Probe and electrical connection device
Patent Information
- Application Number
- JP2022180871
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2022-11-11
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2042-11-11
AI Technical Summary
Existing electrical connection devices face instability in the contact between probes and lands, leading to inconsistent electrical testing results.
A probe design with a column-shaped base material and a contact film covering side surfaces except one, featuring a flat end surface and a tapered connection region, which stabilizes contact with lands.
The probe design ensures stable and durable contact with lands, preventing adjacent probe interference and maintaining consistent electrical conductivity.
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a probe and an electrical connection device used for testing electrical characteristics of an object under test. [Background technology]
[0002] An electrical connection device including a probe is used to test electrical characteristics of an object to be tested, such as a semiconductor integrated circuit, in a wafer state. In a test using a probe, one end of the probe is brought into contact with an electrode of the object to be tested, and the other end of the probe is brought into contact with a terminal (hereinafter referred to as a "land") arranged on a printed circuit board or the like. The land is electrically connected to a tester or other such testing device. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] JP 2015-118064 A Summary of the Invention [Problem to be solved by the invention]
[0004] In order to accurately test the electrical characteristics of an object to be tested, stable contact between the probe and the land is necessary. An object of the present invention is to provide a probe and an electrical connecting device that can make stable contact with the land. [Means for solving the problem]
[0005] A probe according to one aspect of the present invention includes a columnar base material having a first end and a second end, a polygonal cross section perpendicular to the axial direction, and a contact film covering the remaining side surfaces of the second end except for a side surface facing a first direction among a plurality of side surfaces connected to a tip surface of the second end, and the tip surface of the second end. The end surface of the contact film covering the tip surface of the second end is a plane perpendicular to the axial direction. Effect of the Invention
[0006] According to the present invention, it is possible to provide a probe and an electrical connecting device capable of stably contacting a land. [Brief description of the drawings]
[0007] [Figure 1] FIG. 2 is a schematic diagram showing a configuration of a probe according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view taken along the II-II direction in FIG. [Diagram 3] 4 is a schematic perspective view showing a configuration of a second end portion of the probe according to the embodiment of the present invention. FIG. [Figure 4] 5 is a schematic perspective view showing a configuration of a second end portion of the probe according to the embodiment of the present invention. FIG. [Diagram 5] 1 is a schematic diagram showing a configuration of an electrical connecting device according to an embodiment of the present invention. [Figure 6] 11 is a schematic diagram showing a contact state between a probe and a land in the first comparative example. FIG. [Figure 7] 5A and 5B are schematic diagrams showing a state in which a probe and a land are in contact with each other according to the embodiment of the present invention; [Figure 8] FIG. 13 is a schematic diagram showing a state in which non-tapered probes are arranged adjacent to each other. [Figure 9] FIG. 13 is a schematic diagram showing a state in which tapered probes are arranged adjacent to each other. [Figure 10] 13 is a schematic perspective view showing the configuration of a second end portion of a probe of a second comparative example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] Next, an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the thickness ratios of each part are different from the actual ones. Of course, the drawings also include parts with different dimensional relationships and ratios. The embodiments shown below are examples of devices and methods for embodying the technical ideas of this invention, and the embodiments of this invention do not specify the materials, shapes, structures, arrangements, and manufacturing methods of the components as described below.
[0009] A probe 1 according to an embodiment shown in Fig. 1 is used to inspect electrical characteristics of an object to be inspected. The probe 1 includes a base material 10 having a first end 11, which is one end that comes into contact with an object to be inspected (not shown) during inspection, and a second end 12, which is the other end, and a contact film 13 that covers a part of the second end 12 of the base material 10. The base material 10 has a columnar shape extending along an axial direction D3. During inspection of the object to be inspected, the second end 12 comes into contact with a land.
[0010] The base material 10 has a polygonal cross section (hereinafter, simply referred to as a "cross section") perpendicular to the axial direction D3. In the following, a case where the cross section of the base material 10 is rectangular as shown in FIG. 2 will be described as an example. The second end portion 12 has four side surfaces connected to the tip surface 121. That is, the second end portion 12 has a first side surface S1 facing the first direction D1, a second side surface S2 facing the opposite side to the first direction D1, a third side surface S3 facing the second direction D2 perpendicular to the first direction D1, and a fourth side surface S4 facing the opposite side to the second direction D2. Hereinafter, when each of the first side surface S1 to the fourth side surface S4 is not limited, it will be referred to as a side surface S.
[0011] The contact film 13 covers the remaining side surfaces of the second end 12, excluding the side surfaces facing the first direction D1, among the multiple side surfaces connected to the tip surface 121 of the second end 12, and the tip surface 121 of the second end 12. As shown in Figs. 2, 3 and 4, the contact film 13 covers the remaining side surfaces S of the region of the second end 12 connected to the tip surface 121 (hereinafter referred to as the "tip region 122"), excluding the first side surface S1 facing the first direction D1. That is, in the probe 1 having a rectangular cross section, the contact film 13 covers the second side surface S2, the third side surface S3 and the fourth side surface S4 of the tip region 122. Furthermore, as shown in Fig. 1, the contact film 13 covers the tip surface 121 of the second end 12. The end surface 131 of the contact film 13 covering the tip surface 121 of the second end 12 is a plane perpendicular to the axial direction D3.
[0012] As shown in Figures 3 and 4, it is preferable that the corners of the end face 131 of the contact film 13 are chamfered. In the contact film 13 shown in Figures 3 and 4, the connection portion between the outer side surface and the end face 131 when viewed from the first direction D1 is rounded.
[0013] The tip surface 121 of the second end 12 is a plane perpendicular to the axial direction D3. The tip region 122 covered by the contact film 13 is rectangular in side view from the first direction D1 and the second direction D2. Therefore, the end surface 131 of the contact film 13 covering the tip surface 121 of the second end 12 is a plane, and the part of the contact film 13 covering the side surface S of the second end 12 is perpendicular to the end surface 131.
[0014] For reasons that will be described later, it is preferable that the region of the second end 12 that is exposed to the outside of the contact film 13 and that connects to the tip region 122 (hereinafter referred to as the "connection region") has a tapered shape in which the cross section of the base material 10 gradually narrows toward the tip surface 121. In Figures 3 and 4, the extensions of the third side surface S3 and the fourth side surface S4 of the connection region 123, which is the outer side surface S when viewed from the first direction D1, intersect with the tip surface 121 at an obtuse angle. Hereinafter, the side surface S of the connection region 123 whose extensions intersect with the tip surface 121 at an obtuse angle is also referred to as the "tapered side surface."
[0015] To electrically connect the electrodes of the test object to the lands, a conductive material such as a metal material is used for the base material 10 and the contact film 13. For example, the contact film 13 may be formed on the surface of the base material 10 by plating.
[0016] It is preferable to select the materials of the base material 10 and the contact film 13 so that the conductivity of the base material 10 and the contact film 13 is equal or the conductivity of the contact film 13 is higher than that of the base material 10. By selecting the materials of the base material 10 and the contact film 13 in this way, the electrical resistance between the probe 1 and the land can be reduced. For example, nickel (Ni), nickel alloy, gold (Au), silver (Ag), copper (Cu), palladium (Pd), palladium alloy, rhodium (Rh), rhodium alloy, other precious metals, etc. are preferably used for the base material 10. Gold (Au), silver (Ag), copper (Cu), other precious metals, etc. are preferably used for the contact film 13.
[0017] The probe 1 is used in, for example, an electrical connecting device 100 shown in FIG. 5. In the electrical connecting device 100, the probe 1 is held by a probe head 20. Specifically, a plurality of probes 1 are inserted into guide holes of a first guide plate 21, a second guide plate 22, and a third guide plate 23 included in the probe head 20, and are held by the probe head 20. Hereinafter, the first guide plate 21, the second guide plate 22, and the third guide plate 23 will be referred to as guide plates unless otherwise specified. The probe head 20 has a configuration in which the first guide plate 21, the second guide plate 22, and the third guide plate 23 are arranged at a distance from each other in the surface normal direction (Z direction) of the main surfaces of the guide plates.
[0018] A first end 11 of the probe 1 comes into contact with an electrode pad (not shown) of the test object 2 when the test object 2 is tested. A contact film 13 covering a tip region 122 of a second end 12 of the probe 1 comes into contact with a land 31 of a substrate 30. The land 31 is electrically connected to a test device such as an IC tester (not shown).
[0019] As shown in FIG. 5, for guide holes through which the same probe 1 penetrates, the positions of the guide holes of the first guide plate 21 are shifted in the −X direction parallel to the main surface of the second guide plate 22 relative to the guide holes of the second guide plate 22. FIG. 5 is a side view seen from the Y direction perpendicular to both the X direction and the Z direction. Hereinafter, the shifted position of the guide holes is referred to as the “offset position”. The direction in which the guide holes are shifted is also referred to as the “offset direction”. In FIG. 5, the offset direction is the −X direction. Due to the offset position, the base material 10 of the probe 1 is curved inside the probe head 20. That is, in the hollow region 200 between the first guide plate 21 and the second guide plate 22, the base material 10 is in a curved state due to elastic deformation. The positions of the guide holes of the second guide plate 22 and the third guide plate 23 coincide with each other when viewed from the Z direction.
[0020] Due to the offset arrangement of the guide hole of the first guide plate 21 and the guide hole of the second guide plate 22, when the first end 11 of the probe 1 comes into contact with the test object 2, the probe 1 buckles in the hollow area 200. That is, in a contact state in which the probe 1 comes into contact with the test object 2, the probe 1 is further curved by flexural deformation from the curved shape in a non-contact state in which the probe 1 is not in contact with the test object 2. As the probe 1 further bends, it comes into contact with the test object 2 with a predetermined pressure. Therefore, due to the offset arrangement, the electrical characteristics of the test object 2 can be stably measured using the probe 1. When the probe 1 is in a non-contact state, it has the elasticity to return to the shape before contacting the test object 2.
[0021] The probe 1 is attached to the probe head 20 so that the first direction D1 is the same as the offset direction. In other words, the first side surface S1 of the second end portion 12 that is not covered by the contact film 13 is oriented in the same direction as the offset direction. Therefore, as described below, it is possible to prevent the probe 1 from contacting a land other than a predetermined target land (hereinafter referred to as a "target land").
[0022] The probe of the first comparative example in which all the side surfaces S of the second end 12 are covered with the contact film 13 will be considered below. As shown in FIG. 6, due to the offset arrangement, the second end 12 is likely to tilt obliquely with respect to the Z direction. In this case, in the probe of the first comparative example in which all the side surfaces S of the second end 12 are covered with the contact film 13, when the land interval of the substrate 30 is narrow, the contact film 13 covering the second end 12 and the land adjacent to the target land 31A in the offset direction (hereinafter also referred to as "adjacent land") approach each other. For this reason, there is a risk that the contact film 13 and the adjacent land 31B will come into contact. In particular, when the position of the second end 12 is shifted parallel to the X direction, contact between the contact film 13 and the adjacent land 31B is likely to occur.
[0023] In contrast, in the probe 1 in which the first side surface S1 is not covered with the contact film 13, a wide interval can be secured between the contact film 13 and the adjacent land 31B as shown in Fig. 7. Therefore, the probe 1 can suppress contact between the probe 1 and the adjacent land 31B.
[0024] In this way, the probe 1 is easily tilted in the offset direction with respect to the Z direction due to the influence of the offset arrangement. In addition, since a gap (clearance) is provided between the probe 1 and the guide hole in each of the X and Y directions, the probe 1 may also tilt in a direction perpendicular to the offset direction, that is, in the Y direction. As shown in FIG. 8, when the probe 1 tilts in the Y direction, it approaches the adjacent probe 1. For this reason, it is preferable to make the connection region 123 of the second end portion 12 tapered by making the third side surface S3 and the fourth side surface S4 facing the Y direction tapered side surfaces. By making the connection region 123 of the second end portion 12 tapered, it is possible to suppress contact between adjacent probes 1 as shown in FIG. 9. Furthermore, by making the connection region 123 tapered, the contact area of the end surface 131 can be made smaller than the cross-sectional area of the base material 10, so that the pressing force of the probe 1 pressing the land 31 can be increased and the contact stability between the probe 1 and the land 31 can be improved.
[0025] In the above, the case where the third side surface S3 and the fourth side surface S4 are tapered side surfaces has been described as an example. However, it is arbitrary which side surface S of the connection region 123 is made into a tapered side surface. For example, all side surfaces S of the connection region 123 may be made into tapered side surfaces. This makes it possible to suppress contact between the probes 1 even if the probes 1 are tilted in any direction. Alternatively, only one side surface S facing the direction in which the probe 1 is likely to tilt may be made into a tapered side surface. This makes it possible to shorten the manufacturing process of the probe 1. Regardless of whether any side surface S is made into a tapered side surface, by reducing the area of the tip surface 121 of the second end portion 12, it is possible to suppress contact between adjacent probes 1 even if the probes 1 are misaligned.
[0026] As described above, in the probe 1, the tip region 122 of the second end 12 is covered with the contact film 13, and the end surface 131 of the contact film 13 is flat. Therefore, the probe 1 can stabilize the contact between the second end 12 and the land, compared to the probe of the second comparative example shown in FIG. 10 in which the contact member 15 that contacts the land is embedded in the second end 12. That is, in the probe of the second comparative example, the contact with the land is point contact. On the other hand, in the probe 1 in which the tip region 122 of the second end 12 is covered with the contact film 13, the contact with the land is surface contact. Therefore, the contact between the probe 1 and the land is stable. As a result, good electrical conduction between the test object and the land can be achieved.
[0027] In addition, in the probe of the second comparative example shown in FIG. 10, repeated contact with the land causes the contact member 15 to deform, shortening the overall length of the probe. As a result, a gap is generated between the probe and the land, and poor contact between the probe and the land is likely to occur. In contrast, in the electrical connection device 100 including the probe 1 in which the tip region 122 of the second end 12 is covered with the contact film 13, deformation of the tip region 122 can be suppressed. Therefore, poor contact between the probe 1 and the land can be prevented. In addition, in the probe 1, since the second end 12 of the base material 10 is covered with the contact film 13, it is relatively easy to adjust the composition and film thickness of the film, so that the design freedom of the probe 1 can be increased. Furthermore, in the probe 1, all side surfaces S connected to the end surface 131 are perpendicular to the end surface 131. Therefore, for example, the plated contact film 13 is less likely to peel off from the base material 10 than a tapered shape in which the cross section of the base material becomes wider as the side surface S moves away from the end surface 131, and the durability of the probe 1 can be improved. In particular, the probe 1 requires the contact film 13 to be durable since the contact film 13 repeatedly comes into contact with the land, but since all side surfaces S are perpendicular to the end face 131, the contact film 13 is less likely to peel off, and the durability of the probe 1 can be increased.
[0028] As described above, in the probe 1 according to the embodiment of the present invention, the tip region 122 of the second end 12 is covered by the contact film 13 having a flat end surface 131. Therefore, the probe 1 can stably contact the second end 12 with the land. Furthermore, in the electrical connection device 100 including the probe 1, the contact film 13 is not arranged on the first side surface S1 of the tip region 122 parallel to the offset direction of the probe 1. Therefore, the electrical connection device 100 can prevent the probe 1 from contacting an adjacent land. Furthermore, the electrical connection device 100 including the probe 1 having the connection region 123 having a tapered shape can prevent adjacent probes 1 from contacting each other.
[0029] (Other embodiments) Although the present invention has been described above by way of the embodiment, the description and drawings forming part of this disclosure should not be understood as limiting the present invention. Various alternative embodiments, examples and operating techniques will become apparent to those skilled in the art from this disclosure.
[0030] For example, in the above description, the cross-sectional shape of the probe 1 is rectangular, but the cross-sectional shape of the probe 1 may be other shapes. For example, the cross-sectional shape of the probe 1 may be polygonal other than rectangular. Regardless of the polygonal shape of the cross-sectional shape of the probe 1, as long as the side surface of the probe 1 facing opposite to the offset direction is not covered with the contact film 13, the probe 1 can be prevented from contacting the adjacent land.
[0031] In addition, in the above description, the connection region 123 is connected to the tip region 122 of the probe 1 covered with the contact film 13, but the contact film 13 does not need to cover the entire tip region 122. For example, a surface on which the contact film 13 is not formed may be provided in the tip region 122 on the opposite side to the surface on which the contact film 13 is formed and connected to the end face 131, and the tapered connection region 123 may be connected to the surface on which the contact film 13 is not formed.
[0032] Thus, it goes without saying that the present invention includes various embodiments that are not described above. [Explanation of symbols]
[0033] 1…Probe 10...Base material 11...First end 12…Second end 13...Contact membrane 20…Probe head 21…First guide plate 22…Second guide plate 23…Third guide plate 30...Substrate 31…Rand 100...Electrical connection device 121…Tip surface 122...Tip area 123…Connection area 131…End face S1…Side 1 S2…Side 2 S3…Side 3 S4…Side 4
Claims
1. A probe for use in testing electrical characteristics of an object to be tested, comprising: a columnar base material having a first end portion and a second end portion that come into contact with the object to be inspected during the inspection, and a cross section perpendicular to an axial direction of the base material being polygonal; a contact film covering the remaining side surfaces of the second end portion, excluding a side surface facing a first direction, of a plurality of side surfaces connected to the tip surface of the second end portion, and the tip surface of the second end portion; Equipped with The end surface covering the tip surface of the second end of the contact film is a plane perpendicular to the axial direction. probe.
2. The probe according to claim 1 , wherein corners of the end surface of the contact film are chamfered when viewed from the first direction.
3. The probe of claim 1 , wherein a region of the second end exposed outside the contact film and connected to a region covered by the contact film has a tapered shape in which the cross section of the base material gradually narrows toward the tip surface.
4. The probe of claim 1 , wherein a cross section of the base material perpendicular to the axial direction is rectangular.
5. The probe of claim 1 , wherein the contact film is more conductive than the base material.
6. a probe head having a configuration in which a first guide plate and a second guide plate, each of which has a guide hole formed therein, are disposed at a distance from each other; The probe according to claim 1 , which is inserted into the guide hole and held by the probe head. Equipped with for the guide holes through which the same probe penetrates, the positions of the guide holes of the second guide plate are offset from the guide holes of the first guide plate in an offset direction parallel to a main surface of the first guide plate, and the base material is held in a curved state between the first guide plate and the second guide plate; The electrical connection device, wherein the first direction is the offset direction.