JP6527762B2 - probe - Google Patents

Description

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

  The probe card is an inspection apparatus used to inspect the electrical characteristics of the electronic circuit formed on the semiconductor wafer, and is provided with a large number of fine probes to be in contact with the electrodes on the electronic circuit. The characteristic test 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 electrically connecting the tester apparatus and the electronic circuit through the probe. At that time, in order to absorb variations in the height direction of the tip of the probe and the electrodes, so-called overdrive processing is performed in which the semiconductor wafer is brought closer to the probe card from a state where the tip of the probe and the electrodes begin to contact.

  The spring probe is a vertical probe capable of simultaneously securing the stroke amount required for overdrive and the needle pressure required to obtain good contact performance. There exist an inner spring type thing which accommodates a coil spring in a cylinder body, and an external spring type thing which a coil spring exposes in this kind of spring probe. The outer spring type probe is more suitable for miniaturization than the inner spring type probe because it does not require a cylinder for accommodating the coil spring. However, in an external spring type probe in which a coil spring connects a needle tip and a needle base, the electrical resistance of the coil spring is large and the conduction performance is not good. In addition, there is also a problem that the coil spring is bent at the time of overdrive and the adjacent probes are in contact with each other.

  Therefore, an external spring type probe in which the core material is disposed coaxially with the 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 cylinder 200A coaxially arranged. The contact pin 100A includes a contact 110A for contacting an object to be measured, and an axially extending guide 120A. The cylindrical body 200A is a spring member that accommodates the guider 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. Further, since the curvature of the spring member is limited by the core material coming into contact with the inner circumferential surface of the spring member, contact between adjacent probes can be prevented.

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

  Further, as an external spring type probe in which a core material is disposed coaxially with a spring member, there is also a spring contact assembly 10 described in Patent Document 3. The spring contact assembly 10 has a structure in which a plunger coaxially arranged with the spring 16 is divided 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 a plan It is fixed to the jar 14.

Unexamined-Japanese-Patent No. 2007-24664 JP 2007-194187 A Japanese Patent Publication No. 2010-539672

  Since the spring probe as described above can be arranged two-dimensionally with respect to a narrow inspection area, the demand is expanding with the high integration of the electronic circuit. However, in the conventional spring probe, there is a possibility that a defect such as a broken needle may occur due to fatigue caused by long-term use or multiple use. For example, if the diameter of the coil spring is reduced according to the high integration of the electronic circuit while securing the desired stroke amount and needle pressure, the stress applied to the coil spring may increase, which may cause creep or needle breakage. there were.

  The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide a probe whose reliability is improved by suppressing the occurrence of a defect. In particular, it is an object of the present invention 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 securing a desired stroke amount and needle pressure. .

  The probe according to the first aspect of the present invention is a core material and a coil spring in which one end is fixed or locked to the core material in the axial direction and the other end is fixed or locked to another member. And the coil spring is configured such that the stiffness of the one end and the other end is greater than the stiffness of the middle. The stress applied to the coil spring is maximum at both ends of the coil spring. For this reason, stress can be dispersed and maximum stress can be reduced by making the rigidity of both end portions larger than that of the middle portion. Therefore, with this probe, it is possible to suppress the occurrence of creep and needle breakage even when the diameter of the coil spring is reduced while securing the desired stroke amount and needle pressure.

  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 middle Configured to be According to such a configuration, by making the cross-sectional area of the linear body different, the rigidity of both ends of the coil spring can be made larger than that of the middle part.

  In the probe according to the 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 an axis of the one end and the other end The width of the direction is configured to be wider than the middle portion. According to such a configuration, the rigidity of both ends of the coil spring can be made larger than that of the middle portion by making the widths of the plate-like members different.

  In the probe according to the 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 middle The elastic modulus is configured to be larger than that of the metal constituting the part. According to such a configuration, the rigidity of both end portions of the coil spring can be made larger than that of the middle portion by making the elastic modulus of the metal constituting the coil spring different.

  In addition to the above configuration, the probe according to the fifth aspect of the present invention includes a cylindrical body fixed to the other end and having an inner diameter equal to that of the coil spring. According to such a configuration, when the coil spring is compressed, the core material is smoothly guided into the cylindrical body, so that interference between the core material and the cylindrical body can be prevented.

  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 securing a desired stroke amount and needle pressure. Can. Therefore, a probe with improved reliability can be provided by suppressing the occurrence of a defect.

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 a figure showing the operation characteristic of probe 1, and the relation between needle pressure and stress is shown. It is a figure showing the operation characteristic of probe 1, and the relation between width W of plate-like object 221, and stress is shown. It is the figure which showed the structure in the principal part of the probe 1 of FIG. 1 in comparison with a comparative example. It is the figure which showed the operating characteristic of the probe 1 of FIG. 1 in comparison with a comparative example, and the relationship between the width W of the plate-like body 221 and stress is shown. It is the figure which showed the operation | movement characteristic of the probe 1 of FIG. 1 in comparison with a comparative example, and the relationship between stroke amount and stress or needle pressure is shown. FIG. 10 is an explanatory view schematically showing an example of a method of manufacturing the probe 1 of FIG. 1, and shows a working process until the metal layer 44 constituting the cylinder 2 is formed on the core material 40. FIG. FIG. 16 is an explanatory view schematically showing an example of a method of manufacturing the probe 1 of FIG. 1, showing a working process until the sacrificial layer 42 is removed after the formation of the metal layer 44.

  Hereinafter, embodiments of the present invention will be described 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 in use of the probe according to the present invention is not limited.

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

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

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

  The coil spring 22 is a connecting portion that connects the needle tip portion 21 and the needle base portion 23 and is formed of a plate-like body 221 extending in a spiral shape. The plate-like body 221 has a shape extending along a three-dimensional curved wire winding (helix), one end thereof is fixed to the needle tip portion 21 and the other end is fixed to the needle root portion 23. The thickness in the direction intersecting with the axial direction of the plate-like body 221 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. When the coil spring 22 is divided into the needle tip side end 22a, the intermediate portion 22b, and the needle origin side end 22c whose axial positions are different from each other, the needle tip side end 22a and the needle origin end 22c are The width W of the plate-like body 221 is wider than the middle portion 22 b.

  The needle tip end 22 a is an end of the coil spring 22 on the needle tip 21 side. The needle base end 22 c is an end of the coil spring 22 on the needle base 23 side. The middle portion 22 b is a portion between the needle tip side end 22 a and the needle base side end 22 c. In the coil spring 22, the rigidity of both ends of the coil spring 22 is made larger than that of the middle portion 22 b by making the width W of the plate-like body 221 different. The needle base end 22 c is fixed to the electrode pad on the wiring substrate via the needle base 23. The needle source side end 22c of the coil spring 22 may be locked to another member such as a wiring board.

  Moreover, 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 members 221 and is an axial distance between the plate-like members 221 adjacent to each other.

  The core member 3 is a rod-like member extending in the vertical direction, and the needle tip end 22 a of the coil spring 22 is fixed via the needle tip 21 and is surrounded by the cylinder 2. The needle tip end 22 a of the coil spring 22 may be engaged with the core 3. For example, the needle tip side end 22 a connected to the needle tip 21 by engaging the needle tip 21 rotatably in the circumferential direction while restricting the axial movement of the core material 3. May be locked to the core 3.

  The lower end portion of the core material 3 protrudes from the needle tip portion 21 to form a contact portion 31. The contact portion 31 is a contact portion for contacting an inspection object. The cut surface when the core material 3 is cut by a horizontal surface is circular.

  The needle tip portion 21 is a laminated body 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 operation | work process for inserting the core material 3 in the coiled spring 22 is unnecessary, refinement | miniaturization of the probe 1 is easy. In addition, since the operation process for fixing the needle tip portion 21 to the core member 3 is also unnecessary, 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. For the cylindrical body 2, a metal having a higher elasticity than the core material 3 is used. The metal of high elasticity referred to here is a metal having a large elastic limit and a large elastic modulus such as Young's modulus.

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

  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 referred to here is a hard conductive material which is hard to deform and hard to be scratched. By using a conductive material having high hardness, the wear resistance of the core 3 can be improved.

  3 and 4 are diagrams showing the operating characteristics of the probe 1. These figures show the results of experiments in which the movement of the probe 1 was simulated using a computer and the stress applied to the probe 1 was analyzed. In this simulation, the outer diameter φ1 is 40 μm, the inner diameter φ2 is 30 μm, the axial length L1 of the 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 The probe 1 having a length L of 1200 μm is used. Further, the width W and the pitch P of the plate-like member 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 at the time of overdrive is due to the elastic force generated on the coil spring 22 when the coil spring 22 is contracted in the axial direction by the reaction force acting through the core material 3. By utilizing such elastic force, the electrical connection between the probe 1 and the inspection object, and the electrical connection between the probe 1 and the wiring electrode provided on the wiring substrate (not shown) Connection is secured.

  The load applied to the probe 1 at the time of overdrive is balanced with the elastic force of the coil spring 22. Therefore, if the load applied to the probe 1 is analyzed, the width W and the pitch P of the plate-like body 221 are stroke amount and 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 largely varies depending on the width W and the 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 has a small variation when the width W is changed.

  The characteristic curves VP1 to VP4 in the figure are all straight lines showing the 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, in the characteristic curve VP1, the probe 1 of W = 15 μm is used, in the characteristic curve VP2, the probe 1 of W = 20 μm is used, and in the characteristic curve VP3, the probe 1 of W = 25 μm is used, the characteristic curve VP4 In, the probe 1 of W = 30 μm is used.

  From these characteristic curves VP1 to VP4, it can be seen that the needle pressure is also reduced in proportion to the stress by narrowing the plate-like member 221. In addition, it can be seen that the needle pressure increases as the width W increases for the same stress. On the other hand, it can be seen that the stress decreases as the width W increases for the same needle pressure.

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

  As seen from these characteristic curves VW1 to VW3, the amount of change in stress is smaller than the amount of change in needle pressure. Therefore, by increasing the width W of the plate-like body 221, the needle is suppressed while suppressing an increase in stress. It can be seen that the pressure can be increased. In addition, it is understood that the stress decreases as the pitch P is narrowed for the same needle pressure.

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

  In the characteristic curve VW11, the probe 1 of P = 30 μm is used, in the characteristic curve VW12, the probe 1 of P = 50 μm is used, and in the characteristic curve VW13, the probe 1 of P = 60 μm is used.

  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 becomes wider. Further, it can be seen that with the same width W, the stress decreases as the pitch P of the plate-like members 221 becomes narrower. However, if the width W becomes wider, the reduction effect of the stress due to the change of the pitch P becomes smaller.

  FIG. 5 is a view 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 end 22 a of the coil spring 22 is shown. A probe 1 according to the present invention is shown in (a) in the figure, and a comparative example is shown in (b). In the probe 1 according to the present embodiment, the width W of the plate member 221 is the other portion of the coil spring 22 at the needle tip end 22a and the needle end 22c of the coil spring 22, that is, the middle portion 22b. It is wider than.

  Specifically, the width W is wider than the middle portion 22 b by one turn of the plate-like body 221 at the needle tip side end 22 a. For example, while W = 30 μm at the needle tip end 22a, W = 20 μm at the intermediate portion 22b. In addition, the width W of the plate-like body 221 rapidly changes in a sufficiently narrow region compared to the size of the step. The pitch P of the plate-like members 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, P = 50 μm, and 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.

  According to computer simulation, it is understood 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 the other portions.

  According to computer simulation, when the width W of the plate-like body 221 at both ends of the coil spring 22 is made wider than the other portions, it is understood that 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, occurrence of creep and needle breakage is suppressed by making the width W of the plate-like body 221 at both end portions of the coil spring 22 wider than the other portions.

  FIG. 6 is a diagram showing the operating characteristics of the probe 1 of FIG. 1 in comparison with a comparative example, and shows the relationship between the width W of the plate-like body 221 and the stress. In this figure, the stress is shown when the needle pressure is 1 gf. The characteristic curve VW in the figure is a curve showing the operating characteristic of the probe 1 according to the present invention. In this probe 1, the width W of the plate-like body 221 is fixed at W = 30 μm only at both end portions of the coil spring 22, 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 characteristic 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. If 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 of the width W of 15 μm or more and 25 μm or less, the stress of the probe 1 according to the present invention is reduced 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 the comparative example, and 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 It is shown. The relationship between the stroke amount of the probe 1 and the stress is shown in (a) of the figure, and the relationship between the stroke amount of the probe 1 and the needle pressure is shown in (b).

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

  When the length L and thickness of the coil spring 22 are fixed, the needle pressure and stress for the stroke amount are defined by the width W and the pitch P of the plate-like body 221. Further, 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 a sufficient needle pressure can not 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 needle pressure is small and the stress is significantly reduced. For example, when the stroke amount is 100 μm, the change amount Δb of needle pressure is Δb = 0.05 gf, whereas the change amount Δa of stress is Δa = 500 MPa. For this reason, it is understood that the movable range of the coil spring 22 is expanded by enlarging the width W of the plate-like body 221 at both end portions of the coil spring 22, and a sufficient needle pressure can be obtained.

<Manufacturing process of probe 1>
8 and 9 are explanatory views schematically showing an example of a method of manufacturing the probe 1. Here, an example in the case where two or more probes 1 are simultaneously manufactured using the common core material 40 will be described. The respective probes 1 are arranged at different axial positions. However, this embodiment is an example of the case where the probe 1 is manufactured by the continuous processing process, and when only the coil spring 22 is manufactured, a part of this can be used. Further, it is also possible to manufacture the coil spring 22 by a method of pulling out the core portion as conventionally used.

  The work process until it forms the metal layer 44 which comprises the cylinder 2 on the core material 40 is shown by (a)-(f) of FIG. FIGS. 9A and 9B show the operation steps after the formation of the metal layer 44 until the sacrificial layer 42 is removed. FIGS. 8 and 9 show cut surfaces in the case where each member is cut by a plane including the central axis of the core material 40.

  The probe 1 is manufactured using so-called MEMS (Micro Electro Mechanical Systems) technology. MEMS is a technology for producing a fine three-dimensional structure using photolithography technology and sacrificial layer etching technology. The photolithography technology is a processing technology of a fine pattern using a photosensitive resist used in a semiconductor manufacturing process or the like. In addition, the sacrificial layer etching technique is a technique in which a lower layer called a sacrificial layer is formed, a layer constituting the structure is further formed thereon, and then only the sacrificial layer is etched to form a three-dimensional structure. .

  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 to FIG.8 and FIG.9, the core material 40 extended linearly may be prepared as a base material first ((a) of FIG. 8). The core member 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, and after exposure through a photomask, development is performed 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 axial positions corresponding to the coil spring 22 and the needle base portion 23 ((b) in FIG. 8).

  Next, a sacrificial layer 42 is formed as a base for plating in the non-formation region of the resist layer 41 by plating on the core material 40 after patterning the resist layer 41 ((c) in FIG. 8). In this work process, the outer peripheral surface of the core 40 facing the needle tip 21 is exposed, and the sacrificial layer 42 is formed by plating on the outer peripheral surface of the core 40 facing the coil spring 22 and the needle base 23. It is a layer formation step.

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

  After the resist layer 41 is removed, a photoresist is applied on the core material 40 to form a resist layer 43, and after exposure through a photomask, development 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 becomes wide at both ends of the coil spring 22. The exposure processing other than the coil spring 22 is performed by moving the light source for exposure in the circumferential direction. On the other hand, the exposure process of the coil spring 22 is performed by moving the core material 40 in the axial direction while moving the light source for exposure in the circumferential direction. By patterning the resist layer 43, a non-formation region of the resist layer 43 is formed at axial positions corresponding to the needle tip 21, the coil spring 22 and the needle base 23 ((e) in FIG. 8). In particular, the non-formation region of the resist layer 43 formed at the position corresponding to the coil spring 22 is a helical region surrounding the core material 40 and is wider at the position 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 operation step is a cylinder forming step of 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.

  It should be noted that the metal layer 44 is formed using the resist layer 43 as a mask, and instead of the above manufacturing method of forming the cylinder 2, the cylinder 2 is formed by selectively etching the metal layer 44. It may be of such a configuration.

  Next, after forming the metal layer 44, the resist layer 43 is removed using a release agent ((a) in FIG. 9). The core layer 40 after removing the resist layer 43 is immersed in an etching solution for a predetermined time, and the etching solution is infiltrated into the inside of the metal layer laminate to remove the sacrificial layer 42 from the laminate, the contact portion 31 and the needle The tip 21, the coil spring 22, and the needle base 23 are completed ((b) in FIG. 9). This operation step is a sacrificial layer removing step of removing the sacrificial layer 42 after the formation of the cylindrical body 2. For example, copper sulfate is used for the etching solution.

  Next, after the sacrificial layer 42 is removed, the core material 40 is cut at a predetermined position, whereby the probe 1 is separated into single components. This operation step is a probe separation step of cutting the core material 40 after the formation of the cylindrical body 2 and separating two or more probes 1 formed on the core material 40 with different axial positions.

  By separating the probes 1, two or more probes 1 are simultaneously produced on the common core material 40, so the number of operation steps when producing a plurality of probes 1 can be shortened. Cutting of the core material 40 is performed by locally heating and melting the core material 40 by irradiating laser light. Alternatively, cutting of the core material 40 is performed by cutting the core material 40 using a dicing saw.

  Next, after the probe 1 is separated, when the coil spring 22 is contracted in the axial direction by moving the needle base portion 23 to the needle tip portion 21 side, a part of the core material 40 protrudes from the needle base portion 23 Do. The core material 40 having the contact part 31, the needle tip part 21, the coil spring 22, and the needle base part 23 by removing the core material 40 which is made to project from the end face of the needle base part 23 by contracting the coil spring 22. And the probe 1 configured by is completed. This operation process is a core material removing step of removing the core material 40 which is made to project from the cylinder 2 on the side opposite to the needle point portion 21 by shrinking the cylinder 2 after the removal of the sacrificial layer 42.

  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 locally heating and melting the core material 40 by irradiating a laser beam. 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, when the coil spring 22 has a natural length, the core member 40 recedes to the needle tip 21 side with respect to the needle root portion 23 of the cylindrical body 2, the needle root Even in the state in which the portion 23 is in contact with the electrode provided on the wiring board, the core member 40 can be made to stroke toward the wiring board while contracting the coil spring 22.

  According to the present embodiment, since the maximum stress applied to the coil spring 22 is reduced, the occurrence of creep and needle breakage can be suppressed. Further, by making the width W of the plate-like body 221 different, the rigidity of both end portions of the coil spring 22 is made larger than that of the middle portion 22b, so that the manufacture of the probe 1 can be facilitated. For example, since the width W of the plate-like body 221 can be made different by patterning when laminating the metal layer 44, the manufacture is easier as compared with the case where the thickness of the plate-like body 221 is made different.

  Further, since the inner diameter of the needle base portion 23 is the same as that of the coil spring 22, when the coil spring 1 is compressed, the core material 3 is smoothly guided into the needle base portion 23. Interference of the needle base portion 23 can be prevented.

  In the present embodiment, an example in which the coil spring 22 is formed of the plate-like body 221 has been described, but the present invention does not limit the configuration of the coil spring 22 to this. For example, the coil spring 22 is formed of a helically extending linear body, 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 greater than that of the middle portion 22b. Too big. By making the cross-sectional area of the linear body different in this manner, the rigidity of both ends of the coil spring 22 can be made greater than that of the middle portion 22 b.

  Moreover, although the example in case the coiled spring 22 consists of 1 type of metal was demonstrated in this Embodiment, this invention is applicable also to what the coiled spring 22 consists of 2 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 middle portion 22b. By making the elastic modulus of the metal constituting the coil spring 22 different as described above, the rigidity of both ends of the coil spring 22 can be made greater than that of the intermediate portion 22 b.

  Moreover, although the example in the case where the width W of the plate-like body 221 changes rapidly is described in the present embodiment, the configuration of the coil spring 22 is not limited to this. From the viewpoint of dispersing stress, the plate-like body 221 desirably has a shape in which the axial width W continuously changes. For example, the width W gradually increases from the end of the coil spring 22 toward the central portion by changing the width W of the plate-like body 221 stepwise by two or more steps or by changing along a smooth curve. The configuration may be narrow. By configuring in this manner, it is possible to prevent the maximum stress from being localized in the change region of the width W.

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

  Further, in the present embodiment, an example in which the cylindrical body 2 is configured by the needle tip portion 21, the coil spring 22 and the needle base portion 23 has been described. However, the present invention can also be applied to a probe in which the cylindrical body 2 does not have the tip 21 or the tip 23. For example, even if the cylindrical body 2 is a probe constituted only by the coil spring 22, by making the width W of the plate-like body 221 wider at both ends of the coil spring 22, it is possible to suppress occurrence of defects such as needle breakage. can do.

DESCRIPTION OF SYMBOLS 1 probe 2 cylinder 21 needle tip 22 coil spring 22 a needle tip side end 22 b intermediate portion 22 c needle source side end 23 needle base 3 core 31 contact portion P pitch W width

Claims (5)

Core material,
And a coil spring having one end fixed or locked to the core and the other end fixed or locked to the other member in the axial direction.
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 middle part, and the rigidity of the one end and the other end is the above A probe characterized by being greater than the stiffness of the middle part. Core material,
And a coil spring having one end fixed or locked to the core and the other end fixed or locked to the other member in the axial direction.
The coil spring is made of two or more metals, and the metal forming the one end and the metal forming the other end have a larger elastic modulus than the metal forming the middle , probe rigidity of the end portion and the other end being greater than the stiffness of the intermediate portion. 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 and the other end is larger than a cross-sectional area of the middle part. The coil spring is formed of a plate-like member having a uniform thickness in a direction intersecting with the axial direction, and an axial width of the one end and the other end is wider than that of the middle part. The probe according to claim 1 or 3 , characterized by   The probe according to any one of claims 1 to 4, further comprising a cylindrical body fixed to the other end and having an inner diameter equal to that of the coil spring.

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