IE87268B1 - Horizontality-adjustable probe card - Google Patents

Abstract

A horizontality-adjustable probe card includes an elastic plate and a probe head. The elastic plate has a central portion and a plurality of adjusting arms extending from the periphery of the central portion. The probe head includes at least one probe. The probe head is disposed on the central portion of the elastic plate. As a result, the user can adjust the horizontality of the probe card after the assembly of the probe card is accomplished, thereby preventing height differences between the bottom ends of individual probes. <Figure 2>

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to probe cards and more particularly, to a horizontality-adjustable probe card. 2. Description of the Related Art The conventional probe card primarily includes a probe head provided at the bottom thereof with a plurality of probes protruding out, a space transformer disposed on 10 the top of the probe head, and a main circuit board disposed on the top of the space transformer. Alternatively, the probe card may include no such space transformer and the main circuit board is disposed on the top of the probe head directly. In this way, the main circuit board is adapted to be electrically connected to a tester, and bottom ends of the probes are adapted to contact electric contacts of a device under test, so that test signal 15 can be transmitted between the device under test and the tester through the probes and the space transformer and/or main circuit board.

However, under the influence of assembly accuracy, the bottom ends of the probes of the completely assembled probe card may have a little height difference therebetween instead of being located on the same horizontal plane. Although such height 20 difference is tiny, it is sufficient to cause different contact magnitudes between the probes and the electric contacts of the device under test and thus bring adverse influence. For example, some probes may damage the electric contacts because of applying overmuch probing pressure, some probes may cause unsteady signal transmission because of not contacting the electric contacts firmly and positively, and so on.

SUMMARY OF THE INVENTION 28/10/2020 The present invention has been accomplished in view of the above-noted circumstances. It is an objective of the present invention to provide a horizontality adjustable probe card, the horizontality of which is adjustable by the user after the 5 assembly of the probe card is accomplished, thereby preventing bottom ends of probes from height difference therebetween.

To attain the above objective, the present invention provides a horizontality adjustable probe card which includes an elastic plate and a probe head. The elastic plate has a central portion and a plurality of adjusting arms extending from the periphery of the 10 central portion. The probe head includes at least one probe. The probe head is disposed on the central portion of the elastic plate.

As a result, after the assembly of the probe card is accomplished, the user can change the posture of the elastic plate by swinging the adjusting arms. For example, each of the adjusting arms may be connected with a linear displacement device, such that the 15 adjusting arms can be driven by the linear displacement device to swing. Although such adjusting way causes tiny change to the posture of the central portion of the elastic plate, it is sufficient to adjust the horizontality of the probe head disposed on the central portion. The probe head usually has a plurality of probes, and/or works in association with one or more probes of another probe device (e.g. edge sensor), to probe a same device under test.

In the condition that the bottom ends of the probes have height difference therebetween, the aforementioned way of adjusting the horizontality of the probe head can eliminate the height difference by calibrating the bottom ends of the probes on the same horizontal plane, so that the probes can attain great probing effect.

Further scope of applicability of the present invention will become apparent 25 from the detailed description given hereinafter. However, it should be understood that the 28/10/2020 detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the scope of the invention will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: FIG. 1 is an assembled perspective view of a horizontality-adjustable probe card according to a preferred embodiment of the present invention; FIG. 2 is an exploded perspective view of the horizontality-adjustable probe card according to the preferred embodiment of the present invention; FIG. 3 is a bottom view of the horizontality-adjustable probe card according to the preferred embodiment of the present invention; FIG. 4 is a partially enlarged view of FIG. 3; FIG. 5 is a left view of the horizontality-adjustable probe card according to the preferred embodiment of the present invention; FIG. 6 is a partially enlarged view of FIG. 5; FIG. 7 is an assembled perspective view of a probe device and the horizontality- adjustable probe card according to the preferred embodiment of the present invention; and FIG. 8 is an exploded perspective view of the probe device and the horizontality-adjustable probe card according to the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION 28/10/2020 First of all, it is to be mentioned that same or similar reference numerals used in the following embodiments and the appendix drawings designate same or similar elements or the structural features thereof throughout the specification for the purpose of 5 concise illustration of the present invention. It should be noticed that for the convenience of illustration, the components and the structure shown in the figures are not drawn according to the real scale and amount, and the features mentioned in each embodiment can be applied in the other embodiments if the application is possible in practice. Besides, when it is mentioned that an element is disposed on another element, it means that the 10 former element is directly disposed on the latter element, or the former element is indirectly disposed on the latter element through one or more other elements between aforesaid former and latter elements. When it is mentioned that an element is directly disposed on another element, it means that no other element is disposed between aforesaid former and latter elements.

Referring to FIGS. 1-3, a horizontality-adjustable probe card 10 according to a preferred embodiment of the present invention includes an elastic plate 20, a probe head 30, a space transformer 12, a structure strengthening member 14, and three connecting plates 16. All the aforementioned members are approximately configured as plates arranged along horizontal axes, i.e. X-axis and Y-axis. The probe card 10 is adapted to move along a vertical axis, i.e. Z-axis, to make its probes contact electric contacts of a device under test (not shown), which will be specified in the following.

The elastic plate 20 has a circular central portion 22, and three adjusting arms 24 extending from the periphery of the central portion 22. Each of the adjusting arms 24 includes an elongated extending portion 242 extending from the periphery of the central 25 portion 22, and an installation portion 244 located at the terminal end of the extending 28/10/2020 portion 242 and wider than the extending portion 242. In this embodiment, the elastic plate 20 is a circuit board provided with internal circuit (not shown), which is very thin in thickness, thereby capable of slight elastic bending deformation. The elastic plate 20 is provided on the bottom surface 25 thereof with electric contacts (not shown) located at the central portion 22. The elastic plate 20 is provided on the top surface 26 thereof with a plurality of electric connectors 28. Each of the three adjusting arms 24 is provided with at least one electric connector 28 disposed on the installation portion 244. Each of the electric connectors 28 is electrically connected with the electric contact of the bottom surface 25 of the elastic plate 20 through the internal circuit of the elastic plate 20.

The probe head 30 includes an upper plate 31, a lower plate 32, a circuit board fixed between the upper plate 31 and the lower plate 32, and sixteen probes 34 (unlimited in amount) manufactured by microelectromechanical system (also referred to as MEMS) and formed on the bottom surface 332 of the circuit board 33, as shown in FIGS. 4-6. Each of the probes 34 includes a cantilever section 341 extending along Y- axis, and a contact section 342 extending along Z-axis. Specifically speaking, the cantilever sections 341 of the eight probes 34 located in the left half of FIG. 4 extend in the positive direction of Y-axis, and the cantilever sections 341 of the other eight probes 34 located in the right half of FIG. 4 extend in the negative direction of Y-axis. The terminal ends of the cantilever sections 341 of the probes 34 in the left half and the terminal ends of the cantilever sections 341 of the probes 34 in the right half are arranged in a staggered manner and aligned along a straight line L. As shown in FIG. 5 and FIG. 6, the contact sections 342 of the probes 34 extend from the terminal ends of the cantilever sections 341 in the negative direction of Z-axis to protrude downwardly at the bottom of the probe head 30, so that the contact ends 344 located at the bottoms of the contact sections 342 are adapted to downwardly contact the electric contacts of the device under test. 28/10/2020 The probe head 30 is disposed on the bottom surface 25 of the elastic plate 20 through the space transformer 12 and disposed on the central portion 22 in a way that the probes 34 are electrically connected with the electric contacts of the bottom surface 25 of 5 the elastic plate 20. The aforesaid connecting way is well known in the art and relatively less relates to the features of the present invention, thereby not being detailedly described hereinafter. When the electric connectors 28 of the elastic plate 20 are electrically connected to a tester (not shown) through signal transmitting wires (not shown), test signal can be transmitted between the tester and the device under test that is in contact 10 with the contact ends 344 of the probes 34 through the probe head 30, the space transformer 12, the elastic plate 20 and the aforementioned signal transmitting wires.

The structure strengthening member 14 and the three connecting plates 16 are fixed on the top surface 26 of the elastic plate 20. The structure strengthening member 14 is disposed on the central portion 22 to strengthen the structural strength of the central 15 portion 22, thereby improving the stability of the probe head 30. The three connecting plates 16 are disposed on the installation portions 244 of the three adjusting arms 24 respectively for three linear displacement devices (not shown), such as slide rail and slider sets, pneumatic cylinders, hydraulic cylinders, etc., to be connected with the three connecting plates 16 respectively. In this way, each of the linear displacement devices 20 disposed on the top surface 26 of the elastic plate 20 can perform linear displacement along Z-axis to drive the associated adjusting arm 24 to swing upwardly and downwardly. Alternatively, the aforementioned linear displacement devices may be disposed on the adjusting arms 24 directly without connecting plates 16 therebetween, thereby directly driving the associated adjusting arms 24 to swing upwardly and downwardly.

As a result, after the assembly of the probe card 10 is accomplished, if the 28/10/2020 contact ends 344 of the probes 34 have a little height difference therebetween, for example, if the contact ends 344 of the probes 34 in this embodiment are not arranged in a straight line along X-axis as shown in FIG. 6, the horizontality of the probe head 30 is adjustable in a way that the abovementioned linear displacement devices on the three connecting plates 16 perform linear displacement along Z-axis to swing the adjusting arms 24 to change the posture of the elastic plate 20. Such way can eliminate the height difference by arranging the contact ends 344 of the probes 34 on the same horizontal plane to make the probes 34 attain great probing effect.

As shown in FIG. 3, the three adjusting arms 24 of the elastic plate 20 in this embodiment extend from the periphery of the central portion 22 radially with equal included angles Θ therebetween, which means the included angle Θ between every two adjacent adjusting arms 24 is about 120 degrees. One of the adjusting arms 24 extends in the positive direction of Y-axis. As shown in FIG. 4, the contact sections 342 of the probes 34 of the probe head 30 are arranged in a straight line L along X-axis. In other words, the contact sections 342 of the probes 34 are arranged in a straight line L perpendicular to the extending direction of one of the adjusting arms 24. Such arrangement doesn’t need many adjusting arms 24, but has great effect in adjusting the horizontality of the probes 34. However, the elastic plate 20 of the present invention is unlimited to have three adjusting arms 24, as long as the elastic plate 20 has a plurality of adjusting arms 24. The positional arrangement of the adjusting arms 24 is also unlimited. Besides, the probes 34 of the probe head 30 of the present invention are unlimited to be arranged in a straight line. ft is to be mentioned that the probe head 30 usually has a plurality of probes 34, but unlimited thereto. No matter the probe head 30 has one or a plurality of probes 34, the probe 34 of the probe head 30 may work in association with at least one probe of another probe device to probe the same device under test at the same time. For example, 28/10/2020 the aforementioned another probe device may be an edge sensor 40 as shown in FIG. 7 and FIG. 8. Specifically speaking, the probe card 10 is provided at the center thereof with a through hole 18 which penetrates through the structure strengthening member 14, the elastic plate 20, the space transformer 12 and the probe head 30. The contact ends 344 of 5 the probes 34 of the probe head 30 are located below and aimed at the through hole 18.

The structure strengthening member 14 has a notch 142 communicating with the through hole 18 for the probe device (e.g. edge sensor) 40 to be disposed in the notch 142 and a probe 42 of the probe device 40 to be inserted through the through hole 18. In this way, the probes 34 of the probe head 30 and the probes 42 of the probe device 40 can probe 10 the same device under test at the same time, and the above-described way of swinging the adjusting arms 24 of the elastic plate 20 is also adapted to eliminate height difference between the probes 34 and 42. Besides, as shown in FIG. 2 and FIG. 3, the probe card may include force sensors 19 (e.g. load cells) disposed on the adjusting arms 24 of the elastic plate 20 for measuring force acting on the probes 34 when they contact the device 15 under test. Furthermore, the probe card may include displacement sensors (not shown) disposed on the adjusting arms 24 to sense displacement along Z-axis for the calculation of the posture of the elastic plate 20. The force sensors 19 may be disposed on the top and bottom surfaces of the adjusting arms 24 of the elastic plate 20. Further speaking, the force sensors 19 may be disposed on the extending portions 242 or installation portions 20 244 of the adjusting arms 24. As shown in FIG. 2 and FIG. 3, the force sensors 19 may be disposed at the junctures of the extending portions 242 and installation portions 244 of the adjusting arms 24.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the scope 25 of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.

Claims (10)

WHAT IS CLAIMED IS: 28/10/2020

1. A horizontality-adjustable probe card comprising: an elastic plate having a central portion and a plurality of adjusting arms extending from a periphery of the central portion; and 5 a probe head comprising at least one probe, the probe head being disposed on the central portion of the elastic plate.

2. The horizontality-adjustable probe card as claimed in claim 1, wherein the adjusting arms of the elastic plate extend from the periphery of the central portion radially 10 with equal included angles therebetween.

3. The horizontality-adjustable probe card as claimed in claim 1, wherein the elastic plate has three of said adjusting arms. 15

4. The horizontality-adjustable probe card as claimed in claim 1, wherein the elastic plate has three of said adjusting arms extending from the periphery of the central portion radially with equal included angles therebetween; the probe head comprises a plurality of said probes; each of the probes has a contact section; the contact sections of the probes are arranged in a straight line perpendicular to an extending direction of one 20 of the adjusting arms.

5. The horizontality-adjustable probe card as claimed in claim 1, wherein the elastic plate has a top surface and a bottom surface opposite to the top surface; the probe head is disposed on the bottom surface of the elastic plate; the probe card further 25 comprises a structure strengthening member disposed on the top surface of the elastic plate and located at the central portion. 28/10/2020

6. The horizontality-adjustable probe card as claimed in claim 5, wherein the probe card has a through hole; a contact end of the probe of the probe head is located 5 below and aimed at the through hole; the structure strengthening member has a notch communicating with the through hole for a probe device to be disposed in the notch and a probe of the probe device to be inserted through the through hole.

7. The horizontality-adjustable probe card as claimed in claim 1, wherein the 10 horizontality-adjustable probe card further comprises a plurality of connecting plates; the connecting plates are disposed on the adjusting arms of the elastic plate respectively for being connected with linear displacement devices, respectively, such that each of the adjusting arms is driven by one of the linear displacement devices to swing. 15

8. The horizontality-adjustable probe card as claimed in claim 7, wherein the elastic plate has a top surface and a bottom surface opposite to the top surface; the probe head is disposed on the bottom surface of the elastic plate; the connecting plates are disposed on the top surface of the elastic plate for each of the linear displacement devices to be disposed on the top surface of the elastic plate.

9. The horizontality-adjustable probe card as claimed in claim 1, wherein the elastic plate is a circuit board and has a plurality of electric connectors electrically connected with internal circuit of the circuit board and located at the adjusting arms. 25

10. The horizontality-adjustable probe card as claimed in claim 1, further comprising a plurality of force sensors disposed on the adjusting arms of the elastic plate.