Electrostatic capacitance measuring device and electrostatic capacitance measuring method

Abstract

To provide an electrostatic capacitance measuring device capable of reducing floating capacitance generated at a tip part of a probe to measure electrostatic capacitance of a measurement target object at high accuracy.SOLUTION: An electrostatic capacitance measuring device 1 includes: a pair of probes 10 extending in a longitudinal direction and arranged in nearly parallel with each other; an electrostatic capacitance measuring instrument connected to the pair of probes 10; a planar shield plate 20 having a first main surface 20a and a second main surface 20b opposed to each other extending in a direction parallel to an extending direction of the pair of probes 10 and placed so that the first main surface 20a and the second main surface 20b are interposed between the pair of probes 10; and insulating layers 30 each provided in the first main surface 20a and the second main surface 20b of the shield plate 20. In the electrostatic capacitance measuring device 1, when viewed in a direction that the pair of probes 10 overlap with each other, the shield plate 20 is arranged at any position overlapping with the pair of probes 10.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a capacitance measuring device and a capacitance measuring method. [Background technology]

[0002] In recent years, the amount of data transmitted by communication devices has increased, and capacitors are now being used in the high frequency range. In particular, there is a demand for high accuracy in capacitance measurement in order to reduce the variation in capacitance.

[0003] As a method for measuring electrostatic capacitance, for example, Patent Document 1 discloses a method in which a probe and an insulating layer are disposed between the probes. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2004-144663 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the measurement method disclosed in Patent Document 1 has a problem in that stray capacitance occurs at the tip of the probe, making it impossible to measure the capacitance of the object to be measured with high accuracy.

[0006] The present invention has been made to solve the above problems, and aims to provide a capacitance measuring device that can reduce the stray capacitance generated at the tip of the probe and measure the capacitance of the object to be measured with high accuracy. [Means for solving the problem]

[0007] The capacitance measuring device of the present invention is a capacitance measuring device comprising: a pair of probes extending in the longitudinal direction and arranged substantially parallel to each other; a capacitance measuring instrument connected to the pair of probes; a flat shield plate having a first main surface and a second main surface facing each other, the extending direction of which is parallel to the extending direction of the pair of probes, the first main surface and the second main surface being sandwiched between the pair of probes; and insulating layers provided on the first main surface and the second main surface of the shield plate, respectively, wherein the shield plate is arranged at all positions where it overlaps with the pair of probes when viewed from the direction in which the pair of probes overlap each other. Effect of the Invention

[0008] According to the present invention, it is possible to provide a capacitance measuring device that can reduce stray capacitance generated at the tip of the probe and measure the capacitance of an object to be measured with high accuracy. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram illustrating an example of a capacitance measuring device of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Diagram 3] FIG. 3 is a perspective view showing a schematic relationship between a shield plate and a pair of probes in the capacitance measuring device shown in FIG. [Figure 4] FIG. 4 is a perspective view that illustrates a schematic diagram of another example of the capacitance measuring device of the present invention. [Diagram 5] FIG. 5 is a side view showing an example of a capacitance measuring method using the capacitance measuring device shown in FIG. [Figure 6] FIG. 6 is a diagram showing a schematic diagram of a state in which a pair of probes is brought into contact with a pair of external electrodes in the capacitance measuring device shown in FIG. [Figure 7] FIG. 7 is a perspective view showing a schematic relationship between a shield plate and a pair of probes in still another example of a capacitance measuring device of the present invention. [Figure 8]FIG. 8 is a side view that illustrates a schematic example of a method for measuring the capacitance of a multilayer ceramic capacitor using the capacitance measuring device shown in FIG. [Figure 9] FIG. 9 is a diagram showing a schematic diagram of a state in which a pair of probes is brought close to a multilayer ceramic capacitor in the capacitance measuring device shown in FIG. [Figure 10] FIG. 10 is a diagram showing a schematic diagram of a state in which a pair of probes is driven toward the multilayer ceramic capacitor by a probe driving mechanism in the capacitance measuring device shown in FIG. [Figure 11] FIG. 11 is a top view diagrammatically illustrating still another example of the capacitance measuring device of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The capacitance measuring device of the present invention will be described below. However, the present invention is not limited to the following configuration, and can be modified as appropriate within the scope of the present invention. Note that the present invention also includes a combination of two or more of the individual preferable configurations of the present invention described below.

[0011] In this specification, terms indicating the relationship between elements (e.g., "opposite," "orthogonal," etc.) and terms indicating the shape of an element (e.g., "rectangular prism") are not intended to be used in a strict sense, but are intended to include a substantially equal range, for example, a difference of a few percent.

[0012] The drawings shown below are schematic diagrams, and the dimensions, aspect ratios, and other scales may differ from those of the actual products.

[0013] [Capacitance measuring device] The capacitance measuring device of the present invention is a capacitance measuring device comprising: a pair of probes extending in the longitudinal direction and arranged approximately parallel to each other; a capacitance measuring instrument connected to the pair of probes; a shield plate which is flat and has a first main surface and a second main surface facing each other, the extending direction of which is parallel to the extending direction of the pair of probes, and is arranged so that the first main surface and the second main surface are sandwiched between the pair of probes; and insulating layers provided on the first main surface and the second main surface of the shield plate, respectively, and is characterized in that the shield plate is arranged at all positions where it overlaps with the pair of probes when viewed from the direction in which the pair of probes overlap each other.

[0014] FIG. 1 is a diagram illustrating an example of a capacitance measuring device of the present invention. The capacitance measuring device 1 shown in FIG. 1 includes a pair of probes 10, a capacitance measuring instrument (not shown) connected to the pair of probes, a shield plate 20, and an insulating layer 30. The pair of probes 10 includes a first probe 11 and a second probe 12 that extend in the longitudinal direction (Y direction shown in FIG. 1) and are arranged substantially parallel to each other.

[0015] The shield plate 20 is in the form of a flat plate having a first main surface 20a and a second main surface 20b opposed to each other. The first main surface 20a and the second main surface 20b of the shield plate 20 are both parallel to a plane (XY plane) parallel to the X direction and the Y direction shown in Fig. 1. Therefore, the direction in which the first main surface 20a and the second main surface 20b of the shield plate 20 extend is parallel to the direction in which the pair of probes 10 extend (Y direction). The shield plate 20 is disposed between the pair of probes 10 such that the first main surface 20a and the second main surface 20b are sandwiched between the pair of probes 10.

[0016] "The first and second main surfaces are sandwiched between a pair of probes" means that the first and second main surfaces of the shield plate are sandwiched between the pair of probes so that they face the probes. In this state, when the pair of probes and the shield plate are viewed from the direction in which the probes extend, the direction connecting the pair of probes is approximately perpendicular to the direction in which the first and second main surfaces of the shield plate extend.

[0017] FIG. 2 is a cross-sectional view taken along line AA in FIG. 2, a first main surface 20a of the shield plate 20 faces a first probe 11 constituting a pair of probes 10. A second main surface 20b of the shield plate 20 faces a second probe 12 constituting a pair of probes 10. The direction (Z direction) connecting the first probe 11 and the second probe 12 constituting the pair of probes 10 is approximately perpendicular to the direction in which the first main surface 20a and the second main surface 20b of the shield plate 20 extend (XY plane).

[0018] The insulating layer 30 is provided on each of the first main surface 20a and the second main surface 20b of the shield plate 20. The insulating layer 30 provided on the first main surface 20a of the shield plate 20 is a first insulating layer 31, and the insulating layer 30 provided on the second main surface 20b of the shield plate 20 is a second insulating layer 32. The shield plate 20 has its first principal surface 20a and second principal surface 20b covered with the insulating layers 30, and therefore can be said to be sandwiched between the insulating layers 30. The first insulating layer 31 and the second insulating layer 32 are collectively referred to as a pair of insulating layers.

[0019] FIG. 3 is a perspective view showing a schematic relationship between a shield plate and a pair of probes in the capacitance measuring device shown in FIG. As shown in FIG. 3, when viewed from the direction in which the first probe 11 and the second probe 12 constituting the pair of probes 10 overlap each other (Z direction), shield plates 20 are arranged at all positions that overlap the pair of probes 10.

[0020] In FIG. 3, a projection view of the first probe 11 and a projection view of the second probe 12 are shown in an area indicated by 10A. In the Y direction, the tip 10a of the projection 10A coincides with the tip 20c of the +Y direction side of the shield plate 20. Therefore, the projections 10A of the first probe 11 and the second probe 12 are all disposed on the shield plate 20 and do not protrude from the shield plate 20. The tip 20c of the side surface of the shield plate 20 in the +Y direction is also referred to as the tip of the shield plate 20.

[0021] 3, the tip 11a of the first probe 11, the tip 12a of the second probe 12, and the tip 20c of the shield plate 20 are on the same ZX plane. That is, in the Y direction, the tip 11a of the first probe 11, the tip 12a of the second probe 12, and the tip 20c of the shield plate 20 are flush with each other. The tip of the first probe and the tip of the second probe are collectively referred to simply as the tip of the probe.

[0022] As shown in Figure 3, in the capacitance measuring device of the present invention, when viewed from the direction in which the pair of probes overlap, shield plates are arranged at all positions where the pair of probes overlap, thereby reducing the stray capacitance generated at the tips of the probes and enabling the capacitance of the object to be measured to be measured with high accuracy.

[0023] (probe) The probe preferably comprises a conductor. The conductor constituting the probe may be, for example, copper or an alloy containing copper, etc. Alternatively, ultra-hard steel may be used.

[0024] The probe has a rod shape extending in the longitudinal direction.

[0025] One end of the probe is connected to a capacitance measuring device. The other end of the probe is the portion that comes into contact with the object to be measured, such as a multilayer ceramic capacitor, and is also called the tip of the probe.

[0026] The diameter of the probe is not particularly limited, but is preferably 30 μm or more and 260 μm or less. However, it is more preferable to adjust the diameter of the probe in accordance with the size of the multilayer ceramic capacitor that is the object to be measured.

[0027] When the size of the multilayer ceramic capacitor to be measured is approximately 0.6 mm in length and approximately 0.3 mm in width and thickness, the diameter of the probe is preferably 140 μm or more and 260 μm or less.

[0028] When the size of the multilayer ceramic capacitor to be measured is approximately 0.4 mm in length and approximately 0.2 mm in width and thickness, the diameter of the probe is preferably 60 μm or more and 100 μm or less.

[0029] When the size of the multilayer ceramic capacitor to be measured is approximately 0.2 mm in length and approximately 0.1 mm in width and thickness, the probe diameter is preferably 30 μm or more and 90 μm or less.

[0030] When the size of the multilayer ceramic capacitor to be measured is approximately 0.1 mm in length and approximately 0.05 mm in width and thickness, the probe diameter is preferably 30 μm or more and 60 μm or less.

[0031] In this specification, the "diameter of the probe" means the diameter of the probe other than the end portion. When the probe has a non-circular shape such as a prism shape, the diameter of the probe is defined as the diameter equivalent to the area of ​​the cut surface when the probe is cut in a plane parallel to a plane perpendicular to the extension direction of the probe.

[0032] The shape of the tip of the probe is not particularly limited, but it is preferable that the tip has a protruding shape like a cone. The shape of the pyramid may be a pyramid such as a triangular pyramid, a square pyramid, a hexagonal pyramid, or a circular cone. The pyramid may also be a frustum with the tip portion removed. The tip shape of the probe may be star-shaped or may be similar in shape to the tip of a flat-head screwdriver when viewed from the extension direction of the probe.

[0033] Regardless of the diameter of the probe, the tip diameter of the probe is preferably 1 μm or more and 10 μm or less, more preferably 3 μm or more and 7 μm or less, and further preferably 5 μm.

[0034] The tip diameter of the probe can be determined as the diameter of a circle equivalent to the area of ​​the tip-most portion of the probe that overlaps with a plane perpendicular to the extension direction of the probe. For example, when the tip shape of the probe is a frustum and the upper base of the frustum is perpendicular to the direction in which the probe extends, the diameter of a circle equivalent to the area of ​​the upper base is defined as the tip diameter of the probe.

[0035] The capacitance measuring device of the present invention may include two pairs of probes. In this case, it is preferable that a shield plate is disposed between each pair of probes for each of the two "pairs of probes."

[0036] In this case, it is preferable that the two unpaired probes arranged on the same side of the shield plate have the same polarity. If the two unpaired probes have the same polarity, stray capacitance is unlikely to occur between the two probes, and therefore the measurement accuracy of the capacitance is unlikely to decrease.

[0037] The probe may be surrounded by a cylindrical insulator or the like, if necessary.

[0038] (Shield plate) The material forming the shield plate may be any conductive material. The conductor constituting the shield plate may be, for example, copper. The shield plate preferably contains copper as a main component.

[0039] The thickness of the shield plate is not particularly limited, but is preferably, for example, 0.01 mm or more and 0.5 mm or less.

[0040] It is preferable that the tip of the shield plate protrudes beyond the tip of the probe. The tip of the shield plate means the end of the shield plate in the direction in which the probe extends.

[0041] The shield plate is preferably grounded or connected to a ground electrode so as to be capacitively coupled thereto.

[0042] (insulating layer) Examples of materials constituting the insulating layer include insulating materials such as a resist film and resin.

[0043] The thickness of the insulating layer is not particularly limited, but may be 0.4 μm or more and 30 μm or less.

[0044] The insulating layer does not have to cover the entire first main surface and the entire second main surface of the shield plate. In other words, the first and second main surfaces of the shield plate may have portions that are not covered with the insulating layer.

[0045] The insulating layer may cover the side surfaces of the shield plate, but it is preferable that the tip of the shield plate is not covered with the insulating layer.

[0046] (Capacitance Meter) The pair of probes is connected to a capacitance measuring device. The method for connecting the pair of probes and the capacitance measuring device is not particularly limited, but may be, for example, connected via lead wires.

[0047] It is preferable that the capacitance measuring instrument performs various corrections such as STD correction, OPEN correction, and short correction before measuring the capacitance.

[0048] (Probe drive mechanism) The capacitance measuring device of the present invention may further include a probe driving mechanism that moves the tips of the pair of probes in the longitudinal direction. However, the range in which the pair of probes can move is limited to a range in which the shield plates are disposed at all positions that overlap the pair of probes when viewed from the direction in which the pair of probes overlap each other.

[0049] (Shield plate drive mechanism) The capacitance measuring device of the present invention may further include a shield plate driving mechanism that moves the shield plate along the longitudinal direction. However, the range in which the shield plate can move is limited to the range in which the shield plate is disposed at all positions where it overlaps with the pair of probes when viewed from the direction in which the pair of probes overlap each other.

[0050] The probe driving mechanism and the shield plate driving mechanism may be used in combination.

[0051] (Transport table) The capacitance measuring device of the present invention may have a transport table for transporting the measurement object.

[0052] The conveyor table is preferably made of an insulating material such as ceramic.

[0053] The conveying table may be provided with holes for passing the probe and the shield plate.

[0054] The conveying table may be provided with a holding mechanism for fixing (holding) the measurement object when measuring the capacitance. The method for fixing the measurement object by the holding mechanism is not particularly limited, and the measurement object may be fixed by means of vacuum suction or the like, or may be fixed by gripping the measurement object. The object to be measured may also be fixed by accommodating it in a recess capable of accommodating a part or the whole of the object to be measured.

[0055] [Capacitance measurement method] The capacitance measurement method of the present invention is a capacitance measurement method for measuring the capacitance of a multilayer ceramic capacitor using the capacitance measurement device of the present invention, characterized in that the multilayer ceramic capacitor has a substantially rectangular parallelepiped element body having two main surfaces facing each other in the stacking direction, two end faces facing each other in a longitudinal direction perpendicular to the stacking direction, and two side surfaces facing each other in a width direction perpendicular to the stacking direction and the longitudinal direction, and external electrodes formed on the two end faces, respectively, and the capacitance is measured by abutting the pair of probes against the pair of external electrodes.

[0056] FIG. 4 is a perspective view that illustrates a schematic diagram of another example of the capacitance measuring device of the present invention. FIG. 4 also shows an example of a capacitance measuring method of the present invention, in which the capacitance of the multilayer ceramic capacitor 100 is measured using the capacitance measuring device 2 which is the capacitance measuring device of the present invention. The capacitance measuring device 2 is the same as the capacitance measuring device 1 described above, except that it further includes a transport table 110.

[0057] The multilayer ceramic capacitor 100 is transported along a transport table 110 . A conveying table 110 on a conveying path for the multilayer ceramic capacitor 100 is provided with holes 110a, 110b, and 110c. Hole 110a is a hole that allows shield plate 20 sandwiched between insulating layers 30 to pass through. The holes 110b and 110c are holes through which the first probe 11 and the second probe 12 pass, respectively.

[0058] The multilayer ceramic capacitor 100 comprises an element body 101 and a pair of external electrodes 102 and 103 . The element body 101 is a roughly rectangular parallelepiped having two main surfaces (first main surface 101a, second main surface 101b) facing each other in the stacking direction (Y direction), two end surfaces (first end surface 101c, second end surface 101d) facing each other in a longitudinal direction (Z direction) perpendicular to the stacking direction, and two side surfaces (first side surface 101e, second side surface 101f) facing each other in a width direction (X direction) perpendicular to the stacking direction and the longitudinal direction.

[0059] The external electrode 102 is provided so as to cover the first end face 101c of the element body 101 and parts of the adjacent first main face 101a, second main face 101b, first side face 101e, and second side face 101f extending from the first end face 101c across the ridge line. External electrode 103 is provided so as to cover second end face 101d of element body 101 and parts of adjacent first main face 101a, second main face 101b, first side face 101e, and second side face 101f extending from second end face 101d across the ridge line. Therefore, the first main surface 101a, the second main surface 101b, the first side surface 101e, and the second side surface 101f of the element body 101 each have an area where an external electrode 102 is provided, an area where an external electrode 103 is provided, and an area where no external electrode is provided and the surface of the element body 101 is exposed.

[0060] The external electrodes provided on the surfaces of the element body 101 other than the first end surface 101c and the second end surface 101d, i.e., the first main surface 101a, the second main surface 101b, the first side surface 101e, and the second side surface 101f, are also referred to as the folded portion, and the thickness of this folded portion is also referred to as the folded thickness.

[0061] FIG. 5 is a side view showing an example of a capacitance measuring method using the capacitance measuring device shown in FIG. As shown in FIG. 5, below the multilayer ceramic capacitor 100 via a conveyor table 110, a pair of probes 10 constituting the capacitance measuring device 1, and a shield plate 20 sandwiched between insulating layers 30 are arranged. The tip 11a of the first probe 11, the tip 12a of the second probe 12, and the tip 20c of the shield plate 20, which constitute the pair of probes 10, are on the same plane (indicated by the dashed line ZX in FIG. 5). 0The surface lies in the ZX plane passing through the

[0062] FIG. 6 is a diagram showing a schematic diagram of a state in which a pair of probes is brought into contact with a pair of external electrodes in the capacitance measuring device shown in FIG. The state shown in FIG. 6 is a state in which the pair of probes 10 and the shield plate 20 sandwiched between the insulating layers 30 are brought closer to the multilayer ceramic capacitor 100 than the state shown in FIG.

[0063] As shown in FIG. 6, a second probe 12 is in contact with an external electrode 102 of the multilayer ceramic capacitor 100, and a first probe 11 is in contact with an external electrode 103. When the pair of probes 10 contact the external electrodes 103 and 102, respectively, the capacitance of the multilayer ceramic capacitor 100 is measured by a capacitance measuring device (not shown) connected to the first probe 11 and the second probe 12.

[0064] The relationship between the pair of probes 10 and the shield plate 20 in FIG. 6 is similar to that in the capacitance measuring device 1 shown in FIG. 6, it can be said that the shield plates 20 are disposed at all positions overlapping the pair of probes 10 when viewed from the direction in which the pair of probes 10 overlap each other (Z direction). Therefore, the stray capacitance occurring at the tips of the pair of probes can be reduced, and the electrostatic capacitance can be measured with high accuracy.

[0065] In the capacitance measuring method of the present invention, it is preferable that the pair of external electrodes are formed across the ridge portion on at least one of the four faces other than the two end faces, and the capacitance is measured by abutting a pair of probes against the portions of the pair of external electrodes formed across the ridge portion from the two end faces.

[0066] In the multilayer ceramic capacitor 100 shown in Figures 4, 5, and 6, a pair of external electrodes 102, 103 are formed across the ridges on all four faces (first main face 101a, second main face 101b, first side face 101e, second side face 101f) except for two end faces (first end face 101c, second end face 101d). The pair of probes 10 are in contact with the folded portions of the pair of external electrodes 102, 103 that are formed on the first main surface 101a.

[0067] 4, 5 and 6, the probes are brought into contact with the multilayer ceramic capacitor 100 from below the conveyor table 110, but the direction in which the probes are brought into contact with (approach) the multilayer ceramic capacitor is not particularly limited. Therefore, for example, the probe may be brought into contact with the multilayer ceramic capacitor from above or side.

[0068] In the capacitance measuring method of the present invention, when the pair of probes are in contact with the pair of external electrodes, it is preferable that the shield plate protrudes toward the multilayer ceramic capacitor beyond the tips of the pair of probes, and that the distance from the tip of the shield plate to the element body when the pair of probes are in contact is less than the thickness of the external electrodes to which the pair of probes are in contact.

[0069] FIG. 7 is a perspective view showing a schematic relationship between a shield plate and a pair of probes in still another example of a capacitance measuring device of the present invention. The capacitance measuring device 3 shown in FIG. 7 is similar to the capacitance measuring device 2 described above, except that the shield plate 20 protrudes further toward the multilayer ceramic capacitor 100 than the tips of the pair of probes 10.

[0070] In FIG. 7, a projection view of the first probe 11 and a projection view of the second probe 12 are shown in an area indicated by 10B.

[0071] When the first probe 11 constituting the pair of probes 10 is projected onto the shield plate 20 in the Z direction, the entire projection 10B of the first probe 11 is disposed on the shield plate 20 and does not protrude. Similarly, when the second probe 12 constituting the pair of probes 10 is projected onto the shield plate 20 in the Z direction, the entire projection 10B of the second probe 12 is disposed on the shield plate 20 and does not protrude. Therefore, when viewed from the direction in which the first probe 11 and the second probe 12 constituting the pair of probes 10 overlap each other (Z direction in Figure 7), it can be said that the shield plates 20 are arranged at all positions where they overlap the pair of probes 10.

[0072] Furthermore, as shown in FIG. 7, between the tip 10b of the projection 10B of the first probe 11 and the second probe 12 and the tip 20c of the shield plate 20, there is an area where the projection 10B is not arranged.

[0073] The tip 11a of the first probe 11 and the tip 12a of the second probe 12 are in the same ZX plane (indicated by the dashed line ZX in FIG. 7). 2 However, a tip 20 c of the shield plate 20 is not in the same ZX plane as the tip 11 a of the first probe 11 and the tip 12 a of the second probe 12 . The tip 20c of the shield plate 20 is in the ZX plane (dashed line ZX) on which the tips (11a, 12a) of the probe 10 are located. 2 The plane that passes through the ZX axis is in the +Y direction. 1 It lies on the ZX plane passing through.

[0074] Therefore, the tip 10b of the projection 10B does not overlap the tip 20c of the shield plate 20, and it can be said that the tip 20c of the shield plate 20 protrudes in the +Y direction by a predetermined length beyond the tip 10b of the projection 10B.

[0075] FIG. 8 is a side view that illustrates a schematic example of a method for measuring the capacitance of a multilayer ceramic capacitor using the capacitance measuring device shown in FIG. As shown in FIG. 8, a pair of probes 10 and a shield plate 20 constituting a capacitance measuring device 3 are disposed below the multilayer ceramic capacitor 100 via a conveyor table 110. The tip 20c of the shield plate 20 protrudes in the +Y direction by a predetermined length beyond the tips of the pair of probes 10 (first probe 11, second probe 12). At this time, the distance L from the tip 20c of the shield plate 20 to the tips of the probes (11a, 12a) in the Y direction is 1 is also called the shield plate protrusion amount. In this state, the pair of probes 10 and shield plate 20 constituting the capacitance measuring device 3 are brought close to the multilayer ceramic capacitor 100 .

[0076] FIG. 9 is a diagram showing a schematic diagram of a state in which a pair of probes is brought close to a multilayer ceramic capacitor in the capacitance measuring device shown in FIG. The state shown in FIG. 9 is a state in which the pair of probes 10 and the shield plate 20 sandwiched between the insulating layers 30 are brought closer to the multilayer ceramic capacitor 100 than the state shown in FIG.

[0077] When the tip 20c of the shield plate 20 protrudes in the +Y direction further than the tips of the pair of probes, as in the capacitance measuring device 3 shown in Figure 8, even if the pair of probes and the shield plate 20 are brought close to the multilayer ceramic capacitor 100, as shown in Figure 9, the shield plate 20 may come into contact with the element body 101 that constitutes the multilayer ceramic capacitor 100 before the pair of probes 10 come into contact with the external electrodes 102, 103. In addition, the shield plate protrusion amount L in Fig. 9 1 is the shield plate protrusion amount L in Figure 8 before the pair of probes are brought close to each other. 1 is the same as: In this state, the pair of probes 10 cannot be brought into contact with the external electrodes 102 and 103.

[0078] If the capacitance measuring device of the present invention is provided with a probe driving mechanism, it is possible to bring the pair of probes into contact with the external electrodes even in the above-mentioned case.

[0079] FIG. 10 is a diagram showing a schematic diagram of a state in which a pair of probes is driven toward the multilayer ceramic capacitor by a probe driving mechanism in the capacitance measuring device shown in FIG. As shown in FIG. 10, by using a probe driving mechanism (not shown), the pair of probes 10 can be further moved in the +Y direction without changing the position of the shield plate 20, and the pair of probes 10 can be abutted against the external electrodes 102, 103.

[0080] In a state in which the pair of probes 10 are in contact with the external electrodes 102 and 103, the tip 20c of the shield plate 20 protrudes further in the +Y direction than the tips of the pair of probes 10. As shown in FIG. 10, when the pair of probes 10 are in contact with the external electrodes 102, 103 of the multilayer ceramic capacitor 100, the distance L from the tip 20c of the shield plate to the tips (11a, 12a) of the probes in the direction in which the pair of probes 10 extend (Y direction) is 2 is also called the shield plate protrusion amount when the probe comes into contact with the shield plate.

[0081] When the tip 20c of the shield plate 20 protrudes in the +Y direction further than the tips of the pair of probes 10, the electric field that is generated from the tips of the pair of probes 10 and wraps around to the multilayer ceramic capacitor 100 side can be blocked by the shield plate 20. Therefore, compared to the case where the tips 11a, 12a of the pair of probes 10 are flush with the tip 20c of the shield plate 20, the stray capacitance generated at the tips of the probes can be further reduced.

[0082] 10, the tip 20c of the shield plate 20 is in contact with the element body 101 that constitutes the multilayer ceramic capacitor 100. Therefore, the distance from the tip 20c of the shield plate 20 to the element body 101 that constitutes the multilayer ceramic capacitor 100 in the direction in which the pair of probes 10 extend (Y direction) is zero. When the tip 20c of the shield plate 20 is in contact with the element body 101 constituting the multilayer ceramic capacitor 100, the electric field that is generated from the tips of the pair of probes 10 and wraps around to the multilayer ceramic capacitor 100 side can be blocked to the maximum extent by the shield plate 20. Therefore, the stray capacitance generated at the tip portions of the probes can be particularly reduced. At this time, the shield plate protrusion amount L 2 is equal to the folded thickness of the external electrodes 102 and 103 with which the pair of probes 10 are in contact (thickness indicated by t in FIG. 10).

[0083] Here, the folded thickness t of the external electrodes 102, 103 is equal to the sum of the distance from the tips of the pair of probes 10 to the tip 20c of the shield plate 20 (shield plate protrusion amount) when the pair of probes 10 abut against the external electrodes 102, 103, and the distance from the tip 20c of the shield plate 20 to the element body 101. Therefore, if the distance from the tip 20c of the shield plate 20 to the element body 101 when the pair of probes 10 are in contact with the external electrodes 102 and 103 is equal to or less than the folded thickness t of the external electrodes 102 and 103 to which the pair of probes 10 are in contact, the shield plate protrusion amount L 2 However, this is equal to or smaller than the folded thickness t of the external electrodes 102 and 103 with which the pair of probes 10 are in contact.

[0084] The above-mentioned effect is achieved when, when the pair of probes 10 contact the external electrodes 102 and 103, the distance from the tip 20c of the shield plate 20 to the element body 101 is equal to or less than the folded thickness t of the external electrodes 102 and 103 that the pair of probes 10 contact, and the shield plate protrusion amount L 2 However, this effect is exerted so long as the thickness is equal to or less than the folded thickness t of the external electrodes 102 and 103 with which the pair of probes 10 are in contact. Therefore, as described above, it is not always necessary to provide a probe driving mechanism, as will be explained below.

[0085] In the state shown in FIG. 8, before the pair of probes 10 come into contact with the external electrodes 102, 103 of the multilayer ceramic capacitor 100, the shield plate protrusion amount L 1 is larger than the folded thickness t of the external electrodes 102, 103. Therefore, when the pair of probes 10 and the shield plate 20 are moved simultaneously, the shield plate 20 comes into contact with the element body 101 before the pair of probes 10 come into contact with the external electrodes 102, 103. Therefore, it was necessary to reduce the amount of shield plate protrusion by using a probe driving mechanism to move the pair of probes 10 in the +Y direction while keeping the shield plate 20 fixed.

[0086] In contrast, in the state shown in FIG. 8, the shield plate protrusion amount L 1 is equal to or less than the folded thickness t of the external electrodes 102 and 103, for example, the shield plate protrusion amount L 1 Not L 2 If this is the case, the state shown in Fig. 10 will be reached without passing through the state shown in Fig. 9. Therefore, no probe drive mechanism is required.

[0087] In addition, the amount of protrusion of the shield plate when the probe is in contact is preferably equal to or less than the thickness of the folded portion of the external electrode against which the probe is in contact, or more preferably equal to the thickness of the folded portion of the external electrode against which the probe is in contact. In other words, the distance from the tip of the shield plate to the element body when the probe is in contact is preferably equal to or less than the thickness of the folded portion of the external electrode against which the probe is in contact, or more preferably zero.

[0088] FIG. 11 is a top view diagrammatically illustrating still another example of the capacitance measuring device of the present invention. The capacitance measuring device 4 shown in FIG. 11 has a part feeder 120, a linear feeder 130, a conveying table 110, a measurement area 150 provided on the conveying table 110, a first discharge area 160, and a second discharge area 170. The conveyor table 110 has recesses 140, into which the multilayer ceramic capacitors 100 can be fitted, provided at equal intervals along the circumference.

[0089] The stored multilayer ceramic capacitors 100 are successively transported by a parts feeder 120 and a linear feeder 130 so as to fit into recesses 140 on a transport table 110 . The multilayer ceramic capacitors 100 arranged to fit into the recesses 140 are transported one by one to a measurement area 150 by the rotation of the transport table 110 .

[0090] The capacitance of the multilayer ceramic capacitor 100 that has been transported to the measurement area 150 is measured. The method for measuring the capacitance is the same as that of the capacitance measuring device of the present invention described above.

[0091] The multilayer ceramic capacitors 100 may be sorted in the first discharge area 160 and the second discharge area 170 depending on the capacitance measurement result in the measurement area 150 . For example, multilayer ceramic capacitors 100 that have been determined to be defective as a result of capacitance measurement in measurement area 150 may be removed from conveyor table 110 in first discharge area 160. Furthermore, for example, multilayer ceramic capacitors 100 that have been determined to be non-defective as a result of capacitance measurement in measurement area 150 may be transported from transport table 110 in second discharge area 170 to the next line.

[0092] (Multilayer ceramic capacitors) The multilayer ceramic capacitor, the capacitance of which is to be measured by the capacitance measuring device and the capacitance measuring method of the present invention, is a multilayer ceramic capacitor having a pair of external electrodes formed on the end faces.

[0093] The multilayer ceramic capacitor preferably has a substantially rectangular parallelepiped element body having two main surfaces opposing each other in the stacking direction, two end faces opposing each other in a longitudinal direction perpendicular to the stacking direction, and two side faces opposing each other in a width direction perpendicular to the stacking direction and the longitudinal direction, and external electrodes formed on each of the two end faces. When the multilayer ceramic capacitor has the above-described configuration, the capacitance can be measured by contacting a pair of probes constituting the capacitance measuring device of the present invention with a pair of external electrodes of the multilayer ceramic capacitor.

[0094] It is preferable that the pair of external electrodes is also formed across the ridge line on at least one of the four surfaces other than the two end surfaces. When a pair of external electrodes are formed across the ridge portion on at least one of the four surfaces other than the two end faces, the capacitance can be measured by abutting a pair of probes that constitute the capacitance measuring device of the present invention to the portion formed across the ridge portion from the two end faces of the pair of external electrodes.

[0095] The shape of the multilayer ceramic capacitor is, for example, a substantially rectangular parallelepiped shape with a length in the longitudinal direction of about 0.6 mm and lengths in the width direction and lamination direction of about 0.3 mm.

[0096] The multilayer ceramic capacitor may have a generally rectangular parallelepiped shape with a length in the longitudinal direction of about 0.4 mm and lengths in the width direction and lamination direction of about 0.2 mm, for example.

[0097] The multilayer ceramic capacitor may have a generally rectangular parallelepiped shape with a longitudinal length of about 0.2 mm and a width and lamination direction length of about 0.1 mm, for example.

[0098] The shape of the multilayer ceramic capacitor is, for example, a substantially rectangular parallelepiped shape with a length in the longitudinal direction of about 0.1 mm and lengths in the width direction and lamination direction of about 0.05 mm.

[0099] The thickness of the portion of the external electrode formed on the surfaces other than the two end surfaces is also called the folded thickness. The thickness of the folded portion of the external electrode is not particularly limited, but is preferably 10 μm or more and 25 μm or less.

[0100] When the multilayer ceramic capacitor has a generally rectangular parallelepiped shape with a longitudinal length of about 0.6 mm and width and lamination directions of about 0.3 mm, the fold thickness is preferably 15 μm or more and 25 μm or less.

[0101] When the multilayer ceramic capacitor has a generally rectangular parallelepiped shape with a longitudinal length of about 0.4 mm and a width and lamination direction length of about 0.2 mm, the fold thickness is preferably 10 μm or more and 20 μm or less.

[0102] When the multilayer ceramic capacitor has a generally rectangular parallelepiped shape with a longitudinal length of about 0.2 mm and width and lamination directions of about 0.1 mm, the fold thickness is preferably 10 μm or more and 15 μm or less.

[0103] When the multilayer ceramic capacitor has a generally rectangular parallelepiped shape with a longitudinal length of about 0.1 mm and width and lamination directions of about 0.05 mm, the fold thickness is preferably 10 μm or more and 15 μm or less.

[0104] This specification discloses the following inventions.

[0105] The present disclosure (1) provides a pair of probes extending in a longitudinal direction and arranged substantially parallel to each other; a capacitance measuring device connected to the pair of probes; a shield plate having a flat shape, a first main surface and a second main surface facing each other extending in a direction parallel to a direction in which the pair of probes extend, and the first main surface and the second main surface are sandwiched between the pair of probes; an insulating layer provided on each of the first main surface and the second main surface of the shield plate, The capacitance measuring device is characterized in that the shield plate is arranged at all positions that overlap with the pair of probes when viewed from a direction in which the pair of probes overlap each other.

[0106] The present disclosure (2) is the capacitance measuring device according to the present disclosure (1), further comprising a probe driving mechanism that moves the tips of the pair of probes along the longitudinal direction.

[0107] The present disclosure (3) is a capacitance measuring device according to the present disclosure (1) or (2), in which each probe constituting the pair of probes has a diameter of 30 μm or more and 260 μm or less and a tip diameter of 1 μm or more and 10 μm or less.

[0108] The present disclosure (4) is a capacitance measuring method for measuring the capacitance of a multilayer ceramic capacitor using a capacitance measuring device in any combination with any of the present disclosures (1) to (3), The multilayer ceramic capacitor comprises a substantially rectangular parallelepiped element body having two main surfaces opposing each other in a lamination direction, two end faces opposing each other in a longitudinal direction perpendicular to the lamination direction, and two side faces opposing each other in a width direction perpendicular to the lamination direction and the longitudinal direction, and external electrodes formed on each of the two end faces, The capacitance measuring method is characterized in that the pair of probes are brought into contact with the pair of external electrodes to measure the capacitance.

[0109] The present disclosure (5) is a method for manufacturing a semiconductor device according to the present invention, wherein the pair of external electrodes is formed across a ridge line portion on at least one of the four surfaces other than the two end surfaces, This is a capacitance measurement method described in the present disclosure (4), in which the capacitance is measured by contacting the pair of probes with the portion of the pair of external electrodes that is formed across the ridge portion from the two end faces.

[0110] The present disclosure (6) is a method for manufacturing a multilayer ceramic capacitor comprising the steps of: when the pair of probes are in contact with the pair of external electrodes, the shield plate protrudes toward the multilayer ceramic capacitor beyond the tips of the pair of probes; The capacitance measuring method according to the present disclosure (5), wherein the distance from the tip of the shield plate to the element body when the pair of probes are brought into contact with the element body is equal to or less than the thickness of the external electrode. EXAMPLES

[0111] EXAMPLES Hereinafter, examples that more specifically disclose the present invention will be described, however, the present invention is not limited to these examples.

[0112] Example 1 For multilayer ceramic capacitors whose capacitance was accurately known, the capacitance was measured using a capacitance measuring device with a pair of probes and a shield plate in the position shown in Figure 3 (i.e., with the tips of the pair of probes and the tip of the shield plate flush with each other). Since the measured value includes the stray capacitance between the probes, the stray capacitance between the probes can be calculated by subtracting the measured value from the exact capacitance of the multilayer ceramic capacitor. The stray capacitance was calculated by taking the average value of 10 measurements as the measured value, and the value was 0.2 fF.

[0113] The laminated ceramic capacitor used had a length dimension of 0.6 mm and dimensions in the width and lamination directions of 0.3 mm. The multilayer ceramic capacitor had a substantially rectangular parallelepiped element body having two end faces (first end face and second end face) opposing each other in the longitudinal direction, two main faces (first main face and second main face) opposing each other in a stacking direction perpendicular to the longitudinal direction, and two side faces (first side face and second side face) perpendicular to the longitudinal direction and the stacking direction, and external electrodes covering the first end face and second end face of the element body, respectively.

[0114] The external electrodes included a first external electrode formed on the first main surface, the second main surface, the first side surface, and a portion of the second side surface, spanning from the first end face of the element body across the ridge portion, and a second external electrode formed on the first main surface, the second main surface, the first side surface, and a portion of the second side surface, spanning from the second end face of the element body across the ridge portion, and the fold-back thicknesses of the external electrodes formed on the first main surface, the second main surface, the first side surface, and the second side surface were all 30 μm.

[0115] Example 2 The capacitance of the multilayer ceramic capacitor was measured and the stray capacitance between the probes was calculated in the same manner as in Example 1, except that the position of the shield plate in the Y direction was adjusted so that the tip of the shield plate protruded 20 μm beyond the tips of the pair of probes. The value of the stray capacitance was 0.05 fF.

[0116] Comparative Example 1 The positions of the pair of probes in the Y direction were adjusted, and the capacitance of the multilayer ceramic capacitor was measured in the same manner as in Example 1, except that no shield plate was provided between the pair of probes, and the stray capacitance between the probes was calculated. The value of the stray capacitance was 8.0 fF.

[0117] From the results of Example 1 and Comparative Example 1, it was found that the use of the capacitance measuring device of the present invention can greatly reduce the stray capacitance generated at the tip of the probe. This confirmed that the use of the capacitance measuring device of the present invention can measure the capacitance of the measurement target with high accuracy.

[0118] From the results of Example 1 and Example 2, it was confirmed that the stray capacitance could be further reduced by making the end face of the shield plate protrude beyond the tips of the pair of probes. [Explanation of symbols]

[0119] 1, 2, 3, 4 Capacitance measuring device 10 pairs of probes Projection of 10A and 10B probes 10a, 10b Projection of the tip of the probe 11 First probe 11a Tip of the first probe 12 Second probe 12a Tip of the second probe 20 Shield plate 20a: First main surface of shield plate 20b Second main surface of shield plate 20c Tip of the shield plate (side of the shield plate in the +Y direction) 30 Insulating layer 31 First insulating layer 32 Second insulating layer 100 Multilayer ceramic capacitors 101 Base 101a: First main surface of element 101b: second main surface of the body 101c: first end surface of element 101d: second end face of element 101e First side of the body 101f Second side of the body 102, 103 External electrode 110 Transport table 110a, 110b, 110c holes 120 Parts Feeder 130 Linear Feeder 140 Recess 150 measurement area 160 First Discharge Area 170 Second Discharge Area t Thickness of folded outer electrode L 1 Shield plate protrusion amount L 2 Shield plate protrusion amount when probe is in contact

Claims

1. A pair of probes extending in a longitudinal direction and arranged substantially parallel to each other; a capacitance measuring device connected to the pair of probes; a shield plate having a flat shape, a first main surface and a second main surface facing each other extending in a direction parallel to a direction in which the pair of probes extend, and the first main surface and the second main surface are sandwiched between the pair of probes; an insulating layer provided on each of the first main surface and the second main surface of the shield plate, 13. A capacitance measuring device, comprising: a shield plate disposed at all positions that overlap with the pair of probes when viewed from a direction in which the pair of probes overlap each other;

2. The capacitance measuring device according to claim 1 , further comprising a probe driving mechanism that moves the tips of the pair of probes along the longitudinal direction.

3. 2. The capacitance measuring device according to claim 1, wherein each of the pair of probes has a diameter of 30 μm or more and 260 μm or less and a tip diameter of 1 μm or more and 10 μm or less.

4. A capacitance measuring method for measuring the capacitance of a multilayer ceramic capacitor using the capacitance measuring device according to any one of claims 1 to 3, comprising the steps of: The multilayer ceramic capacitor comprises a substantially rectangular parallelepiped element body having two main surfaces opposing each other in a lamination direction, two end faces opposing each other in a longitudinal direction perpendicular to the lamination direction, and two side faces opposing each other in a width direction perpendicular to the lamination direction and the longitudinal direction, and external electrodes formed on the two end faces, respectively; A capacitance measuring method, comprising: measuring a capacitance by bringing the pair of probes into contact with the pair of external electrodes.

5. the pair of external electrodes are formed across a ridge line portion on at least one of the four surfaces other than the two end surfaces, 5. The capacitance measuring method according to claim 4, wherein the capacitance is measured by contacting the pair of probes with portions of the pair of external electrodes that are formed across ridges from the two end faces.

6. when the pair of probes are in contact with the pair of external electrodes, the shield plate protrudes toward the multilayer ceramic capacitor beyond the tips of the pair of probes, 6. The capacitance measuring method according to claim 5, wherein a distance from the tip of the shield plate to the element body when the pair of probes are in contact with the element body is equal to or smaller than a thickness of the external electrode.

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