JPH10221366A - Probe pin and inspecting device equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a probe pin which has stable long life by forming the major constituent of a probe pin of tungsten containing a predetermined proportion of rhenium. SOLUTION: Tungsten powder and rhenium powder are mixed so that the content of rhenium may be in the range of 3-30wt.%. The mixed powder is shaped into a rod, provisionally sintered, and sintered by the passage of electric current in a non-oxidizing atmosphere. Rolling and hammering process and wire drawing process are applied on the sintered body to obtain a predetermined wire rod. After straightening process, cutting, plating, tip bending process, polishing, and prober assembling, the wire rod is processed into a probe pin in the shape of a subject. The speed of wire drawing in the wire drawing process is approximately 1.2-1.5 times faster than that in regular tungsten process, and the hardness of a probe pin is approximately 800HV or more. In addition, the time for mixing powder raw materials is approximately 10 times longer than before, and the Young's modulus of a probe pin is approximately 3.7×10<5> N/mm or more. Through the use of an inspecting device equipped with a probe pin manufactured in this method, it is possible to perform satisfactory measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a probe pin used in an inspection apparatus for inspecting whether a semiconductor device such as a semiconductor integrated circuit (IC) operates normally, and an inspection apparatus having the probe pin.

[0002]

2. Description of the Related Art Conventionally, a probe has been used to inspect electrical characteristics of a semiconductor integrated circuit (IC), a liquid crystal display (LCD), and the like. The inspection is performed by directly applying a probe pin to the terminal of the object to be inspected. The probe pin is mainly formed by processing a tungsten wire having a diameter of about 0.25 mm into a needle shape. The characteristics required of such a probe pin include that it does not deform due to contact with the terminal of the device under test, and that the contact pressure is constant, the contact resistance is low, and there is no change.

If the probe pins are deformed due to contact with the terminals of the device to be inspected and are not restored, the contact between the probe pins and the terminals of the device to be inspected becomes defective, and the inspection becomes impossible.

In recent years, the degree of integration of ICs has rapidly increased, and accordingly, the diameter of probe pins mounted on a prober has been further reduced, the distance between pins has been reduced, and the mounting structure of probe pins has been reduced to a flat surface. It has become necessary to adopt a three-dimensional method (a vertical tip method in which the tip is machined into a needle shape and sharpened or not machined in a needle shape).

[0005] When the probe pin diameter is reduced, the number of pins arranged per unit area can be increased, which is advantageous for the inspection of an IC with a high degree of integration. However, deformation is caused by contact with the IC terminal. This is likely to occur, and the problem of poor contact occurs early.

In order to solve this problem, tungsten having a higher strength than tungsten and containing a small amount of rhenium has been used as a material of the probe pin. This tungsten is for a filament of a bulb which generally contains 3% by weight of rhenium.

[0007]

However, in the future, I
As the degree of integration of C increases, the wire diameter of the probe pin also increases.
It is expected that the number of probe pins arranged thinner and per unit area will also increase. Also, the cost of assembling the IC prober is increased, and the process loss due to poor contact with the IC terminals is further increased. Therefore, conventional tungsten or tungsten containing 3% by weight of rhenium is insufficient. It has been desired to develop an alternative stable wire rod.

In view of the above circumstances, an object of the present invention is to provide a probe pin which is stable under any use conditions and has a long service life in place of conventional tungsten or tungsten containing 3% by weight of rhenium. Another object of the present invention is to provide a semiconductor inspection device having such a probe pin.

[0009]

In order to solve the above problems, the present invention (claim 1) is characterized in that the main component is tungsten containing more than 3% by weight and not more than 30% by weight of rhenium. The present invention provides a probe pin for a semiconductor inspection device.

That is, the probe pin for a semiconductor inspection device according to the present invention is characterized in that, as a constituent material, tungsten in which rhenium is dissolved at a higher content than before is used. The rhenium content of tungsten is preferably 5 to 26% by weight, more preferably 10 to 26% by weight.
% By weight.

If the rhenium content of tungsten is 3% by weight or less, the effect of the present invention that the amount of deformation that increases with the frequency of use is reduced cannot be obtained. Meanwhile, 3
If the content exceeds 0% by weight, rhenium segregates, the workability in forming a wire decreases, and the production cost increases because rhenium is expensive.

According to the findings of the present inventors, when a wire made of rhenium-containing tungsten is processed into a probe pin, its hardness has a great influence on the deformation during use. In general, tungsten containing rhenium is used in a high-temperature environment such as a tube member and a heater member after a recrystallization treatment, so that the hardness at room temperature before the recrystallization is not given much importance. However, when the content of rhenium in tungsten increases, the workability when processing into a wire rod is significantly reduced.Therefore, in order to produce with a good yield, processing at a high temperature and a strain removal step in the middle process are required. Need to be repeated. For this reason, the hardness after finishing the wire rod processing is low, and it is difficult to increase the hardness even if the rhenium content is high. On the other hand, when the content of rhenium is lower than 3% by weight, processing can be performed at a lower temperature without repeating the strain removing step, but a longer life probe pin is required. It was difficult to work harden to hardness.

The present inventors have made various adjustments to the conditions for processing tungsten containing rhenium exceeding 3% by weight and not more than 30% by weight into a wire rod, so that a probe pin having a good yield and a long life can be obtained. It has been found that a required high hardness wire can be processed. That is, when the probe pin is formed by processing rhenium-containing tungsten, in order to reduce the amount of deformation during use, the hardness of the wire is desirably high, and is preferably 800 HV or more in Vickers hardness, and more preferably. Has a Vickers hardness of 830 HV or more. When the Vickers hardness is lower than 800 HV, the amount of deformation increases, and the life as a probe pin is shortened.

Further, the present inventors have found that, when a wire made of tungsten containing rhenium is processed into a probe pin, the Young's modulus of the wire is changed in the contact pressure (needle pressure) with the terminal of the test object during use. Found to have a great effect. If the Young's modulus is low, the contact pressure with the terminal of the device under test such as an IC decreases with the number of contacts due to the fatigue phenomenon of the probe pin, which causes a problem of malfunction.
In other words, when processing rhenium-containing tungsten to form a probe pin, in order to suppress a change in the contact pressure of the probe pin during use, the Young's modulus of the wire is 3.7 × 10
₅ N / mm ² or more, preferably 3.85 × 10 ₅
N / mm ² or more. This Young's modulus is 3.7 × 10 ₅
If it is lower than N / mm ^2, the change in contact pressure due to use becomes large, and the life as a probe pin is shortened.

Further, the present inventors have found that the content exceeds 3% by weight.
For tungsten containing less than 0 wt% rhenium,
It has been found that the number of crystals in the cross section of the wire affects the contact resistance that increases with the number of contacts with the IC terminal.
The cross section in the present invention is a cross section when cut perpendicular to the central axis in the length direction of the wire.

That is, the tungsten constituting the probe pin for a semiconductor inspection device of the present invention preferably has a crystal number of 64,000 to 192,000 / mm ² in a cross section. Here, if the number of crystals exceeds 192,000 / mm ² , the contact resistance increases in proportion to the number of contacts with the IC terminal or the like, while the number of crystals becomes 64000 / m 2.
If it is less than m ² , many breaks occur during wire drawing. More preferred number of crystals is 96,000 to 16000
0 / mm ² .

Next, an example of the method for producing the probe pin of the present invention described above will be described. First, a tungsten powder and a rhenium powder were mixed by a conventional method so that the rhenium content exceeded 3% by weight and was 30% by weight or less. Next, after the mixed powder was formed into a rod shape, it was provisionally and electrically sintered in a non-oxidizing atmosphere such as hydrogen to obtain a sintered body.

The obtained sintered body was subjected to rolling and drawing to obtain a predetermined wire. Thereafter, the obtained wire was processed into a probe pin having a target shape. In this process, the wire was straightened, and thereafter, cut, plated, bent at the tip, polished at the tip, and assembled with a prober.

In order to increase the hardness of the probe pin to 800 HV or more in terms of Vickers hardness, the wire drawing speed in the wire drawing step should be about 1.2 to 1.5 times that of ordinary tungsten processing. Good. That is, increasing the drawing speed is
This has the effect of raising the processing temperature and reducing the amount of heat applied to the wire. Therefore, by raising the processing temperature by this method, the problem of a decrease in yield, that is, the occurrence of cracks, is solved, and the amount of heat applied to the wire is reduced by 80%.
It can have a hardness of 0 HV or more.

The probe pin has a Young's modulus of 3.7 ×
In order to achieve 10 ₅ N / mm ² or more, it is important to adjust the production method of the raw material powder, that is, to disperse and mix the rhenium powder finely and uniformly in the tungsten powder at the time of preparing the raw material. For mixing time of powder,
By mixing for a long time, preferably 10 times or more, rhenium can be miniaturized and uniformly dispersed and mixed, and the Young's modulus can be increased to 3.7 × 10 ₅ N / mm ² or more.

The number of crystals in the cross section is 64,000 to 19
In order to obtain 2,000 pieces / mm ² , before processing to a predetermined size at a processing rate of 77 to 90%, heat treatment is performed at 1450 to 1550 ° C. in an air atmosphere or a hydrogen atmosphere, and a strain removing step is performed. The number of crystals can be set to the above number.

The probe pin of the present invention can be used for a commonly used inspection device such as a prober. By using the inspection device provided with the probe pin of the present invention, satisfactory measurement can be performed. It is possible to obtain an inspection device that can be performed.

Here, as the prober, for example, there is one having a configuration shown in the schematic diagram of FIG. FIG. 4A shows a normal type prober in which the tip of a probe pin 2 arranged on a base comes into contact with an object to be inspected 4 such as an IC while being inclined.
In (b), the tip of the probe pin 2 arranged on the base is I
This is a vertical prober having a relationship of making vertical contact with the test object 4 such as C. The configuration of these probers is not limited at all in the present invention.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, various examples will be shown as embodiments of the present invention, and the present invention will be described more specifically. (Example 1) Tungsten powder having an average particle size of 3 µm and rhenium powder having an average particle size of 2 µm were mixed by a conventional method so that the content of rhenium was 20% by weight with respect to tungsten. Here, the mixing time is conventionally 1 hour compared to 2 hours when producing a rhenium-tungsten wire for a tube, for example.
This was performed for 20 hours at 0 times. Next, this mixed powder was molded at a molding pressure of 200 MPa, and the mixture was heated at 130 MPa in a hydrogen atmosphere.
After preliminary sintering at 0 ° C., electric current sintering was performed to obtain a 1.5 kg sintered body.

Subsequently, the sintered body was rolled and drawn to obtain a wire having a diameter of 0.65 mm. In this wire drawing, the wire drawing speed was variously changed in order to change the Vickers hardness. Next, in order to change the number of crystals,
Wire rod processed to φ0.65mm in air atmosphere 15
The sample was heat-treated at 00 ° C. to remove the strain, and a sample in which the strain was not removed was also prepared.

Finally, wire drawing is performed to a predetermined wire diameter, and surface electrolytic polishing is performed as finishing.
A 25 mm tungsten wire containing 20% by weight rhenium was obtained. The obtained wire was straightened and cut, and finally processed into a probe pin shape as shown in FIG.

Samples of four types of probe pins were prepared by the above method, and the Vickers hardness and the number of crystals were measured for these samples. The Vickers hardness is 5
The measurement was performed at 00 gf and a retention time of 30 seconds, and the number of crystals was magnified 5000 times with an electron microscope to make the number of crystals visually observable. The results are shown in Table 1 below.

[0028]

[Table 1]

The above sample Nos. The amounts of deformation of the probe pins 1 to 4 were measured using an evaluation device as shown in FIG. The measurement method is as follows.
The amount of upward deformation and the contact resistance when the probe pin 2 was pressed 200,000 times with the load described above were measured. The measurement results are shown in Table 2 below.

[0030]

[Table 2]

As is clear from Table 2 above, Sample No. having a Vickers hardness of 850 was used. The probe pins 1 and 2 do not deform much, but have a Vickers hardness of 7
Sample No. 00 The deformation amounts of the probe pins 3 and 4 are as large as 1 mm. In addition, the sample No. When the probe pin contact resistances of Nos. 1 and 2 are compared, No. No. 1 probe pin is no. Half of two,
It can be seen that good contact resistance is shown. In addition, the sample No. The same tendency was observed for the probe pins Nos. 3 and 4; 1,
The contact resistance is higher than that of the second probe pin, which is not preferable.

As is clear from the above results, the probe pin of the present invention has a Vickers hardness of 800 HV or more, and a crystal number of 64,000 to 192,000 / m 2.
In the case of m ² , it can be seen that the deformation resistance and the contact resistance are particularly good.

Example 2 A tungsten powder having an average particle size of 3 μm and a rhenium powder having an average particle size of 2 μm were mixed with a tungsten having a rhenium content of 3, 5, 15, 2 with respect to tungsten, respectively.
It was mixed by a conventional method so as to be 6,30% by weight. The mixing time here is 20 hours. Then, molding pressure 2
After molding at 00 MPa and pre-sintering at 1300 ° C. in a hydrogen atmosphere, electric current sintering was performed to obtain a 1.5 kg sintered body.

Subsequently, the sintered body was rolled and drawn to obtain a wire having a diameter of 0.65 mm. Next, φ0.6
The wire rod processed to 5 mm was heat-treated at 1500 ° C. in the atmosphere to remove distortion. Finally, wire drawing was performed to a predetermined wire diameter, and surface electropolishing was performed as finishing to obtain tungsten wires having various rhenium contents of φ0.25 mm. The obtained wire was straightened and cut, and finally processed into a probe pin shape as shown in FIG.

By the above method, five types of probe pin samples (sample Nos. 5 to 10) in which the rhenium content of tungsten was changed were prepared.
Vickers hardness was measured. The result is shown in FIG. From the results shown in FIG. 3, it can be seen that the higher the rhenium content, the higher the hardness.

Subsequently, in the same manner as in Example 1, the sample No. With respect to 5 to 10 probe pins, the amount of deformation was measured using the evaluation device shown in FIG. The measurement results are shown in Table 3 below.

[0037]

[Table 3]

As is clear from Table 3, as the rhenium content increases, the amount of deformation decreases, but if it exceeds 30% by weight, rhenium segregates and processing is extremely difficult. When the rhenium content was 3% by weight, the deformation amount reached 1.5 mm, which was a problem in practical use.

Example 3 A tungsten powder having an average particle diameter of 3 μm and a rhenium powder having an average particle diameter of 2 μm were mixed by a conventional method so that rhenium was 15% by weight and 26% by weight with respect to tungsten, respectively. Here, the mixing time is 2 hours and 2 hours, respectively. Next, after temporary sintering at 1300 ° C. at a molding pressure of 200 MPa, electric current sintering was performed to obtain a 1.5 kg sintered body.

Subsequently, the sintered body was processed in the same manner as in Example 2 to obtain rhenium-tungsten having a diameter of 0.25 mm. The Young's modulus of these obtained wires was measured. The measurement results are shown in Table 4 below. The measurement of the Young's modulus was performed by fixing both ends of the wire to a room-temperature tensile tester with a chuck so that the evaluation distance was 230 mm, and a dynamic strain gauge extensometer (Instron 2620-60) was attached to the center of the wire.
4) is attached, the load change when strain is applied at a pulling rate of 0.2 mm / min is read on a chart, and this is a value obtained by calculation.

[0041]

[Table 4]

As is apparent from Table 4, the longer the mixing time, the higher the Young's modulus, and the higher the rhenium content, the higher the Young's modulus. In the same manner as in Examples 1 and 2, the sample No. Regarding the probe pins made of the wire rods of Nos. 11 to 14, using the evaluation device shown in FIG.
The change in the contact angle when the stroke to the pad was kept constant was measured. The measurement results are shown in Table 5 below.

[0043]

[Table 5]

As is clear from Table 5, the probe pin having the Young's modulus specified in the present invention has a small change in the contact pressure and has excellent characteristics. As described above, Examples 1 to
When the probe pin of the present invention described in Example 3 was used as a probe pin of an inspection device such as a prober used for inspection of a semiconductor integrated circuit or a liquid crystal display device, a stable measurement result could always be obtained, Measurement was able to be performed.

[0045]

As described above, the present invention uses tungsten containing more than 3% by weight and 30% by weight or less of rhenium as a constituent material, so that the number of times of contact with the IC terminal is increased. However, it is possible to provide a probe pin having a small amount of deformation, a constant contact pressure, a low contact resistance, and excellent characteristics.

Further, by using the probe pin of the present invention as a probe pin of a commonly used inspection device such as a prober, it is possible to provide an inspection device capable of performing good measurement.

[Brief description of the drawings]

FIG. 1 is a diagram showing the shape of a probe pin.

FIG. 2 is a view showing a test apparatus for evaluating characteristics of a probe pin.

FIG. 3 is a characteristic diagram showing a relationship between rhenium content and Vickers hardness.

FIG. 4 is a schematic diagram showing a configuration of a prober.

[Explanation of symbols]

 1. Al pad 2. Probe pin 3. Base 4. Inspection object

Claims (5)

[Claims] 1. A probe pin comprising, as a main component, tungsten containing more than 3% by weight and not more than 30% by weight of rhenium. 2. The probe pin according to claim 1, wherein the tungsten has a Vickers hardness of 800 HV or more. 3. The tungsten has a Young's modulus of 3.7.
The probe pin according to claim 1, wherein the probe pin has a density of at least 10 ⁵ N / mm ² . 4. The number of crystals in a cross section is 64,000 to 1920.
00 pieces / mm ² professional according to claim 1, characterized in that - Bupin. 5. An inspection apparatus comprising the probe pin according to claim 1.