JP2008196905A - Contact probe, its using method, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive contact probe which is used in an inspection method for obtaining sufficient contact pressure with respect to an object to be measured to measure its electric characteristic by applying loads to both ends of the probe and bending it, facilitates setting for its probe unit, and enables accurate and stable contact to a lead wire and does not cause a defect such as imperfect contact. <P>SOLUTION: The contact probe has a trunk part A having an insulating coat 3 on the periphery of a metal conductor 2 in a pin shape, and edge parts B having no insulating coats 3 at both ends of the metal conductor 2, and obtains the contact pressure with respect to the object to be measured and measures the electric characteristic by applying the loads to both ends of the probe and bending it. One-side or both-side edge parts B of the contact probe 1 are in a semispherical shape, a needle-like shape, a conical shape, or a flat shape, and the trunk part A of the contact probe 1 is so structured as to have a concave stopper part(s) 4 where the thickness of the insulating coat 3 is partially smaller or where a part(s) of the insulating coat 3 is(are) removed at one site or more. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a contact probe for inspection mainly used for continuity inspection of electronic components and substrates, a method for using the same, and a method for manufacturing the same. More specifically, the present invention relates to a measured object by applying a weight to both ends. In an inspection method using a contact probe that measures electrical characteristics by obtaining a contact pressure, relates to a contact probe that is easy to set and reduces the possibility of occurrence of defects such as contact failure, a method for using the contact probe, and a method for manufacturing the contact probe It is.

  In recent years, various circuit boards such as high-density mounting boards used for mobile phones and the like, IC package boards such as BGA (Ball Grid Array) and CSP (Chip Size Package) incorporated in personal computers, etc., are often used. Yes. Such a circuit board is subjected to, for example, a measurement of a direct current resistance value or a continuity test in the processes before and after mounting, and the electrical characteristics of the circuit board are inspected. The inspection of electrical characteristics is performed using an inspection apparatus jig (hereinafter referred to as “probe unit”) connected to an inspection apparatus for measuring electrical characteristics. For example, a pin shape mounted on the probe unit is used. The probe (referred to as “contact probe” in this application) is brought into contact with the electrode (hereinafter also referred to as “measurement object”) of the circuit board (see, for example, Patent Document 1). .

  FIG. 6 is a schematic diagram (A) showing a state in which a conventional contact probe is set in a probe unit, and a schematic diagram (B) showing a state in which the measured object is inspected by bending the contact probe. . The contact probe 101 shown in FIG. 6 includes a body portion in which a linear metal conductor having spring properties is covered with an insulating film 103, and both end portions where the insulating film is peeled off and the metal conductor 102 is exposed. Has been. Both ends of the contact probe 101 are constituted by a tip end 102 a that contacts the electrode 112 of the measurement object 111 and a rear end 102 b that contacts the lead wire 150 on the inspection apparatus side. In such a contact probe 101, (1) after both ends of a metal conductor 102 cut to a predetermined length are ground into a predetermined shape, an insulating paint is spray-coated in a state where a predetermined region including both ends is masked. Manufactured or (2) A metal conductor with an insulating coating that is continuously baked and enameled on a long metal conductor is cut to a predetermined length, and an insulating coating in a predetermined region including both ends is laser-peeled or mechanically peeled off It is manufactured by grinding both ends after removing by.

  Further, the probe unit 110 shown in FIG. 6 includes a plurality of contact probes 101, a plate 130 with a guide hole for guiding the lead wire side of the contact probe 101, and the tip 102a of the contact probe 101. It includes at least a plate 120 with a guide hole for guiding the electrode side of the contact probe 101 so as to contact the electrode 112 of 111. The inspection of the electrical characteristics is performed by moving the probe unit 110 or the measured object 111 relatively up and down and pressing the contact probe 101 against the electrode 112 of the measured object 111 with a predetermined pressure using its elastic force. . At this time, the rear end 102b of the contact probe 101 bent by the force pressed against the electrode 112 strongly contacts the lead wire 150, and an electrical signal from the measured object 112 passes through the lead wire 150 and is inspected (shown). Not sent.) In FIG. 6, reference numeral 140 denotes a lead wire holding plate.

In such a probe unit 110, the guide hole provided in the plate 130 is formed with a diameter larger than the diameter of the contact probe 101 covered with the insulating film 103, while the guide hole provided in the plate 120 is formed with the insulating film. It is formed with a diameter smaller than the diameter of the contact probe 101 covered with 103 and larger than the diameter of the metal conductor 102. Therefore, the setting of the contact probe 101 to the probe unit 110 is performed by inserting the contact probe 101 from the guide hole provided in the plate 130. Then, the end surface 103a of the insulating coating 103 on the front end side is caught by the plate 120, thereby preventing the contact probe 101 from falling.
JP 2002-131334 A

  However, as shown in FIGS. 6A and 6B, the conventional contact probe 101 has a large clearance between the guide hole of the plate 130 on the lead wire side and the rear end 102b of the contact probe 101 on the lead wire side. However, the centering of the rear end 102b is not performed sufficiently, and the contact position between the rear end 102b and the lead wire 150 is unstable and uncertain.

  Further, since the setting of the contact probe 101 to the probe unit 110 has only to be inserted from the plate 130 on the lead wire side, at the time of insertion, the probe unit 110 must be disassembled and removed from the inspection apparatus, and the setting is complicated. There was a problem of becoming.

  In addition, since the contact between the rear end 102b of the contact probe 101 and the lead wire 150 is repeated for each measurement, there is a problem that the oxide powder generated by the contact causes a contact failure.

  Further, the conventional contact probe is manufactured by a method with a large number of processing steps, which causes an increase in cost. Specifically, in a manufacturing method in which an insulating paint is spray-coated after masking on a metal conductor of a predetermined length, it is manufactured through at least cutting, grinding, masking, and coating, while a metal with a long insulating coating is used. In the method of peeling off the insulating film at both ends after cutting the conductor, it is manufactured through at least enamel baking, cutting, peeling, and grinding, and all the manufacturing methods have a large number of processing steps, which causes a cost increase. .

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an inspection method for measuring electrical characteristics by obtaining a contact pressure with respect to an object to be measured by applying a weight to both ends to bend. It is an object of the present invention to provide a low-cost contact probe that can be easily set to a probe unit and that can be brought into contact with a lead wire accurately and stably and that does not cause problems such as poor contact. Another object of the present invention is to provide a method for using such a contact probe and a method for manufacturing the contact probe at a low cost.

  The contact probe of the present invention for solving the above-mentioned problems has a body portion having an insulating coating on the outer periphery of a pin-shaped metal conductor, and end portions having no insulating coating on both ends of the metal conductor, In the contact probe of a method for measuring the electrical characteristics by obtaining the contact pressure against the object to be measured by applying a weight to the contact probe, one or both sides of the end portion of the contact probe are hemispherical, needle-shaped, conical-shaped Alternatively, the body portion of the contact probe has one or more concave stopper portions where the thickness of a portion of the insulating coating is thin or a concave stopper portion where a portion of the insulating coating is removed. It is characterized by.

  According to the present invention, (1) the body portion of the contact probe has one or more concave stopper portions in which a portion of the insulating coating is thin or a concave stopper portion from which a portion of the insulating coating is removed. If the stopper portion is fixed with, for example, a positioning plate for the probe unit, the contact probe can be easily and accurately fixed in the probe unit. As a result, the centering of the end portion of the metal conductor is sufficient, and the lead wire can be brought into contact with the lead wire accurately and stably. (2) If the contact probe can be fixed in the probe unit as described above, the rear end of the contact probe and the lead wire are always in contact with each other, and the tip end side of the contact probe is bent to be covered. Since it can be brought into contact with the measurement body, generation of oxide powder due to repeated contact between the rear end and the lead wire can be eliminated, and contact failure can be eliminated. (3) Unlike the conventional contact probe that prevents the fall by hooking the end face of the insulating coating on the tip side to the plate, the stopper can be fixed with, for example, a positioning plate of the probe unit, so that the fall can be prevented. A contact probe can be inserted from the plate on the measured object side. As a result, the contact probe can be easily inserted and set without disassembling the probe unit from the inspection apparatus. (4) Since the stopper can be formed by reducing the thickness of a part of the insulating film or removing a part of the insulating film, the processing area is very small and can be easily processed by laser processing etc. It can be processed and can be a low-cost contact probe. (5) Since one side or both sides of the end portion of the contact probe has a hemispherical shape, a needle shape, a conical shape, or a flat shape, there is no step between the metal conductor and the insulating coating. As a result, the contact probe can be easily inserted into the hole in the probe unit.

  The contact probe of the present invention is characterized in that the stopper portion is provided at a position within 1/3 from one end when the total length of the contact probe is 1.

  According to the present invention, for example, the concave stopper portion is provided at a position within 1/3 from one end of the contact probe. Therefore, the one end is set as the end portion on the opposite side of the measured object, and the distal end and the stopper portion on the measured object side By applying a weight between them and deflecting at least 2/3 of the total length, it is possible to obtain a contact pressure against the object to be measured and measure the electrical characteristics in a good state.

  The method of using the contact probe of the present invention for solving the above-described problems uses the contact probe of the present invention and has a probe having at least three plates with holes slightly larger than the outer diameter of the contact probe. A method of using a contact probe using a unit, wherein the contact probe is inserted into a hole of the plate, and a concave stopper provided on the contact probe is positioned in the middle of the plate After that, the contact probe is fixed so that only the positioning plate installed at the opposing position is slightly offset and the positioning plate is accommodated in the stopper portion. Used by the contact probe Characterized in that it is.

  According to the present invention, the contact probe is inserted into the hole of the plate, and the stopper portion provided on the contact probe is assembled so as to face the positioning plate located in the middle of the plate, and then assembled at the facing position. Only the positioning plate is slightly offset so that the positioning plate is accommodated in the stopper, so that the contact probe is fixed by the three plates acting in cooperation, and the contact probe is weighted in this state. Can give and bend. By using such a contact probe, it is possible to obtain a contact pressure with respect to the object to be measured and measure the electrical characteristics in a good state. And according to the usage method of this invention, the effect of said (1)-(5) can be show | played like the invention which concerns on the said contact probe.

  In the method of using the contact probe of the present invention, the stopper portion is provided at a position within 1/3 from the opposite end of the measured object when the total length of the contact probe is 1. The positioning plate is disposed so as to oppose the surface.

  According to the present invention, for example, the concave stopper portion is provided at a position within 1/3 from the opposite end of the object to be measured, and the positioning plate is disposed so as to face the position. By applying a load between the tip and the stopper portion and deflecting at least 2/3 of the entire length, a contact pressure against the object to be measured can be obtained and electrical characteristics can be measured in a good state.

  The contact probe manufacturing method of the present invention for solving the above problems is the method of manufacturing the contact probe of the present invention, wherein an insulating coating forming step of forming an insulating coating on the outer periphery of the metal conductor, and an insulating coating is formed. Cutting the cut metal conductor and grinding one or both ends of the cut metal conductor with insulating coating so that the cone has a hemispherical shape, a needle shape, a conical shape, and a hemispherical shape or a flat shape at the top. And a step of forming a concave stopper portion by thinning or removing a part of the insulating film with a laser.

  According to the present invention, the contact probe can be manufactured with a small number of processing steps, which is advantageous for cost reduction. In particular, in the step of forming the concave stopper portion, it is possible to easily reduce the thickness of a part of the insulating film or to remove a part of the insulating film by laser processing or the like. Since the processing area is extremely small, it is possible to shorten the processing time and man-hours.

  According to the contact probe of the present invention, (1) if the concave stopper portion is fixed by, for example, a positioning plate of the probe unit, the contact probe can be easily and accurately fixed in the probe unit. As a result, the centering of the end portion of the metal conductor is sufficient, and the lead wire can be brought into contact with the lead wire accurately and stably. In addition, (2) contact failure can be eliminated by eliminating generation of oxide powder due to repeated contact between the rear end of the contact probe and the lead wire. Further, (3) since the concave stopper portion can be fixed by, for example, a positioning plate of the probe unit to prevent the drop, the contact probe can be inserted from the plate on the measured object side. As a result, the contact probe can be easily inserted and set without disassembling the probe unit from the inspection apparatus. (4) The concave stopper can be formed by reducing the thickness of a part of the insulating film or removing a part of the insulating film. Can be processed easily, and a low-cost contact probe can be obtained. (5) Since there is no step between the metal conductor and the insulating coating on one side or both sides of the end portion of the contact probe, the contact probe can be easily inserted into the hole in the probe unit.

  According to the method of using the contact probe of the present invention, in addition to the effects (1) to (5), the contact probe is fixed by the three plates acting in cooperation, and the contact probe is weighted in this state. Therefore, by using such a contact probe, it is possible to obtain a contact pressure with respect to the object to be measured and measure the electrical characteristics in a good state.

  According to the contact probe manufacturing method of the present invention, the contact probe can be manufactured with a small number of processing steps, which is advantageous for cost reduction. In particular, the step of forming the concave stopper portion can be easily performed by laser processing or the like. As a result, processing time can be shortened and man-hours can be reduced.

  Hereinafter, a contact probe of the present invention, a method of using the same, and a method of manufacturing the same will be described with reference to the drawings. In addition, this invention is not limited to the following embodiment.

(Contact probe)
FIG. 1 is a schematic view showing an example of a contact probe according to the present invention. FIG. 1 (a) shows a front view of the whole, FIG. 1 (b) shows an enlarged sectional view of an end portion, and FIG. Represents an enlarged cross-sectional view of a concave stopper portion. 2 and 3 are schematic cross-sectional views for explaining a method for inspecting the electrical characteristics of the measurement object using the probe unit including the contact probe of the present invention. As shown in FIG. 1, a contact probe 1 of the present invention (hereinafter sometimes simply referred to as “probe 1”) includes a body portion A having an insulating coating 3 on the outer periphery of a pin-shaped metal conductor 2, and a metal conductor. 2 is a contact probe of a type that has an end portion B that does not have the insulating coating 3 at both ends, and obtains a contact pressure with respect to the object to be measured by applying a weight to both ends and deflects to measure the electrical characteristics. . In the present invention, one end or both ends of the end portion B have a hemispherical shape, a needle shape, a conical shape, or a flat shape, and the body portion A has a concave shape in which a part of the insulating coating 3 is thin. At least one concave stopper portion 4 from which a part of the stopper portion 4 or the insulating coating 3 is removed is provided.

  As shown in FIGS. 1 and 2, reference numeral 2 a is the “tip” of the metal conductor 2 on the side in contact with the electrode 12 of the measurement object 11 arranged on the measurement object side, and reference numeral 2 b is an inspection. This is the “rear end” of the metal conductor 2 on the side in contact with the lead wire 50 of an inspection apparatus (not shown) arranged on the apparatus side. Reference numeral 3a denotes a processed end face of the insulating coating 3 on the front end side, and reference numeral 3b denotes a processed end face of the insulating coating 3 on the rear end side. In the present application, “one end” refers to a portion including the tip (2a or 2b) of the metal conductor 2 and the processed end surface (3a or 3b) of the insulating coating 3, and “both ends” refers to the metal This refers to a portion including the ends 2 a and 2 b of the conductor 2 and the processed end faces 3 a and 3 b of the insulating coating 3.

  As the metal conductor 2, a metal wire (also referred to as “metal spring wire”) having high conductivity and high spring property is used. Examples of the metal used for the metal conductor 2 include metals having a wide elastic range, for example, copper alloys such as beryllium copper, phosphor bronze, copper silver alloy, tungsten, rhenium tungsten, steel (for example, high speed steel: SKH). Etc.) can be preferably used. Such metal conductor 2 is usually subjected to plastic working such as cold or hot wire drawing until the metal becomes a linear conductor of a predetermined diameter. The outer diameter of the metal conductor 2 is arbitrarily selected from the range of 20 μm or more and 400 μm or less, preferably 25 μm or more and 200 μm or less, particularly preferably 30 μm or more and 100 μm or less, depending on the interval between adjacent probes 1 in the probe unit 10. be able to.

  Further, from the viewpoint of easy attachment of the probe 1 to the probe unit 10, the straightness of the metal conductor 2 is preferably high, and specifically, the straightness is preferably 1000 mm or more in terms of the radius of curvature R. The metal conductor 2 with high straightness is subjected to straightening treatment before the insulating coating 3 is provided, or by straightening the long metal conductor 2 provided with the insulating coating 3 as described later. Obtainable. The straightening process here is performed, for example, by a rotary die type straightening apparatus or the like. By providing such straightness, it is possible to prevent the probe 1 from becoming difficult to enter the guide holes of the plates 20 and 30 when the probe 1 is attached to the probe unit 10.

  The shape of the front end 2a and / or the rear end 2b of the metal conductor 2 may be a hemispherical shape as shown in FIG. 1, a conical shape as shown in FIG. 4 to be described later, or a conical shape having a hemispherical shape at the top. Further, it may be formed of any one selected from a conical shape having a flat shape at the top, and the like. The “hemispherical shape” and “conical shape” here include an accurate hemisphere and a cone, but also include a substantially cone and a substantially hemisphere.

  The front end 2a or the rear end 2b of the metal conductor 2 is provided with a plating layer in order to suppress an increase in the contact resistance value between the metal conductor 2 and the electrode 12 of the measured object 11 or the lead wire 50 of the inspection apparatus. It may be. Examples of the metal constituting the plating layer include metals such as nickel, gold, and rhodium, and alloys such as gold alloys. The plating layer may be a single layer or a multilayer. Preferred examples of the multi-layered plating layer include those in which a gold plating layer is formed on a nickel plating layer.

  The insulating coating 3 is provided on the metal conductor 2 and acts to prevent short circuits by preventing the probes from contacting each other when inspecting the electrical characteristics of the measurement object 11. The insulating coating 3 may be provided on the metal conductor 2, that is, on the outer periphery of the metal conductor 2 in the longitudinal direction, and may be provided directly or via another layer. May be.

  The insulating film 3 is not particularly limited as long as it is an insulating film, but it is any one selected from polyurethane resin, nylon resin, polyester resin, epoxy resin, polyesterimide resin, polyamide resin and polyamideimide resin. Is preferred. Usually, it is formed of one kind of resin. Since the insulating film made of these resins has different heat resistance, it can be arbitrarily selected in consideration of the heat generated during the inspection. For example, when more heat resistance is required, the insulating coating 3 is preferably formed of a polyesterimide resin, a polyamideimide resin, or the like. The thickness of the insulating coating 3 may be a thickness that can ensure electrical insulation, and is appropriately set within the range of 5 μm to 50 μm in consideration of the relationship with the diameter of the metal conductor 2. In the present invention, the insulating coating 3 is preferably formed as a baked enamel coating. As will be described later, the baking enamel coating is formed in a continuous process by repeated application of coating and baking, so that the productivity is good, the adhesion between the metal conductor 2 is high, and the coating strength is higher. be able to.

  As shown in FIGS. 1A and 1C, the main feature of the present invention is that the body portion A of the probe 1 has a concave stopper portion 4 or insulating coating 3 in which a portion of the insulating coating 3 is thin. It is in having one or more concave-shaped stopper parts 4 from which a part of is removed. The concave stopper portion 4 (hereinafter also referred to as the stopper portion 4) is formed in the middle of the plate 30 after inserting the probe 1 into the hole of the plate 30, as will be described in detail in the section of the use method described later. The probe 1 is fixed by slightly offsetting only the positioning plate 32 positioned in the position and engaging the positioning plate 32 with the stopper portion 4.

  The stopper portion 4 is preferably provided at a position within 1/3 from one end when the total length of the probe 1 is 1. The stopper portion 4 is provided at such a position, and one end thereof is set as an end portion on the opposite side of the measured object 11, and a weight is applied between the distal end 2a of the metal conductor 2 on the measured object side and the stopper portion 4 so that at least 2 of the total length is provided. By deflecting the portion of / 3, the contact pressure with respect to the measured object 11 can be obtained and the electrical characteristics can be measured in a good state. Note that “1/3” is a preferable value specified because it is easy to bend the probe 1 if at least 2/3 of the entire length is left. If the deflection of the probe 1 can be given as in a case where the length of the probe 1 is long, it may be a case where it exceeds 1/3 from one end.

  The width W of the stopper portion 4 in the longitudinal direction of the probe 1 is not particularly limited because it is determined by the relationship with the shape and dimensions of the positioning plate 32 (see FIG. 2) that engages with the stopper portion 4. A width W of about 300 μm is preferably employed.

  The depth of the stopper portion 4 is determined in consideration of the fact that it does not come off from the engaged positioning plate 32. The depth is determined by the weight applied to the probe 1 or the insulation coating so as to cause deflection. The relationship with the thickness of 3 is considered. For example, when the load is large, it is necessary to increase the depth of the stopper portion 4 so that it does not come off the engaged positioning plate 32. On the other hand, when the load is small, the depth of the stopper portion 4 is required. You can make it shallower. Therefore, the depth of the stopper portion 4 cannot be generally defined, but usually a depth of about 5 to 30 μm is preferably employed.

  The stopper portion 4 is not particularly limited as to whether the insulating coating 3 is formed with a reduced thickness or is formed by removing the insulating coating 3. For example, when the thickness of the insulating coating 3 is thicker than the required depth of the stopper portion 4, the stopper portion 4 may be formed by making the insulating coating 3 thin or by removing the insulating coating 3. However, when the thickness of the insulating coating 3 is approximately the same as the required depth of the stopper portion 4, the stopper portion 4 is formed by removing the insulating coating 3. . The stopper portion 4 can be formed using, for example, an organic film processing method such as a carbon dioxide laser or an excimer laser. In particular, these processing methods do not easily damage the metal conductor 2. Therefore, it can be preferably used.

  In the end surfaces 4a and 4b of the insulating coating 3 in the stopper portion 4, it is preferable that the shape of the end surface on the side where the positioning plate 32 abuts rises at an acute angle rather than gently. For example, the angle with the metal conductor surface is preferably 30 ° or more, and more preferably 60 ° or more. In the probe 1 in which the end surface having such a configuration is a contact surface of the positioning plate 32, the positioning plate 32 is not detached from the stopper portion 4 even when a load is applied to the probe 1 so as to cause deflection. Can be prevented.

  The number of the stopper parts 4 should just be at least one, and may be two or more. When the number of the stopper portions 4 is one, as shown in FIG. 2, it can be handled by a set of three plates 30 (plate / positioning plate / plate), but in the case of two, two positioning plates 32 are required. Therefore, at least five plates (plate / positioning plate / plate / positioning plate / plate) are required. By fixing two or more stopper portions 4 with two or more positioning plates corresponding to each of them, the probe 1 can be fixed more reliably even when a large load is applied.

  According to the probe 1 of the present invention having such a stopper portion 4, (1) since the probe 1 can be easily and accurately fixed in the probe unit 10, centering of the end portion 2 b of the metal conductor 2 is sufficient, The lead wire 50 can be contacted accurately and stably. (2) If the probe 1 can be fixed in the probe unit 10 as described above, the rear end 2b of the probe 1 and the lead wire 50 are always kept in contact with each other, and the tip end side of the probe 1 is bent. Further, since it can be brought into contact with the measured object 11, generation of oxide powder due to repeated contact between the rear end 2b and the lead wire 50 can be eliminated and contact failure can be eliminated. In addition, (3) unlike the conventional probe in which the end face of the insulating film on the tip side is hooked on the plate to prevent the fall, the stopper portion 4 can be fixed by, for example, the positioning plate 32 of the probe unit 10 to prevent the fall. Therefore, the probe 1 can be inserted from the plate 20 on the measured object side. As a result, the probe 1 can be easily inserted and set without disassembling the probe unit 10 from the inspection apparatus. Further, (4) the stopper portion 4 can be formed by reducing the thickness of a part of the insulating film 3 or removing a part of the insulating film 3, so that the processing region is extremely small, and laser processing or the like is possible. Can be processed easily, and a low-cost contact probe can be obtained.

  Here, the shape of one end or both ends A of the probe 1 will be described. FIG. 4 is a sectional view showing an example of one or both ends of the contact probe of the present invention. The end B of the probe 1 of the present invention may be any of a hemispherical shape, a needle shape, a conical shape, or a flat shape. In particular, it is preferable that the shape of the end portion B shows a form in which the metal conductor 2 and the insulating coating 3 are processed at the same time from the viewpoint of cost reduction due to man-hour reduction. As the processing method of the end portion B, grinding processing is usually applied, but other processing methods may be adopted as long as a similar shape can be expressed. Specifically, as shown in FIG. 4, the shape of the end is any one selected from a hemispherical shape, a conical shape, a conical shape having a hemispherical shape at the top, a conical shape having a flat shape at the top, and the like. In addition, it is preferable that such a shape is configured to have the end faces 3a and 3b of the insulating coating 3 having a shape along the shape of the end portions 2a and 2b of the metal conductor 2.

  In such an end shape, the lengths L1 to L4 of the protruding metal conductor 2 are in the range of 0.01 mm or more and 0.2 mm or less, preferably 0.1 mm or less. When the wire diameter of the metal conductor 2 is small, the protrusion lengths L1 to L4 of the metal conductor 2 are shifted to the lower limit side, and when the wire diameter of the metal conductor 2 is large, the protrusion lengths L1 to L1 of the metal conductor 2 are shifted. L4 shifts to the upper limit side. There are various shape elements such as the curvature of the curved surface in FIGS. 4A and 4C, the angle of the inclined surface in FIGS. 4B and 4D, and the area of the flat surface at the top in FIG. The value of can be set arbitrarily. In this way, by making one side or both sides of the end portion B of the probe 1 into an integral shape formed of a hemispherical shape, a needle shape, a conical shape or a flat shape, there is no step between the metal conductor 2 and the insulating coating 3, As a result, the probe 1 can be easily inserted into the hole in the probe unit 10.

(Contact probe manufacturing method)
Next, the manufacturing method of the contact probe of this invention is demonstrated. FIG. 5 is a process flow diagram showing an example of the probe manufacturing method of the present invention. As shown in FIG. 5, the method for manufacturing the probe 1 of the present invention is a method for manufacturing the probe 1 of the present invention, in which an insulating film forming step of forming an insulating film 3 on the outer periphery of the metal conductor 2 and insulation A cutting step of cutting the metal conductor 2 on which the coating 3 is formed, and grinding the end B on one side or both sides of the cut metal conductor 2 with an insulating coating, to form a hemispherical shape, a needle shape, a conical shape, and a top portion A concave shape of the stopper portion 4 is formed by thinning or removing a part of the insulating coating 3 with a laser, and a grinding step for selecting one of a conical shape having a hemispherical shape or a flat shape and a flat shape. A stopper portion forming step.

  A normal enameled wire manufacturing apparatus (manufacturing line) can be used in the insulating film forming step. For example, an enamel paint is applied to a linear metal conductor (hereinafter also referred to as a wire) fed from a wire feeding device such as a bobbin in a paint tank, and then a paint such as a die or felt provided immediately after that. Handle the paint on the surface of the wire to a substantially uniform thickness with a drawing tool, then introduce the wire into a high-temperature baking furnace such as an electric heating furnace or hot air circulating furnace, and remove the solvent in the paint applied on the wire in the furnace. The process of volatilizing and removing the paint is reactively cured, and a cured coating layer is formed on the surface of the wire, and is derived from the baking furnace. The process of passing the derived wire through the paint tank, paint squeezing tool and baking furnace is repeated several times. After a cured coating film layer having a desired thickness is formed on the surface of the wire, the enamel coating film is continuously formed by winding it on a winding device such as a take-up bobbin by a pulling device such as a capstan.

  By using such an enameled wire manufacturing apparatus, an insulating film having a uniform film thickness can be easily formed. In the insulating coating forming process, the enamel coating and baking are usually repeated until the insulating coating has a desired average film thickness. The enamel paint is prepared by mixing the resin already described in the description of the probe and an organic solvent.

  It is desirable to increase the straightness of the metal conductor before the cutting step. As a means for that, (1) Obtain a metal conductor with high straightness and coat the enamel with the metal conductor, or (2) Straighten the metal conductor and use the metal conductor with the enamel coating. Or (3) a straight work in which straightening is performed after the enamel coating is applied to the metal conductor. Straightening can be performed by current annealing while applying axial tension to a long metal conductor. In addition, as a metal conductor with an insulation film with high straightness, the material which concerns on the patent (patent 3415442) which Tokyo Special Electric Cable Co., Ltd. which is this patent applicant has, for example is used preferably.

  The cutting step is a step of cutting the long metal conductor 2 on which the insulating coating 3 is formed to a predetermined length. In this cutting step, for example, a long-sized metal conductor having a baking enamel film formed as the insulating film 3 is formed into a predetermined length by taking into account that the end is processed using a standard cutting device or the like. Disconnect. The long metal conductor on which the baking enamel film provided for the cutting process is formed is repeatedly applied with an enamel paint and baking on the long metal conductor having spring properties, as already described in the description of the probe 1. It is formed by an insulating film forming process (baking enamel insulating coating process) to be performed.

  In the grinding process, the end portions (2a, 2b) of the metal conductor 2 and the end surfaces (3a, 3b) of the insulating coating 3 are usually applied to the end portions B on one side or both sides of the cut metal conductor 2 with insulating coating. Is a grinding process. By this processing step, the shape composed of the end portions (2a, 2b) of the metal conductor 2 and the end surfaces (3a, 3b) of the insulating coating 3 has a hemispherical shape, a conical shape, a conical shape having a hemispherical shape at the top, and Any shape selected from conical shapes having a flat shape at the top is used. Examples of the grinding method include grinding using emery paper and grinding using a diamond wheel. The tip shape can be obtained by rotating the probe 1 brought into contact with a rotating emery paper or a diamond wheel at a predetermined angle (the shapes shown in FIGS. 4B and 4D), and further, emery paper or diamond. It can be obtained by changing the angle with respect to the wheel or the like (the shapes of FIGS. 4A and 4C). Moreover, as a grinding apparatus, the commercially available grinding machine which can grind a pin-shaped metal material may be used, for example, you may use the grinding apparatus of Unexamined-Japanese-Patent No. 2005-3516.

  The stopper portion forming step is a step of forming a concave stopper portion 4 by thinning or removing a part of the insulating coating 3 with a laser. Specifically, laser irradiation means that can be preferably applied to an organic coating such as a carbon dioxide laser or an excimer laser can be applied. Such a processing method is preferable because the metal conductor 2 is hardly damaged.

  Control of the adjustment of the width W of the stopper portion 4 can be performed by arranging a laser shielding mask between the probe 1 which is an irradiation object and the laser light source, and adjusting the position of the mask. Further, there is no problem when the stopper portion 4 from which the insulating coating 3 has been removed is formed, but when the insulating coating 3 is removed by a predetermined depth, for example, by adjusting the laser output and the processing time, Depth can be controlled. The angle of the end surfaces 4a and 4b of the stopper portion 4 can be controlled by adjusting the distance between the probe 1 and the laser shielding mask, for example.

  In addition, you may provide the plating process of plating the edge part (namely, edge part which the metal conductor exposed) after grinding etc. as needed. By this plating step, a plating layer for reducing contact resistance can be formed at the end.

  As described above, according to the method for manufacturing the probe 1 of the present invention, the probe 1 can be manufactured with a small number of processing steps, which is advantageous for cost reduction. In particular, in the step of forming the concave stopper portion 4, it is possible to easily reduce the thickness of a part of the insulating film 3 or remove a part of the insulating film 3 by laser processing or the like. In addition, since the processing area is extremely small, it is possible to shorten the processing time and man-hours.

(How to use contact probe)
Next, a method for inspecting electrical characteristics using the above-described probe of the present invention will be described with reference to FIGS. The probe 1 of the present invention is attached to a probe unit 10 and used for inspection of the electrical characteristics of an object to be measured such as a circuit board. As shown in FIG. 2, the probe unit 10 includes a plurality of thousands of probes 1, a plate 20 that guides the probes 1 to the electrodes 12 of the measured object 11, and the probes 1 to lead wires 50 of the inspection device And a plate 30 for guiding. The plate 30 on the inspection apparatus side has a guide hole slightly larger than the outer diameter of the probe 1, and the guide hole guides the metal conductor 2 of each probe 1 to the lead wire 50. The plate 20 on the measured object side has a guide hole that is slightly larger than the outer diameter of the probe 1, and the guide hole guides the metal conductor 2 of each probe 1 to the electrode 12. The probe unit 10 to which the probe 1 of the present invention is attached has a structural feature in that it has at least three plates 30 with holes slightly larger than the outer diameter of the probe 1.

  The position of the probe unit 10 and the measured object 11 are controlled so that the probe 1 and the electrode 12 correspond to each other when the electrical characteristics of the measured object 11 are inspected. In the inspection of the electrical characteristics, either the probe unit 10 or the measured object 11 is moved up and down, and the tip 2a of the probe 1 is pressed against the electrode 12 of the measured object 11 with a predetermined pressure using the elastic force of the probe 1. Is done. At this time, the rear end 2b of the probe 1 is always in contact with the lead wire 50, and an electric signal from the measured object 11 is sent through the lead wire 50 to an inspection device (not shown). 2 and 3 indicates a lead wire holding plate.

  The method of using the probe of the present invention is a method of using a contact probe using the probe unit 10 as shown in FIGS. The feature of the present invention is that the positioning plate is formed by inserting the probe 1 into the hole of at least three plates 30 and positioning the concave stopper portion 4 provided on the probe 1 in the middle of the plate 30. Then, the probe 1 is fixed so that only the positioning plate 32 incorporated in the opposing position is slightly offset and engaged so that the positioning plate 32 is accommodated in the stopper portion 4. In this state, the probe 1 is to be used. According to the present invention, the probe 1 is fixed by the three plates 30 acting in cooperation with each other, and the probe 1 can be bent while being kept in that state. By using such a probe 1, it is possible to obtain a contact pressure with respect to the measured object 11 and measure the electrical characteristics in a good state. Furthermore, according to the method of use of the present invention, the same effects (1) to (5) as described in the invention relating to the contact probe can be achieved.

  This will be described in detail with reference to FIG. FIG. 2A is a schematic view showing a state in which the probe 1 according to the present invention is inserted into the plates 20 and 30 in the probe unit 10 and the stopper portion 4 is set at a predetermined position, and FIG. It is the schematic which shows the state which offset the positioning plate 32 and was engaged with the stopper part 4, FIG.2 (C) is schematic which shows the bending state of the contact probe at the time of a test | inspection.

  First, as shown in FIG. 2A, the probe 1 according to the present invention is inserted into the plates 20 and 30 in which holes are formed at a predetermined interval (for example, 15 mm). At this time, the hole positions of the plates 20 and 30 are aligned so that the probe 1 can be easily inserted. In particular, in order to align the positions of the holes of the three-plate plate 30, a means such as making a small first through hole with the holes aligned and putting a pin into the first through hole may be used. . By doing so, the probe 1 can be easily inserted into the holes of the plate 20 and the plate 30 having at least three plates. Further, in order to incorporate the stopper portion 4 provided on the probe 1 so as to face the positioning plate 32 positioned in the middle of the plate 30, as shown in FIG. If the positional relationship between the probe unit 10 and the holding plate 40 is regulated so that the position where the portion 2b abuts against the lead wire 50 becomes the opposite position, the stopper portion 4 can be easily positioned.

  Next, as shown in FIG. 2B, in a state where the stopper portion 4 is disposed so as to face the positioning plate 32, for example, the pin is removed from the first through hole, and only the positioning plate 32 is slightly removed. Offset. The offset slides the center positioning plate 32 by a predetermined amount in consideration of the depth of the stopper portion 4 and the like. The positioning can be performed by providing a positioning projection at a predetermined position to be slid and sliding the middle positioning plate 32 until it contacts the positioning projection. In order to accurately hold at that position, a small second through hole is made in the state where it is held at that position, and a means such as a pin used for the first through hole is inserted into the second through hole. Thus, the positioning plate 32 can be fixed and does not move during the inspection, so that stable measurement can be performed during the inspection.

  Finally, as shown in FIG. 2C, after the positioning plate 32 is offset to a predetermined position and engaged with the stopper portion 4 to fix the probe 1, the probe 1 is in contact with the electrode 12 such as an electronic component during inspection. As shown in the figure, a deflection occurs between the tip on the electrode side and the stopper portion 4, and a contact pressure with respect to the measured object 11 can be obtained to measure the electrical characteristics in a good state.

  The stopper portion 4 is provided at a position within 1/3 from the opposite end 2b of the measured object 11 when the total length of the probe 1 is 1, and a positioning plate is provided so as to face the position. 32 is preferably arranged. With such a configuration, a load is applied between the tip 2a on the measured object side and the stopper portion 4 to deflect at least 2/3 of the entire length, thereby obtaining a contact pressure with respect to the measured object 11 to obtain electrical characteristics. It can be measured in a good state.

  FIG. 3 shows an example in which the shape of the positioning plate 32 is different from that of FIG. Specifically, a counterbore portion 34 having a large diameter is provided in the hole of the positioning plate 32 on the lead wire side. By providing the counterbore part 34, a portion having a normal hole diameter becomes an engaging part that engages with the stopper part 4, and the counterbore part 34 becomes an abutting part to the insulating coating end surface 4b on the lead wire side. .

  This aspect is basically the same as described in FIG. The difference is that since the engaging portion of the positioning plate 32 has a smaller width than that in the case of FIG. 2, there is a manufacturing advantage that the stopper portion 4 can be easily formed by laser processing or the like. is there. In addition, when the width of the engaging portion of the positioning plate 32 and the width of the stopper portion 4 opposed thereto are reduced, the accuracy of the alignment between the two is required, but in that case as well as in the case of FIG. The probe 1 can be accurately aligned by, for example, bringing the lead wire side end (rear end) 2b of the probe 1 into contact with the lead wire 50.

  Further, as shown in FIG. 3B, after the positioning plate 32 is offset and the engaging portion of the positioning plate 32 is engaged with the stopper portion 4, the lead wire is connected as shown in FIG. If the supporting plate 40 to be supported is shifted so as to be pressed against the plate 31, the rear end 2 b of the probe 1 is pushed by the supporting plate 40, and the portion with the normal hole diameter becomes an engaging portion that engages with the stopper portion 4. The insulating coating end surface 4b of the stopper portion 4 contacts the counterbore portion 34. At this time, the end portion 2b of the probe 1 is pressed against the lead wire 50 by the repulsive force of the resin material constituting the insulating coating 3. Will be in contact. As the insulating film having repulsive force, a polyurethane film or the like can be preferably exemplified.

  Therefore, in the present invention, the tip 2a on the measured object 11 side can stably come into contact with the electrode 12 of the measured object 11 by the deflection of the probe 1, while the rear end 2b on the lead wire side has an insulating coating. There is an advantage that the resin wire can be stably contacted with the repulsive force of the resin material.

  Hereinafter, the present invention will be described more specifically with reference to examples. The following examples are merely examples, and the present invention is not limited to the following specific examples.

(Example 1)
As the metal conductor 2, a long straight beryllium copper wire (outer diameter 0.10 mm) whose straightness was straightened to 1500 mm with a radius of curvature R in advance was used. In addition, a polyurethane resin-based enamel paint (manufactured by Tohoku Paint Co., Ltd., trade name: TPU5100) is used as a coating for the insulating coating, and a polyurethane coating 3 having a thickness of 0.015 mm is continuously formed by an insulating coating baking apparatus not shown. And a straight beryllium copper wire with an insulating coating (hereinafter abbreviated as an insulating straight beryllium copper wire) was produced.

  Next, the said insulation straight beryllium copper wire was cut | disconnected to 25 mm length with the fixed length cutting device. Next, the end B of the insulated straight beryllium copper wire cut into a regular length was ground into a hemispherical shape by a grinding apparatus to form an end B having a predetermined shape. In addition, the grinding process pressed and grind | pulverized the edge part B of the insulation straight beryllium copper wire cut | disconnected on the rotating disk which stuck emery paper, and processed the beryllium copper wire and the insulating film into hemispherical shape simultaneously. Next, with the carbon dioxide laser, the insulating coating 3 is laser processed so that the 3 mm portion is the center and engages with the positioning plate 32 having a width of 1 mm to be used from the lead wire side end 2b side. The concave stopper portion 4 having a width of 0.2 mm was formed. Thus, the contact probe 1 according to Example 1 was manufactured.

(Example 2)
After the laser processing, the exposed metal conductor 2 is plated to form two plating layers (total film thickness 2 μm) consisting of a nickel plating layer (film thickness 1.7 μm) and a gold plating layer (film thickness 0.3 μm). A contact probe 1 according to Example 2 was produced in the same manner as in Example 1 except that it was formed.

It is the schematic which shows an example of the contact probe of this invention, The figure (a) represents the whole front view, The figure (b) represents the expanded sectional view of an edge part, The figure (c) is concave shape. The expanded sectional view of the stopper part of is represented. It is a schematic cross section for demonstrating the method to test | inspect the electrical property of a to-be-measured object using the probe unit provided with the contact probe of this invention. It is a schematic cross section for demonstrating the method to test | inspect the electrical property of a to-be-measured object using the probe unit provided with the contact probe of this invention. It is sectional drawing which shows the example of a form of the edge part of the contact probe of this invention. It is a process flow figure showing an example of the manufacturing method of the probe of the present invention. It is the schematic (A) which shows the state which set the conventional contact probe to the probe unit, and the schematic (B) which shows the state which is inspecting the to-be-measured object by bending the contact probe.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Contact probe 2 Metal conductor 2a, 2b End part 3 Insulation film 3a, 3b End face 4 Recessed stopper part 4a, 4b End face 10 Probe unit 11 Measured object 12 Electrode 20 Measured object side plate 30 Inspection apparatus side plate 31 , 33 Plate 32 Positioning plate 34 Stepped portion 40 Lead wire holding plate 50 Lead wire A Body portion B End portion W Stopper portion width L1 to L4 Length of metal conductor

Claims (5)

A body portion having an insulating coating on the outer periphery of the pin-shaped metal conductor, and an end portion having no insulating coating on both ends of the metal conductor, and applying weight to both ends to bend the body to be measured In a contact probe that measures electrical characteristics by obtaining contact pressure,
One or both sides of the end portion of the contact probe are formed in a hemispherical shape, a needle shape, a conical shape, or a flat shape,
The body portion of the contact probe has at least one concave stopper portion in which a part of the insulating coating is thin or a concave stopper portion from which a part of the insulating coating is removed. .   2. The contact probe according to claim 1, wherein the stopper portion is provided at a position within 1/3 from one end when the total length of the contact probe is 1. 3. A method of using a contact probe using the contact probe according to claim 1 or 2 and using a probe unit having at least three plates with holes slightly larger than the outer diameter of the contact probe,
The contact probe is inserted into the hole of the plate, and a concave stopper provided in the contact probe is assembled so as to face the positioning plate located in the middle of the plate,
After that, slightly offset only the positioning plate incorporated in the facing position, the contact probe is fixed so that the positioning plate fits in the stopper portion,
A method of using a contact probe, wherein the contact probe is used in that state. The stopper portion is provided at a position within 1/3 from the opposite end of the measured object when the total length of the contact probe is 1.
The method of using a contact probe according to claim 3, wherein the positioning plate is disposed so as to face the position. A method of manufacturing a contact probe according to claim 1 or 2,
An insulating film forming step of forming an insulating film on the outer periphery of the metal conductor;
Cutting the metal conductor on which the insulating coating is formed;
About one end or both ends of the cut metal conductor with an insulating coating, the end of the metal conductor is ground and processed into a hemispherical shape, a needle shape, a conical shape, a conical shape having a hemispherical shape or a flat shape at the top, and a flat shape. A process of making any shape selected from:
And a step of forming a concave stopper by thinning or removing a part of the insulating film with a laser.

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