JP2019164152A - probe - Google Patents

Abstract

To provide a probe which ensures a desired stroke amount and needle pressure, and minimizes creeping and breakage of a needle even when a coil spring diameter is reduced.SOLUTION: A probe comprises a core material 3, and a coil spring 22 having one end thereof fixed or locked to the core material 3 and the other end fixed or locked to another member. The coil spring 22 is stiffer at the one end and the other end thereof than in a middle section 22b.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a probe, and more particularly to an improvement of a probe including a coil spring.

  The probe card is an inspection apparatus used to inspect the electrical characteristics of an electronic circuit formed on a semiconductor wafer, and is provided with a large number of fine probes that are brought into contact with electrodes on the electronic circuit. The characteristic inspection of the electronic circuit is performed by bringing the semiconductor wafer close to the probe card, bringing the tip of the probe into contact with the electrode on the electronic circuit, and conducting the tester device and the electronic circuit through the probe. At this time, in order to absorb variations in the height direction of the probe tip and the electrode, a process of bringing the semiconductor wafer closer to the probe card from a state where the probe tip and the electrode start to contact each other, so-called overdrive is performed.

  The spring probe is a vertical probe that can simultaneously ensure the stroke amount necessary for overdrive and the needle pressure necessary to obtain good contact performance. This type of spring probe includes an internal spring type in which a coil spring is accommodated in a cylinder, and an external spring type in which the coil spring is exposed. Since the outer spring type probe does not require a cylindrical body for accommodating the coil spring, it is more suitable for miniaturization than the inner spring type probe. However, in an external spring type probe in which a coil spring connects the needle tip and the needle base, the electrical resistance of the coil spring is large and the conduction performance is not good. In addition, the coil spring is curved during overdrive, and there is a problem that adjacent probes come into contact with each other.

  Therefore, an external spring type probe in which a core member is arranged coaxially with a spring member has been proposed (for example, Patent Document 1). The vertical coil spring probe A described in Patent Document 1 includes a contact pin 100A and a cylindrical body 200A that are arranged coaxially. The contact pin 100A includes a contact 110A that makes contact with an object to be measured and a guide 120A that extends in the axial direction. The cylindrical body 200A is a spring member that accommodates the guide element 120A, and the end on the needle tip side is fixed to the contact pin 100A. According to such an external spring type probe, since the current flows through the core material, the conduction performance is improved. Moreover, since the curvature of a spring member is restrict | limited when a core material contacts the internal peripheral surface of a spring member, the contact of adjacent probes can be prevented.

  An external spring type probe includes a contact pin 1 described in Patent Document 2. The contact pin 1 includes a main body portion 2 formed by winding a wire in a spiral shape, a reduced diameter portion 6 formed on one end portion side of the main body portion 2 and reducing in diameter toward one end, and the other of the main body portion 2. And a reduced diameter portion 10 that is formed on the end side and that decreases in diameter toward the other end. The contact pin 1 has no core material.

  Moreover, there is a spring contact assembly 10 described in Patent Document 3 as an outer spring type probe in which a core member is arranged coaxially with a spring member. The spring contact assembly 10 has a structure in which a plunger disposed coaxially with the spring 16 is separated into two plungers 12 and 14. One end of the spring 16 is fixed to the plunger 12 and the other end of the spring 16 is planned. It is fixed to the jar 14.

JP 2007-24664 A JP 2007-194187 A Special table 2010-539672 gazette

  Since the spring probe as described above can be two-dimensionally arranged in a narrow inspection region, the demand is increasing as electronic circuits are highly integrated. However, the conventional spring probe may cause problems such as broken needles due to fatigue associated with long-term use or multiple use. For example, when the diameter of the coil spring is reduced in accordance with the high integration of the electronic circuit while ensuring the desired stroke amount and needle pressure, the stress applied to the coil spring may increase, and creep or needle breakage may occur. there were.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a probe with improved reliability by suppressing the occurrence of defects. In particular, an object of the present invention is to provide a probe capable of suppressing the occurrence of creep and needle breakage even when the coil spring diameter is reduced while ensuring a desired stroke amount and needle pressure. .

  The probe according to the first aspect of the present invention includes a contact portion to be brought into contact with an object to be inspected, and a coil having one end fixed or locked to the contact portion and the other end fixed or locked to another member. And the coil spring is configured such that the rigidity of the one end and the other end is greater than the rigidity of the intermediate portion. The stress applied to the coil spring is maximized at both ends of the coil spring. For this reason, by making the rigidity of both end portions larger than that of the intermediate portion, the stress is dispersed, and the maximum stress can be reduced. Therefore, in this probe, even when the diameter of the coil spring is made thin while ensuring a desired stroke amount and needle pressure, the occurrence of creep and needle breakage can be suppressed.

  In the probe according to the second aspect of the present invention, in addition to the above configuration, the coil spring is formed of a linear body, and the cross-sectional area of the one end and the other end is larger than the cross-sectional area of the intermediate portion. Configured to be. According to such a structure, the rigidity of the both ends of a coil spring can be made larger than an intermediate part by varying the cross-sectional area of a linear body.

  In the probe according to a third aspect of the present invention, in addition to the above configuration, the coil spring is formed of a plate-like body having a uniform thickness in a direction intersecting the axial direction, and the shafts of the one end and the other end The width in the direction is configured to be wider than the intermediate portion. According to such a structure, the rigidity of the both ends of a coil spring can be made larger than an intermediate part by varying the width | variety of a plate-shaped object.

  In the probe according to a fourth aspect of the present invention, in addition to the above configuration, the coil spring is made of two or more metals, and the metal forming the one end and the metal forming the other end are the intermediate It is comprised so that an elasticity modulus may be larger than the metal which comprises a part. According to such a structure, the rigidity of the both ends of a coil spring can be made larger than an intermediate part by varying the elasticity modulus of the metal which comprises a coil spring.

  According to the present invention, it is possible to provide a probe capable of suppressing the occurrence of creep and needle breakage even when the diameter of a coil spring is reduced while ensuring a desired stroke amount and needle pressure. Can do. Therefore, it is possible to provide a probe with improved reliability by suppressing the occurrence of defects.

It is the perspective view which showed one structural example of the probe 1 by embodiment of this invention. It is sectional drawing which showed the structural example of the probe 1 of FIG. It is the figure which showed the operating characteristic of the probe 1, and the relationship between stylus pressure and stress is shown. It is the figure which showed the operating characteristic of the probe 1, and the relationship between the width W of the plate-shaped body 221 and a stress is shown. It is the figure which showed the structure in the principal part of the probe 1 of FIG. 1 compared with the comparative example. It is the figure which showed the operating characteristic of the probe 1 of FIG. 1 compared with the comparative example, and the relationship between the width W of the plate-shaped body 221 and stress is shown. It is the figure which showed the operating characteristic of the probe 1 of FIG. 1 compared with the comparative example, and the relationship between stroke amount and stress or needle pressure is shown. It is explanatory drawing which showed typically an example of the manufacturing method of the probe 1 of FIG. 1, and the operation | work process until the metal layer 44 which comprises the cylinder 2 is formed on the core material 40 is shown. FIG. 2 is an explanatory view schematically showing an example of a method for manufacturing the probe 1 of FIG. 1, and shows a work process until the sacrifice layer 42 is removed after the metal layer 44 is formed.

  Embodiments of the present invention will be described below with reference to the drawings. In the present specification, for convenience, the longitudinal direction of the probe is described as the vertical direction, but the posture of the probe according to the present invention is not limited.

<Probe 1>
FIG. 1 is a perspective view showing a configuration example of a probe 1 according to an embodiment of the present invention, and shows an external spring type spring probe. FIG. 2 is a cross-sectional view illustrating a configuration example of the probe 1 in FIG. 1, and shows a cut surface when the probe 1 is cut along an AA cutting line.

  The probe 1 is an external spring type spring probe that can be stroked in the vertical direction, and includes a cylindrical body 2 and a core member 3 that are arranged coaxially. The cylindrical body 2 is a member that holds the core material 3, and includes a needle tip portion 21, a coil spring 22, and a needle base portion 23. The coil spring 22 is a helical spring extending in the vertical direction, and biases the core material 3 downward by contracting in the axial direction.

  The needle tip portion 21 is a fixed portion that is fixed to the core member 3, and is provided at the lower end portion of the cylindrical body 2. When the needle tip portion 21 is cut along a horizontal plane, the cut surface has an annular shape. The needle base portion 23 is a cylindrical root portion that accommodates the upper end of the core member 3 so as to be movable in the axial direction, and is provided at the upper end portion of the cylindrical body 2. The needle base portion 23 is a cylindrical body that is fixed to a needle base side end portion 22c of a coil spring 22 to be described later and has the same inner diameter as the coil spring 22. For example, the needle base 23 is fixed to an electrode pad provided on a wiring board (not shown).

  The coil spring 22 is a connecting portion that connects the needle tip portion 21 and the needle base portion 23, and includes a plate-like body 221 that extends in a spiral shape. The plate-like body 221 has a shape extending along a three-dimensional curved string winding (helix), and one end is fixed to the needle tip portion 21 and the other end is fixed to the needle base portion 23. The thickness of the plate-like body 221 in the direction intersecting with the axial direction is uniform in the axial direction and the circumferential direction, and is substantially constant from the lower end to the upper end of the coil spring 22.

  On the other hand, the width W of the plate-like body 221 is wide at both ends of the coil spring 22. The width W is the length of the plate-like body 221 in the axial direction. If the coil spring 22 is divided into a needle tip side end portion 22a, an intermediate portion 22b, and a needle base side end portion 22c that are different from each other in the axial direction, the needle tip side end portion 22a and the needle base side end portion 22c are The width W of the plate-like body 221 is wider than that of the intermediate portion 22b.

  The needle tip side end portion 22 a is an end portion of the coil spring 22 on the needle tip portion 21 side. The needle base side end 22 c is an end of the coil spring 22 on the needle base 23 side. The intermediate portion 22b is a portion between the needle tip side end portion 22a and the needle base side end portion 22c. In this coil spring 22, the rigidity of both ends of the coil spring 22 is made larger than that of the intermediate portion 22b by making the width W of the plate-like body 221 different. The needle base side end portion 22 c is fixed to the electrode pad on the wiring board via the needle base portion 23. In addition, the structure which latches the needle | hook base side edge part 22c of the coil spring 22 to other members, such as a wiring board, may be sufficient.

  The pitch P of the plate-like body 221 is substantially constant from the lower end to the upper end of the coil spring 22. The pitch P is a repetition interval of the plate-like bodies 221 and is composed of an axial distance between the adjacent plate-like bodies 221.

  The core member 3 is a bar-like member extending in the vertical direction. The needle tip side end portion 22 a of the coil spring 22 is fixed via the needle tip portion 21 and is surrounded by the cylindrical body 2. In addition, the structure which latches the needle | hook tip side edge part 22a of the coil spring 22 to the core material 3 may be sufficient. For example, the needle tip side end portion 22a connected to the needle tip portion 21 is engaged with the core member 3 by engaging the needle tip portion 21 so as to be rotatable in the circumferential direction while restricting movement in the axial direction. May be locked to the core material 3.

  A lower end portion of the core material 3 protrudes from the needle tip portion 21 and forms a contact portion 31. The contact part 31 is a contact part for making it contact with a test object. When the core member 3 is cut along a horizontal plane, the cut surface is circular.

  The needle tip portion 21 is formed of a laminate in which a metal material is laminated on the outer peripheral surface of the core material 3, and the needle tip portion 21, the coil spring 22, the needle base portion 23, and the core material 3 are integrally formed. For this reason, since the work process for inserting the core material 3 into the coil spring 22 is not required, the probe 1 can be easily miniaturized. Moreover, since the work process for fixing the needle tip part 21 to the core material 3 is not necessary, the manufacturing cost can be reduced.

  If the material which comprises the probe 1 is illustrated concretely, the cylinder 2 will consist of metal materials, such as a nickel (Ni) alloy. A metal having higher elasticity than the core material 3 is used for the cylindrical body 2. The highly elastic metal here is a metal having a large elastic limit and a large elastic modulus such as Young's modulus.

  The core material 3 is made of a metal material or a conductive fiber material. Tungsten (W) or the like is used as the metal material. A CNT (carbon nanotube) fiber or the like is used as the conductive fiber material.

  For the core material 3, a conductive material having a hardness higher than that of the cylindrical body 2 is used. The high-hardness conductive material here is a hard conductive material that is difficult to be deformed and scratched. By using a conductive material having a high hardness, the wear resistance of the core material 3 can be improved.

  3 and 4 are diagrams showing the operating characteristics of the probe 1. These drawings show the experimental results of simulating the movement of the probe 1 using a computer and analyzing the stress applied to the probe 1. In this simulation, the outer diameter φ1 is 40 μm, the inner diameter φ2 is 30 μm, the axial length L1 of the needle tip 21 and the axial length L2 of the needle base 23 are both 100 μm, and the axial direction of the coil spring 22 A probe 1 having a length L of 1200 μm is used. Further, the width W and the pitch P of the plate-like body 221 are constant from the lower end to the upper end of the coil spring 22.

  The needle pressure applied to the inspection object by the probe 1 during overdrive is caused by an elastic force generated in the coil spring 22 when the coil spring 22 contracts in the axial direction due to a reaction force acting through the core member 3. By utilizing such elastic force, electrical connection between the probe 1 and the inspection object and electrical connection between the probe 1 and a wiring electrode provided on a wiring board (not shown). Connection is ensured.

  Since the load applied to the probe 1 at the time of overdrive is balanced with the elastic force of the coil spring 22, if the load applied to the probe 1 is analyzed, the width W and the pitch P of the plate-like body 221 are determined by the stroke amount and the stress. Alternatively, the influence on the relationship with the needle pressure can be determined.

  FIG. 3 shows the relationship between the needle pressure and the stress when the pitch P of the plate-like body 221 is changed and when the width W of the plate-like body 221 is changed. In this figure, the case where the stroke amount of the probe 1 is 100 μm is shown. The relationship between the stroke amount of the probe 1 and the needle pressure applied by the probe 1 varies greatly depending on the width W and pitch P of the plate-like body 221. On the other hand, the relationship between the stroke amount and the stress applied to the probe 1 is small when the width W is changed.

  Each of the characteristic curves VP1 to VP4 in the figure is a straight line indicating a proportional relationship between the needle pressure and the stress when the pitch P of the plate-like body 221 is changed, and the width W of the plate-like body 221 is different from each other. For example, the characteristic curve VP1 uses the probe 1 with W = 15 μm, the characteristic curve VP2 uses the probe 1 with W = 20 μm, the characteristic curve VP3 uses the probe 1 with W = 25 μm, and the characteristic curve VP4. Then, the probe 1 with W = 30 μm is used.

  It can be seen from these characteristic curves VP1 to VP4 that the needle pressure also decreases in proportion to the stress by narrowing the pitch of the plate-like body 221. It can also be seen that for the same stress, the needle pressure increases as the width W increases. On the other hand, with respect to the same needle pressure, it can be seen that the stress decreases as the width W increases.

  The characteristic curves VW1 to VW3 in the figure are all straight lines indicating the relationship between the needle pressure and the stress when the width W of the plate-like body 221 is changed, and the pitches P of the plate-like bodies 221 are different from each other. For example, the probe 1 with P = 30 μm is used in the characteristic curve VW1, the probe 1 with P = 50 μm is used in the characteristic curve VW2, and the probe 1 with P = 60 μm is used in the characteristic curve VW3.

  Looking at these characteristic curves VW1 to VW3, the amount of change in stress is small compared to the amount of change in needle pressure. Therefore, by increasing the width W of the plate-like body 221, an increase in stress is suppressed while the needle is being increased. It can be seen that the pressure can be increased. It can also be seen that the stress decreases with decreasing pitch P for the same needle pressure.

  FIG. 4 shows the relationship between the width W of the plate-like body 221 and the stress in the three probes 1 having different pitches P of the plate-like body 221. In this figure, the stress when the needle pressure is 1 gf is shown. Characteristic curves VW11 to VW13 in the figure are curves showing stress when the width W of the plate-like body 221 is changed, and the pitch P of the plate-like bodies 221 is different from each other.

  The characteristic curve VW11 uses the probe 1 with P = 30 μm, the characteristic curve VW12 uses the probe 1 with P = 50 μm, and the characteristic curve VW13 uses the probe 1 with P = 60 μm.

  From these characteristic curves VW11 to VW13, it can be seen that, at the same pitch P, the stress decreases as the width W of the plate-like body 221 increases. Further, it can be seen that, at the same width W, the stress decreases as the pitch P of the plate-like body 221 decreases. However, as the width W increases, the stress reduction effect due to the change in the pitch P decreases.

  FIG. 5 is a diagram showing the configuration of the main part of the probe 1 of FIG. 1 in comparison with a comparative example, in which the needle tip side end 22a of the coil spring 22 is shown. (A) in the figure shows the probe 1 according to the present invention, and (b) shows a comparative example. In the probe 1 according to the present embodiment, the width W of the plate-like body 221 is the other part of the coil spring 22, that is, the intermediate part 22b, at the needle tip side end 22a and the needle base side end 22c of the coil spring 22. Wider than.

  Specifically, the width W is wider than the intermediate portion 22b by one turn of the plate-like body 221 at the needle tip side end portion 22a. For example, W = 30 μm at the needle tip side end portion 22a, whereas W = 20 μm at the intermediate portion 22b. In addition, the width W of the plate-like body 221 is rapidly changed in a sufficiently narrow region as compared with the size of the step. The pitch P of the plate-like body 221 is P = 50 μm, and is constant from the lower end to the upper end of the coil spring 22. On the other hand, in the comparative example, W = 20 μm and P = 50 μm, and the width W and pitch P of the plate-like body 221 are constant from the lower end to the upper end of the coil spring 22.

  According to the computer simulation, it can be seen that the maximum stress applied to the probe 1 of the comparative example is generated locally at both ends of the coil spring 22. Therefore, in the present invention, the maximum stress is reduced by making the width W of the plate-like body 221 at both end portions of the coil spring 22 wider than other portions.

  According to the computer simulation, it is found that when the width W of the plate-like body 221 at both ends of the coil spring 22 is made wider than other portions, the stress is dispersed in the change region of the width W and the maximum stress is reduced. In the probe 1 according to the present embodiment, the width W of the plate-like body 221 at both end portions of the coil spring 22 is made wider than other portions, thereby suppressing the occurrence of creep and needle breakage.

  FIG. 6 is a diagram showing the operating characteristics of the probe 1 of FIG. 1 in comparison with the comparative example, and shows the relationship between the width W of the plate-like body 221 and the stress. In this figure, the stress when the needle pressure is 1 gf is shown. A characteristic curve VW in the figure is a curve showing the operating characteristics of the probe 1 according to the present invention. In this probe 1, only at both ends of the coil spring 22, the width W of the plate-like body 221 is fixed at W = 30 μm, and the width W of the intermediate portion 22b is changed in the range of 15 μm to 25 μm.

  On the other hand, the characteristic curve VW12 is a curve showing the operating characteristics of the comparative example. The pitch P of the plate-like body 221 is common to the probe 1 according to the present invention and the comparative example. When the characteristic curve VW is compared with the characteristic curve VW12, it can be seen that the stress is reduced by increasing the width W of the plate-like body 221 at both ends of the coil spring 22. That is, in the range where the width W is 15 μm or more and 25 μm or less, the stress is reduced in the probe 1 according to the present invention as compared with the comparative example.

  FIG. 7 is a diagram showing the operating characteristics of the probe 1 of FIG. 1 in comparison with a comparative example. The operating characteristics when the width W of the plate-like body 221 is W = 25 μm and the pitch P is P = 50 μm are shown. It is shown. (A) in the drawing shows the relationship between the stroke amount of the probe 1 and the stress, and (b) shows the relationship between the stroke amount of the probe 1 and the needle pressure.

  In the probe 1 according to the present invention, the width W of the plate-like body 221 is set to W = 30 μm and the width W of the intermediate portion 22 b is set to 25 μm only at both ends of the coil spring 22. In the comparative example, the width W of the plate-like body 221 is W = 25 μm from the lower end to the upper end of the coil spring 22.

  When the length L and the thickness of the coil spring 22 are fixed, the needle pressure and the stress with respect to the stroke amount are defined by the width W and the pitch P of the plate-like body 221. In addition, since the stress is defined by the elastic region of the coil spring 22, the conventional spring probe has a problem that the stroke amount is limited and sufficient needle pressure cannot be obtained.

  On the other hand, in the probe 1 according to the present embodiment, as can be seen from the illustrated characteristic curve, the change in the needle pressure is small and the stress is remarkably reduced. For example, when the stroke amount is 100 μm, the change amount Δb of the needle pressure is Δb = 0.05 gf, whereas the change amount Δa of the stress is Δa = 500 MPa. For this reason, it can be seen that by expanding the width W of the plate-like body 221 at both ends of the coil spring 22, the movable range of the coil spring 22 is expanded and sufficient needle pressure is obtained.

<Manufacturing process of probe 1>
8 and 9 are explanatory views schematically showing an example of a method for manufacturing the probe 1. Here, an example in which two or more probes 1 are manufactured simultaneously using a common core member 40 will be described. Each probe 1 is arranged with a different axial position. However, this embodiment is an example when the probe 1 is manufactured by a continuous processing process, and when only the coil spring 22 is manufactured, a part of them can be used. Further, the coil spring 22 can be manufactured by a method of pulling out the core portion as conventionally used.

  8A to 8F show work steps until the metal layer 44 constituting the cylindrical body 2 is formed on the core member 40. FIG. 9A and 9B show a work process until the sacrificial layer 42 is removed after the metal layer 44 is formed. 8 and 9 show a cut surface when each member is cut along a plane including the central axis of the core member 40. FIG.

  The probe 1 is manufactured using so-called MEMS (Micro Electro Mechanical Systems) technology. MEMS is a technique for producing 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. .

  In the probe 1, the cylindrical body 2 is integrally formed with the core material 40 by depositing a metal material on the core material 40 by electroplating and growing a plating layer on the outer side in the radial direction. If it demonstrates concretely, referring FIG.8 and FIG.9, the core material 40 extended linearly will be prepared as a base material first (FIG.8 (a)). The core material 40 is made of tungsten, CNT fiber, platinum-rhodium alloy, or rhenium-tungsten alloy.

  Next, a photoresist is applied on the core material 40 to form a resist layer 41, which is exposed through a photomask, and then developed to remove excess photoresist. The exposure process is performed by moving the light source for exposure in the circumferential direction. By patterning the resist layer 41, a non-formation region of the resist layer 41 is formed at an axial position corresponding to the coil spring 22 and the needle base 23 ((b) of FIG. 8).

  Next, a sacrificial layer 42 is formed as a base for plating in a region where the resist layer 41 is not formed by plating on the core material 40 after patterning the resist layer 41 (FIG. 8C). In this work process, the outer peripheral surface of the core member 40 facing the needle tip portion 21 is exposed, and the sacrifice layer 42 is formed by plating on the outer peripheral surface of the core member 40 facing the coil spring 22 and the needle base portion 23. It is a layer formation step.

  The sacrificial layer 42 is made of a metal that can be easily removed by an etchant, for example, copper (Cu). The resist layer 41 is removed using a release agent after the sacrificial layer 42 is formed ((d) in FIG. 8). By removing the resist layer 41, the core material 40 is exposed from the sacrificial layer 42 at an axial position corresponding to the contact portion 31 and the needle tip portion 21 of the core material 40.

  After removing the resist layer 41, a photoresist is applied on the core material 40 to form a resist layer 43. After exposure through a photomask, development processing is performed to remove excess photoresist. In the photomask in this step, an opening is formed so that the width W of the plate-like body 221 is wide at both ends of the coil spring 22. The exposure process other than the coil spring 22 is performed by moving the exposure light source in the circumferential direction. On the other hand, the exposure process of the coil spring 22 is performed by moving the core member 40 in the axial direction while moving the exposure light source in the circumferential direction. By patterning the resist layer 43, a non-formation region of the resist layer 43 is formed at an axial position corresponding to the needle tip portion 21, the coil spring 22, and the needle base portion 23 ((e) of FIG. 8). In particular, the non-formation region of the resist layer 43 formed at a position corresponding to the coil spring 22 is a spiral region surrounding the core member 40 and is wide at positions corresponding to both ends of the coil spring 22. .

  Next, the metal layer 44 constituting the cylindrical body 2 is formed in the non-formation region of the resist layer 43 by plating on the core material 40 after patterning the resist layer 43 ((f) in FIG. 8). . This work process is a cylinder forming step for forming the cylinder 2 by plating after the formation of the sacrificial layer 42. For example, a nickel alloy is used for the metal layer 44.

  The cylindrical body 2 is formed by selectively etching the metal layer 44 instead of the above manufacturing method of forming the cylindrical body 2 by forming the metal layer 44 using the resist layer 43 as a mask. Such a configuration may be adopted.

  Next, after the formation of the metal layer 44, the resist layer 43 is removed using a release agent ((a) of FIG. 9). If the sacrificial layer 42 is removed from the laminate by immersing the core material 40 after removing the resist layer 43 in the etchant for a predetermined time and infiltrating the etchant into the laminate of metal layers, the contact portion 31, the needle The tip portion 21, the coil spring 22, and the needle base portion 23 are completed ((b) of FIG. 9). This work process is a sacrificial layer removal step in which the sacrificial layer 42 is removed after the formation of the cylindrical body 2. For example, copper sulfate is used as the etching solution.

  Next, after removing the sacrificial layer 42, the probe 1 is separated into a single piece by cutting the core member 40 at a predetermined position. This work process is a probe separation step of separating the two or more probes 1 formed by cutting the core member 40 after forming the cylindrical body 2 and changing the axial position on the core member 40.

  By separating the probes 1, two or more probes 1 are simultaneously manufactured on the common core member 40, so that the number of work steps when manufacturing a plurality of probes 1 can be reduced. The core material 40 is cut by irradiating a laser beam to locally heat and melt the core material 40. Alternatively, the core material 40 is cut by cutting the core material 40 using a dicing saw.

  Next, after separating the probe 1, if the coil spring 22 is contracted in the axial direction by moving the needle base 23 toward the needle tip 21, a part of the core member 40 protrudes from the needle base 23. To do. By removing the core material 40 protruding from the end surface of the needle base portion 23 by contracting the coil spring 22, the core material 40 having the contact portion 31, the needle tip portion 21, the coil spring 22, and the needle base portion 23 are removed. The probe 1 constituted by the above is completed. This work process is a core material removal step of removing the core material 40 projected from the cylinder body 2 on the side opposite to the needle tip portion 21 by contracting the cylinder body 2 after the sacrifice layer 42 is removed.

  The removal of the core material 40 is performed by cutting the core material 40 at a predetermined position. This cutting process is performed by irradiating a laser beam to locally heat and melt the core material 40. Alternatively, the cutting process is performed by cutting the core material 40 using a dicing saw. By removing a part of the core member 40, the core member 40 is retracted from the needle base portion 23 side of the cylindrical body 2 to the needle tip portion 21 side when the coil spring 22 is in a natural length state. Even when the portion 23 is in contact with the electrode provided on the wiring board, the core member 40 can be stroked toward the wiring board while the coil spring 22 is contracted.

  According to the present embodiment, since the maximum stress applied to the coil spring 22 is reduced, the occurrence of creep or needle breakage can be suppressed. Moreover, since the rigidity of the both ends of the coil spring 22 is made larger than that of the intermediate portion 22b by making the width W of the plate-like body 221 different, the manufacture of the probe 1 can be facilitated. For example, since the width W of the plate-like body 221 can be varied by patterning when the metal layer 44 is laminated, the manufacture is easier than when the thickness of the plate-like body 221 is varied.

  Further, since the inner diameter of the needle base portion 23 is the same as that of the coil spring 22, the core material 3 is smoothly guided into the needle base portion 23 when the coil spring 1 is compressed. It is possible to prevent the needle base portion 23 from interfering.

  In the present embodiment, an example in which the coil spring 22 is composed of the plate-like body 221 has been described. However, the present invention does not limit the configuration of the coil spring 22. For example, the coil spring 22 is formed of a linear body extending in a spiral shape, and the cross-sectional area of the linear body at the needle tip side end 22a and the needle base side end 22c of the coil spring 22 is larger than the cross-sectional area of the intermediate portion 22b. Is also big. Thus, by making the cross-sectional areas of the linear bodies different, the rigidity of both end portions of the coil spring 22 can be made larger than that of the intermediate portion 22b.

  In the present embodiment, an example in which the coil spring 22 is made of one type of metal has been described. However, the present invention can also be applied to a case where the coil spring 22 is made of two or more types of metals. For example, the metal constituting the needle tip side end 22a and the metal constituting the needle base side end 22c have a larger elastic modulus than the metal constituting the intermediate portion 22b. Thus, by making the elasticity modulus of the metal which comprises the coil spring 22 different, the rigidity of the both ends of the coil spring 22 can be made larger than the intermediate part 22b.

  In the present embodiment, an example in which the width W of the plate-like body 221 changes rapidly has been described, but the configuration of the coil spring 22 is not limited to this. From the viewpoint of dispersing the stress, the plate-like body 221 preferably has a shape in which the axial width W continuously changes. For example, by changing the width W of the plate-like body 221 stepwise by two or more steps or along a smooth curve, the width W gradually increases from the end of the coil spring 22 toward the center. The configuration may be narrower. By configuring in this way, it is possible to prevent the maximum stress from being localized in the change region of the width W.

  In the present embodiment, the example in which the pitch P of the plate-like body 221 is substantially constant from the lower end to the upper end of the coil spring 22 has been described. However, the present invention limits the configuration of the coil spring 22 to this. It is not a thing. For example, the needle tip side end portion 22a and the needle base side end portion 22c of the coil spring 22 have a width W of the plate-like body 221 wider than the intermediate portion 22b, and a pitch P of the plate-like body 221 is larger than that of the intermediate portion 22b. Further, the maximum stress applied to the coil spring 22 can be further reduced by configuring the coil spring 22 to be narrow.

  Moreover, in this Embodiment, the example in case the cylinder 2 was comprised by the needle tip part 21, the coil spring 22, and the needle base part 23 was demonstrated. However, the present invention can also be applied to a probe in which the cylindrical body 2 does not include the needle tip portion 21 or the needle base portion 23. For example, even if the cylindrical body 2 is a probe composed only of the coil spring 22, it is possible to suppress problems such as broken needles by increasing the width W of the plate-like body 221 at both ends of the coil spring 22. can do.

DESCRIPTION OF SYMBOLS 1 Probe 2 Tubular body 21 Needle tip part 22 Coil spring 22a Needle tip side end part 22b Intermediate part 22c Needle side end part 23 Needle part 3 Core material 31 Contact part P Pitch W Width

Claims (4)

A contact portion to contact the inspection object;
A coil spring having one end fixed or locked to the contact portion and the other end fixed or locked to another member;
The coil spring is formed of a linear body, the cross-sectional area of the one end and the other end is larger than the cross-sectional area of the intermediate part, and the rigidity of the one end and the other end is A probe characterized by being larger than the rigidity of the intermediate portion. A contact portion to contact the inspection object;
A coil spring having one end fixed or locked to the contact portion and the other end fixed or locked to another member;
The coil spring is made of two or more kinds of metals, and the metal constituting the one end and the metal constituting the other end have a larger elastic modulus than the metal constituting the intermediate portion, The probe characterized by the rigidity of an edge part and said other edge part being larger than the rigidity of the said intermediate part.   The probe according to claim 2, wherein the coil spring is formed of a linear body, and a cross-sectional area of the one end portion and the other end portion is larger than a cross-sectional area of the intermediate portion.   The coil spring is made of a plate-like body having a uniform thickness in a direction intersecting the axial direction, and the axial width of the one end and the other end is wider than the intermediate portion. The probe according to claim 1 or 3.

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