JP2006275543A - Probe device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a probe device capable of performing precise contact with electrodes under test of a narrow pitch such as a chip size package and securely establishing conduction. <P>SOLUTION: The probe device 1 is provided with a flexible film substrate 3 consisting of an insulating material, contact terminals 4 consisting of a plurality of conductive patterns formed in parallel on the film substrate 3, an elastically deformable reinforcement plate 5 stuck on the rear side of the film substrate 3, and a substrate holding mechanism 6 holding the film substrate 3, the contact terminals 4, and the reinforcement plate 5 in the curved state and bringing the tips of the contact terminals 4 into press contact with the electrodes under test. The tips 13 of the contact terminals 4 coincide with one end of the film substrate 3 and are arranged so as to agree with the pitch of the electrodes under test. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a probe device, and more particularly to a probe device that is electrically connected to an electrode to be inspected when testing a semiconductor integrated circuit.

  In recent years, a semiconductor integrated circuit in a package form called a chip size package (CSP) has been widely used to meet the demand for downsizing electronic components. In such a semiconductor integrated circuit, the external electrodes of the IC package and the pitch thereof are miniaturized.

  By the way, in order to inspect the characteristics of a semiconductor integrated circuit, there is known an IC inspection apparatus that conducts a continuity test by electrically contacting an external electrode of an IC package and a large number of contact pins installed in a socket. In the manufacturing process of a semiconductor integrated circuit, after a chip diced from a wafer is sealed in a package, a burn-in test is performed prior to shipment. In this test, an external electrode of an IC package is connected to a contact pin mounted on a socket, and a semiconductor integrated circuit is continuously operated in a high temperature atmosphere for several hours while supplying power from an external power source to a chip in the package. It is a test to inspect electrical characteristics.

  A specific configuration of the probe in the IC inspection apparatus will be described. The contact pin has a contact electrode that contacts an external electrode of the IC package and a connection electrode connected to a terminal of the test circuit, and a spring is provided between the contact electrode and the connection electrode. ing. In other words, the contact electrode is brought into electrical contact with the external electrode of the IC package with an appropriate pressure applied by the biasing force of the spring.

  Note that the above-described prior art is a general matter that is naturally understood by those skilled in the art, and the applicant is not particularly aware of any literature suitable for specifying the prior art.

  However, the conventional IC inspection apparatus has a large number of contact pins arranged in accordance with the external electrodes of the IC package. Since each contact pin is biased by a coil spring, It has been difficult to reduce the pitch. In other words, with the miniaturization of the pitch of the external electrodes in the CSP and other IC packages, the miniaturization of the pitch of the contact pins in the IC inspection device is naturally required, but the inspection device is manufactured under the restriction of the coil spring. It was difficult.

  In addition, if the height of each electrode varies due to warpage of the wafer or package on which the integrated circuit is formed, or dimensional errors of the solder balls or package, it is difficult to reliably contact the contact pins. There was a fear. In particular, when the electrode is formed of solder, the surface is covered with a thin oxide film due to oxidation in the air, so that the contact is made when the pressing force of the contact pin against the external electrode is weak However, there was a risk that it could not be conducted.

  Therefore, in view of the above situation, the present invention provides a probe device that can cope with a narrow-pitch inspection electrode such as a CSP with high accuracy and can be reliably conducted. It is to be an issue.

The probe device according to the present invention includes a “flexible substrate made of an insulating material,
A plurality of conductive patterns formed in parallel on the substrate, the tip of which coincides with one end of the substrate, and a plurality of contact terminals arranged in accordance with the pitch of the electrode to be inspected;
A substrate holding mechanism that holds the substrate in a curved state and presses the tip of the contact terminal against the electrode to be inspected ”.

  According to the present invention, the substrate is held by the substrate holding mechanism, and the plurality of contact terminals extending to one end of the substrate are brought into pressure contact with the electrodes to be inspected. In particular, the contact terminal is composed of a conductive pattern formed on the substrate, and is brought into pressure contact with the electrode to be inspected while being curved together with the substrate. In other words, since the contact terminal is pressed against the electrode to be inspected using the elastic force of the substrate, a coil spring or the like is not necessary, and the pitch of the contact terminal facing one end of the substrate can be miniaturized. . That is, it becomes possible to cope with the inspection electrodes with a narrow pitch. Further, the contact force of the contact terminal with respect to the electrode to be inspected changes depending on the curvature of the substrate. That is, by adjusting the curvature rate of the substrate, it is possible to set the pressure contact force of the contact terminal to an appropriate pressure.

  Further, the substrate can be slid while the substrate is curved in a constant state, that is, the contact terminal is pressed against the electrode to be inspected with a constant pressure. Therefore, the oxide film on the surface of the electrode to be inspected can be scraped off by the tip of the contact terminal without applying a large load to the electrode to be inspected, and the contact terminal can be conducted to the electrode to be inspected. In particular, since the tip of the contact terminal is located at the edge of the substrate, stress is concentrated and the oxide film can be easily scraped off. At the same time, self-cleaning of the contact terminal itself is also performed.

  By the way, in the probe device of the present invention, even if the “the substrate is composed of a flexible film substrate and a reinforcing plate capable of elastic deformation is attached to the back surface of the substrate” is adopted. Good.

  Here, examples of the “film substrate” include a flexible film substrate made of an insulating material such as polyimide resin. Examples of the “reinforcing plate” include a metal plate such as stainless steel.

  According to this, even when a flexible flexible film substrate, which is often used as a flexible substrate, is used, the film substrate is fixed in a certain posture (planar shape) by sticking the reinforcing plate. In the case of bending, an elastic force is generated, and the contact terminal can be brought into pressure contact with the electrode to be inspected by the elastic force.

  In the probe device of the present invention, a configuration in which “a notch-like slit is formed between the tips of the plurality of contact terminals in the substrate and the reinforcing plate” may be employed.

  According to this, the tips of a plurality of contact terminals face one end of the substrate in parallel, but a notch-shaped slit is formed between the tips of each contact terminal, and the substrate and the reinforcing plate are The so-called comb shape. For this reason, even if the height of each electrode varies due to warpage of the wafer or package, or dimensional error of the solder ball or package, the tip portion of each contact terminal is individually deformed according to the height difference. That is, by forming the slit, it is possible to absorb the height variation in each electrode to be inspected.

  As described above, in the probe device according to the present invention, the contact terminal is brought into pressure contact with the electrode to be inspected by using the elastic force of the substrate, so that the pitch of the contact terminal facing one end side of the substrate can be miniaturized. Also, it is possible to cope with a narrow pitch inspection electrode such as CSP with high accuracy. In addition, the oxide film on the surface of the electrode to be inspected can be efficiently removed, and electrical conductivity between the contact terminal and the electrode to be inspected can be ensured. Further, by adjusting the curvature of the substrate, it is possible to set the pressure contact force of the contact terminal to an appropriate pressure, and it is possible to prevent the electrode to be inspected from being scratched or dented. Further, since the inductance of the contact terminal is small and there is no expansion / contraction, the change in inductance is small, so that the inspection accuracy can be improved.

  Hereinafter, a probe apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a perspective view showing the configuration of the probe apparatus. The probe device 1 of the present embodiment is used when conducting a continuity test or a burn-in test on a semiconductor integrated circuit having a narrow pitch inspection electrode 2 (see FIG. 2) such as a chip size package (CSP). Is.

  As shown in FIG. 1, the probe device 1 includes a film substrate 3, a plurality of contact terminals 4 formed on the film substrate 3, and a reinforcing plate 5 attached to the back surface of the film substrate 3. Yes. The film substrate 3 is a flexible substrate made of an insulating material such as polyimide resin, and is called a so-called flexible substrate. The thickness of the film substrate 3 is not particularly limited, but is about 30 to 50 μm in this example. The film substrate 3 of this example includes a wide base portion 3a, a narrower pattern forming portion 3b, and a narrower contact portion 3c, and is formed in a step shape as a whole. A plurality of slits 8 are formed in the contact portion 3c, which will be described later.

  The contact terminal 4 is composed of a plurality of conductive patterns formed in parallel on the film substrate 3, and the tip 13 coincides with one end (the upper end in FIG. 1) of the film substrate 3 and matches the pitch of the electrode 2 to be inspected. Are arranged. In this example, the thickness of the contact terminals 4 is 5 to 20 μm, and the pitch of the contact terminals 4 at the tip 13 is 40 μm. Each contact terminal 4 extends in parallel from the contact portion 3c to the base portion 3a of the film substrate 3, and circular pitch conversion portions 10 arranged in a staggered manner are provided at the end portion on the base portion 3a side. Is formed. That is, by arranging in a staggered manner, the interval at the end of the contact terminal 4 is widened, and the pitch is changed from a narrow pitch arrangement corresponding to the electrode 2 to be inspected to a wider pitch (for example, 50 μm). It has been converted. A through hole 9 for taking out a signal through the contact terminal 4 is formed at the end of each contact terminal 4 whose pitch has been changed. The through hole 9 is formed through the film substrate 3 and the reinforcing plate 5.

  The reinforcing plate 5 is made of a metal plate such as stainless steel, holds the film substrate 3 in a fixed posture (planar shape), and generates an elastic force when bent. The shape of the reinforcing plate 5 is the same as that of the film substrate 3 and is formed in a step shape.

  In the contact portion 3c of the reinforcing plate 5 and the film substrate 3, a notch-shaped slit 8 is formed between the plurality of contact terminals 4, and has a so-called comb shape. For this reason, although each contact terminal 4 is a slight range, it becomes possible to change the amount of bending individually.

  On the other hand, the film substrate 3 and the reinforcing plate 5 are supported by the support portion 12 of the substrate holding mechanism 6. The substrate holding mechanism 6 is connected to an arm of a driving means (not shown), and the tip 13 of the contact terminal 4 can be brought into pressure contact with the electrode 2 to be inspected while the film substrate 3 and the reinforcing plate 5 are curved. I have to. Further, the film substrate 3 and the reinforcing plate 5 can be slid in the horizontal direction while being curved in a constant state, that is, with the contact terminal 4 being pressed against the electrode 2 to be inspected at a constant pressure. I have to.

  Next, the operation of the probe apparatus 1 will be described with reference to FIG. The film substrate 3 and the reinforcing plate 5 are held by the substrate holding mechanism 6, and a plurality of contact terminals 4 extending to one end of the film substrate 3 are brought into pressure contact with the respective electrodes 2 to be inspected. In particular, the contact terminal 4 is brought into pressure contact with the electrode 2 to be inspected in a curved state together with the film substrate 3 and the reinforcing plate 5. At this time, since the reinforcing plate 5 has an elastic force, the contact terminal 4 can be brought into pressure contact with the electrode 2 to be inspected using the elastic force.

  Further, since the contact terminal 4 is slid while being kept in press contact with a constant pressure, the oxide film on the surface of the electrode 2 to be inspected and the oxidation of the tip 13 of the contact terminal 4 are not applied to the electrode 2 to be inspected. The film can be removed, and as a result, the contact terminal 4 can be reliably conducted to the electrode 2 to be inspected.

  Further, since the notched slits 8 are formed between the tips 13 of the adjacent contact terminals 4, for example, due to warpage of the wafer or package on which the integrated circuit is formed, or dimensional error of the solder ball or package, Even if the heights of the electrodes vary, the tip portions of the contact terminals 4 are individually deformed according to the height difference. That is, the height variation in each of the electrodes to be inspected 2 is absorbed by the slit 8.

  By the way, when using the probe apparatus 1 of this example for a burn-in test, it is preferable to cool the probe apparatus 1 using a cooling device or the like. That is, in the burn-in test, the semiconductor integrated circuit is continuously operated for several hours in a high temperature atmosphere. However, if the probe device 1 that is a contact portion is cooled, thermal deformation of the film substrate 3 is suppressed, The pitch of the contact terminals 4 can be maintained.

  Thus, in the probe apparatus 1 of this example, the contact terminal 4 is pressed against the electrode 2 to be inspected by using the elastic force of the film substrate 3 and the reinforcing plate 5, so that a coil spring or the like is not required, and the film substrate It is possible to reduce the pitch of the contact terminals 4 facing the one end side of 3. Therefore, it is possible to contact with a narrow pitch inspection electrode 2 (for example, 40 μm) such as CSP with high accuracy. In particular, by using the reinforcing plate 5, the film substrate 3 can be held in a fixed posture (planar shape), and when it is bent, an elastic force is generated, and the contact terminal 4 is fixed by the elastic force. The pressure can be brought into contact with each other.

  In addition, the oxide film on the surface of the electrode to be inspected 2 can be efficiently removed, and electrical conductivity between the contact terminal 4 and the electrode to be inspected 2 can be ensured.

  Furthermore, in the probe device 1 of this example, since the notch-shaped slit 8 is formed between the tips 13 of the contact terminals 4, it is possible to absorb the height variation in each of the electrodes 2 to be inspected.

  Moreover, in the probe apparatus 1 of this example, since the contact terminal 4 is comprised using the electrically conductive pattern formed in the film substrate 3, it can be manufactured comparatively cheaply and the installation cost concerning a burn-in test etc. is large. Can be reduced.

  Moreover, in the probe apparatus 1 of this example, it becomes possible to set the press-contact force of the contact terminal 4 to an appropriate pressure by adjusting the curvature rate of the film substrate 3, and damage the electrode 2 to be inspected. It is possible to prevent dents from being generated. Further, since the inductance of the contact terminal 4 is small and there is no expansion / contraction, the change of the inductance 4 is small, so that the inspection accuracy can be improved. Furthermore, since the contact terminal 4 is formed by the conductive pattern extended from the contact portion, the number of contact points is reduced, and the conductivity can be further improved.

  The present invention has been described with reference to preferred embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention as described below. And design changes are possible.

  That is, in the probe device 1 described above, a plurality of electrodes to be inspected 2 arranged in a row are shown as inspection targets, but a plurality of electrodes to be inspected 2 are inspected in a plurality of rows. As shown in FIG. 3, a plurality of probe devices 1 can be arranged in parallel at a predetermined interval. That is, a plurality of contact terminals 4 arranged in a matrix can be contacted to each electrode 2 to be inspected while being bent at the same time.

  In the above probe device 1, the film substrate 3 is used as the substrate, and the reinforcing plate 5 is attached to the back surface of the film substrate 3. However, the probe device 1 is harder and more elastic than the film substrate 3 (for example, If the substrate is formed of glass epoxy resin), the reinforcing plate 5 can be omitted, and the whole structure and manufacturing method can be further simplified.

  In the above embodiment, the CSP external electrode is contacted as the electrode to be inspected. However, it is made to contact the electrode at the wafer level (die level) which is a stage before commercialization. Also good.

  In the probe device 1 described above, the contact terminal 4 is slid while being pressed against the electrode 2 to be inspected at a constant pressure. For example, between the contact terminal 4 and the electrode 2 to be inspected. Alternatively, the contact terminal 4 may be slid with a thin sheet member interposed therebetween, and after the contact terminal 4 reaches a predetermined position, the sheet member may be pulled out. According to this, since the frictional resistance of the contact terminal 4 with respect to the electrode 2 to be inspected is reduced, it becomes possible to prevent the electrode 2 to be inspected from being damaged.

  In the probe device 1 described above, the through hole 9 for extracting a signal is formed at the end of the contact terminal 4. However, the process for processing the signal detected by the contact terminal 4 is shown. A circuit may be formed on the film substrate 3 and connected to the contact terminal 4 on the conductive pattern. According to this, the contact terminal 4 and the processing circuit are formed on the same substrate, so that the cost can be reduced and the maintenance of these can be facilitated.

  Further, in the above probe device 1, a plurality of contact terminals 4 are arranged in parallel and the pitch is increased by the pitch converters 10 arranged in a staggered manner, but the plurality of contact terminals 4 are fan-shaped (radial). Even if they are arranged in this manner, the pitch on the end side can be increased. However, by arranging a plurality of contact terminals 4 in parallel as in the above embodiment, the probe device 1 can be reduced in size and weight.

It is a perspective view which shows the structure of the probe apparatus of this invention. It is explanatory drawing which shows the use condition of a probe apparatus. It is explanatory drawing which shows the example of application of a probe apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Probe apparatus 2 Electrode to be inspected 3 Film substrate (substrate)
4 Contact terminal 5 Reinforcing plate 6 Substrate holding mechanism 8 Slit

Claims (3)

A flexible substrate made of an insulating material;
A plurality of conductive patterns formed in parallel on the substrate, the tip of which coincides with one end of the substrate, and a plurality of contact terminals arranged in accordance with the pitch of the electrode to be inspected;
A probe apparatus comprising: a substrate holding mechanism that holds the substrate in a curved state and presses the tip of the contact terminal against the electrode to be inspected. The substrate is composed of a flexible film substrate,
The probe device according to claim 1, wherein a reinforcing plate capable of elastic deformation is attached to the back surface of the substrate.   The probe device according to claim 2, wherein a notch-shaped slit is formed between tips of the plurality of contact terminals in the substrate and the reinforcing plate.

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