JP2010181236A - Probe pin and probe unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an IC socket for receiving a probe pin for applying different pressures to a solder and a pad, and flowing a relatively-high current. <P>SOLUTION: The probe pin 130 includes plungers 131, 135 disposed on both ends and springs 132, 134 having different strengths connected to the plungers 131, 135. The springs 132, 134 have different lengths from an axial center to a spiral section. The IC socket includes a stepped hole 120 for partially receiving the probe pin and a conductive part 123 positioned so as to contact and bridge at least two points of the probe pin 130 on the inner wall of the hole 120. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a probe pin and a probe unit, and more particularly to a probe pin and a probe unit for IC inspection.

  Conventionally, there is a probe unit disclosed in Patent Document 1 as a probe unit used for IC inspection. The probe used in this unit includes a lower probe pin, a guide tube connected to the connecting portion of the pin, an upper probe pin having a guide shaft portion inserted into the guide tube, and a spring that is externally fitted to the guide shaft portion. And have. The upper guide plate is provided with an upper opening through which the upper probe pin collar is inserted, and the lower guide plate has a larger outer diameter than the lower probe pin collar and smaller than the lower probe pin collar. A lower opening through which the contact portion is inserted is provided, and the lower probe pin flange is in contact with the peripheral edge of the lower opening of the lower guide plate.

JP 2008-298792 A

  By the way, at the time of inspection of a conductor pattern or IC of a package substrate, a force exceeding several tens of grams is required as a pressing force against solder formed on the package substrate. In the case of Patent Document 1, a force exceeding several tens of grams is required as a pressing force related to the lower probe pin. And this power is expected to increase in the future.

  On the other hand, it is not preferable to apply an excessive pressing force to the pad on the counter substrate of the package substrate. In the case of Patent Document 1, it is not preferable that the pressing force related to the upper probe pin is excessive. This is because, when an excessive pressing force is applied to the pad, the counter substrate on which the pad is formed is deformed by the pressing force.

  Therefore, when the probe unit of Patent Document 1 is used, a technique of increasing the strength of the counter substrate has been employed to prevent the counter substrate from being deformed. Typically, the counter substrate is made thicker than necessary only for the purpose of increasing its strength.

  Further, when the IC is inspected, the electrical characteristics of the IC are inspected by electrically connecting the solder and the pad. Several years ago, the magnitude of the current flowing through the probe pin was about several hundred mA. However, today, the current flowing through the probe pin is required to be as large as several A.

  The current path of the probe pin was a spring and a barrel constituting the probe pin. However, these days, the probe pin is very miniaturized. Therefore, there is a limit to earning the physical size of the spring and the barrel. It was considered impossible.

  Therefore, an object of the present invention is to enable different pressing forces to be applied to solder and pads.

  Another object of the present invention is to allow a relatively large current to flow with respect to the probe pin.

In order to solve the above problems, the probe pin and the probe unit of the present invention are:
Plungers located at both ends (for example, plungers 131 and 135 in FIG. 1);
And elastic bodies having different strengths (for example, the springs 132 and 134 in FIG. 1), each end of which is connected to each plunger.

  Thus, since the probe pin and the probe unit of the present invention are provided with elastic bodies having different strengths and conductivity, different pressing forces can be applied to the contact objects of the plungers. . Further, the use of a plurality of elastic bodies has an advantage that the current path can be increased.

It is a typical block diagram of the probe pin 130 used for the probe unit of Embodiment 1 of this invention. FIG. 2 is a cross-sectional view illustrating a schematic configuration of a probe unit 100 including the probe pin 130 and the socket 120 in which the probe pin 130 is accommodated illustrated in FIG. 1. FIG. 3 is a diagram showing a state in which the probe unit 100 shown in FIG. 2 is in contact with a pad 310 formed on a counter substrate 300. FIG. 3 is a diagram showing a state in which the probe unit 100 shown in FIG. 2 is in contact with solder 210 formed on a package substrate 200. It is a typical block diagram of the probe pin 130 used for the probe unit of Embodiment 2 of this invention.

DESCRIPTION OF SYMBOLS 100 Probe unit 120 Socket 121 1st board | substrate 122 2nd board | substrate 123 Conductive part 124 Round 131 Plunger 132 Spring 133 Barrel 134 Spring 135 Plunger 200 Package board 300 Opposite board

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification, the upper side is described as upper (for example, upper surface, upper side, upper end) and the lower side is described as lower (for example, lower surface, lower side, lower end) with reference to the drawings.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a probe pin 130 used in the probe unit according to the first embodiment of the present invention.

  FIG. 1 shows a plunger 131, a spring 132, a barrel 133, a spring 134, and a plunger 135, which will be described below.

  The plunger 131 includes a tip 131a that contacts the solder on the package substrate to be inspected, a column 131b extending from the tip 131a, a flange 131c positioned below the column 131b, and a flange 131c. It has a defining portion 131d for positioning the spring 132, and a leg portion 131e extending from the defining portion 131d and accommodated in the barrel 133. The plunger 131 may be made of any material, but as an example, carbon tool steel can be adopted.

  The tip 131a has a protrusion shape (so-called crown type) having a plurality of protrusions in order to achieve good contact with the solder on the package substrate to be inspected. Good. The column part 131b is passed through a hole provided in a first substrate (this will be described later) constituting a socket in which the probe pin 130 is accommodated. The flange 131 c contacts the first substrate, and the lower surface receives the upper end 132 a of the spring 132. The defining portion 131 d receives the inside of the upper end portion of the spring 132. The leg portion 131 e has a relatively thin base end and a relatively thick tip end, and the boundary portion has a shape corresponding to the taper of the barrel 133.

  The spring 132 has an upper end 132a received by the flange 131c of the plunger 131 and a lower end 132b received by a step portion of a through hole formed in the socket (this point will be described later). A spring 132 having a relatively large spring constant is used. In the present embodiment, a pressing force of about several tens of grams (for example, 30 g to 60 g) can be applied to the solder on the package substrate to be inspected. Specifically, the spring 132 has a relatively large length from the axial center to the spiral portion, that is, the diameter of the spring. Any material may be used for the spring 132. As an example, piano wire, copper wire, stainless steel including SUS304, SUS316, or the like can be used.

  Here, the barrel 133 has a cylindrical shape having a taper at both ends. However, the barrel 133 may be formed with several depressions from its side by roll caulking or punching so that the plunger 131 or the like does not fall off. In the barrel 133, a spring 134 and a plunger 135 are accommodated in addition to the leg portion 131e of the plunger 131. Any material may be used for the barrel 133, but as an example, brass, phosphor bronze, or the like may be employed.

  The spring 134 has an upper end 134 a received by the tip of the leg 131 e of the plunger 131 and a lower end 134 b received by the upper end of the plunger 135. The spring 134 has a relatively small spring constant. In this embodiment, a pressing force of about 10 g (for example, 5 g to 15 g) can be applied to the pad on the counter substrate. Specifically, the spring 134 has a relatively small diameter. Any material may be used for the spring 134, but as an example, a piano wire, a copper wire, or the like may be employed.

  The plunger 135 includes a front end portion 135a that is in contact with a pad on the counter substrate, a column portion 135b that extends from the front end portion 135a, and a leg portion 135c that is located above the column portion 135b and is accommodated in the barrel 133. Have Any material may be used for the plunger 135, but beryllium copper alloy may be employed as an example.

  The distal end portion 135a has a planar shape in order to achieve good contact with the pad on the counter substrate. The column part 135b is relatively thin, and the leg part 135c is relatively thick. The leg portion 135 c receives the lower end 134 b of the spring 134 at the upper end and receives a taper on the lower side of the barrel 133 at the lower end.

  In addition, the probe pin 130 of this embodiment is not limited to the shape, structure, and layout shown in FIG. Therefore, for example, FIG. 1 shows a structure in which the spring 132 having a relatively small diameter and the spring 132 having a relatively large diameter are covered by focusing on the mutual positional relationship between the springs 132 and 134. However, these positional relationships may be interchanged.

  In the present embodiment, the case where the springs 132 and 134 are used as an example of the elastic body has been described as an example. However, instead of this, for example, conductive rubber may be used. In this case, the conductive rubbers may have different strengths depending on the required pressing force.

  FIG. 2 is a cross-sectional view showing a schematic configuration of the probe unit 100 having the probe pin 130 and the socket 120 in which the probe pin 130 is accommodated shown in FIG. For convenience of explanation, FIG. 2 shows a state in which the two probe pins 130 are accommodated in the socket 120, but actually, a large number of probe pins 130 are accommodated.

  The socket 120 shown in FIG. 2 includes a first substrate 121, a second substrate 122, a conductive portion 123, and a round 124, which will be described below.

  The first substrate 121 is formed with holes 121a through which the column portions 131b of the plungers 131 of the plurality of probe pins 130 pass. The diameter of each hole 121 a is larger than the diameter of the column portion 131 b of the plunger 131 and smaller than the flange portion 131 c of the plunger 131.

  The second substrate 122 has through holes 122a corresponding to the holes 121a. The through hole 122a is provided with two steps, both of which are located below. The step on the upper side of the through hole 122 a receives the lower end 132 b of the spring 132. The step on the lower side of the through hole 122a receives a taper on the lower side of the barrel 133.

  The conductive portion 123 is formed on the inner wall of the through hole 122a. For example, gold or copper may be used as the material of the conductive portion 123. In this case, the conductive portion 123 may be formed by a plating process or the like. FIG. 2 shows a state in which the conductive portion 123 is formed on the entire inner wall of the through hole 122a. However, as will be described later, at least two points of the probe pin 100 on the inner wall of the through hole 122a. The conductive layer 123 may be positioned so as to be in contact with each other.

  The round 124 is integrally formed with the conductive portion 123. The round 124 is a portion that contacts the pad on the counter substrate. Note that the round 124 is not necessarily formed, and it may be determined whether or not the round 124 can be formed in consideration of a wiring pitch or the like.

  In the probe unit 100 shown in FIG. 2, the probe pins to be accommodated in the socket 120 are all the probe pins 130 shown in FIG. 1, but some or all of them may be known probe pins.

  Further, in the present embodiment, the aspect in which the through hole 122a is formed in the second substrate 122 has been described. However, instead of the second substrate 122, for example, two pieces separated in the middle of the probe pin You may use the resin body and may form the hole which each has a level | step difference in these (for example, the thing of the form currently disclosed by special table 2004-5037883). Furthermore, a cylindrical through hole is provided in the second substrate, a step is formed on the inner side of the through hole, and a cylindrical conductive member is press-fitted on the outer side. A mechanism similar to the socket may be realized.

  FIG. 3 is a diagram showing a state in which the probe unit 100 shown in FIG. 2 is in contact with a pad 310 formed on the substrate 300.

  FIG. 4 is a diagram illustrating a state in which the probe unit 100 illustrated in FIG. 2 is in contact with the solder 210 formed on the substrate 200.

  When inspecting the package substrate 200, first, the tip of the plunger 135 of the probe unit 100 and the pad 310 formed on the counter substrate 300 are aligned. When the probe unit 100 is pressed against the pad 310 in this state, as shown in FIG. 3, the spring 134 having a relatively small spring constant contracts, and the plunger 135 is accommodated in the barrel 133.

  As described above, when the tip of the plunger 135 is pressed against the pad 310, the spring 134 having a relatively small spring constant is contracted, but the spring 132 having a relatively small spring constant is not contracted. Therefore, the counter substrate 300 or the pad 310 can be prevented from being deformed by the pressing force, and the counter substrate 300 is made thicker than necessary to prevent the counter substrate 300 from being deformed. There is no need to increase it.

  Next, the tip of the plunger 131 of the probe unit 100 and the solder 210 on the package substrate 200 are aligned. In this state, when the package substrate 200 is pressed against the solder 210, as shown in FIG. 4, the spring 132 having a relatively large spring constant contracts, and the column portion 131b of the plunger 131 is accommodated in the through hole 122a. It will be.

  Here, the probe unit 100 according to the present embodiment can apply different pressing forces to the solder 210 and the pad 310 by using two springs 132 and 134. Specifically, a spring 132 having a spring constant is selected so that the pressing force against the solder 210 is a pressing force required at the time of inspection (several tens of g, for example, 30 g to 60 g), and the pressing force against the pad 310 is The spring 134 having a spring constant of about 5 to 15 g, which is generally preferable, is selected.

  Moreover, the probe unit of this embodiment takes a measure against a large current by forming a new current path by a shunt current in addition to a single spring and barrel.

  First, since the two springs 132 and 134 are used, the current path can be increased in that current can be passed through both the springs 132 and 134.

  Second, the conductive portion 123 is used as a new current path by forming the conductive portion 123 on the inner wall of the through hole 122a, which is a portion other than the probe pin. This point will be supplemented.

  Please refer to FIG. 4 once again. At point A shown in FIG. 4, the conductive portion 123 and the flange 131 c of the plunger 131 are in contact with each other. At point B shown in FIG. 4, the conductive portion 123 and the spring 132 are in contact with each other. At point C shown in FIG. 4, the conductive portion 123 and the lower taper of the pavel 133 are in contact. It should be noted that the notation of points A to C is for the convenience of description of the drawings, and the contact is not point-like, but actually the contact is planar or linear. I want.

  Thus, typically, a current path including the conductive portion 123 is formed, such as the solder 210 to the flange portion 131c to the point A to the conductive portion 123 to the round 124 to the pad 310. In this embodiment, in order to secure as many new current paths as possible or to easily form the conductive portion 123, the conductive portion 123 is formed in the entire through hole 122a. The conductive portion 123 may be formed only in the region between the points B, only in the region between the points A and C, or only in the region between the points B and C.

(Embodiment 2)
FIG. 5 is a schematic configuration diagram of the probe pin 130 used in the probe unit according to the second embodiment of the present invention. A probe pin 130 shown in FIG. 5 is a modification of the one shown in FIG. In FIG. 5, the same parts as those shown in FIG.

  As shown in FIG. 5, the probe pin 130 of the present embodiment causes the plunger 131 to also function as the barrel 133. That is, in the plunger 131 shown in FIG. 5, the spring 132 contracts when it is brought into contact with the solder 210, and in addition to having the function of the plunger itself, a part of the plunger 135 and the spring 134 that receives this part. And has a function of the barrel 133.

  As described above, the probe pin 130 according to the present embodiment uses the two springs 132 and 134 having different spring constants even if the ranger 131 has the function of the barrel 133, and therefore, is the same as that of the first embodiment. There is an effect.

  In summary, according to the probe pin 130 of each embodiment of the present invention, the package substrate 200 and the counter substrate 300 are required respectively using two springs 132 and 134 having different spring constants. A pressing force can be applied.

  In addition, since the probe pin 130 of this embodiment uses two springs 132 and 134, the current between the package substrate 200 and the counter substrate 300 is higher than that of a probe pin using only a single spring. The route can be increased.

  Furthermore, according to the socket 120 of the present embodiment, since the conductive portion 123 is formed in the through hole in which each of the probe pins is accommodated, the current path between the package substrate 200 and the counter substrate 300 can be increased. it can.

Claims (3)

A hole in which a step for receiving a part of the probe pin is formed;
A conductive body located in a manner in contact with at least two points of the probe pin among the inner walls of the hole;
An IC socket comprising:   The IC socket according to claim 1, wherein the hole is formed with a step for receiving one end of a spring constituting the probe pin. An IC socket according to claim 1;
A probe pin housed in the hole;
A probe system comprising:

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