Probe unit

Abstract

The probe unit of the present invention comprises: a plurality of first contact probes, each of which contacts an electrode of a contact object at one end side in a longitudinal direction; a second contact probe, which is connected to an external ground; a probe base, which holds the first contact probes and the second contact probes, wherein the probe base is formed with: a first hollow portion, which is inserted into and holds the first contact probes; a second hollow portion, which is inserted into and holds the second contact probes; a through hole, which is arranged around the first hollow portion, and the probe base has a conductive portion, which constitutes the through hole, and electrically connects the through hole to the second contact probe.

Description

Technical Field

[0001] The present invention relates to a probe unit for accommodating contact probes, which output / input signals to a specific circuit structure. Background Art

[0002] Conventionally, when conducting on-state detection or operating characteristic detection on a detection object such as a semiconductor integrated circuit or a liquid crystal panel, a probe unit is used. The probe unit comprises: a contact probe that provides an electrical connection between the detection object and a signal processing device for outputting a detection signal; and a probe holder that accommodates a plurality of the above-mentioned contact probes.

[0003] Typically, when high-frequency electrical signals are input or output, signal loss known as insertion loss occurs. To achieve high-speed, high-precision operation in a probe unit, it is important to reduce this insertion loss within the frequency domain used. For example, Patent Document 1 discloses a technique for providing an air layer around a contact probe to match characteristic impedance.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2012-98219 Summary of the Invention

[0005] However, in the technology disclosed in Patent Document 1, although the impedance of the central portion of the contact probe can be adjusted, the characteristic impedance of the tip and base ends cannot be adjusted.

[0006] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a probe unit capable of adjusting the characteristic impedance of the entire contact probe.

[0007] In order to solve the above problems and achieve the purpose, the probe unit of the present invention includes: a plurality of first contact probes, each of which contacts the electrode of the contact object at one end side in the length direction; a second contact probe, which is connected to the external ground; and a probe seat, which holds the first contact probe and the second contact probe, wherein the probe seat is formed with: a first hollow portion, which is inserted into and holds the first contact probe; a second hollow portion, which is inserted into and holds the second contact probe; and a through hole, which is arranged around the first hollow portion, and the probe seat has a conductive portion, which constitutes the through hole and electrically connects the through hole to the second contact probe.

[0008] Furthermore, according to the probe unit of the present invention, in the above invention, the conductive portion is provided on the through hole and the surface forming the opening end of the through hole.

[0009] Furthermore, according to the probe unit of the present invention, in the above invention, the through hole is formed in a stepped hole shape having a diameter that varies locally.

[0010] Furthermore, according to the probe unit of the present invention, in the above invention, the through-hole is formed in a stepped hole shape in which the positions of the central axes are different from each other.

[0011] Furthermore, according to the probe unit of the present invention, in the above invention, the probe seat is formed of one member.

[0012] Furthermore, according to the probe unit of the present invention, in the above invention, the probe seat is formed by stacking a plurality of members in a direction penetrating the first hollow portion.

[0013] According to the probe unit of the present invention, in the above invention, the through hole is formed by through holes formed in the plurality of members, and in at least one member, the through hole is formed into a stepped hole with a partially different diameter.

[0014] According to the probe unit of the present invention, in the above invention, the through hole is formed by through holes formed in the plurality of members, and in at least one member, the through hole is formed into a stepped hole with the central axis positions being different from each other.

[0015] In addition, according to the probe unit of the present invention, in the above invention, through holes constituting the through holes are respectively formed in the plurality of components, and at least a portion of the through holes formed in the components adjacent to each other in the stacking direction of the components overlap with each other when viewed from the through direction of the through holes.

[0016] Furthermore, according to the probe unit of the present invention, in the above invention, the opening of the through hole is formed in a long hole shape when viewed from the penetrating direction.

[0017] According to the present invention, there is an effect of being able to adjust the characteristic impedance of the entire contact probe. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a partial cross-sectional view showing the structure of the main part of the probe unit according to the first embodiment of the present invention.

[0019] Figure 2 It is a diagram for explaining the arrangement of through holes of the probe unit according to the first embodiment of the present invention.

[0020] Figure 3 This figure shows a state when a semiconductor integrated circuit is inspected using the probe head according to the first embodiment of the present invention.

[0021] Figure 4 A diagram illustrating the arrangement of through holes in a probe unit according to a first modification of the first embodiment of the present invention.

[0022] Figure 5A diagram illustrating the arrangement of through holes in a probe unit according to a second modification of the first embodiment of the present invention.

[0023] Figure 6 A diagram illustrating the arrangement of through holes in a probe unit according to a third modification of the first embodiment of the present invention.

[0024] Figure 7 It is a cross-sectional view illustrating the structure of a main portion of a through hole of a probe unit according to a fourth modification of the first embodiment of the present invention.

[0025] Figure 8 It is a cross-sectional view illustrating the structure of a main portion of a through hole of a probe unit according to a fifth modification of the first embodiment of the present invention.

[0026] Figure 9 It is a cross-sectional view illustrating the structure of a main portion of a through hole of a probe unit according to a sixth modification of the first embodiment of the present invention.

[0027] Figure 10 It is a partial cross-sectional view showing the structure of the main part of the probe unit according to the second embodiment of the present invention.

[0028] Figure 11 It is a partial cross-sectional view showing the structure of the main part of the probe unit according to the third embodiment of the present invention. DETAILED DESCRIPTION

[0029] The following describes in detail the embodiments of the present invention with reference to the accompanying drawings. The present invention is not limited to the following embodiments. Furthermore, the figures referenced in the following description merely schematically illustrate shapes, sizes, and positional relationships to facilitate understanding of the present invention. Therefore, the present invention is not limited to the shapes, sizes, and positional relationships illustrated in the figures.

[0030] Implementation Method 1

[0031] Figure 1 It is a partial cross-sectional view showing the structure of the main part of the probe unit according to the first embodiment of the present invention. Figure 1 The probe unit 1 shown is a device used when performing electrical characteristic detection on a semiconductor integrated circuit as a detection object, and is a device that electrically connects a semiconductor integrated circuit (semiconductor integrated circuit 100 described later) and a circuit substrate (circuit substrate 200 described later) used to output detection signals to the semiconductor integrated circuit.

[0032] The probe unit 1 contacts two different contacted objects at its ends in the longitudinal direction, namely, a semiconductor integrated circuit 100 and a circuit substrate 200. The probe unit 1 includes: a conductive signal contact probe 2A (hereinafter referred to as "signal probe 2A") for conducting a test signal; a ground contact probe 2B (hereinafter referred to as "ground probe 2B") for connecting to an external ground electrode; and a probe holder 3 for accommodating and retaining the signal probe 2A and ground probe 2B according to a predetermined pattern. Furthermore, the probe unit 1 may include a holder member disposed around the probe holder 3 and configured to prevent positional deviation of the semiconductor integrated circuit during testing.

[0033] The signal probe 2A is formed of a conductive material and includes a first plunger 21, which contacts an electrode in the semiconductor integrated circuit to which a test signal is input during testing of the semiconductor integrated circuit; a second plunger 22, which contacts an electrode on a circuit board equipped with a test circuit to which a test signal is output; and a spring member 23, disposed between the first and second plungers 21, 22 to extend and retractably connect the first and second plungers 21, 22. The first and second plungers 21, 22, and spring member 23 that constitute the signal probe 2A are coaxial. Figure 1 In the signal probe 2A shown, the longitudinal axes (central axes) of the first plunger 21, the second plunger 22, and the spring member 23 are aligned with the axis N. P consistent.

[0034] When the signal probe 2A contacts the semiconductor integrated circuit, the spring member 23 expands and contracts to mitigate the impact on the semiconductor integrated circuit's connection electrodes, while also applying a load to the semiconductor integrated circuit and the circuit substrate. In the following description, the signal probe 2A is referred to as having a tip end in contact with the semiconductor integrated circuit's electrodes, and a base end on the side opposite the semiconductor integrated circuit's side in the axial direction. Furthermore, when defining a tip end and a base end within a plunger, the plunger in contact with the semiconductor integrated circuit is referred to as the tip end, and the side opposite the semiconductor integrated circuit's side in the axial direction is referred to as the base end. Furthermore, the plunger in contact with the circuit substrate is referred to as the tip end, and the side opposite the circuit substrate's side in the axial direction is referred to as the base end.

[0035] The first plunger 21 is movable in the axial direction by the expansion and contraction of the spring member 23. During testing, the spring force of the spring member 23 forces the first plunger 21 toward the semiconductor integrated circuit, thereby contacting the semiconductor integrated circuit's electrodes. Furthermore, the second plunger 22 is movable in the axial direction by the expansion and contraction of the spring member 23. The spring force of the spring member 23 forces the second plunger 22 toward the circuit board, thereby contacting the circuit board's electrodes.

[0036] The spring member 23 has a tightly wound portion 23a on the first plunger 21 side and a loosely wound portion 23b on the second plunger 22 side. The end of the tightly wound portion 23a is connected to the first plunger 21. The end of the loosely wound portion 23b is connected to the second plunger 22. The first and second plungers 21, 22, and spring member 23 are engaged by the coiling force of the springs and / or joined by welding.

[0037] The ground probe 2B has the same structure as the signal probe 2A. Specifically, the ground probe 2B is made of a conductive material and includes a first plunger 21, which contacts the ground electrode of the semiconductor integrated circuit during testing; a second plunger 22, which contacts the ground electrode of the circuit board; and a spring member 23, disposed between the first and second plungers 21, 22, to retractably connect the first and second plungers 21, 22. The first and second plungers 21, 22, and spring member 23 that constitute the ground probe 2B are coaxial. Figure 1 In the grounding probe 2B shown, the longitudinal axes (central axes) of the first plunger 21, the second plunger 22, and the spring member 23 are aligned with the axis N. P consistent.

[0038] The probe base 3 is formed by stacking a first member 31, a second member 32, a third member 33, and a fourth member 34 formed of an insulating material such as resin, machinable ceramic, or silicon. Figure 1 In the probe base 3 shown, the third member 33, the first member 31, the second member 32, and the fourth member 34 are stacked in this order from the top of the figure. The first member 31 to the fourth member 34 are fixed by known means such as screwing or bonding.

[0039] The probe base 3 has a hollow portion 35 for accommodating the plurality of signal probes 2A and a hollow portion 36 for accommodating the plurality of ground probes 2B. Furthermore, the probe base 3 has a plurality of through holes 37 formed around the signal probes 2A.

[0040] In the first member 31, a plating process is applied to the surface forming the surface of the first member 31. A conductive material is used in the plating process. Therefore, a first conductive film 31a and a second conductive film 31b are formed on the surface of the first member 31. In addition, the first conductive film 31a is formed on the surface of the forming portion including the through hole 37 except the hollow portion 35. In addition, the second conductive film 31b is formed on the surface of the forming portion of the hollow portion 35. The first conductive film 31a and the second conductive film 31b are separated from each other to ensure insulation. Figure 1In the example shown, the membrane is separated by cutting away a portion of the membrane.

[0041] Similar to the first member 31, the second through fourth members 32 to 34 are plated on their surfaces, excluding the portion forming the inner circumference of the hollow portion 35. A first conductive film 32a and a second conductive film 32b are formed on the surface of the second member 32. A first conductive film 33a and a second conductive film 33b are formed on the surface of the third member 33. A first conductive film 34a and a second conductive film 34b are formed on the surface of the fourth member 34. The first conductive films 32a to 34a are formed on the surface of the portion forming the through-hole 37, excluding the hollow portion 35. Furthermore, the second conductive films 32b to 34b are formed on the surface of the portion forming the hollow portion 35. At least a portion of the first conductive films 31a to 34a constitutes a conductive portion.

[0042] Therefore, in the probe receptacle 3 formed by laminating the first to fourth members 31 to 34 , a conductive film exists on the boundaries between the respective members and on the outer surfaces.

[0043] Hollow portion 35 is formed by aligning the axes of through-holes formed in first to fourth members 31 to 34. Second conductive films 31b to 34b are formed on the inner circumference of hollow portion 35, forming a conductive inner circumference. Hollow portion 35 extends in the stacking direction of first to fourth members 31 to 34.

[0044] The hollow portion 36 is formed by aligning the axes of the through holes formed in the first to fourth members 31 to 34. In the hollow portion 36, first conductive films 31a to 34a are formed on the inner peripheral surface to form a conductive inner peripheral surface.

[0045] The locations of hollow portions 35 and 36 are determined by the wiring pattern of the semiconductor integrated circuit. Both hollow portions 35 and 36 have stepped, stepped diameters that vary along the entire length of the probe holder. Specifically, each holder hole consists of a small-diameter portion and a large-diameter portion. The small-diameter portion opens onto the end surface of the probe holder 3, while the large-diameter portion has a larger diameter than the small-diameter portion. Figure 1 In the probe holder 3 shown, steps are formed at the boundaries between the first and third members 31 and 33, and between the second and fourth members 32 and 34. The shape of each holder hole is determined by the structure of the signal probe 2A and ground probe 2B it accommodates.

[0046] The first plunger 21 of the signal probe 2A has a function of preventing the signal probe 2A from falling off the probe base 3 by having its flange abut against the wall surface of the third member 33. Furthermore, the second plunger 22 has a function of preventing the signal probe 2A from falling off the probe base 3 by having its flange abut against the wall surface of the fourth member 34.

[0047] The first plunger 21 of the grounding probe 2B has the function of preventing the grounding probe 2B from falling off the probe holder 3 by causing the flange to abut against the wall surface of the third member 33. Furthermore, the second plunger 22 has the function of preventing the grounding probe 2B from falling off the probe holder 3 by causing the flange to abut against the wall surface of the fourth member 34.

[0048] The through hole 37 is formed by aligning the axes of the through holes formed in the first to fourth members 31 to 34. That is, the through hole 37 is provided from the surface on the front end side to the surface on the base end side of the signal probe 2A in the probe holder 3. Figure 1 In the through holes 37 shown, the central axis of each through hole is aligned with the axis N. T The opening of the through hole 37 in a direction perpendicular to the penetration direction is circular. The first conductive films 31a to 34a are formed on the inner peripheral surface of the through hole 37 to form a conductive inner peripheral surface.

[0049] The through-hole 37 forms a cylindrical hollow space and is formed in one or more locations around the signal probe 2A. In the first embodiment, an example is described in which eight through-holes 37 are formed around one signal probe 2A. Figure 2 This figure is a diagram for explaining the arrangement of the through-holes of the probe unit according to the first embodiment of the present invention. For example, the arrangement position of the signal probe 2A (axis N P ) as the center, eight through holes 37 are set at equal intervals. Figure 2 The diameters of the through holes 37 are the same, and the through holes 37 are aligned with the axis N. P The shortest distance between them is the same distance d1. That is, the circle passing through the centers of all the through holes 37 ( Figure 2 The center of the signal probe 2A (axis N P The through-hole group formed by all the through-holes 37 has a coaxial structure with respect to the signal probe 2A.

[0050] In the first embodiment, the arrangement position, number, and size of each through hole formed by the through holes 37 are determined so that the characteristic impedance when the signal probe 2A and the ground probe 2B are considered as one transmission path becomes a predetermined value (eg, 50Ω).

[0051] Figure 3This diagram shows the state of the probe unit 1 during testing of a semiconductor integrated circuit 100. During testing, the first plunger 21 of the signal probe 2A contacts the signal detection electrode 101 of the semiconductor integrated circuit 100, and the second plunger 22 contacts the signal detection electrode 201 of the circuit board 200. Meanwhile, the first plunger 21 of the ground probe 2B contacts the ground electrode 102 of the semiconductor integrated circuit 100, and the second plunger 22 contacts the ground electrode 202 of the circuit board 200. During testing of the semiconductor integrated circuit 100, the contact load from the semiconductor integrated circuit 100 compresses the spring member 23.

[0052] During testing, the test signal supplied from the circuit substrate 200 to the semiconductor integrated circuit 100 travels, for example, from the electrode 201 of the circuit substrate 200, through the second plunger 22 of the signal probe 2A, the tightly wound portion 23a (or the second conductive film), and the first plunger 21, ultimately reaching the electrode 101 of the semiconductor integrated circuit 100. As described above, in the signal probe 2A, since the first plunger 21 and the second plunger 22 are electrically connected via the tightly wound portion 23a, the conduction path of the electrical signal can be minimized. This prevents the signal from flowing to the loosely wound portion 23b during testing, reducing resistance and inductance. In this case, the path through the second plunger 22, the second conductive film, and the first plunger 21 allows the signal to be transmitted without passing through the spring member 23.

[0053] Furthermore, the first plunger 21 of the grounding probe 2B contacts the first conductive film 33a or 31a. Meanwhile, the second plunger 22 of the grounding probe 2B contacts the first conductive film 34a or 32a. Furthermore, the spring member 23 of the grounding probe 2B contacts the first conductive film 31a or 32a.

[0054] Generally, in electronic circuits processing AC signals, it is known that where wiring lines with different impedances connect, signals are reflected by an amount corresponding to the ratio of the different impedances, hindering signal transmission. This applies equally to the relationship between the semiconductor integrated circuit 100 and the signal probe 2A. When the characteristic impedance of the semiconductor integrated circuit 100 and the characteristic impedance of the signal probe 2A differ significantly, electrical signal loss occurs, and the waveform of the electrical signal is distorted.

[0055] Furthermore, due to differences in characteristic impedance, the proportion of signal reflections generated at the connection location increases as the speed, i.e., the frequency, of the semiconductor integrated circuit 100 increases. Therefore, when manufacturing the probe unit 1 for a semiconductor integrated circuit 100 driven at a high frequency, it is important to precisely adjust the impedance so that the characteristic impedance of the signal probe 2A matches that of the semiconductor integrated circuit 100.

[0056] However, changing the shape of the signal probe 2A is not easy from the perspective of impedance matching. The signal probe 2A is inherently limited by its outer diameter, which is limited to less than 1 mm, and its complex shape, consisting of the first plunger 21, the second plunger 22, and the spring member 23. Therefore, changing the shape to one suitable for impedance matching is difficult from a design and manufacturing perspective.

[0057] Therefore, in this embodiment, rather than changing the structure of the signal probe 2A, a through-hole 37 is provided around the first plunger 21, the second plunger 22, and the spring member 23 to adjust the characteristic impedance. This structure allows the signal probe 2A to be used in conjunction with conventional structures. For example, the same probe as the conventional ground probe 2B can be used as the signal probe 2A.

[0058] Furthermore, in the present embodiment, since it is not necessary to change the shape of the signal probe 2A to one suitable for impedance matching, the degree of freedom in the shape of the probe to be used can be increased.

[0059] Furthermore, in this first embodiment, through-holes 37 are provided around the signal probe 2A, extending from the tip end surface of the signal probe 2A to the base end surface of the probe holder 3. This allows adjustment of the characteristic impedance of the tip and base ends of the signal probe 2A. Specifically, the characteristic impedance can be adjusted by adjusting the number of through-holes, the diameter of the through-holes, and the arrangement of the through-holes (their distance from the signal probe 2A). Furthermore, by surrounding the signal probe 2A with multiple through-holes 37, the signal probe 2A is less susceptible to external influences such as noise and can reduce energy loss caused by energy leakage to the outside.

[0060] In the first embodiment described above, through-holes 37 are arranged around signal probe 2A and connected to an external ground via ground probe 2B. According to this first embodiment, the characteristic impedance of the tip and base of signal probe 2A can be adjusted by indirectly connecting through-holes 37 to an external ground. According to this first embodiment, the characteristic impedance of the entire signal probe 2A, including the tip, can be adjusted. Furthermore, according to this first embodiment, by adjusting the position of the through-holes, the ground position can be adjusted in a direction perpendicular to the axial direction of signal probe 2A.

[0061] Furthermore, according to the first embodiment described above, since the outer surface of the probe holder 3 is covered with the conductive film, it has excellent high-frequency characteristics compared to a case where no plating process is applied.

[0062] Furthermore, according to the first embodiment described above, since the characteristic impedance can be adjusted by the through-hole, the degree of freedom in arrangement of the grounding probe 2B can be improved.

[0063] Furthermore, in the above-described first embodiment, the first conductive films 33 a and 34 a may be connected to the external ground.

[0064] In the above-mentioned first embodiment, the axis N of the signal probe has been described. P Although this is an example in which a plurality of through holes are arranged symmetrically, an asymmetrical arrangement is also possible.

[0065] In the first embodiment, the example of evenly arranging a plurality of through holes relative to one signal probe has been described, but the through holes may be unevenly arranged. In this case, the unevenness may be the axis N of the signal probe. P The circumferential distance of a circle centered at a point on the axis is not uniform, and can also be the distance from the axis N P The shortest distances (the above-mentioned distance d1 ) may be unequal to each other, or both of them may exist.

[0066] Furthermore, in the first embodiment, an example in which a conductive film is formed on each member of the probe base 3 has been described. However, a conductive plate, sheet, film, etc. that is sufficiently thinner than the thickness of the member may be used instead of the film.

[0067] Furthermore, in the first embodiment, the second conductive films 31b to 34b are formed on the surface of the hollow portion 35 to form conductive through-holes. However, the second conductive film may not be formed and the inner peripheral surface may be an insulating surface.

[0068] Modification 1

[0069] Figure 4 This figure illustrates the arrangement of through-holes in a probe unit according to Modification 1 of Embodiment 1 of the present invention. In the probe unit according to Modification 1, the dimensions of some through-holes in the probe base 3 are different. The remaining configuration is identical to that of the probe unit 1, and therefore its description is omitted.

[0070] In the probe holder of the modification 1, six through holes 37 and two through holes 37A are formed around the signal probes 2A. Figure 4 The three groups of through holes 37 are arranged to be spaced apart from the axis N. P They face each other, and the through holes 37A are arranged across the axis N. P And examples facing each other.

[0071] Through-hole 37A is formed by aligning the axes of the through-holes formed in first to fourth members 31 to 34. Through-hole 37A forms a cylindrical hollow space. The opening perpendicular to the through-hole direction is circular. Through-hole 37A has a conductive film (such as the first conductive films 31a to 34a described above) formed on its inner circumference, making its inner circumference conductive. The diameter of through-hole 37A is larger than that of through-hole 37.

[0072] The through holes 37 and 37A are arranged so that the center of each through hole passes through the axis N of the signal probe 2A. P The circle centered at ( Figure 4 In addition, the through hole 37A is aligned with the axis N P The shortest distance d2 between the through hole 37 and the axis N P The shortest distance d1 between them is short.

[0073] As in this first variation, through-holes 37 and 37A of different sizes are arranged around the periphery of the signal probe 2A, and are connected to an external ground via the ground probe 2B. In this first variation, as in the first embodiment, the characteristic impedance of the tip and base of the signal probe 2A can be adjusted by indirectly connecting the through-holes 37 and 37A to the external ground.

[0074] Modification 2

[0075] Figure 5 This figure illustrates the arrangement of through-holes in a probe unit according to a second variation of embodiment 1 of the present invention. In the probe unit according to the second variation, the size and arrangement of some through-holes in the probe base 3 are different. The remaining structure is identical to that of the probe unit 1, and therefore its description is omitted.

[0076] In the probe holder of the second modification, six through holes 37 and two through holes 37A are formed around the signal probes 2A. Figure 5 The three groups of through holes 37 are arranged to be spaced apart from the axis N. P They face each other, and the through holes 37A are arranged across the axis N. P And examples facing each other.

[0077] The through holes 37 and 37A are arranged so that the through hole 37 is aligned with the axis N. P The shortest distance between the through hole 37A and the axis N P The shortest distance between them is the same distance d1.

[0078] As in this second variation, through-holes 37 and 37A of different sizes are arranged around the periphery of the signal probe 2A, and are connected to an external ground via the ground probe 2B. In this second variation, as in the first embodiment, the characteristic impedance of the tip and base of the signal probe 2A can be adjusted by indirectly connecting the through-holes 37 and 37A to the external ground.

[0079] Modification 3

[0080] Figure 6 This figure illustrates the arrangement of through-holes in a probe unit according to a third variation of embodiment 1 of the present invention. In the probe unit according to the third variation, the size and arrangement of some through-holes in the probe base 3 are different. The remaining structure is identical to that of the probe unit 1, and therefore its description is omitted.

[0081] In the probe holder of the modification 3, eight through holes 37B are formed around the signal probes 2A. Figure 6 The four through holes 37B are arranged to be spaced from each other by the axis N. P And examples facing each other respectively.

[0082] The through holes 37B are formed into an elongated hole shape when viewed from the through direction. The through holes 37B are arranged so that the center of gravity of each through hole passes through the axis N of the signal probe 2A. P The circle centered at ( Figure 6 A conductive film (eg, the first conductive films 31a to 34a described above) is also formed on the inner peripheral surface of the through hole 37B, so that the inner peripheral surface has conductivity.

[0083] As in this third variation, multiple through-holes 37B are arranged around the signal probe 2A, and are connected to an external ground via the ground probe 2B. In this third variation, as in the first embodiment, the characteristic impedance of the tip and base of the signal probe 2A can be adjusted by indirectly connecting to the external ground through the through-holes 37B.

[0084] Furthermore, in Modification 3, since the opening of through-hole 37B is formed into an elongated hole, the area surrounding signal probe 2A by through-hole 37B is expanded compared to through-holes 37 and 37A. By forming the through-hole into a shape other than a circle, the degree of freedom in adjusting the characteristic impedance is increased, resulting in improved high-frequency characteristics of the probe unit. Furthermore, by expanding the surrounding area, energy loss caused by energy outflow can be further reduced.

[0085] Modification 4

[0086] Figure 7This is a cross-sectional view illustrating the structure of the main portion of the through hole of the probe unit according to Modification 4 of Embodiment 1 of the present invention. The probe unit according to Modification 4 differs in the shape of the through hole in the probe holder 3. The remaining structure is the same as that of the probe unit 1, so its description is omitted.

[0087] The through-holes of Modification 4 are formed by interconnecting the through-holes formed in the first to fourth members 31 to 34. A conductive film (e.g., the first conductive films 31a to 34a described above) is formed on the inner circumference of the through-holes to form a conductive inner circumference. The diameters of the through-holes vary in some areas. Specifically, for example, the diameter Q1 of the through-hole 37a formed in the third member 33 differs from the diameter Q2 of the through-hole 37b formed in the first member 31. The central axis N1 of the through-hole 37a and the central axis N2 of the through-hole 37b are connected to each other in a straight line.

[0088] As in this fourth variation, by forming stepped through-holes around the signal probe 2A and connecting to the external ground via the ground probe 2B, the same effects as those of the first embodiment can be obtained, and the characteristic impedance can be adjusted according to the shape of the signal probe 2A.

[0089] Modification 5

[0090] Figure 8 This is a cross-sectional view illustrating the structure of the main portion of the through hole of the probe unit according to Modification 5 of Embodiment 1 of the present invention. The probe unit according to Modification 5 differs in the shape of the through hole in the probe holder 3. The remaining structure is the same as that of the probe unit 1, and therefore its description is omitted.

[0091] The through-hole of Modification 5 is formed by interconnecting the through-holes formed in the first to fourth members 31 to 34. In the through-hole, a conductive film (e.g., the first conductive films 31a to 34a described above) is formed on the inner circumference to form a conductive inner circumference. The positions of the axes of the through-holes are locally different. Specifically, for example, the positions of the center axis N1 of the through-hole 37c formed in the third member 33 and the center axis N2 of the through-hole 37d formed in the first member 31 are different. In addition, the diameter Q3 of the through-hole 37c and the diameter Q4 of the through-hole 37d are the same diameter. As described above, the through-hole of Modification 5 is formed by through-holes whose center axis positions are locally different. In this case, when the through-hole is viewed in the stacking direction of the first to fourth members 31 to 34, at least a portion of the through-holes formed in the members adjacent to each other in the stacking direction overlap. The through-hole is formed by interconnecting at least a portion of the through-holes formed in the respective members.

[0092] As in this fifth variation, a stepped through hole with a partially offset through-hole axis is arranged around the signal probe 2A, and connected to an external ground via the ground probe 2B. This achieves the same effects as in the first embodiment, and allows the characteristic impedance to be adjusted according to the shape of the signal probe 2A.

[0093] Modification 6

[0094] Figure 9 This is a cross-sectional view illustrating the structure of the main portion of the through hole of the probe unit according to Modification 6 of Embodiment 1 of the present invention. The probe unit according to Modification 6 differs in the shape of the through hole in the probe holder 3. The remaining structure is the same as that of the probe unit 1, so its description is omitted.

[0095] The through-holes of Modification 6 are formed by interconnecting the through-holes formed in the first to fourth members 31 to 34. In the through-holes, a conductive film (e.g., the first conductive films 31a to 34a described above) is formed on the inner circumference to form a conductive inner circumference. The diameter and axis positions of the through-holes are partially different. Specifically, for example, the diameter Q5 of the through-hole 37e formed in the third member 33 is different from the diameter Q6 of the through-hole 37f formed in the first member 31. In addition, the center axis N1 of the through-hole 37e and the center axis N2 of the through-hole 37f are located at different positions.

[0096] As in this sixth variation, a stepped through hole is arranged around the signal probe 2A, in which a portion of the through holes has a different diameter and an axis is offset, and is connected to an external ground via the ground probe 2B. This allows the same effect as in the first embodiment to be achieved, and the characteristic impedance can be adjusted according to the shape of the signal probe 2A.

[0097] It is also possible to appropriately combine the through-hole structures of Modifications 1 to 6. For example, the signal probes arranged in the same probe holder may have at least a portion of their shapes and arrangements different from each other.

[0098] Implementation Method 2

[0099] Then refer to Figure 10 Implementation method 2 will be described. Figure 10 This is a partial cross-sectional view showing the structure of the main part of the probe unit according to Embodiment 2 of the present invention. The probe unit according to Embodiment 2 includes a probe base 3A in place of the probe base 3. The remaining structure is the same as that of the probe unit 1, and therefore its description is omitted.

[0100] The probe base 3A is formed from a single component made of an insulating material such as resin, machinable ceramic, or silicon. The probe base 3A includes a hollow portion 35 that creates a space for accommodating multiple signal probes 2A, and a hollow portion (the aforementioned hollow portion 36) that creates a space for accommodating multiple ground probes 2B. Hollow portions 35 and 36 are shaped like holes with a diameter that allows for insertion and removal of the contact probes while preventing them from falling out. Furthermore, the probe base 3A includes multiple through-holes 38 formed around the signal probes 2A.

[0101] The probe base 3A is plated on its surface. A conductive material is used for the plating process. Consequently, a first conductive film 3a and a second conductive film 3b are formed on the surface of the probe base 3A. The first conductive film 3a is formed on the surface of the portion excluding the hollow portion 35, including the portion where the through-hole 38 is formed. Furthermore, the second conductive film 3b is formed on the surface of the portion where the hollow portion 35 is formed. The first conductive film 3a and the second conductive film 3b are separated from each other to ensure insulation.

[0102] The through hole 38 is a through hole with a circular opening perpendicular to the through direction and a partially different diameter. Specifically, the through hole 38 has a first hole portion 38a formed on one surface side (on the Figure 10 The second hole portion 38b is formed on the other surface side (in the middle of the first plunger 21 extending side); Figure 10 The through hole 38 has a first conductive film 3a formed on its inner circumference, forming a conductive inner surface. Furthermore, the central axes of the first, second, and third holes 38a, 38b, and 38c are connected in a straight line.

[0103] The through-holes 38 form cylindrical hollow spaces with partially different diameters and are formed in plurality around the signal probe 2A. For example, as in the first embodiment, eight through-holes 38 are formed around one signal probe 2A.

[0104] In the second embodiment described above, through-holes 38 are arranged around signal probe 2A and connected to an external ground via ground probe 2B. As described above, according to the second embodiment, the characteristic impedance of the tip and base of signal probe 2A can be adjusted by indirectly connecting through-holes 38 to an external ground. According to the second embodiment, the characteristic impedance of the entire signal probe 2A, including the tip, can be adjusted. Furthermore, according to the second embodiment, by adjusting the position of the through-holes, the ground position can be adjusted in a direction perpendicular to the axial direction relative to signal probe 2A.

[0105] Furthermore, in the second embodiment, since the diameter of the through hole of the through hole 38 is locally different, the characteristic impedance can be adjusted according to the shape of the signal probe 2A.

[0106] Implementation 3

[0107] Then refer to Figure 11 Implementation method 3 will be described. Figure 11 This is a partial cross-sectional view showing the structure of the main part of the probe unit according to Embodiment 3 of the present invention. The probe unit according to Embodiment 3 includes a probe base 4 in place of the probe base 3. The remaining structure is the same as that of the probe unit 1, and therefore its description is omitted.

[0108] The probe base 4 is formed by laminating a first member 41 and a second member 42 formed of an insulating material such as resin, machinable ceramic, or silicon. Figure 11 The probe base 4 shown is stacked in the order of a first member 41 and a second member 42 from the upper side of the figure. The first member 41 and the second member 42 are fixed by screws or bonding or other known methods.

[0109] The probe base 4 includes a hollow portion 35 for accommodating a plurality of signal probes 2A and a hollow portion (not shown) for accommodating a plurality of ground probes 2B. Furthermore, the probe base 4 includes a plurality of through holes 43 formed around the signal probes 2A.

[0110] The first member 41 is plated on the surface forming the surface of the first member 41. A conductive material is used for the plating. Consequently, a first conductive film 41a and a second conductive film 41b are formed on the surface of the first member 41. The first conductive film 41a is formed on the surface of the portion forming the through-hole 43, excluding the hollow portion 35. Furthermore, the second conductive film 41b is formed on the surface of the portion forming the hollow portion 35. The first and second conductive films 41a and 41b are separated from each other to ensure insulation.

[0111] In the second member 42, similar to the first member 41, the surface forming the surface of the second member 42 is plated. A first conductive film 42a and a second conductive film 42b are formed on the surface of the second member 42. The first conductive film 42a is formed on the surface of the portion forming the through-hole 43, excluding the hollow portion 35. Furthermore, the second conductive film 42b is formed on the surface of the portion forming the hollow portion 35. The first and second conductive films 42a and 42b are separated from each other to ensure insulation.

[0112] Therefore, in the probe seat 4 formed by laminating the first member 41 and the second member 42 , a conductive film exists on the boundaries between the respective members and on the outer surfaces.

[0113] The hollow portion 35 is formed by aligning the axes of the through holes formed in the first member 41 and the second member 42. In the hollow portion 35, second conductive films 41b and 42b are formed on the inner peripheral surface to form a conductive inner peripheral surface.

[0114] The through hole 43 is a through hole with a circular opening perpendicular to the through direction and a stepped central axis. Specifically, the through hole 43 has a first hole portion 43a formed on one surface side of the probe holder 4 (at Figure 11 The second hole portion 43b is formed on the other surface side (on the side where the first plunger 21 extends); Figure 11 The third hole portion 43c is provided between the first hole portion 43a and the second hole portion 43b. The opening diameters of the first hole portion 43a, the second hole portion 43b, and the third hole portion 43c are the same. In addition, within the range where the adjacent holes are connected to each other, the center axis N of the first hole portion 43a and the second hole portion 43b is T1 、N T2 and the central axis N of the third hole portion 43c T3 In the through hole 43, the first conductive films 41a and 42a are formed on the inner peripheral surface to form a conductive inner peripheral surface.

[0115] The through holes 43 form a stepped cylindrical hollow space, and a plurality of through holes 43 are formed around the signal probe 2A. For example, as in the first embodiment, eight through holes 43 may be formed around one signal probe 2A.

[0116] In the third embodiment described above, through-holes 43 are arranged around the signal probe 2A and connected to an external ground via the ground probe 2B. Thus, according to the third embodiment, the characteristic impedance of the tip and base of the signal probe 2A can be adjusted via the through-holes 43 indirectly connected to the external ground. According to the third embodiment, the overall characteristic impedance, including the ends of the signal probe 2A, can be adjusted. Furthermore, according to the third embodiment, by adjusting the position of the through-holes, the ground position relative to the signal probe 2A in a direction perpendicular to the axial direction can be adjusted.

[0117] Furthermore, in the third embodiment, the positions of the central axes of the through holes of the through hole 43 are partially different, and thus the characteristic impedance can be adjusted according to the shape of the signal probe 2A.

[0118] The above-described embodiments 1 to 3 and their modifications can be appropriately combined. In addition, for each contact probe, the configuration or shape of the through-holes in the embodiment and modifications 1 to 3 can be individually selected and adopted.

[0119] The contact probe structure described here is merely an example; various known probe types are applicable. For example, the probe is not limited to the plunger and coil spring configuration described above. Other probe types include probes with tubular members, pogo pins, solid conductive members, conductive tubular components, wire probes that can be bent into a bow shape to provide a load, and connectors for connecting electrical contacts. These probes can also be appropriately combined.

[0120] Furthermore, the probe seats of the above-mentioned embodiments 1 to 3 and their modifications are configured by stacking four or two members and by one member, but may be configured by stacking three or five or more members.

[0121] Furthermore, in the above-mentioned embodiments 1 to 3 and their variations, the conductive film may be formed locally as long as it can electrically connect the through hole and the grounding probe 2B, rather than being formed on the entire surface of the member of the probe holder 3. For example, a structure may be adopted in which the conductive film is formed on the portion constituting the through hole and the member constituting the opening end of the through hole (e.g., Figure 1 The outer surface of the third member 33 and the fourth member 34 shown in FIG. In this case, the conductive film is electrically connected to the grounding probe 2B at least during the test.

[0122] As described above, the present invention may include various embodiments not described herein, and various design changes may be made without departing from the technical concept defined in the claims of the present application.

[0123] As described above, the probe unit of the present invention is suitable for adjusting the characteristic impedance of the entire contact probe.

[0124] Explanation of symbols

[0125] 1 Probe unit

[0126] 2A contact probe (signal probe)

[0127] 2B contact probe (ground probe)

[0128] 3, 3A, 3B probe holder

[0129] 3a, 31a to 34a, 41a, 42a First conductive film

[0130] 3b, 31b to 34b, 41b, 42b Second conductive film

[0131] 21 First plunger

[0132] 22 Second plunger

[0133] 23 Spring member

[0134] 23a Tightly wound section

[0135] 23b Loose winding part

[0136] 31, 41 First component

[0137] 32, 42 Second component

[0138] 33 Third component

[0139] 34 Fourth Component

[0140] 35, 36 hollow part

[0141] 37, 37A, 37B, 38, 43 through holes

[0142] 100 Semiconductor Integrated Circuits

[0143] 101, 102, 201, 202 electrodes

[0144] 200 circuit board

Claims

1. A probe unit, comprising: a plurality of first contact probes, each of which contacts an electrode of a contact target at one end side in a longitudinal direction; a second contact probe connected to an external ground; and a probe holder that holds the first contact probe and the second contact probe, The probe seat is formed with: a first hollow portion into which the first contact probe is inserted and held; a second hollow portion into which the second contact probe is inserted and held; and a through hole provided around the first hollow portion, The probe base has a conductive portion, which constitutes the through hole and electrically connects the through hole and the second contact probe.

2. The probe unit according to claim 1, wherein The conductive portion is provided on the through hole and a surface forming an opening end of the through hole.

3. The probe unit according to claim 1 or 2, wherein: The through hole is formed in a stepped hole shape with a diameter that varies locally.

4. The probe unit according to claim 1 or 2, wherein: The through holes are formed in stepped hole shapes whose central axis positions are different from each other.

5. The probe unit according to claim 1 or 2, wherein: The probe base is formed from one member. The probe unit according to claim 1 or 2, wherein: The probe seat is formed by stacking a plurality of members in a direction extending through the first hollow portion. The probe unit according to claim 6 , wherein: The through hole is formed by through holes formed in the plurality of components respectively. In at least one member, the through hole is formed in a stepped hole shape in which the diameter of the through hole is locally different. The probe unit according to claim 6 , wherein: The through hole is formed by through holes formed in the plurality of components respectively. In at least one member, the through hole is formed in a stepped hole shape in which positions of central axes of the through holes are different from each other.

9. The probe unit according to claim 6, wherein Through holes constituting the through holes are formed in each of the plurality of components. In the through-holes, at least a portion of the through-holes formed in the members adjacent to each other in the stacking direction of the members overlaps with each other when viewed in the penetrating direction of the through-holes.

10. The probe unit according to claim 1 or 2, wherein: The through hole has an opening shaped like a long hole when viewed from a penetrating direction.

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