JP2015081805A - Contact probe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact probe that can be arranged at a narrow pitch while suppressing deterioration of electrical characteristics.
A spiral spring portion 11 that connects a first end portion and a second end portion, and is disposed in the spring portion 11, one end is connected to the first end portion, and the other end is connected to the second end portion. And a core portion 13 which is disposed in the engagement hole H so as to freely advance and retract. Since the core portion 13 and the engagement hole H have cross-sectional shapes that interfere with each other by relatively rotating, the core portion 13 and the engagement hole H can be reliably secured by the rotational stress of the spring portion generated during overdrive. It is possible to prevent the electrical characteristics from deteriorating due to the contact and the current flowing through the spring portion 11. Further, it is possible to suppress the spring portion 11 from being deformed and bent during overdrive.

Description

  The present invention relates to a contact probe, and more particularly to a contact probe in which both ends are connected by a spiral spring portion.

  The probe card is configured by standing a large number of contact probes on a wiring board, and is used in a semiconductor device inspection process. Inspection of a semiconductor device is performed by bringing a contact probe on a probe card into contact with an electrode pad on a semiconductor wafer and conducting an integrated circuit formed on the semiconductor wafer with the outside. At that time, a process of pressing the contact probe against the electrode pad is performed in order to absorb the variation in the height of the contact probe and the electrode pad and to ensure that the contact probe is electrically connected to the electrode pad. This process is called overdrive, and the pressing distance is called overdrive amount.

  In recent years, with the high integration of semiconductor devices, the pitch of electrode pads formed on a semiconductor chip has been reduced. Correspondingly, the probe card is also required to have a narrower pitch of the contact probe. For this reason, methods for improving the vertical probe arranged so as to be perpendicular to the wiring board and realizing further narrow pitch have been proposed (for example, Patent Documents 1 and 2).

  Patent Document 1 describes a vertical probe that bends during overdrive and ensures electrical contact by the needle pressure at that time. If such vertical probes are arranged on the wiring board so that their bending directions coincide with each other, contact between the contact probes can be prevented. However, there is a problem in that adjacent contact probes come into contact when the amount of bending varies greatly depending on the unevenness of the electrode pad surface and the presence of foreign matter.

  Patent Document 2 describes a vertical probe having a spiral spring structure. By adopting a spring structure that is compressed in the axial direction at the time of overdrive, contact with an adjacent vertical probe can be suppressed. In addition, since a relatively large overdrive amount can be ensured, variations in the height of the contact probe and the electrode pad can be absorbed.

  However, this spring structure is manufactured by forming a nickel alloy plating layer on a cylindrical core wire, patterning the plating layer in a spiral shape, and then extracting the core wire. For this reason, it is necessary to manufacture and assemble a spring part and other parts separately, and the dispersion | variation and cost at the time of manufacture become a problem. In addition, when current flows through the spiral spring structure, an induced electromotive force is generated, and the electrical characteristics of the contact probe are deteriorated.

US Patent Application Publication No. 2010/0182030 JP 2010-281607 A

  In order to prevent the deterioration of the electrical characteristics in the contact probe adopting the spring structure, for example, it is conceivable that a core part is arranged in the spring so that a current flows through the core part. However, even if the core part is disposed in the elastic spring, there arises a problem that good electrical contact cannot be ensured between both ends of the core part and both ends of the spring structure. Furthermore, it is necessary to manufacture and assemble the spring structure and the core part separately, which causes variations in manufacturing and costs.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a contact probe that can be arranged at a narrow pitch while suppressing contact with adjacent contact probes. In particular, it is an object of the present invention to provide a contact probe that can be arranged at a narrow pitch while suppressing deterioration of electrical characteristics. It is another object of the present invention to provide a contact probe that can be arranged at a narrow pitch while ensuring a sufficient overdrive amount.

  A contact probe according to a first aspect of the present invention includes a spiral spring portion that connects a first end portion and a second end portion, and is disposed in the spring portion, one end is connected to the first end portion, and the other end is the first end. And a core portion disposed in the engagement hole at the two end portions so as to freely advance and retract. In a cross section intersecting the longitudinal direction of the core portion, a minimum diameter of a circle surrounding the cross section of the core portion is the engagement hole. It is comprised so that it may become larger than the maximum diameter of the circle | round | yen included in the cross section of this.

  When the test object is pressed against the contact probe from the axial direction and the helical spring portion is compressed, rotational stress about the axial direction is generated in the spring portion, and the first end portion and the second end portion are relative to each other. Rotate. One end of the core portion is connected to the first end portion, and the other end is inserted into the engagement hole of the second end portion so as to freely advance and retract. Therefore, the first end portion and the second end portion are relatively If it rotates, a core part and an engagement hole will also rotate relatively. In addition, since the minimum diameter of the circle surrounding the cross section of the core portion is larger than the maximum diameter of the circle included in the cross section of the engagement hole, the core portion is engaged when the core portion and the engagement hole rotate relatively. Contact with the hole. In other words, by inserting the core part into the engagement hole so as to be able to advance and retract, the spring part can be expanded and contracted to realize overdrive, while the spring part is compressed by the cross-sectional shape of the core part and the engagement hole. Good electrical contact can be ensured between the first end and the second end. As a result, it is possible to suppress deterioration of electrical characteristics due to current flowing through the spiral spring portion.

  Also, by adopting a spiral spring part and arranging the core part inside it, the deformation of the contact probe is limited in the expansion and contraction direction of the spring part and suppresses contact with the adjacent contact probe during overdrive be able to. Accordingly, it is possible to arrange the wiring board at a narrower pitch on the wiring board.

  The object to be inspected may be pressed on either the first end side or the second end side of the contact probe.

  In the contact probe according to the second aspect of the present invention, in addition to the above configuration, the cross section of the engagement hole is substantially rectangular, and the cross section of the core portion has a diagonal longer than the short side of the cross section of the engagement hole. Consists of polygons.

  By adopting such a configuration, if the first end portion and the second end portion are relatively rotated, the core portion and the engagement hole are reliably in contact with each other, and the first end portion and the Good electrical contact can be ensured between the two ends.

  A contact probe according to a third aspect of the present invention is configured such that, in addition to the above-described configuration, the core and the engagement hole contact each other in an elongated region extending in the longitudinal direction of the core by rotating relatively. Has been.

  By adopting such a configuration, the contact area between the core portion and the engagement hole can be increased, and the electrical resistance of the first end portion and the second end portion during overdrive can be reduced.

  The contact probe according to the present invention can be arranged at a narrow pitch while suppressing contact with adjacent contact probes. In particular, the contact probe according to the present invention includes a spiral spring portion, and when overdriving, a current can flow through the core portion in the spring portion, so that the electrical characteristics are deteriorated due to the current flowing through the spring portion. Can be suppressed. Therefore, it can arrange | position with a narrow pitch, suppressing the deterioration of an electrical property.

  Further, by disposing the core part in the spiral spring part, the deformation of the contact probe can be restricted in the extending and contracting direction of the spring part. For this reason, the stroke amount of a spring part can be adjusted and the amount of overdrive can be ensured. Therefore, it is possible to arrange with a narrow pitch while ensuring a sufficient overdrive amount.

It is the figure which showed one structural example of the probe card 100 by embodiment of this invention. It is the figure which showed the structural example of the contact probe 1 of FIG. FIG. 3 is a cross-sectional view illustrating a configuration example of the contact probe 1 in FIG. 2. It is sectional drawing which showed the structural example of the contact probe 1 of FIG. 2, and the cut surface at the time of cutting the contact probe 1 with a BB cutting line is shown. It is explanatory drawing which showed typically an example of operation | movement of the contact probe 1 of FIG. FIG. 3 is a diagram schematically showing an example of a method for manufacturing the contact probe 1 of FIG. 2, and shows a process of forming metal layers 42 and 44 and a sacrificial layer 45 for a lower gap on a substrate 40. FIG. 3 is a diagram schematically showing an example of a method for manufacturing the contact probe 1 of FIG. 2, and shows a process of forming metal layers 46 and 48 and a sacrificial layer 47 for the upper gap on the substrate 40. It is sectional drawing which showed the other structural example of the contact probe 1, and the case where the core part 13 has a different cross-sectional shape from the engagement hole H of the root part 12 is shown. It is sectional drawing which showed the other structural example of the contact probe 1, and the core part 13 and the engagement hole H which have a substantially L-shaped cross section are shown.

  FIG. 1 is a diagram showing a configuration example of a probe card 100 according to an embodiment of the present invention. (A) in the figure shows a state of the probe card 100 viewed from below, and (b) shows a state of viewing from the horizontal direction.

  This probe card 100 is a vertical needle type probe card, and is held by an ST (Space Transformer) substrate 2 on which a large number of contact probes 1 are arranged, and a probe device (not shown), and a tester device (not shown) is connected. The main board 3 is used.

  The main board 3 is a wiring board that is detachably attached to the probe device, for example, a circular PCB (printed circuit board), and is provided with a large number of external terminals T. The external terminal T is an input / output terminal for inputting / outputting a signal to / from the tester device, and is disposed on the peripheral edge of the main board 3. The ST substrate 2 is a wiring substrate for converting the wiring pitch, and is attached to the lower surface of the main substrate 3.

  The contact probe 1 is a probe that is brought into contact with a microelectrode on an inspection object, and is a vertical probe that has a substantially linear shape and is erected substantially vertically on the ST substrate 2. Each contact probe 1 is arranged in alignment with the electrode pad of the semiconductor integrated circuit to be inspected. In this example, the contact probes 1 are arranged in a matrix of 8 rows and 8 columns to form an array type probe card 100.

  The probe card 100 is held horizontally by the probe device. At this time, the contact probe 1 extends downward from the probe card 100 so that the longitudinal direction thereof is the vertical direction. In this state, when the inspection object is brought closer from below and the lower end of the contact probe 1 is brought into contact with the electrode pad of the semiconductor integrated circuit formed on the inspection object, the test signal is transmitted through the contact probe 1 and the tester device. Input / output can be performed between semiconductor integrated circuits.

  FIG. 2 is a diagram showing a configuration example of the contact probe 1 of FIG. FIG. 2A shows an enlarged view of the contact probe 1 of FIG. 1B, and FIG. 2B shows a state of the contact probe 1 of FIG. 2A viewed from the right side. ing. The contact probe 1 includes a needle tip portion 10, a spring portion 11, a root portion 12, and a core portion 13, and a core portion 13 is disposed in a spiral spring portion 11 that can expand and contract in the axial direction. In the present specification, the longitudinal direction of the contact probe 1 is simply referred to as “axial direction”.

  The needle tip portion 10 is one end portion of the contact probe 1 that is brought into contact with the inspection object, and a contact tip CT that is brought into contact with the electrode pad on the inspection object is provided at the tip thereof. The illustrated contact chip CT is composed of a plate-like member that protrudes from the lower end surface of the needle tip portion 10, and a bifurcated protrusion is formed from a V-shaped notch that widens downward in the axial direction. However, the shape of the contact chip CT can be appropriately determined according to the shape and material of the inspection object.

  The root portion 12 is the other end portion of the contact probe 1 fixed to the ST substrate 2 and is provided with an engagement hole H. The engagement hole H is a space in the root portion 12 that has an opening facing the internal space of the spring portion 11 and extends in the axial direction from the opening.

  The spring portion 11 is a coil spring extending in the axial direction, has a spiral shape that turns around its central axis, and connects the needle tip portion 10 and the root portion 12 provided at both ends thereof.

  The core portion 13 is an elongated guide shaft portion disposed in the internal space of the spring portion 11, the lower end thereof is connected to the needle tip portion 10, and the upper end portion thereof is inserted into the engagement hole H. It ’s easy to move forward and backward. By providing the core portion 13, it is possible to suppress the spring portion 11 from being bent during overdrive, and to restrict relative movement between the needle tip portion 10 and the root portion 12 in the axial direction.

  3 and 4 are cross-sectional views of the contact probe 1 of FIG. FIG. 3A shows a cut surface when the spring portion 11 of the contact probe 1 is cut along an A1-A1 cutting line that intersects the axial direction. FIG. 3B shows a cut surface when the root portion 12 of the contact probe 1 is cut by an A2-A2 cutting line that intersects the axial direction. FIG. 4 shows a cut surface when the contact probe 1 is cut by a BB cutting line parallel to the axial direction.

  As shown in FIG. 3A, when the spring portion 11 is cut and viewed in plan from the axial direction, an outer shape made of a substantially rectangular shape and an internal space made of a substantially rectangular shape can be observed. That is, the spring portion 11 is inclined in the axial direction, but has a shape that becomes a rectangular frame when viewed in plan.

  The rectangular frame of the spring part 11 is configured by alternately connecting the horizontal beam part 11A and the inclined beam part 11B. In a state where the contact probe 1 is set up in the vertical direction, the horizontal beam portion 11A extends in the horizontal direction, while the inclined beam portion 11B has an angle with respect to the horizontal direction. Further, the two inclined beam portions 11B connected to both ends of the same horizontal beam portion 11A have inclinations opposite to each other in the horizontal direction. By alternately connecting the horizontal beam portion 11A and the inclined beam portion 11B, a spiral spring portion 11 is formed (see FIGS. 2 and 4).

  The needle tip portion 10, the spring portion 11, the root portion 12, and the core portion 13 are formed by depositing metal on a sacrificial layer substrate on which a sacrificial layer is formed, as will be described later. At this time, the spring portion 11 and the core portion 13 are integrally formed in a state where the axial direction of the contact probe 1 is substantially parallel to the sacrificial layer substrate. The inclined beam portion 11B constituting the spring portion 11 is formed such that its longitudinal direction is parallel to the sacrificial layer substrate, and the horizontal beam portion 11A is formed so that its longitudinal direction is orthogonal to the sacrificial layer substrate.

Further, at the top of the rectangular frame, the beam joint portion 11C joining the horizontal beam portion 11A inclined beam portion 11B is in the axial thickness t ₁ is the horizontal beam portion 11A and the inclined beam portion 11B thickness t ₂ It is formed to be thicker (see FIG. 2). By increasing the thickness t ₁ of the beam joint portion 11C, it is possible to hardly occur a peeling interface at the beam joints 11C.

  If one round of the rectangular frame is one stage, the spring portion 11 is configured to have two or more stages. In particular, in order to secure a sufficient stroke amount at the time of overdrive and obtain a desired needle pressure, it is desirable that the number of turns of the spring portion 11 is 10 or more. For example, in order to ensure a stroke amount of about 100 μm, the spring portion 11 may be configured to have a winding number of about 100 to 200 steps.

  As shown in FIG. 3B, the core 13 and the engagement hole H are both substantially rectangular in cross section when cut by a cut surface orthogonal to the axial direction. Further, the length L1 of the short side constituting the rectangular cross section of the engagement hole H is shorter than the length L2 of the diagonal line of the rectangular cross section of the core portion 13. For this reason, when the core 13 and the engagement hole H are relatively rotated, the core 13 and the engagement hole H interfere with each other. That is, the core portion 13 and the engagement hole H are brought into contact with each other by relative rotation, and can no longer be relatively rotated.

  FIG. 5 is an explanatory view schematically showing an example of the operation of the contact probe 1 of FIG. (A) in the drawing shows a state in which the contact probe 1 is brought into contact with the electrode pad 4 by raising the movable stage 6 on which the semiconductor wafer 5 is placed. (B) in the drawing shows a state in which the core portion 13 and the root portion 12 are in contact with each other due to the rotational stress generated by compressing the spring portion 11.

  When inspecting an integrated circuit on a semiconductor wafer, overdrive is performed to push the contact probe 1 against the electrode pad 4 by raising the movable stage 6 beyond the position where the contact probe 1 starts to contact the electrode pad 4. . By this overdrive, it is possible to absorb variations in the height of the tip 10 of the contact probe 1 and the height of the electrode pad 4 and to ensure that all the contact probes 1 on the probe card 100 are electrically connected to the electrode pad 4. it can. Also, the needle pressure can be adjusted by adjusting the amount of overdrive.

  The spiral spring portion 11 is compressed in the axial direction during overdrive, and rotational stress about the axial direction is generated. The upper end of the spring part 11 is connected to the root part 12, and the root part 12 is fixed to the ST substrate 2. For this reason, the needle tip part 10 connected to the lower end of the spring part 11 is rotated by the rotational stress of the spring part 11. That is, at the time of overdrive, the needle tip portion 10 and the root portion 12 rotate relatively. As a result, the core portion 13 connected to the needle tip portion 10 rotates relative to the engagement hole H formed in the needle base portion 12.

  The core 13 and the engagement hole H have a cross-sectional shape that interferes with each other by relative rotation. For this reason, at the time of overdrive, the needle tip part 10 and the root part 12 can be brought into contact by utilizing the rotational stress of the spring part 11, and good electrical contact can be made between the tip part 10 and the root part 12. Can be obtained.

  13 c in the figure has the smallest diameter among the circles that can include the cross section of the core portion 13. Further, Hc in the figure has the maximum diameter among the circles that can be accommodated in the cross section of the engagement hole H. If a circle surrounding a certain shape is called an outer circle, and a circle included in a certain shape is called an inner circle, 13c is the minimum outer circle of the core 13, and Hc is the maximum of the engagement hole H. It becomes an inclusive circle.

  On the same cut surface when the contact probe 1 is cut along a cross-section that intersects in the axial direction, the diameter 13d of the smallest outer circle 13c of the core portion 13 is larger than the diameter Hd of the largest inner circle Hc of the engagement hole H. Is too large, the core portion 13 cannot freely rotate in the engagement hole H. In this case, when the core portion 13 and the engagement hole H rotate relative to each other over a certain angle due to the rotational stress of the spring portion 11 during overdrive, the core portion 13 and the engagement hole H interfere with each other. The parts are in contact. Such a relationship is established even when the cross section of the core portion 13 and the engagement hole H has a shape other than a rectangle.

  Furthermore, when the core part 13 is a columnar body and the engagement hole H is a columnar space, the contact area between the core part 13 and the engagement hole H due to relative rotation is an elongated area extending in the axial direction. For this reason, compared with the case of a point contact, a wide contact area can be ensured and a further better electrical contact can be obtained. Even if the core portion 13 is not a columnar body as a whole or the engagement hole H is not a columnar space as a whole, a part of the axial direction facing each other at the time of overdriving is a columnar body and a columnar space. In this case, a contact region extending in the axial direction is obtained in the part, and better electrical contact can be obtained compared to the case of point contact.

  6 and 7 are explanatory views schematically showing an example of a method for manufacturing the contact probe 1 of FIG. 2, showing a manufacturing process of the contact probe using a so-called MEMS (Micro Electro Mechanical Systems) technique. Yes. MEMS is a technique for manufacturing a fine three-dimensional structure using a photolithography technique and a sacrificial layer etching technique. The photolithography technique is a fine pattern processing technique using a photosensitive resist used in a semiconductor manufacturing process or the like. The sacrificial layer etching technique is a technique for forming a three-dimensional structure by forming a lower layer called a sacrificial layer, further forming a layer constituting the structure thereon, and then etching only the sacrificial layer. .

  FIG. 6 shows a process of forming metal layers 42 and 44 and sacrificial layers 43 and 45 on the substrate 40 on which the sacrificial layer 41 is formed. FIG. 7 also shows a step of forming metal layers 46 and 48 and a sacrificial layer 47 for forming an upper gap.

  For the sacrificial layers 41, 43, 45, and 47, a metal that can leave the contact probe 1 and selectively remove only the sacrificial layer, for example, copper (Cu) is used by etching.

  FIG. 6A shows a process of forming the metal layer 42 on the substrate 40 on which the sacrificial layer 41 is previously formed. The metal layer 42 is a conductive metal layer corresponding to a part of the needle tip portion 10 and the root portion 12 and the lower inclined beam portion 11 </ b> B constituting the spring portion 11. The tilted beam 11A is formed in a plane parallel to the substrate 40 so as to have a tilted shape when the upper surface of the substrate 40 is viewed in plan. For the metal layer 42 forming the inclined beam portion 11A, a metal having an appropriate rigidity, for example, a nickel (Ni) alloy or an alloy containing a platinum group metal is used.

  First, an insulating layer such as a photoresist is formed on the sacrificial layer 41, and the insulating layer is patterned by exposure and development, so that a part of the sacrificial layer 41 is selectively exposed. Thereafter, a metal layer 42 is formed by depositing a metal on the exposed sacrificial layer 41 using a known method such as electroplating. The remaining insulating layer is then removed.

  FIG. 6B shows a step of forming a sacrificial layer 43 in a region where the metal layer 42 was not formed in the step (a), and polishing the surface to scrape off excess metal. The sacrificial layer 43 is formed to planarize the upper surface of the substrate 40. It is formed by depositing copper (Cu) on the substrate 40 using a known method such as electroplating. Thereafter, the sacrificial layer 43 deposited on the metal layer 42 is removed by polishing the surface, and the height of the metal layer 42 and the sacrificial layer 43 becomes uniform.

  FIG. 6C shows a step of forming the metal layer 44 on the substrate 40 after polishing. The metal layer 44 is a conductive metal layer corresponding to the contact tip CT of the needle tip portion 10, is hard to form an insulating film such as an oxide film, and is a hard metal having excellent wear resistance, for example, a platinum group. An alloy containing a metal is used. The metal layer 44 is formed by the same method as that for the metal layer 42.

  FIG. 6D shows a step of forming a sacrificial layer 45 for providing a gap below the core portion 13 on the substrate 40 on which the metal layer 44 is formed. The sacrificial layer 45 is also formed by the same method as that for the metal layer 42.

  FIG. 7A shows a process in which a metal layer 46 is formed on the substrate 40 on which the sacrificial layer 45 is formed, and the surface is polished to remove excess metal. The metal layer 46 is a conductive metal layer corresponding to the core portion 13, and a metal having a low resistivity and excellent slidability, for example, gold (Au) is used. The metal layer 46 is formed by the same method as that of the metal layer 42, and then the surface is polished.

  FIG. 7B shows a step of forming the sacrificial layer 47 on the substrate 40 on which the metal layer 46 is formed. The sacrificial layer 47 is formed in order to form gaps on both sides and the upper side of the core portion 13 and to form the engagement holes H. The sacrificial layer 47 is also formed by the same method as that for the metal layer 42.

  FIG. 7C shows a step of forming the metal layer 48 on the substrate 40 on which the sacrificial layer 47 is formed. The metal layer 48 is a conductive metal layer corresponding to the horizontal beam portions 11A and the upper inclined beam portions 11B on both sides constituting the spring portion 11, and the remaining portions of the needle tip portion 10 and the root portion 12. The same metal as layer 42, preferably the same metal material is used. Further, the metal layer 42 is formed by the same method.

  By forming the sacrificial layers 45 and 47 surrounding the core portion 13 (metal layer 46) and then laminating the metal layer 48, the horizontal beam portion 11A on both sides, the upper inclined beam portion 11B, the needle tip portion 10 and The remaining portion of the root portion 12 is formed by a single plating process in which the metal layer 48 is laminated. For this reason, a manufacturing process can be simplified.

  If the sacrificial layers 41, 43, 45 and 47 are removed from the substrate 40 after forming the metal layer 48, the needle tip portion 10 and the root portion 12 are connected by the spring portion 11, and one end is fixed to the needle tip portion 10. Then, the contact probe 1 having the core portion 13 whose other end is disposed in the engagement hole H of the root portion 12 so as to freely advance and retract is completed. In addition, it is desirable to improve the attachment property when the contact probe 1 is mounted on a wiring substrate such as the ST substrate 2 by covering the surface of the root portion 12 with gold or solder.

  FIG. 8 is a cross-sectional view showing another configuration example of the contact probe 1, and shows a case where the core portion 13 has a cross-sectional shape different from the engagement hole H of the root portion 12. In any case of (a) and (b), the diameter 13d of the minimum outer circle 13c of the core portion 13 is larger than the diameter Hd of the maximum inner circle Hc of the engagement hole H. For this reason, if the core part 13 and the engagement hole H rotate relatively, the core part 13 and the engagement hole H interfere with each other.

  (A) in the drawing shows a case where the core portion 13 has a concave cross section. More specifically, an example is shown in which the cross section of the core portion 13 has a substantially U-shape in which a rectangular concave portion is formed on a part of the long side of the rectangle. In the case of this contact probe 1, the cross section of the engagement hole H is rectangular, whereas the cross section of the core portion 13 has a polygonal shape whose diagonal is longer than the short side of the cross section of the engagement hole H. For this reason, at the time of overdrive, if the core part 13 and the engagement hole H rotate relatively beyond a certain angle due to the rotational stress of the spring part 11, the core part 13 and the engagement hole H interfere with each other.

  (B) in the figure shows a case where the core 13 has a convex cross section. More specifically, an example is shown in which the cross section of the core portion 13 has a shape in which a rectangular protrusion is added to a part of the long side of the rectangle. In the case of this contact probe 1, the cross section of the engagement hole H is rectangular, whereas the cross section of the core portion 13 is short in the cross section of the engagement hole H because the linear distance between the two most distant points on the circumference thereof. It consists of a polygon longer than the side. For this reason, at the time of overdrive, if the core part 13 and the engagement hole H rotate relatively beyond a certain angle due to the rotational stress of the spring part 11, the core part 13 and the engagement hole H interfere with each other.

  FIG. 9 is a cross-sectional view showing still another configuration example of the contact probe 1. The diameter 13d of the minimum outer circle 13c of the core portion 13 is larger than the diameter Hd of the maximum inner circle Hc of the engagement hole H. For this reason, if the core part 13 and the engagement hole H rotate relatively, the core part 13 and the engagement hole H interfere with each other.

  Each of the core 13 and the engagement hole H shown in the figure has a substantially L-shaped cross section and a size that interferes with each other. For this reason, at the time of overdrive, if the core part 13 and the engagement hole H rotate relatively beyond a certain angle due to the rotational stress of the spring part 11, the core part 13 and the engagement hole H interfere with each other.

  According to the present embodiment, the core portion 13 and the engagement hole H of the root portion 12 have cross-sectional shapes that interfere with each other, so that the core portion 13 disposed in the spring portion 11 and the upper end of the core portion 13 are advanced and retracted. Good electrical contact can be obtained with the engagement hole H that is freely arranged. In particular, if the needle tip portion 10 is pressed against the object to be inspected, the spring portion 11 is compressed, so that good electrical contact can be obtained during overdrive. In addition, since the deformation of the contact probe 1 is limited in the expansion / contraction direction of the spring portion 11, the possibility of contact with an adjacent probe can be reduced.

  In the present embodiment, an example has been described in which the lower end of the core portion 13 is connected to the tip portion 10 and the upper end is movably disposed in the engagement hole H of the root portion 12. It is not limited only to such a configuration. For example, the upper end of the core portion 13 can be connected to the root portion 12, and the lower end of the core portion 13 can be configured to move forward and backward in an engagement hole formed in the needle tip portion 10.

  In the present embodiment, an example in which the cross section of the engagement hole H is substantially rectangular has been described. However, the present invention does not limit the cross sectional shape of the engagement hole H to this. For example, the cross section of the engagement hole H may be a polygonal shape such as a triangle or a pentagon. If the engagement hole H has a cross-sectional shape that interferes with the core portion 13 when the core portion 13 and the root portion 12 are relatively rotated, the contact property during overdrive can be ensured.

  In the present embodiment, an example in which the contact probe 1 is manufactured using the MEMS technology has been described. However, the present invention does not limit the manufacturing method of the contact probe 1 to only MEMS.

  6 illustrates the case where the contact chip CT (metal layer 44) is formed before the sacrificial layer 45 for the lower gap is formed, the present invention limits the method for manufacturing the contact probe 1 to this. is not. For example, if the surface of the sacrificial layer 45 is polished and planarized, the metal layer 44 may be formed after the sacrificial layer 45 is formed and then the surface of the sacrificial layer 45 is polished. .

1 Contact probe 10 Needle tip part 11 Spring part 11A Horizontal beam part 11B Inclined beam part 12 Root part 13 Core part 13c Minimum outer circle diameter 13d Minimum outer circle diameter CT Contact tip H Engagement hole Hc Maximum inner circle Hd Maximum inner ring Circle diameter 2 ST substrate 3 Main substrate 4 Electrode pad 5 Semiconductor wafer 6 Movable stage 100 Probe card

Claims (3)

A spiral spring portion connecting the first end and the second end;
A core portion disposed in the spring portion, having one end connected to the first end portion, and the other end movably disposed in the engagement hole of the second end portion;
A contact probe characterized in that, in a cross section intersecting the longitudinal direction of the core part, a minimum diameter of a circle including the cross section of the core part is larger than a maximum diameter of a circle included in the cross section of the engagement hole. . The cross section of the engagement hole is substantially rectangular,
The contact probe according to claim 1, wherein a cross section of the core portion is formed of a polygon having a diagonal line longer than a short side of the cross section of the engagement hole.   3. The contact probe according to claim 1, wherein the core part and the engagement hole contact each other in an elongated region extending in a longitudinal direction of the core part by relatively rotating.

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