JPH11190748A - Probe card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a probe card in which a damaged probe pin can be repaired while facilitating the wiring work. SOLUTION: A probe card comprises a board 7 having a wiring circuit, and a contactor having probe pins 1 and a circuit secured onto the surface of the board wherein the circuit 2 on the connector is connected electrically with the wiring circuit on the board through a connector 10. The connector 10 is a flexible wiring connector secured to the board adjacent to the contactor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an IC, LSI, VL
Electrical continuity test and operation test of semiconductor devices such as SI,
The present invention relates to a probe card for a probe device used for defect detection and the like.

[0002]

2. Description of the Related Art A probe card using a tungsten wire for a probe pin is known as a probe card. This is a structure in which the tip of the tungsten wire is bent into a V-shape to make contact with the evaluation electrode portion of the semiconductor. However, the wire diameter of the tungsten wire is large and cannot follow the rapid tendency to miniaturize the semiconductor. There's a problem.

Therefore, a vertical pin type probe card in which fine pins are planted substantially vertically on a substrate has been devised.
For example, a rod-shaped single crystal is formed on a silicon substrate by a VLS method (Va method).
Pour Liquid (Solid) and using a rod-shaped single crystal as a probe pin of a probe card have been proposed (JP-A-5-198636, JP-A-5-218156).

In this method, for example, an SOI wafer is used to form a wiring pattern and a VLS at a predetermined position on the wiring.
By obtaining a substrate having a rod-shaped single crystal grown by a method, and then imparting conductivity to the wiring and the rod-shaped single crystal,
A contactor having hundreds to thousands of probe pins corresponding to the C electrode with high positional accuracy can be obtained.

In actual use, the contactor is connected to a tester installed in a probe device body used for an electrical continuity test, an operation test, a defect detection, and the like, and a contact is made between the electrode of the semiconductor element and the tip of the probe pin. For this purpose, the semiconductor device is mounted on a substrate having a wiring circuit.

However, when the contactor is mounted on the board, the wiring is inevitably an ultra-fine pitch wiring pattern corresponding to the huge number of probe pins, and the wiring section on the contactor is replaced with the wiring circuit section on the board. It cannot be wired directly by soldering. Therefore, a flexible wiring circuit having a fan-shaped wiring circuit (hereinafter referred to as FPC)
In this case, the wiring pattern is enlarged, and the wiring circuit portion having a super fine pitch is bonded with an anisotropic conductive adhesive film (see FIG. 2).

[0007] By adopting the above-mentioned contrivance, the circuit on the contactor becomes an enlarged wiring circuit, and the expanded wiring circuit can be soldered to the wiring circuit on the substrate. However, even with the above contrivance, the wiring circuit portion obtained by enlarging the circuit having the ultra fine pitch has a large spread width, so that it becomes impossible to use a single circuit for practical use. Structure.

Therefore, when mounting the contactor on the substrate, the contactor is attached to the contactor with an anisotropic conductive adhesive film.
Before joining the PC, a line is attached to the enlarged pattern portion of the FPC, and thereafter, it is joined to the contactor. Next, wiring is performed at a predetermined position (a position where connection to the tester portion is easy) on the back surface via a through hole or the like of the substrate.

In the above mounting work, since the wirings are randomly overlapped with each other, it is necessary to remove the solder part of the FPC and the wiring and reuse the wiring part because there is no space for performing the soldering. However, since a short circuit due to solder cannot be avoided, it is almost impossible. In addition, a large amount of time and labor is required for connecting a large amount of wiring, and in particular, since pins are damaged or dust adheres due to slight contact or the like, careful handling is required, which is a major problem.

As described above, since the conventional probe card has a complicated wiring structure, it is necessary to replace only the contactor due to troubles in actual use of the probe card, for example, damage to some probe pins. However, there is a problem that the probe card must be replaced in units of a probe card, and it is difficult to regenerate a probe card which substantially causes inconvenience such as breakage.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances of the prior art, and has as its object to simplify the labor involved in assembling a probe card, in particular, wiring. Another object of the present invention is to provide a probe card that can be repaired by replacing only the contactor and its peripheral portion when a problem such as breakage of the probe pin occurs.

[0012]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, provided a detachable connector on a substrate, and provided a wiring conductor and a substrate enlarged by FPC via the connector. When connecting to the above wiring circuit,
It has been found that the connector vicinity is detachable, so that the connection work on the contactor side and the connection work on the wiring circuit on the board side can be separated, and the workability of the connection work is greatly improved. It is a thing.

That is, the present invention is a probe card comprising a substrate having a wiring circuit and a contactor fixed on the substrate surface and having a probe pin and a circuit,
A probe card wherein the circuit of the contactor and the wiring circuit on the board are electrically connected via a connector, preferably the connector is fixed to the board adjacent to the contactor, and the connector is flexible. The probe card which is a wiring connector, particularly preferably the probe card, wherein the probe pins are made of a single crystal grown by a VLS method.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view showing an example of the probe card of the present invention. On one main surface of the substrate 7 having the wiring circuit 12, a contactor in which the substantially vertical probe pins 1 are provided on the circuit 2 on the substrate (contactor substrate) 3 is provided.
It is provided via a pedestal 6. Although not shown,
The contactor and the pedestal 6 and the pedestal 6 and the substrate 7 are generally screw-fixed, but can be fitted or divided into one of the former and / or the latter. May be fixed by an adhesive.

The circuit 2 on the contactor is electrically connected to the FPC 5 via the anisotropic conductive adhesive 4,
Is further connected to a connector 10 provided on the substrate 7. The terminals of the connector 10 are the terminals 8 on the substrate 7,
Furthermore, it is connected to a terminal 9 for external connection via a wiring circuit 12. It is preferable that the connector 10 is provided close to the contactor, because it is easy to work and a more compact probe card can be obtained when dividing the probe card described later. Also, connector 1
As 0, various types are known,
When selecting a connector for flexible wiring, the F
It is preferable because a flexible one can be selected by the PC 5 and circuit connection and circuit disconnection can be easily performed.

Since the probe card of the present invention has the above-described structure, the contact card, the anisotropic conductive adhesive 4, the PFC 5, and the base 6
(Hereinafter, the contactor and its related parts are referred to, and the other parts except the aforementioned parts are referred to as the printed circuit board part). And, due to this feature, in the event that the probe pins are broken during use of the probe card, it can be easily repaired by exchanging the contactor and its related parts, and the wiring work itself can be performed by the contactor. And its related parts and the printed circuit board part can be divided and worked separately, so that the workability can be remarkably improved and the effect that the probe card can be manufactured at low cost can be obtained.

The contactor used in the present invention may be manufactured by any method. However, the position is controlled by the VLS method to grow a large number of rod-shaped single crystals substantially vertically on a substrate, and the rod-shaped single crystals are probed. This is a preferable method because a contactor having a pin can cope with an increase in the number of pins and the position controllability is easy.

In the present invention, regarding the size of the connector mounted on the substrate, the height of the connector is determined so that the connector can be connected to the device before the tip of the probe pin comes into contact with the device when testing a semiconductor device or the like. In order to avoid contact, it is necessary to be lower than the tip of the mounted probe pin. For the above reasons, the thickness of the connector is more advantageous as it is thinner, but on the other hand, there is a minimum in its thickness for reasons such as securing mechanical strength to function as a detachable connector, According to the study of the present inventors, the minimum thickness is about 1.5 mm. On the other hand, the maximum thickness of the connector is preferably 5 mm or less from the viewpoint of controlling the parallelism at the tip of the probe pin.

The method for producing the probe card of the present invention will be exemplified by using a contactor obtained by the VLS method, but the present invention is not limited to the following examples.

First, as for the substrate used for the contactor having the probe pins and the circuit, the thermal expansion coefficient of the obtained contactor must be close to the thermal expansion coefficient of the semiconductor element because it is necessary to face the semiconductor element of the device under test with high positional accuracy. Is desired, and a single crystal substrate of silicon is heavily used. In particular, a so-called SOI substrate in which two silicon single crystals each having an oxide film formed thereon are thermally fused and one of the single crystal layers is thinned by polishing or the like, is a thin film Si single crystal layer, an oxide film SiO 2 layer, an Si single crystal layer. It has a multilayer structure of a crystal layer and an oxide SiO2 layer, and by using this structure, a circuit composed of a thin film Si single crystal layer can be easily formed, which is preferable.

That is, a thin film Si single crystal layer of an SOI substrate is processed by a method such as photolithography or etching to form an external lead-out circuit (hereinafter, referred to as a single crystal circuit). A gold bump is provided at a predetermined position. Next, for example, silicon is supplied by a method of introducing a gas such as silicon tetrachloride and hydrogen under heating conditions, and a rod-shaped single crystal of silicon is grown substantially perpendicularly to the substrate at the position of the gold bump, that is, A substrate having a rod-shaped single crystal is manufactured by the VLS method.

Next, the length of the rod-shaped single crystal is made uniform by polishing, and the rod-shaped single crystal and the surface of each of the single-crystal circuits are made conductive by, for example, coating a conductive substance to obtain a contactor. The contactor obtained by the above method has a high position accuracy of the probe pin and is made of the same single crystal as the semiconductor element, such as the coefficient of thermal expansion, etc., so that it can be used for semiconductors of high density and high integration. It is suitable as a contactor for a probe card.

Next, the contactor manufactured by the above operation is mounted on a substrate having a wiring circuit for use as a probe card, and a single crystal circuit connected for each probe pin is connected to a wiring circuit on the substrate. I do. As the substrate, wiring corresponding to the number of probe pins is required, and the number of the wiring is several hundred to several thousand lines. Therefore, a multilayer printed wiring board is usually used.

However, in the case of connecting several hundreds to several thousands of lines, it is difficult to directly connect the lines because the lines inevitably have a superfine pattern. Therefore, it is preferable to use an FPC in which the conductor pattern is enlarged in a fan shape. Also in this case, the width of the enlarged portion becomes large, the size of the FPC itself becomes large, and it may not be possible to substantially mount the FPC on the substrate. At this time, using a plurality of FPCs, the wiring is divided into groups,
What is necessary is just to employ | adopt the structure which overlaps the wiring expansion part of FPC spatially. The connection between the single crystal circuit and the ultra-fine pattern on the FPC can be made using a commercially available film-like anisotropic conductive adhesive.

When connecting the enlarged circuit of the FPC to the wiring circuit on the substrate, the circuit on the FPC can be said to be enlarged, but it must have a fine pattern of 0.4 to 0.6 mm pitch. Since the wiring from the substrate is multiplexed, it is not easy to connect the wiring to a desired position. For this reason, conventionally, a conductor is joined to an enlarged circuit on an FPC using a solder under a microscope, and a number is marked on each of the conductors. Joined with adhesive, mounted on board,
A method of wiring to a board has been implemented. In the present invention, the wiring work can be easily performed in a short time by mounting the connector at a desired position on the substrate in advance. That is, the assembly is completed only by mounting the contactor with the FPC connected on the substrate and inserting and setting the FPC into the connector, thereby obtaining a probe card. It is desirable that the connector is provided on the substrate in advance so as to be adjacent to the contactor fixing position,
Generally, the shortest distance between the contactor and the connector is 10 to 20 mm in consideration of the mounting space for the FPC.
It is preferable that

The external output terminal portion of the substrate having a wiring circuit is generally in the form of a contact, but is provided with an electrode shape which can be mounted on a substrate having another wiring circuit, or a connector is provided in place of these electrodes. Any form, such as a thing, may be sufficient.

Hereinafter, the present invention will be described in more detail with reference to Examples.

[0028]

[Example 1] <Production of contactor> A single-crystal circuit was formed using an SOI wafer, and 460 silicon layers were formed on the single-crystal circuit in correspondence with the positions of the electrodes of the semiconductor element to be inspected. A rod-shaped single crystal was grown using the VLS growth method. The rod-shaped single crystal had a thickness of 18 μm and a length of about 1500 μm. The tip of the rod-shaped single crystal was polished to adjust the length to 1300 μm, and together with the single crystal circuit, electroless nickel plating was performed, followed by gold plating to a thickness of 1.5 μm. Further, after the side surfaces of the probe pins were insulated, the electrode portions used for plating were cut to produce contactors.

<Connection of FPC to Contactor> Anisotropically conductive bonding four polyimide film-based FPCs having 95 conductor lines expanded in a fan shape and two FPCs having 40 conductor lines expanded in a fan shape on the opposite surface The film was connected to a single crystal circuit of the contactor via a film.

<Mounting of SMT FPC Connector on Board> After solder paste is printed on conductor terminals corresponding to connector electrodes on a disc-shaped multilayer resin substrate having a diameter of 20 cm, the SMT FPC connector (Japan Airlines) (Electronic Industry Co., Ltd.) and heat-bonded.

<Assembly of Probe Card> A contactor having an FPC bonded via a titanium pedestal having a thickness of 3 mm is mounted almost at the center of the board on which the connector is mounted, and the end of the FPC is inserted and set in the connector. Assembly was completed. The pedestal was fixed to the center of the substrate with fixing screws. This assembly time was completed in about one hour.

[Second Embodiment] The same operation as in the first embodiment is performed up to the connection of the FPC to the contactor.
When mounting a T-type FPC connector, use an SMT type FPC.
A solder paste is printed on a board on which a disk-shaped auxiliary board having a diameter of 10 cm having conductor terminals corresponding to the electrodes of the PC connector is mounted, and an SMT type FPC connector (manufactured by Japan Aviation Electronics Industry) is installed. Heat bonding was performed.
The probe card was assembled in the same manner as in Example 1. The assembly time at this time was about 1 hour.

Comparative Example Using the same contactor as in Example 1, an insulated wire was soldered to the enlarged terminal portion of the FPC, and the wiring order was marked in units of 10 and bound. Next, the superfine part was joined to the pin chip via an anisotropic conductive adhesive film. About 8 hours were spent on these tasks.

Next, F with a large number of insulated wires
The pin chip to which the PC was bonded was mounted and fixed on the board, and the insulation-coated wires were peeled off and soldered one by one at the wiring connection position of the board. Since these operations are equipped with fine pins, they require careful attention such as contact and adhesion of dust, and as a result, they take about 30 hours to complete the operation. An error has occurred.

[0035]

According to the probe card of the present invention, since the circuit on the contactor and the wiring circuit on the board are electrically connected via the connector, the contactor, its related parts and the wiring circuit board can be easily formed. The feature is that it is divided into For this reason, partial repair, which could not be achieved with the conventional probe card, has become possible. In addition, wiring work can be performed in a divided state, and a probe card can be stably manufactured in a short time. It has a special effect and its industrial value is high.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a probe card according to the present invention.

FIG. 2 is a cross-sectional view of a conventionally known probe card.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Probe pin 2 Circuit on contactor (single crystal circuit) 3 Contactor board 4 Anisotropic conductive adhesive 5 FPC 6 Pedestal 7 Board 8 Terminal on wiring circuit on board 9 Terminal on wiring circuit on board (external connection) 10) Connector 11 Conductor 12 Wiring circuit inside the board 13 Solder

Claims (4)

[Claims] 1. A probe card comprising a substrate having a wiring circuit and a contactor fixed on a surface of the substrate and having a probe pin and a circuit, wherein a circuit on the contactor and a wiring circuit on the substrate are connected via a connector. A probe card, which is electrically connected to the probe card. 2. The probe card according to claim 1, wherein the connector is fixed to the substrate adjacent to the contactor. 3. The probe card according to claim 1, wherein the connector is a connector for flexible wiring. 4. The probe card according to claim 1, wherein the probe pins are made of a single crystal grown by a VLS method.