JP2012181045A - Vertical probe needle and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vertical probe needle and manufacturing method therefore capable of preventing the deterioration of contact stability with respect to an inspection object and attaining repetitive usage in a long time.SOLUTION: A vertical probe needle is constituted by a metallic wire 1 with the wire diameter of 0.02-0.04 mm and the length of 3.0-6.0 mm, where a trunk part 1b is coated by an insulation coating membrane 2 of SiOand a metallic coating membrane 3 having granular protrusions 3a is formed at a distal end 1a. An end edge 2a of the insulation coating membrane 2 is separated by 20-60 μm from an apex part 5, and also the apex part 5 is formed to have a circular arc shape with the curvature radius of 26-45 μm in a longitudinal section view.

Description

  The present invention relates to a probe needle used for a probe card and a manufacturing method thereof, and more particularly to a vertical probe needle installed on a probe card so as to be substantially perpendicular to an inspection object and a manufacturing method thereof.

  There are two types of probe needles used in a probe card: a cantilever type arranged substantially parallel to an inspection object such as a wafer (IC chip) and a vertical type arranged substantially vertically. The cantilever type probe needle has a structure in which a distal end portion is bent in a substantially L shape and a proximal end portion is supported by a probe card body. On the other hand, the vertical probe needle is linear and can be installed on the probe card at a higher density than the cantilever probe needle.

Here, the installation state of the vertical probe needle in the probe card will be described with reference to FIG. 12 (a) and 12 (b) are schematic diagrams showing the structure of a probe card provided with a conventional vertical probe needle. In FIG. 12B, unlike FIG. 12A, an insulating coating is applied to the side surface of the vertical probe needle.
As shown in FIG. 12 (a), the vertical probe needle 51 used in the probe card is made of a thin metal wire having high elasticity such as tungsten, rhenium tungsten, beryllium copper, copper silver alloy, and the like. It is slidably supported by support plates 52a and 52b arranged in parallel to each other. Further, the base end portion 51a of the vertical probe needle 51 is electrically connected to a conductor wiring pattern (not shown) formed on the probe card main body (not shown).

  When conducting an energization inspection of the wafer 54 using such a probe card, first, the probe card is arranged slightly apart from the wafer 54 so that the tip 51b of the vertical probe needle 51 does not contact the electrode 55. Next, after the electrode 55 is slid and brought into contact with the tip 51b of the front vertical probe needle 51, the probe card is brought closer to the wafer 54 by a predetermined distance in order to increase the contact pressure. As a result, as shown in FIG. 12B, the vertical probe needle 51 bends between the support plates 52a and 52b. At this time, an insulating coating 53 is usually provided on the side surface of the vertical probe needle 51 so that adjacent ones do not come into contact with each other and are short-circuited.

In general, an oxide film or the like is easily formed on the surface of the electrode 55 of the wafer 54. In a probe card equipped with a cantilever type probe needle, the oxide film is scraped off at the tip of the probe needle during an energization inspection. On the other hand, when conducting the energization inspection with the probe card shown in FIG. 12, the tip 51b of the vertical probe needle 51 is only pressed perpendicularly to the electrode 55, and the oxide film is scraped off with the probe needle. There is no. Therefore, when the oxide film is not pierced by the tip portion of the probe needle, the contact resistance value becomes high, and an accurate energization inspection becomes difficult.
In order to cope with such problems, in recent years, active research and development have been conducted on probe cards having vertical probe needles. In connection with this, several inventions and devices have already been disclosed.

For example, Patent Document 1 discloses an invention relating to a “vertical coil spring probe” that can ensure a desired contact load and can be used repeatedly several hundred thousand times.
In the invention disclosed in Patent Document 1, the guide tube is connected to the upper end of the lower probe pin that contacts the conductive pad of the measurement object, and the guide shaft portion of the upper probe pin connected to the conductive pattern of the probe card is compressed. In addition to being inserted into the coil spring, its tip is inserted into the guide tube, and a compression coil spring is externally inserted into the guide shaft portion.
In the probe having such a structure, a high contact pressure is secured by the elastic force of the compression coil spring. Further, since the guide shaft portion which is a part of the upper probe pin is inserted into the compression coil spring, the compression coil spring is not displaced outward during overdrive. Therefore, unlike the conventional probe, there is no possibility of contact between adjacent probes without storing the compression coil spring in the cylinder. As a result, the probes can be arranged at a desired narrow pitch.

In Patent Document 2, a probe having a name “probe and probe manufacturing method”, in which a plurality of protrusions are formed at the tip of the substrate or the like to be inspected and the contact stability with the object to be inspected is improved. An invention related to this is disclosed.
In the probe disclosed in Patent Document 2, a nickel plating layer and a gold plating layer are sequentially formed on the surface of a base material made of beryllium copper or the like, and a plurality of quadrangular pyramidal protrusions are formed at the tip. It is characterized by.
According to the probe having such a structure, the load at the time of contact with the object to be inspected is evenly distributed, so that the progress of wear of the gold plating layer is delayed. Thereby, the contact stability of the probe with respect to the object to be inspected is hardly lowered, and the life of the probe is extended.

JP 2006-208329 A JP 2007-218675 A

  However, in the invention disclosed in Patent Document 1 which is the above-described prior art, the outer diameter of the probe is determined by the outer diameter of the compression coil spring, so that the entire diameter of the probe cannot be reduced. There has been a problem that the arrangement density of can not be increased. There is also a problem that the tip of the probe is easily worn by contact with the measurement object.

  Moreover, in the invention disclosed in Patent Document 2, when the probe has a small diameter, there is a problem that the processing of the tip portion is not easy. The tip of the probe of the present invention is processed by reciprocating linearly while applying a pressing force by bringing a bite having a V-shaped cross section into contact with one end surface of the base material of the probe. Is done. Therefore, the protrusion is formed on a plane orthogonal to the longitudinal direction of the probe. Therefore, when the probe is bent at the time of energization inspection and the entire end surface of the probe on which the plurality of protrusions are formed comes into non-uniform contact with the object to be inspected, the above-described effect may not be exhibited. That is, the present invention is suitable for the spring probe as described in paragraph [0006] of the specification of Patent Document 2, but is applicable to the above-described vertical probe needle described with reference to FIG. There was a problem that it was not possible. In addition, when this invention is applied to a spring probe, it will have the subject similar to the invention described in Patent Document 1.

  The present invention has been made in view of such a conventional situation, and a vertical probe needle that can prevent repeated deterioration of contact stability with respect to an object to be inspected and can be used repeatedly for a long time, and a manufacturing method thereof. The purpose is to provide.

To achieve the above object, a first aspect of the present invention, the vertical probe needles which are arranged so as to form a substantially perpendicular to the inspection target object mounted on the probe card, the body portion is covered with an insulating film of SiO ₂ In addition, a metal film having a plurality of granular protrusions is formed on the tip portion.
In the vertical probe needle having such a structure, the contact pressure with the object to be inspected is approximately uniformly dispersed by the plurality of granular protrusions, so that the contact resistance with respect to the object to be inspected is stabilized and the metal is used even after repeated use. It has the effect that the film is difficult to wear. Further, when used in a probe card, there is no possibility of short circuit even if the body portions of adjacent vertical probe needles contact each other during overdrive. Further, since the metal film is not formed on the body part, the so-called “needle thickening” in which the diameter of the body part increases due to the deposition of the metal film does not occur.

According to a second aspect of the present invention, in the vertical probe needle according to the first aspect, the insulating film is formed such that the edge on the tip end side is located at a distance of 20 to 60 μm from the topmost portion of the tip end portion. It is characterized by that.
In the vertical probe needle having such a structure, since the metal film is formed over 20 μm or more from the top toward the edge of the insulating film, it has the effect that the granular protrusions are difficult to peel off even when used repeatedly. Further, since the metal film is not formed more than 60 μm from the top toward the edge of the insulating film, there is an effect that granular protrusions having a uniform particle diameter are formed.

According to a third aspect of the present invention, in the vertical probe needle according to the first or second aspect, the topmost portion of the tip is formed in an arc shape having a radius of curvature of 26 to 45 μm as viewed in a longitudinal section. It is characterized by that.
In the vertical probe needle having such a structure, the radius of curvature when the topmost portion of the tip portion is viewed in a longitudinal section is 26 μm or more, and therefore metal ions are deposited when the metal film is formed by electroplating. It has the effect that it is difficult to concentrate on the center of the. In addition, since the radius of curvature when the topmost portion of the tip portion is viewed in a longitudinal section is 45 μm or less, it is difficult for metal ion precipitation to concentrate on the corners of the topmost portion when forming a metal film by electroplating. Have

According to a fourth aspect of the present invention, there is provided a vertical probe needle manufacturing method comprising: forming a SiO ₂ insulating film so as to cover a body of a fine metal wire; and nickel, copper, silver, gold, zinc, lead Immersing in a plating solution using at least one metal body of platinum, palladium, and an alloy containing these as an anode and a fine metal wire as a cathode, and applying a pulse waveform current between the cathode and anode; , And a metal film having a plurality of granular protrusions is formed at the tip of the thin metal wire.
According to such a method for manufacturing a vertical probe needle, the decrease and recovery of the metal ion concentration are successively repeated around the fine metal wire in the plating solution, so that a large current is instantaneously applied to the fine metal wire intermittently. Applied. As a result, a metal film having a plurality of granular protrusions is formed at the tip of the fine metal wire. Moreover, it has the effect | action that the area | region in which a metal film is formed is restrict | limited by an insulating film.

According to a fifth aspect of the present invention, in the method for manufacturing a vertical probe needle according to the fourth aspect, the insulating film is formed such that the edge on the tip side is located at a distance of 20 to 60 μm from the topmost part of the tip. It is characterized by that.
The invention described in the present claim has the same effect as the invention described in the second aspect since the invention of the object described in the second aspect is regarded as a method invention.

According to a sixth aspect of the present invention, in the method for manufacturing the vertical probe needle according to the fourth or fifth aspect, before the metal thin wire is immersed in the plating solution, the topmost portion of the tip portion is viewed in a longitudinal section. The method includes a step of processing into an arc shape having a radius of curvature of 26 to 45 μm.
The invention according to the present invention has the same effect as that of the invention according to the third aspect since the invention according to the third aspect is regarded as a method invention.

  According to the vertical probe needle of the first aspect of the present invention, the oxide film formed on the surface of the inspection object can be easily pierced at the tip portion. Thereby, inspection accuracy improves. Moreover, this high inspection accuracy can be maintained for a long time. Furthermore, since the vertical probe needles having a narrow body diameter can be manufactured, when a large number of vertical probe needles are attached to the probe card, the arrangement density can be increased.

  In addition, according to the vertical probe needle of the second aspect of the present invention, the effect of the first aspect of the present invention that can maintain high inspection accuracy for a long time is further exhibited.

  According to the vertical probe needle of the third aspect of the present invention, a clean substantially spherical granular projection having a uniform particle diameter is formed substantially uniformly on the surface of the tip portion. The effect of the invention is further exhibited.

  According to the method for manufacturing a vertical probe needle according to claim 4 of the present invention, the vertical probe needle according to the invention according to claim 1 can be easily manufactured. In that case, since it is not necessary to use a large-scale manufacturing facility, manufacturing cost can be reduced. Moreover, it is possible to easily adjust the region where the metal film is deposited by changing the region where the insulating film is deposited on the side surface of the thin metal wire.

  According to the method for manufacturing a vertical probe needle of claim 5 of the present invention, in addition to the effect of the invention of claim 4, the effect of being able to manufacture the vertical probe needle of the invention of claim 2 at low cost. Play.

  According to the method for producing a vertical probe needle of claim 6 of the present invention, in addition to the effect of the invention of claim 4 or 5, the vertical probe needle of the invention of claim 3 is inexpensive. There is an effect that it can be manufactured.

(A) is a schematic diagram which shows the external appearance of the Example of the vertical type probe needle which concerns on embodiment of this invention, (b) is the figure which expanded the front-end | tip part of the same figure (a). (A) And (b) is an output figure of the laser micrograph of the front-end | tip part before a contact test in the Example of the vertical probe needle | hook which concerns on embodiment of this invention, and a three-dimensional shape measurement result, respectively (c) Is a graph showing the results of the contact test. (A) And (b) is the laser micrograph of the front-end | tip part before the contact test in a conventional vertical type probe needle, and the output figure of a three-dimensional shape measurement result, respectively, (c) is a graph which shows the result of the contact test It is. (A) thru | or (c) are the laser microscope photographs of the front-end | tip part before the contact test of the vertical probe needle which concerns on embodiment of this invention, respectively. (A) And (b) is a laser micrograph of the front-end | tip part after the contact test of the vertical probe needle | hook of FIG.4 (b) and FIG.4 (c), respectively. (A) And (b) is a laser micrograph of the front-end | tip part before and behind the contact test in the vertical probe needle which concerns on embodiment of this invention, respectively, (c) is a graph which shows the result of the contact test. . (A) And (b) is the figure which showed typically the shape of the front-end | tip part of the vertical type probe needle concerning embodiment of this invention, (c) is the output figure of the three-dimensional shape measurement result. . (A) And (b) is the profile figure which shows the laser micrograph and two-dimensional shape of the front-end | tip part of the vertical probe needle which concern on embodiment of this invention, respectively. (A) And (b) is the profile figure which shows the laser micrograph and two-dimensional shape of the front-end | tip part of the vertical probe needle which concern on embodiment of this invention, respectively. (A) And (b) is the profile figure which shows the laser micrograph and two-dimensional shape of the front-end | tip part of the vertical probe needle which concern on embodiment of this invention, respectively. (A) And (b) is the profile figure which shows the laser micrograph and two-dimensional shape of the front-end | tip part of the vertical probe needle which concern on embodiment of this invention, respectively. (A) And (b) is a schematic diagram which shows the structure of the probe card provided with the conventional vertical probe needle.

  With respect to the vertical probe needle of the present invention, its structure, operation and effect will be described using FIGS. 1 to 11 while comparing with the prior art, and its manufacturing method will also be specifically described.

As shown in FIG. 1 (a), the vertical probe needle of this example is composed of a thin metal wire 1 whose base material has a wire diameter of 0.02 to 0.04 mm and a length of 3.0 to 6.0 mm. The part 1b is covered with an insulating film 2 made of SiO ₂ and a metal film 3 having a granular protrusion 3a is formed on the tip 1a. Further, the base end portion 1c of the vertical probe needle is locked to the support plate 52a so that the barrel portion 1b does not fall out of the support plate 52a (see FIG. 12A or 12B). A stepped portion 4 is formed. As shown in FIG. 1B, the distance from the edge 2a on the distal end 1a side of the insulating coating 2 to the topmost portion 5 when measured in parallel with the length direction of the body portion 1b is L. Moreover, in this specification, the area | region including the top part 5 and its vicinity is called the front-end | tip part 1a, and let the area | region except the part contained in the front-end | tip part 1a among side surfaces be the trunk | drum 1b.

  The vertical probe needle having such a structure has an effect that the contact pressure with the object to be inspected is distributed substantially uniformly on the plurality of granular protrusions 3a. In this case, the contact resistance with respect to the inspection object is stabilized. Further, since the contact pressure with the inspection object can be increased, the oxide film formed on the surface of the inspection object is easily pierced by the tip portion 1a of the vertical probe needle. Thereby, inspection accuracy improves. In addition, since the metal film 3 is not easily worn even when the tip portion 1a of the vertical probe needle is repeatedly brought into contact with the inspection object, the above-described high inspection accuracy can be maintained for a long time. Further, when the vertical probe needle is used for the probe card, since the body portion 1b is covered with the insulating film 2, there is no possibility of short circuit even if adjacent probes come into contact with each other during overdrive. Further, since the metal film 3 is not formed on the body part 1b covered with the insulating film 2, the so-called “needle thickening” in which the diameter of the body part 1b increases due to the deposition of the metal film 3 is prevented. In this case, since the diameter of the trunk portion 1b does not become larger than necessary, the arrangement density can be increased when a large number of vertical probe needles are attached to the probe card.

Here, a method for forming the metal film 3 on the thin metal wire 1 using electrolytic plating will be described.
First, in the thin metal wire 1 made of tungsten, rhenium tungsten, beryllium copper, copper silver alloy or the like, masking is performed so that the insulating film 2 is not formed from the top 5 to the position of the distance L, and then chemical vapor deposition ( An insulating film 2 made of SiO ₂ is formed on the body portion 1b by chemical vapor deposition. Next, the metal thin wire 1 is immersed in a plating solution as a cathode, and a pulse waveform current is generated between the cathode and the anode. The plating solution contains at least one of nickel, copper, silver, gold, tin, zinc, lead, chromium, platinum, palladium, iridium and rhodium, and the anode is nickel, copper, silver, gold, zinc. , Lead, platinum, palladium, and alloys containing these are used. In this embodiment, the insulating film 2 is formed after masking. However, the present invention is not limited to this method. For example, after the insulating film 2 is formed on the entire side surface of the thin metal wire 1, a coating is required. The part of the insulating film 2 that is not to be peeled may be peeled off later. Further, the formation of the insulating film 2 is not limited to the chemical vapor deposition method, and for example, a method such as vacuum deposition can be used.

  When a current having a pulse waveform is applied between the cathode and the anode using the plating apparatus having the above structure, metal ions are deposited on the tip 1a of the thin metal wire 1, and the metal film 3 is partially formed. On the other hand, the concentration of metal ions decreases around the fine metal wire 1. Next, if the current of the pulse waveform is reduced before the metal film 3 is formed on the entire front end portion 1a, metal ions are not deposited and the growth of the metal film 3 is stopped. Thereby, innumerable minute granular protrusions 3a are formed. At this time, the consumption of metal ions in the plating solution also stops, but the metal ions move from the surroundings around the fine metal wires 1 to increase the concentration of metal ions. When the current of the pulse waveform is increased in this state, a large current flows instantaneously through the fine metal wire 1. Since this current tends to concentrate on the granular protrusion 3a, metal ions are deposited on the surface of the granular protrusion 3a as a nucleus. Thereafter, by repeating such an operation, the granular protrusion 3a grows larger. Note that the particle size and density of the generated granular projections 3a vary depending on the magnitude and cycle of the applied pulse waveform current.

  In the manufacturing method described above, a decrease in the metal ion concentration and recovery are sequentially repeated around the fine metal wire 1 immersed in the plating solution, so that a large current is instantaneously applied to the fine metal wire 1 intermittently. As a result, the metal film 3 having a plurality of granular protrusions 3a has an effect that it is formed on the tip 1a of the thin metal wire 1. Therefore, according to such a manufacturing method, the vertical probe needle having the above-described structure can be easily and inexpensively manufactured without using a large-scale manufacturing facility. In addition, the particle size and density of the granular protrusions 3a can be easily adjusted by changing the magnitude and cycle of the current of the pulse waveform to be applied. Furthermore, since the region where the metal film 3 is formed is limited by the insulating film 2, the region where the metal film 3 is deposited can be easily changed by changing the region where the insulating film 2 is deposited on the side surface of the thin metal wire 1. Can be adjusted.

  The result of the contact test using the vertical probe needle of the present invention will be described with reference to FIGS. 2 to 6 in comparison with the prior art. The magnification of the laser microscope is 3000 times, and the non-contact shape measuring devices used for measuring the three-dimensional shape are VK-9700 manufactured by Keyence Corporation and OLS4000 manufactured by OLYMPUS Corporation. In the contact test, an electrode having a surface coated with aluminum oxide sputter or the like (dry film) was used. Furthermore, in the vertical probe needle whose tip shape is shown in FIGS. 2 and 4, the radius of curvature of the top 5 (see FIG. 1) is 26 to 45 μm. Further, in manufacturing the vertical probe needle used in the following tests, all the current magnitudes and periods of the aforementioned pulse waveforms were unified to the same conditions.

2A and 2B show a case where the distance L shown in FIG. 1B is 60 μm in the vertical probe needle of the present invention. On the other hand, FIGS. 3A and 3B show the case of a conventional vertical probe needle in which a metal film having a granular protrusion is not formed at the tip. In each of FIGS. 2C and 3C, the horizontal axis indicates the number of contacts (number of contacts) of the vertical probe needle with the surface of the electrode, and the vertical axis indicates the resistance value of the tip of the vertical probe needle. Is shown.
In FIG. 2A and FIG. 2B, clean substantially spherical granular protrusions having a uniform particle diameter (particle diameter is 5 to 20 μm) are formed. As shown in FIG. 2C, the resistance value does not change even after 5000 contact tests. That is, by using such a vertical probe needle for energization inspection or the like, high inspection accuracy can be maintained for a long time.
In contrast, when a contact test is performed using a conventional vertical probe needle in which a metal film having a granular protrusion is not formed at the tip as shown in FIGS. 3 (a) and 3 (b), FIG. As shown in 3 (c), the resistance value reaches 50Ω at the maximum. It can also be seen that the resistance values are always varied and the contact resistance is not stable. This indicates that the conventional vertical probe needle cannot easily break through the aluminum oxide film on the surface of the electrode.

4 (a) to 4 (c) show cases in which the distance L shown in FIG. 1 (b) is 20 μm, 60 μm and 70 μm, respectively, in the vertical probe needle of the present invention. FIGS. 5 (a) and 5 (b) show states after 5000 contact tests are performed on the vertical probe needles shown in FIGS. 4 (a) and 4 (b), respectively.
4 (a) and 4 (b) both have clean, substantially spherical granular projections with a uniform particle size (particle size is 5 to 20 μm), whereas in FIG. The particle size of the protrusions is uneven. This indicates that when the distance L is increased, the precipitation of metal ions does not concentrate on the tip portion, so that the granular protrusions are difficult to grow uniformly.
In addition, when a contact test was performed using the vertical probe needle shown in FIGS. 4A and 4B, the resistance value was the same as in FIG. It was. Even after 5000 contact tests are performed, the state of the granular protrusions hardly changes as shown in FIGS. 5 (a) and 5 (b).
From the above, in order to form granular protrusions with uniform particle diameter at the tip of the vertical probe needle, it is necessary to make at least the above-mentioned distance L shorter than 70 μm, and desirably 60 μm or less. I know it ’s good.

6 (a) and 6 (b) show the vertical probe needle of the present invention before the contact test and after 500 times of the contact test when the distance L shown in FIG. 1 (b) is 15 μm. The state of the tip part of the vertical probe needle is shown, and FIG. 6C shows the result of the contact test.
In FIG. 6 (a), as in the case of FIG. 4 (a) and FIG. 4 (b), clean substantially spherical granular protrusions with a uniform particle diameter (particle diameter of 5 to 20 μm) are formed. However, when the contact test exceeded 500 times, the granular protrusions were peeled off as shown in FIG. Then, as shown in FIG. 6C, the resistance value starts to vary after the contact test exceeds 400 times. Thus, when the distance L is 15 μm, the granular projections formed at the tip end are easily peeled off. Therefore, in order to maintain a low resistance value for a long time, it is necessary to make the distance L longer than 15 μm, preferably 20 μm or more.
As described above, it is possible to adjust the particle size and density of the granular protrusions by changing the magnitude and period of the pulse waveform current to be applied, but only by changing the current condition of the pulse waveform. Then, it is not easy to form granular protrusions that are difficult to peel off and have a uniform particle size.

  FIG. 7A and FIG. 7B show a case where the top 5 is a dome shape and a flat shape, respectively. FIGS. 8 to 10 both correspond to FIG. 7A and show the cases where the radius of curvature of the top 5 is 9 to 21 μm, 26 to 45 μm, and 47 to 55 μm, respectively. Further, FIG. 11 corresponds to FIG. 7B and shows a case where the top 5 is flat. 8B, FIG. 9B, FIG. 10B, and FIG. 11B correspond to the two-dimensional shape in the AA cross section of FIG. 7C. In addition, the value of the radius of curvature has a width because the measured value varies depending on the location to be measured.

  In FIG. 8 (a), clean, substantially spherical granular protrusions are not formed as in the case of FIGS. 4 (a) and 4 (b). As shown in FIG. 8B, this is considered to be due to the fact that the center of the tip of the vertical probe needle is sharp, and the deposition of metal ions concentrates on the center. In this case, the effect that the contact value becomes small in the contact test described above cannot be expected. On the other hand, when the two-dimensional shape of the longitudinal section of the tip portion is represented in FIG. 9B, clean, substantially spherical granular protrusions with uniform particle diameters are formed as shown in FIG. 9A. In addition, the particle size of a granular protrusion is 5-20 micrometers, and the height of a grain is 1-2 micrometers.

  When the two-dimensional shape of the longitudinal section of the tip portion is represented in FIG. 10B, granular projections having uniform particle diameters are formed as shown in FIG. In addition, the particle size of the granular protrusion is 5 to 20 μm, and the height of the particle is about 0.2 μm. That is, the granular protrusion does not have a clean particle size as shown in FIGS. 4A and 4B, but has a crushed shape. In this case, the effect of decreasing the resistance value in the contact test described above cannot be expected. Also, in FIG. 11 (a), unlike FIG. 4 (a) and FIG. 4 (b), a metal film having a shape in which the center is depressed is formed. This is considered to be due to the fact that the deposition of metal ions concentrates on the top corner when the two-dimensional shape of the longitudinal section of the tip is shown in FIG. Also in this case, the effect of decreasing the resistance value in the contact test described above cannot be expected.

  As described above, in order to form a substantially spherical granular projection having a uniform particle diameter substantially uniformly at the tip of the vertical probe needle, the radius of curvature at the top is made larger than 21 μm and 47 μm. It is necessary to make it smaller. Desirably, the radius of curvature at the top is preferably 26 to 45 μm. In the method of changing the current condition of the pulse waveform described above, it is not easy to form a substantially spherical granular protrusion having a uniform particle diameter.

  The inventions described in claim 1 and claim 6 are not limited to probe cards, but can be applied to probe needles used for inspection of electrical characteristics of various electronic circuits and manufacturing methods thereof.

  DESCRIPTION OF SYMBOLS 1 ... Metal fine wire 1a ... Tip part 1b ... Trunk part 1c ... Base end part 2 ... Insulating film 2a ... End edge 3 ... Metal film 3a ... Granular protrusion 4 ... Step part 5 ... Topmost part L ... Distance 51 ... Vertical type probe needle 51a ... Base end part 51b ... Tip part 52a, 52b ... Support plate 53 ... Insulating coating 54 ... Wafer 55 ... Electrode

Claims (6)

In a vertical probe needle that is attached to the probe card and arranged to be substantially perpendicular to the inspection object,
The body is covered with an insulating film of SiO ₂ ,
A vertical probe needle characterized in that a metal film having a plurality of granular protrusions is formed at the tip.   2. The vertical probe needle according to claim 1, wherein the insulating film is formed such that an end edge on the tip end side is located at a distance of 20 to 60 μm from the topmost portion of the tip end portion.   3. The vertical probe needle according to claim 1, wherein the topmost portion of the tip portion is formed in an arc shape having a curvature radius of 26 to 45 μm when viewed in a longitudinal section. Forming an insulating film of SiO ₂ so as to cover the body of the thin metal wire;
At least one metal body of nickel, copper, silver, gold, zinc, lead, platinum, palladium and alloys containing these is used as an anode, and the metal thin wire is immersed in a plating solution as a cathode. Applying a pulse waveform current between the anodes;
With
A method of manufacturing a vertical probe needle, wherein a metal film having a plurality of granular protrusions is formed at the tip of the thin metal wire.   5. The method of manufacturing a vertical probe needle according to claim 4, wherein the insulating film is formed so that an edge on the tip side is located at a distance of 20 to 60 [mu] m from the topmost part of the tip. .   A step of processing the topmost portion of the tip portion into an arc shape having a radius of curvature of 26 to 45 µm as viewed in a longitudinal section before immersing the fine metal wire in the plating solution. A manufacturing method of the vertical probe needle according to claim 4 or 5.