformation will have a smaller lateral force acting on the wall of the guide hole 322 of the lower guide 32. It can improve the problem of easy wear and thimble of the conventional buckling probe.

Since the buckling probe 21 can be fabricated using MEMS yellow lithography and electroplating techniques, the needle 40, the needle tail 50, and the cross section of the needle body 60 (XZ plane) in the second axial direction (Y-axis) The shape is non-circular, such as rectangular or square.

In order to verify whether the buckling probe 21 provided by the present invention can actually achieve the purpose of improving the conventional frustration probe for easy wear and stylus, the inventors of the present invention use the finite element analysis software ANSYS to simulate the widest part width and the most The ratio of the width of the narrow portion w2/w1 is a deformation condition when the buckling probe is subjected to a force of 1 to 3, and the simulated yaw angle θ and the w2/w1 are closed to the fourth figure. It can be known from the simulated results that the portion of the buckling probe that is mainly bent and deformed when the force is applied is in the upper half of the widened section 63, and the buckling probe having a larger w2/w1 has a bending deformation amount. The closest position is to the narrowest portion 631. As can be seen from Fig. 4, the yaw angle θ is w2/w1 as compared with the case where w2/w1 is 1 (i.e., the width of the conventional buckling probe is uniform and the yaw angle θ is about 15 degrees). In the case of 1.5, there has been a significant decrease, and in the case where w2/w1 is 2, the reduction is as much as 5 degrees. Secondly, the yaw angle θ reaches the maximum amplitude when w2/w1 is 2.5, and the yaw angle θ when w2/w1 is 3 is not significantly changed from the yaw angle θ where w2/w1 is 2.5. As the yaw angle θ is smaller, the repulsive force of the needle body 60 is decomposed to the smaller lateral force of the hole wall toward the guiding hole 322, and the probe is less likely to be worn and the needle pin is less likely to occur. Phenomenon, the design of the buckling probe of the present invention is as long as the widest portion 632 and the narrowest portion 631 of the widened section 63 The width ratio w2/w1 is greater than or equal to 1.5, which can obviously achieve the effect of non-wearing and stylus, and the design is better if w2/w1 is greater than or equal to 1.7 or 2 and w2/w1 is greater than or equal to 2.5.

It is to be noted that, in the embodiment of the present invention, the gradual increase of the width of the widened section 63 varies linearly, but is not limited thereto, for example, may be exponential or phased. As long as the needle body gradually increases in width or regularity toward the end of the needle, it is within the scope of "substantially increasing width" as described in the present invention. Moreover, the curved aspect of the needle body 60 can be, but is not limited to, non-maintaining a fixed radius of curvature. In an embodiment of the invention, the widened section 63 has a minimum radius of curvature at the narrowest portion 631 and is The widest portion 632 has a maximum radius of curvature, which is a preferred design.

In the foregoing embodiment, the needle body 60 is the widened section 63 as a whole. However, the buckling probe provided by the present invention is not limited thereto, as long as the needle body 60 has a widened section 63. The narrowest portion 631 and the widest portion 632 of the widened section 63 may be adjacent to the needle 40 and the needle tail 50, respectively, for example, as provided in the following three embodiments.

Referring to FIG. 5, in the buckling probe 23 provided by a second preferred embodiment of the present invention, the needle body 60 has a tapered section 63 as described above, and has a tapered section 64. The tapered section 64 extends substantially from the top end 66 of the needle body 60 to a narrowest portion 631 of the tapered section 63. The width of the tapered section 64 at the top end 66 can be, but is not limited to, ) is smaller than the width w2 of the widest portion 632 of the widened section 63. Moreover, the tapered section 64 extends substantially from the top end 66 in a rotational direction (counterclockwise in FIG. 5), the widened section 63 being substantially rotated from the narrowest portion 631 toward the other The direction (clockwise in Figure 5) extends. Thereby, the buckling probe 23 allows the stress to be more dispersed than the aforementioned probes 21, 22 which do not have the tapered portion 64, so as to avoid the probe being easily damaged due to stress concentration. The portion of the needle 40 that is engaged with the tip end 66 is provided with a lead angle, and the portion can also be used to block a positioning film (not shown) disposed between the upper guide plate 31 and the needle body 60, or The upper guide plate 31 is blocked.

As shown in Figures 6 and 7, the buckling probes 24, 25 of the third and fourth preferred embodiments of the present invention, the needle body 60 can have an equal width section 65, the width Section 65 extends from the widest portion 632 of the widened section 63 to the bottom end 62 substantially constant in width. As shown in FIG. 6, the width of the equal width section 65 may be equal to the width w2 of the widest portion 632 of the tapered section 63; or, as shown in FIG. 7, the width of the equal width section 65 may be The width w2 of the widest portion 632 of the widened portion 63 is greater than the width w2 of the widened portion 632, so that the equal width portion 65 can form a stop having a size larger than the diameter of the guide hole of the lower guide 32, so that the probe 25 can be The stopper is supported on the top surface of the lower guide plate 32 and can be stably held in the upper and lower guide plates without falling off. Further, the buckling probe provided by the present invention, in addition to the structural feature that the width of the gradually widening section is gradually increased, can further provide an additional connection with the widened section at the bottom end of the needle body. Block to support the probe on the lower guide.

When the buckling probe provided by the present invention is applied to a probe card, the buckling probe is less wearable due to less friction between the probe and the probe base, so the service life of the buckling probe of the present invention is longer. long. In addition, the chipping probability of the buckling probe is low, and the time and labor cost required for the card removing and repairing and the needle changing caused by the card pin can be avoided, so the present invention can improve the detection of the probe card when the probe object is to be tested. Test efficiency and reduce maintenance costs.

Finally, it is to be noted that the constituent elements disclosed in the foregoing embodiments are merely illustrative and are not intended to limit the scope of the present invention, and alternative or variations of other equivalent elements should also be the scope of the patent application of the present application. Covered.

21‧‧‧Frustration probe

30‧‧‧ probe holder

31‧‧‧Upper guide

312‧‧‧ Guide hole

32‧‧‧ lower guide

322‧‧‧ Guide hole

40‧‧‧ needle

42‧‧‧Connecting end

50‧‧‧needle tail

52‧‧‧ Pointer

60‧‧‧ needle body

61‧‧‧Top section

62‧‧‧ bottom

63‧‧‧Incremental section

631‧‧‧ narrowest part

632‧‧‧The widest part

66‧‧‧Top

Width of the narrowest part of w1‧‧

W2‧‧‧ width of the widest part

Claims (12)

A buckling probe for a probe card, having a needle, a needle tail that is offset from the needle, and a needle body connecting the needle and the needle tail, the needle body being in a first axial direction and a second The axially formed plane is curved and can define its width; the buckling probe for the probe card is characterized in that the needle body has a widened section, and the widened section has a width a minimum and adjacent to the narrowest portion of the needle, and a widest portion having the largest width and adjacent to the tail of the needle, the widened portion gradually increasing in width from the narrowest portion toward the widest portion, the widest portion The ratio of the width to the width of the narrowest portion is greater than or equal to 1.5. The buckling probe for a probe card according to claim 1, wherein in the widened section of the needle body, a ratio of a width of the widest portion to a width of the narrowest portion is greater than or equal to 2. The buckling probe for a probe card according to claim 1, wherein the needle body has a top end portion connecting the needle, and the narrowest portion of the widened portion is located at the top end portion . The buckling probe for a probe card according to claim 1, wherein the needle body has a bottom end connected to the needle tail, and the widest portion of the widened section is located at the bottom end. The buckling probe for a probe card according to claim 1, wherein the needle body has a top end connecting the needle, and a tapered section, wherein the tapered section is substantially from the top end The upper width gradually decreases to the narrowest portion of the tapered section. A buckling probe for a probe card according to claim 5, wherein the width of the tapered section at the top end is less than the width of the widest portion of the tapered section. The buckling probe for a probe card according to claim 5, wherein the tapered section extends substantially from the top end in a rotational direction, the widened section being substantially from the narrowest portion The upper direction extends in the other direction of rotation. The buckling probe for a probe card according to the first aspect of the invention, wherein the needle body has a bottom end connecting the needle tail, and an equal width section, wherein the width section is from the The widest portion of the wide section extends to the bottom end. A buckling probe for a probe card according to claim 8 wherein the width of the equal width section is greater than or equal to the width of the widest portion of the tapered section. The buckling probe for a probe card according to claim 1, wherein the needle body has a bottom end connected to the needle tail, and the bottom end has a stopper connected to the widened section. The buckling probe for a probe card according to the first aspect of the invention, wherein the needle body defines a thickness thereof on a plane formed by the second axial direction and a third axial direction, and The needle body maintains an equal thickness. A buckling probe for a probe card according to claim 1, wherein the widened section of the needle body has a minimum radius of curvature at the narrowest portion and a maximum radius of curvature at the widest portion.