Probe with low balance contact force

Abstract

Disclosed is a probe with low balance contact force comprising an elastic structure and a conductive body. The elastic structure has a first surface and a second surface, the first surface and the second surface being located on opposite sides of the elastic structure. The conductive body includes a first conductive body and a second conductive body. The first surface of the elastic structure corresponds to the first conductive body, the second surface of the elastic structure corresponds to the second conductive body, the first conductive body and the second conductive body are tightly coupled and covered by the elastic structure.

Description

Technical Field

[0001] This invention relates to a probe structure, and more particularly to a probe with low needle pressure. Prior Technology

[0002] The manufacturing process of integrated circuit chips requires electrical testing. Integrated circuit chips have pads or bumps formed on their electrode portions. Test probes measure the chip's electrical characteristics by making electrical connections to these electrodes. When the probe contacts the electrode, the tip of the probe applies a balance contact force (BCF) to establish an electrical connection.

[0003] If the pressure applied by the probe to the electrode is too high, it will leave deep or long scratches on the electrode and affect the strength of the wafer bonding in subsequent processes. Therefore, the pressure applied by the probe to the electrode must be well controlled. In the prior art, the probe body can be formed by at least two parallel pillars with at least one opening between the pillars. The parallel pillars and the opening form an elastic structure to reduce the pressure applied by the probe to the electrode.

[0004] The two parallel pillars formed on the probe are prone to breakage. In existing technology, the channel can be filled with polymeric material as a support to increase strength and solve the problem of parallel pillar breakage. However, this also increases the needle pressure at the probe contact electrode, which is not only detrimental to testing but also fails to solve the problem of increased impedance.

[0005] Furthermore, in high-current or high-frequency testing, besides controlling probe pressure, it is also desirable to reduce the impedance of the probe itself. For probes with the same cross-sectional area and material, existing technologies can reduce probe pressure by using channels, but this also increases impedance, which is detrimental to high-current or high-frequency testing requirements and also carries the risk of probe breakage. Existing solutions can increase the probe's cross-sectional area, for example, by increasing the probe's thickness; however, as the probe's cross-sectional area increases, the probe pressure also increases. Therefore, there is a need for a probe that can reduce probe pressure, reduce impedance, and is less prone to breakage, in order to solve the above-mentioned technical problems and provide more efficient testing for high-frequency and micro-motors. Summary of the Invention

[0006] The purpose of this invention is to provide a probe with low needle pressure, comprising an elastic structure and a conductor. The elastic structure has a first elastic surface and a second elastic surface, located on opposite sides of the elastic structure. The conductor includes a first conductor and a second conductor. The first elastic surface corresponds to the first conductor, and the second elastic surface corresponds to the second conductor. The first and second conductors are tightly bonded and cover at least a portion of the elastic structure. The hardness of the elastic structure is greater than the hardness of the conductor.

[0007] In one feasible embodiment, a plurality of ribs include a first rib and a second rib, and the connecting segment has a first area in a cross-section perpendicular to the central axis and exposed between the first rib and the second rib. The first rib has a first rib cross-section, the second rib has a second rib cross-section, the first rib cross-section has one side of the first rib cross-section, the second rib cross-section has one side of the second rib cross-section, and the side of the first rib cross-section and the side of the second rib cross-section are adjacent to each other and face each other. The conductor has a top surface and a bottom surface, which are two opposite sides of the conductor. The top surface has a side edge and another side edge that are parallel to each other. The side edge of the top surface is adjacent to one side edge of the first rib cross-section, and the other side edge is adjacent to one side edge of the second rib cross-section. The distance extending vertically from one side of the first rib section to the side of the top surface of the conductor, together with the distance from one side of the first rib section, is defined as the second area; the distance extending vertically from one side of the second rib section to the other side of the top surface of the conductor, together with the distance from one side of the second rib section, is defined as the third area.

[0008] In one feasible embodiment, the distance from one side of the top surface of the conductor to the other side of the top surface of the conductor is defined as the fourth area along with one side of the first rib cross-section.

[0009] In one feasible embodiment, the elastic structure further includes a top surface and a bottom surface, which are located at opposite ends of the central axis of the elastic structure. A first surface connects the top surface and the bottom surface, and a second surface connects the top surface and the bottom surface. When the top surface and the bottom surface of the elastic structure are flush with the top surface of the conductor, respectively, neither the top nor the bottom surface is covered by the conductor.

[0010] In one feasible embodiment, when the top surface of the elastic structure is joined to the top surface of the conductor, and the bottom surface of the elastic structure is joined to the bottom surface of the conductor, the top surface and the bottom surface of the elastic structure are covered by the conductor.

[0011] In one feasible embodiment, at least a portion of the conductor is disposed in the space.

[0012] In one feasible embodiment, the material of the elastic structure is a nickel alloy, a nickel-cobalt alloy, platinum, or a platinum alloy.

[0013] In one feasible embodiment, the materials of the first conductor and the second conductor are materials with high conductivity, such as gold, silver or copper.

[0014] In one feasible embodiment, the first conductor and the second conductive system are stacked on the elastic structure by electroplating.

[0015] In one feasible embodiment, the first conductor and the second conductor are tightly bound together by fusion.

[0016] In one feasible embodiment, the first conductor and the second conductor are made of the same material.

[0017] This invention provides a probe that reduces needle pressure and impedance while being less prone to breakage, thus solving the aforementioned technical problems. Compared to prior art, it provides more efficient testing for high-frequency and micro-motor applications. For a further understanding of the features and technical content of this invention, please refer to the following detailed description and figures. However, the figures provided are for reference and illustration only and are not intended to limit the scope of this invention. Simple Explanation of the Diagram

[0018] Figure 1 is a schematic diagram of the elastic structure of a first embodiment of the probe with low needle pressure of the present invention.

[0019] Figure 2 is a schematic diagram of a first embodiment of the probe with low needle pressure of the present invention.

[0020] Figure 3 is a front view of a first embodiment of the probe with low needle pressure of the present invention.

[0021] Figure 4 is a cross-sectional view along the IV-IV direction of Figure 2 of this invention.

[0022] Figure 5 is a schematic diagram of the elastic structure of a second embodiment of the probe with low needle pressure of the present invention.

[0023] Figure 6 is a schematic diagram of a second embodiment of the probe with low needle pressure of the present invention.

[0024] Figure 7 is a second schematic diagram of a second embodiment of the probe with low needle pressure of the present invention. Implementation

[0025] [First Embodiment]

[0026] Please refer to Figures 1, 2, 3, and 4. Figure 1 is a schematic diagram of the elastic structure 1 of the first embodiment of the probe 100 with low needle pressure of the present invention. Figure 2 is a schematic diagram of the first embodiment of the probe 100 with low needle pressure of the present invention. Figure 3 is a front view of the first embodiment of the probe 100 with low needle pressure of the present invention. Figure 4 is a cross-sectional view along direction IV-IV of Figure 2 of the present invention.

[0027] This invention discloses a probe 100 with low needle pressure, comprising an elastic structure 1 and a conductor 21. The elastic structure 1 is the probe, which can be a single probe, can be of various shapes (e.g., an S-shaped probe), or can be a MEMS pogo pin probe structure; this invention is not limited thereto.

[0028] Please refer to Figure 1. In the first embodiment of the present invention, the elastic structure 1 of the probe 100 with low needle pressure includes two ribs (a first rib 11 and a second rib 12) and two connecting segments (a first connecting segment 13 and a second connecting segment 14). The first connecting segment 13 connects one end of the first rib 11 and the second rib 12, and the second connecting segment 14 connects the other end of the first rib 11 and the second rib 12. A space 20 is formed between the first rib 11 and the second rib 12. It should be noted that the present invention does not limit the number of ribs, connecting segments, and spaces 20. There can be two, three, or more ribs, two, three, or more connecting segments, and the number of spaces 20 can be one or more in conjunction with the number of ribs.

[0029] The elastic structure 1 has a first elastic surface 15 and a second elastic surface 16. The first elastic surface 15 and the second elastic surface 16 are located on opposite sides of the elastic structure 1. The elastic structure 1 also includes a bottom elastic surface 17 and a top elastic surface 18, which are located at opposite ends of the central axis CL of the elastic structure 1. The bottom elastic surface 17 can be a surface of the first connecting segment 13 away from the second connecting segment 14, and the top elastic surface 18 can be a surface of the second connecting segment 14 away from the first connecting segment 13. The first elastic surface 15 connects the top elastic surface 18 and the bottom elastic surface 17, and the second elastic surface 16 connects the top elastic surface 18 and the bottom elastic surface 17. The elastic structure 1 also includes two side elastic surfaces 19. The two side elastic surfaces 19 connect the first elastic surface 15, the second elastic surface 16, the bottom elastic surface 17, and the top elastic surface 18, respectively.

[0030] Referring to Figure 2, the probe 100 with low needle pressure includes a conductor 21, which includes a first conductor 21a and a second conductor 21b. A first surface 15 of the elastic structure corresponds to the first conductor 21a, and a second surface 16 of the elastic structure corresponds to the second conductor 21b. In one embodiment, the first conductor 21a and the second conductor 21b can be formed on the elastic structure 1 by electroplating. In another embodiment, the first conductor 21a and the second conductor 21b can be two separate components, which are then tightly bonded together by high pressure and / or high temperature fusion and encapsulate the elastic structure 1.

[0031] At least a portion of the first conductor 21a and the second conductor 21b can be disposed in the space 20. Specifically, the space 20 is also covered with an electroplating layer due to the electroplating method, so that at least a portion of the first conductor 21a is disposed in a part of the space 20, or at least a portion of the first conductor 21a is disposed in the entire space 20; at least a portion of the second conductor 21b is disposed in a part of the space 20, or at least a portion of the second conductor 21b is disposed in the entire space 20. Specifically, by adopting a fusion method, at least a portion of the first conductor 21a is disposed in a part of the space 20, or at least a portion of the first conductor 21a is disposed in the entire space 20; at least a portion of the second conductor 21b is disposed in a part of the space 20, or at least a portion of the second conductor 21b is disposed in the entire space 20. That is to say, the space 20 may be filled by the first conductor 21a or the second conductor 21b, or it may not be filled by the first conductor 21a or the second conductor 21b.

[0032] Please refer to Figures 2 and 3. The conductor 21 includes a bottom surface B and a top surface T. When the first conductor 21a and the second conductor 21b tightly enclose the elastic structure 1, the bottom surface 17 of the elastic structure is flush with the bottom surface B of the conductor, and the top surface 18 of the elastic structure is flush with the top surface T of the conductor. Furthermore, the two elastic side surfaces 19 of the elastic structure 1 are covered by the conductor 21. When the top surface 18 of the elastic structure is flush with the top surface T of the conductor, and the bottom surface 17 of the elastic structure is flush with the bottom surface B of the conductor, neither the top surface 18 nor the bottom surface 17 of the elastic structure is covered by the conductor 21. That is, the bottom surface 17 of the elastic structure is coplanar with the bottom surface B of the conductor, and the top surface 18 of the elastic structure is coplanar with the top surface T of the conductor. However, this invention is not limited. Specifically, in one embodiment, when the top surface 18 of the elastic structure is joined to the top surface T of the conductor, and the bottom surface 17 of the elastic structure is joined to the bottom surface B of the conductor, the bottom surface 17 and the top surface 18 of the elastic structure can be covered by the conductor 21 without affecting the test. However, after several tests, the bottom surface 17 and the top surface 18 of the elastic structure will usually be exposed and not covered by the conductor 21.

[0033] Please refer to Figure 4, which is a cross-sectional view along the IV-IV direction of Figure 2. As shown in Figure 4, the conductor 21 can be partially formed on the elastic structure 1 by electroplating to form the third conductor 21c as shown in Figure 4. Next, the first conductor 21a and the second conductor 21b are tightly bonded together by high voltage and / or high temperature fusion, covering the elastic structure 1 on which the third conductor 21c is formed. Optionally, in this embodiment, at least a portion of the first conductor 21a and the second conductor 21b can also be disposed in the space 20; this is not a limitation of the present invention. Optionally, in this embodiment, the third conductor 21c, which is tightly bonded to and covers the elastic structure 1, can also form the entire conductor 21.

[0034] Optionally, the material of the elastic structure 1 may be a nickel alloy, a nickel-cobalt alloy, platinum, or a platinum alloy.

[0035] Optionally, the elastic structure 1 can be a conductor, and the conductivity of the first conductor 21a and the second conductor 21b can be greater than the conductivity of the elastic structure 1.

[0036] Optionally, the materials of the first conductor 21a and the second conductor 21b can be materials with high conductivity such as gold, silver or copper.

[0037] Optionally, the materials of the first conductor 21a and the second conductor 21b can be the same, so that the first conductor 21a and the second conductor 21b can have an optional and stable fusion, or the electroplating process is easier to achieve.

[0038] Optionally, the hardness of the elastic structure 1 is greater than that of the conductor 21. Specifically, using the elastic structure 1 with higher hardness, which is encased in the conductor 21, as a support not only avoids excessively increasing the needle pressure of the elastic structure 1 in contact with the test object, but also reduces the impedance.

[0039] The arrangement of the conductor 21 in this invention increases the current path of the probe 100 with low needle pressure, thereby reducing impedance. However, if the first conductor 21a and the second conductor 21b are made of materials with the same hardness as the elastic structure 1, or materials with a hardness greater than the elastic structure 1, the needle pressure will increase significantly, resulting in excessive contact pressure on the test object, which will affect subsequent testing and manufacturing processes of the wafer.

[0040] Optionally, after the first conductor 21a and the second conductor 21b are fused by high voltage and / or high temperature, the cross-sectional area (probe size) of the probe can be adjusted by laser, CNC machining or etching. The material around the probe 100 with low needle pressure after fusion exhibits irregular protrusions, and the appearance of the probe can also be smoothed out using the above-mentioned methods.

[0041] [Second Embodiment]

[0042] Please refer to Figures 5 to 7. Figure 5 is a schematic diagram of the elastic structure 2 of the second embodiment of the probe 200 with low needle pressure of the present invention. Figure 6 is a schematic diagram of the second embodiment of the probe 200 with low needle pressure of the present invention. Figure 7 is a second schematic diagram of the second embodiment of the probe 200 with low needle pressure of the present invention. The structure of the second embodiment of the present invention is similar to that of the first embodiment, and the structural similarities will not be described in detail. The difference between the second embodiment and the first embodiment is that the elastic structure 2 of the second embodiment has only one connecting segment connecting the first rib 11 and the second rib 12. Depending on the actual situation, the elastic structure 2 of the second embodiment may have only one connecting segment (first connecting segment 13) connecting one end of the first rib 11 and the second rib 12, while the other end of the first rib 11 and the second rib 12 is not connected, so that the first rib 11, the second rib 12 and the first connecting segment 13 form an elastic structure 2 similar to a U-shape or a concave shape.

[0043] Referring to Figure 5, in the second embodiment, the first rib 11 of the elastic structure 2 has a first rib section S1, and the second rib 12 of the elastic structure 2 has a second rib section S2. The first rib section S1 has one side edge 181 of the first rib section, and the second rib section S2 has one side edge 182 of the second rib section. The bottom surface 17 of the elastic structure may be a surface of the first connecting segment 13 away from the first rib section S1 and the second rib section S2.

[0044] Referring to Figure 6, the first connecting segment 13 has a first area A1 in a cross-section perpendicular to the central axis CL. One side 181 of the first rib cross-section is adjacent to and faces the other side 182 of the second rib cross-section. The top surface T of the conductor has a parallel side 211 and another side 212 of the top surface of the conductor. The side 211 of the top surface of the conductor is adjacent to one side 181 of the first rib cross-section, and the other side 212 of the top surface of the conductor is adjacent to one side 182 of the second rib cross-section. The area defined by the distance from one side 181 of the first rib cross-section perpendicular to the side 211 of the top surface of the conductor and the area defined by one side 181 of the first rib cross-section is the second area A2. The area defined by the distance from one side 182 of the second rib cross-section perpendicular to the other side 212 of the top surface of the conductor and the area defined by one side 182 of the second rib cross-section is the third area A3. The sum of the second area A2 and the third area A3 is greater than or equal to the first area A1.

[0045] Optionally, please refer to Figure 7, which is a second schematic diagram of a second embodiment of the probe 200 with low needle pressure of the present invention. The distance from the side 211 of the top surface of the conductor to the other side 212 of the top surface of the conductor and the side 181 of the first rib section is defined as the fourth area A4. The fourth area A4 is greater than the first area A1.

[0046] Similarly, the conductor 21 includes a bottom surface B and a top surface T. When the first conductor 21a and the second conductor 21b tightly enclose the elastic structure 2, the first rib section S1 of the first rib 11 and the second rib section S2 of the second rib 12 are respectively flush with the top surface T of the conductor. That is, the first rib section S1 and the second rib section S2 are coplanar with the top surface T of the conductor and are not covered by the conductor 21. When the bottom surface 17 of the elastic structure is flush with the bottom surface B of the conductor at a section perpendicular to the central axis CL, that is, the bottom surface 17 of the elastic structure is coplanar with the bottom surface B of the conductor and is not covered by the conductor 21. Similarly, the two sides 19 of the elastic structure 2 are covered by the conductor 21. Similarly, in one embodiment, when the top surface 18 of the elastic structure is joined to the top surface T of the conductor, and the bottom surface 17 of the elastic structure is joined to the bottom surface B of the conductor, the bottom surface 17 and the top surface 18 of the elastic structure can be covered by the conductor 21, which does not affect the test. However, after several tests, the bottom surface 17 and the top surface 18 of the elastic structure will usually be exposed and not covered by the conductor 21.

[0047] [Beneficial Effects of the Examples]

[0048] One beneficial effect of this invention is that the low-pressure probe provided by this invention can increase the overall current path of the probe by covering a harder elastic structure with a less rigid conductive material, thereby reducing impedance and effectively reducing the risk of probe breakage when contacting the test object, making the testing process more efficient. Another beneficial effect of this invention is that by arranging a plurality of ribs adjacent to each other, with adjacent ribs forming a space, the pressure can be controlled, reducing scratching of the electrode portion on the test object and avoiding interference with subsequent wafer bonding processes.

[0049] The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention specification and drawings are included in the scope of the patent application of the present invention.

[0050] 1, 2: Elastic structure 11: First Rib 12: Second rib 13: First connecting segment 14: Second connecting segment 15: First surface of the elastic structure 16: Second surface of elastic structure 17: Elastic structure bottom surface 18: Top surface of elastic structure 19: Side of the elastic structure 20: Space 21: Conductor 21a: First conductor 21b: Second conductor 21c: Third conductor 100, 200: Probes with low needle pressure 181: One side of the first rib section 182: One side of the second rib section 211: Side of the top surface of the conductor 212: The other side of the top surface of the conductor A1: First area A2: Second area A3: Third area B: Bottom surface of the conductor CL: Central axis S1: First rib section S2: Second rib section T: Top surface of the conductor

Claims

1. A probe with low needle pressure, wherein, The probe with low needle pressure includes: an elastic structure having a first elastic surface and a second elastic surface, the first elastic surface and the second elastic surface being located on opposite sides of the elastic structure; the elastic structure including: a plurality of ribs; and at least one connecting segment connecting two adjacent ribs, wherein the two adjacent ribs and the at least one connecting segment together define at least one space; and a conductor including a first conductor and a second conductor; wherein the first elastic surface of the elastic structure corresponds to the first conductor, the second elastic surface of the elastic structure corresponds to the second conductor, the first conductor and the second conductor are tightly bonded and cover at least a portion of the elastic structure, wherein the hardness of the elastic structure is greater than the hardness of the conductor; wherein the conductor has a bottom surface, and the bottom surface of the elastic structure is flush with the bottom surface of the conductor.

2. A probe with low needle pressure as described in claim 1, wherein, The plurality of ribs includes a first rib and a second rib. The connecting segment has a first area in a cross-section perpendicular to a central axis of the elastic structure and exposed between the first rib and the second rib. The first rib has a first rib cross-section, and the second rib has a second rib cross-section. The first rib cross-section has one side of the first rib cross-section, and the second rib cross-section has one side of the second rib cross-section. The side of the first rib cross-section and the side of the second rib cross-section are adjacent to and face each other. The conductor has a top surface and a bottom surface, which are two opposite surfaces of the conductor. The top surface has parallel side edges and another side edge. One side edge of the top surface is adjacent to one side edge of the first rib cross-section, and the other side edge is adjacent to one side edge of the second rib cross-section. The distance extending vertically from one side of the first rib section to the side of the top surface of the conductor, and the distance from one side of the first rib section to the other side of the top surface of the conductor, are defined as the second area; the distance extending vertically from one side of the second rib section to the other side of the top surface of the conductor, and the distance from one side of the second rib section, are defined as the third area; the sum of the second area and the third area is greater than or equal to the first area.

3. A probe with low needle pressure as described in claim 2, wherein, The distance from one side of the top surface of the conductor to the other side of the top surface of the conductor and one side of the first rib cross-section is defined as the fourth area, wherein the fourth area is greater than the first area.

4. A probe with low needle pressure as described in claim 2, wherein, The elastic structure further includes an elastic top surface and an elastic bottom surface, which are located at opposite ends of the central axis of the elastic structure. A first surface of the elastic structure connects the elastic top surface and the elastic bottom surface, and a second surface of the elastic structure connects the elastic top surface and the elastic bottom surface. When the elastic top surface is flush with the top surface of the conductor and the elastic bottom surface is flush with the bottom surface of the conductor, the elastic top surface and the elastic bottom surface are not covered by the conductor.

5. A probe with low needle pressure as described in claim 2, wherein, The elastic structure further includes a top surface and a bottom surface, which are located at opposite ends of the central axis of the elastic structure. A first surface of the elastic structure connects the top surface and the bottom surface, and a second surface connects the top surface and the bottom surface. When the top surface of the elastic structure is engaged with the top surface of the conductor, and the bottom surface of the elastic structure is engaged with the bottom surface of the conductor, the top surface and the bottom surface of the elastic structure are covered by the conductor.

6. A probe with low needle pressure as described in claim 5, wherein, At least a portion of the conductor is disposed in the space.

7. A probe with low needle pressure as described in claim 1, wherein, The material of the elastic structure is a nickel alloy, a nickel-cobalt alloy, platinum, or a platinum alloy.

8. A probe with low needle pressure as described in claim 1, wherein, The materials of the first conductor and the second conductor are materials with high conductivity, such as gold, silver or copper.

9. A probe with low needle pressure as described in claim 1, wherein, The first conductor and the second conductive system are stacked on the elastic structure by electroplating.

10. A probe with low needle pressure as described in claim 1, wherein, The first conductor and the second conductor are tightly bonded together by fusion.

11. A probe with low needle pressure as described in claim 1, wherein, The first conductor is made of the same material as the second conductor.

12. A probe with low needle pressure, wherein, The probe with low needle pressure includes: an elastic structure having a first elastic surface and a second elastic surface, the first and second elastic surfaces being located on opposite sides of the elastic structure; the elastic structure including: a plurality of ribs; and at least one connecting segment connecting two adjacent ribs, wherein the two adjacent ribs and the at least one connecting segment together define at least one space; and a conductor including a first conductor and a second conductor; wherein the first elastic surface of the elastic structure corresponds to the first conductor, the second elastic surface of the elastic structure corresponds to the second conductor, the first conductor and the second conductor are tightly bonded and cover at least a portion of the elastic structure, wherein the hardness of the elastic structure is greater than the hardness of the conductor; wherein the plurality of ribs includes a first rib and a second rib, and the connecting segment has a first area in a cross-section perpendicular to a central axis of the elastic structure and exposed between the first and second ribs. The first rib has a first rib cross-section, and the second rib has a second rib cross-section. The first rib cross-section has one side of the first rib cross-section, and the second rib cross-section has one side of the second rib cross-section. The side of the first rib cross-section and the side of the second rib cross-section are adjacent to each other and face each other. The conductor has a top surface and a bottom surface, which are two opposite surfaces of the conductor. The top surface has a parallel side and another side. The side of the top surface is adjacent to one side of the first rib cross-section, and the other side is adjacent to one side of the second rib cross-section. The distance extending vertically from one side of the first rib cross-section to the side of the top surface of the conductor, plus the distance from one side of the first rib cross-section to the other side of the top surface of the conductor, plus the distance from one side of the second ...

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