JPH07288271A - Measuring electrode for integrated circuit - Google Patents

Abstract

PURPOSE:To highly accurately bring contacts into contact with pads on a pattern relevant to an individual IC part by a method wherein a conductive and buffer member electrically connects base lands with opposed lands and moves a contact block in a contact direction toward a relay substrate. CONSTITUTION:A conductive and buffer member 50 electrically connects base lands 32 relevant to a base 10 and a relay substrate 60 with opposite lands 61 for performing electrical connection and buffering. The member 50 moves a contact block 20 provided on the base 10 toward the relay substrate 60 in a contact direction of pads 2 of an object to be examined. This movement regulates a position with fitting of a guide boss 72 for alignment provided on a support base 70, a guide boss 72 for alignment provided on the base 10 and a semicircular recess 11 provided on the base 10. Thus the contact block 20 can be highly accurately brought into contact with the pads 2 on a pattern concerned with an individual IC part.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a measuring electrode for an integrated circuit.

[0002]

2. Description of the Related Art Conventionally, a wafer related to a semiconductor integrated circuit (IC) is cut into individual pellets, and the pellets are mounted on a lead frame and packaged by molding or the like. And aging, and there was also a device to measure the characteristics of pellets addressed to one piece. The measuring electrode used in such a case requires a small number of contact points, and there is no problem in the conventional technique in terms of design and work.

However, such inspection and aging methods take time and are not suitable for production. Also,
It takes a lot of time and effort to attach and detach the finished product IC, and when a defective product occurs, all the processes up to that point are wasted, which is a great pain especially for products with poor yield. Was there.

Therefore, in order to avoid waste of the process up to that time when defective products are detected and removed from the packaged ICs in the process near the final process, a plurality of integrated circuit devices and a plurality of integrated circuit devices grown on the wafer are omitted. It has been proposed that the pellets containing individual elements be measured at one time to prevent waste of subsequent steps and to significantly improve production efficiency.

[0005]

However, at present, in a pellet or an IC wafer having a plurality of semiconductor circuit parts mounted thereon, the distance between adjacent IC patterns is about 20 μm, and the electrode parts (pad parts) on the pattern are mutually separated. The distance between them is very small, about 30 μm, and in particular, in an 8-inch wafer, several hundreds to several thousands of IC patterns are grown, so that the number of pads is several tens per pattern. In terms of degree, the number of wafers per wafer is in the range of thousands to tens of thousands, and further tends to become finer with the trend toward higher integration.

When simultaneously measuring all of a large number of IC portions (subjects) formed on such an object to be measured, there are local and global irregularities on their surfaces, and therefore all It has been extremely difficult to achieve contact with the pad portion with high accuracy and high reliability. In addition, since the pins involved in probing are expensive and delicate, or the area of the contact block for one object is large, it is very possible to manufacture a prober that can simultaneously measure many objects. It was difficult.

In order to solve the above-mentioned problems of the prior art, an object of the present invention is to attach an inspection device for an IC and an aging device (hereinafter, both are collectively referred to as a main device) to A contact that allows highly accurate and reliable contact with the pad part on the pattern related to each IC part in the wafer state before cutting the IC into single or plural pellets or pellets. A measuring electrode for an integrated circuit (hereinafter, referred to as a measuring electrode) having the integrated circuit is provided.

Another object of the present invention is to grow on a wafer in order to eliminate waste of the process up to that time when defective products are detected and removed from the packaged IC in the process near the final stage. By enabling measurement of multiple integrated circuit devices or those cut into pellets containing multiple devices at one time, it is possible to prevent waste of subsequent processes and improve production efficiency, and By extending the configuration, it is possible to determine the distribution state of defective portions on the wafer, and to retroactively determine process defects such as defective IC pattern masks. Providing a measurement electrode that can be expected to have a wide range of applications, which can be applied to defect inspection devices other than IC wafers such as liquid crystal display devices with electrodes. It is to be.

[0009]

The measuring electrode for an integrated circuit according to the present invention is used for measuring an object in which a plurality of integrated circuits are arranged and their pad portions are arranged on one surface. A relay board, a contact block, a first conductive and cushioning member disposed between the relay board and the contact block, the relay substrate, the contact block, and the first conductive and cushioning member. And a support base for positioning and holding each other, the contact block includes a contact having a contact portion capable of contacting each of the pad portion of the subject, each contact is , The contact block being held by the contact block by a second conductive and cushioning member that allows the contact to move in the contact direction with respect to the pad portion. , The first corresponding to each contact 2
Is provided with a base round electrically connected to its contact point through the conductive and cushioning members, and the relay board is provided with an opposing round point corresponding to each of the contact points and electrically drawn to an external measuring device. Are arranged, the first conductive and cushioning members electrically connect the corresponding base round and the opposing round, and the contact block moves in the contact direction with respect to the relay board. It is characterized by making it possible.

[0010]

Since the measuring electrode for an integrated circuit of the present invention has such a structure, the presence of the first conductive and cushioning members can cope with global distortion and unevenness of the surface of the subject, and
The presence of the conductive material and the cushioning member makes it possible to cope with local strains and irregularities on the surface of the subject, and to make it possible for each contact point to contact all the pad parts of the subject with high accuracy and reliability. There is.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the accompanying drawings.

FIG. 1 is a plan view showing one of the contact blocks of a measuring electrode for an integrated circuit as one embodiment of the present invention, and FIG. 2 is a sectional view taken along the line AA 'of the contact block of FIG. Is. The contact block comprises a base 10 made of ceramic. Contact points 20 are provided on the base 10 at positions corresponding to the pads of the subject. Therefore, through holes 12 are formed in the base 10 by the printed circuit board manufacturing technology and the through hole technology, and the through holes 12 are electrically interconnected to the upper and lower surfaces near each through hole 12. A contact round 30 is formed. Furthermore, on the upper surface of the base 10, there are provided a base round 32 for electrical connection with a relay board, which will be described later, and a connection conductor 31 electrically connecting each of the base rounds 32 to a corresponding contact round 30. Has been formed. As well shown in FIG. 1, semicircular recesses 11 are formed at both ends of the base 10 as positioning engaging portions that perform the operations described below.

As shown in FIG. 2, in this embodiment, the contact 20 has an arrowhead-shaped contact portion 21 that comes into contact with the pad portion of the subject and a cylindrical extension extending upward from the contact portion 21. And a portion 22. The hole diameter in the through hole 12 is slightly larger than the outer diameter of the extension of the contact 20. Therefore, each contact 20 can freely move up and down when the extension 22 is inserted into each through hole 12 of the base 10.

As best shown in FIG. 2, each contact 2
A circular conductive rubber 40 serving as a second conductive and cushioning member for coping with local unevenness of the subject is interposed between 0 and the corresponding contact round 30.
The conductive rubber 40 has a central portion extending from the extension 22 of the contact 20.
An opening is formed so as to pass through. In this embodiment, two conductive rubbers 40 are provided so as to be electrically connected to each of the contact rounds 30 provided on the upper and lower surfaces of the base 10. These conductive rubbers 40 not only hold each contact 20, but also electrically connect each contact 20 to the contact round 30 and, at the same time, exert a buffering action so that each contact 20 can move up and down.

In this embodiment, upper and lower conductive rubbers 40 are provided.
However, the present invention is not limited to this, and the conductive rubber may be provided only in the upper contact round or the lower contact round. In particular, contact round 30
When the conductive rubber piece is provided only above, the through hole and the lower contact round can be omitted, and the configuration can be simplified.

As the second conductive and cushioning member, in addition to conductive rubber, a coil spring-like member made of metal or plastic having conductivity by plating the surface is used. Alternatively, a washer type or a diaphragm type can be used. However, when a conductive rubber type is applied at least below the contact 20 and the contact round 30, some friction between the contact 20 and the base 10 or the through hole 12 may cause the surface to be inspected. It is possible to prevent the material particles from falling.

FIG. 3 is a sectional view similar to FIG. 2, showing one of the contact blocks of the measuring electrode for an integrated circuit as another embodiment of the present invention. The structure of the contact block in this embodiment is largely the same as the contact block described with reference to FIGS. 1 and 2, so only the different parts will be described. Instead of the conductive rubber 40 in the contact blocks of FIGS. 1 and 2, a conductive rubber 40A obtained by cutting a sheet-like material into a ring shape is provided only on the lower contact round 30 side. The conductive rubber 40A is provided between the contact round 3 on the lower side and the contact portion 21 of the contact 20, holds the contact 20 with respect to the contact round 30, electrically connects the contact rubber, and moves the contact 20 in the vertical direction. Also acts as a buffer against.

FIG. 4 shows one of the contact blocks of the measuring electrode for an integrated circuit according to still another embodiment of the present invention.
4 is a sectional view similar to FIG. The structure of the contact block in this embodiment is almost the same as that of the contact block described with reference to FIGS. 1 to 3, and therefore only different parts will be described. In this embodiment, a sheet-shaped insulating member 40B is used as the second conductive and cushioning member. The sheet-like insulating member 40B is made of a conductive rubber having conductivity only in the portion 41B necessary for conduction with the contact 20A, that is, in the vicinity shown by hatching. In this case, the conductive rubber portion 41B is formed by forming the upper end of the extension portion 22A extending from the contact portion 21A of the contact 20A into a needle shape.
The contact 20A can be mounted only by piercing the needle-shaped upper end of the navel, and the process can be greatly simplified.

FIG. 5 is a sectional view showing a state in which the measuring electrode for an integrated circuit of the present invention using a plurality of contact blocks as described with reference to FIG. 3 is applied to a subject. The measurement electrode of this embodiment is configured so that a plurality of integrated circuits contained in the subject can be measured simultaneously. This measurement electrode is provided with a relay board 60, and the relay board 60 has a base round 32 provided on the base 10 of the contact block as an electrical relay means between each contact block and the main device. Opposing rounds 61 having the same arrangement as the above are formed corresponding to the number of contact points 20.

Then, between the base round 32 and the facing round 61 of the relay substrate 60 facing the first round, the signal of the measurement block is basically used to deal with the global unevenness of the measuring object which is the subject. As the first conductive and cushioning member, a sheet member 50 made of an anisotropic conductive material having elasticity in the thickness direction and conductivity only in the thickness direction is arranged.
In this embodiment, the sheet member 50 is made of a so-called anisotropic conductive rubber material.

The facing round 61 of the relay board 60 is formed by the printed wiring 62 laid on the relay board 60.
It is connected to the connector 80 and is connected to the main device by a cable 81.

As the first conductive and cushioning member 50,
Conductivity and elasticity only in the longitudinal direction like anisotropic conductive rubber,
Any material having flexibility can be used, and a flexible printed board or the like can also be used. However, it can be said that the anisotropic conductive rubber is preferable in terms of easiness of electrical connection between the base round and the opposing round.

The measuring electrode of this embodiment is provided with a support base 70. The support base 70 includes a relay board 60, contact blocks 10, 20, 30 and 40, and a first conductive and buffer member. It is for positioning and holding 50 with respect to each other. In this embodiment, the relay board 60 is bonded to the support base 70 to correct the distortion. The support base 70 is made of a material having a coefficient of thermal expansion close to that of the semiconductor substrate 1 which is an object (such as LEX series manufactured by Nippon Foundry Co., Ltd.), and has sufficient rigidity and small strain. Is configured.

As the aligning means for accurately bringing the contact 20 into contact with the pad portion 2 of the subject, for example, a guide is provided on 2 to 4 sides of the contact block, or a cylinder and a cylinder are provided so as to be movable only in the vertical direction. Base 1 with a structure consisting of a piston and a spring inside if necessary 1
Various methods such as supporting 0 can be considered, but in any case, it is necessary to have a structure that can move lightly only in the vertical direction but can regulate the position of the base 10 and the subject 1 in the other directions with sufficient precision. In this embodiment, the following structure is adopted.

FIG. 6 is a view of a part of the measurement electrode of FIG. 5 viewed from the contact side, and shows the alignment state of the contact block with respect to the arrangement of the pad portion 2 of the subject 1.
In this embodiment, the guide boss 72 for alignment provided on the support base 70 and the semicircular recess 11 provided on the base 10 are used.
The position is regulated by fitting with. The dimensional accuracy is regulated so that the play between the guide boss 72 and the semi-circular recess 11 is small and the base 10 can be easily moved vertically. The position regulation of the relay board 60 is also performed by the guide boss 71 coaxial with the guide boss 72 of the support base 70.

Further, means for conducting and buffering the base round 32 relating to the base 10 and the relay substrate 60 and the opposing round 61, that is, the first conductive and buffer member 5.
As described above, the anisotropic conductive rubber is used as 0. The structure of the anisotropic conductive rubber will be described in detail below.

As shown in FIG. 7, the anisotropic conductive rubber includes a rubber or polymer sheet 51 having electrical insulation, elasticity and flexibility, and a large number of metal, carbon, conductive rubber or polymer. Conductive thin wire 52 of 0.05-0.2mm
It is made to have both conductivity, elasticity and flexibility only in the thickness direction by penetrating in the longitudinal direction at a small interval. FIG. 8 shows a modified example of such an anisotropic conductive rubber. In this case, a conductive thin wire is provided over the entire rubber or polymer sheet 53 having electrical insulation and elasticity and flexibility. Instead of arranging, the conductive thin wire 54 and the one in which lateral position resolution is not required only in the portion where conductivity is required according to the specifications are simply provided with blocks such as conductive rubber.

In the above-described embodiment, one of the IC patterns of the subject 1 and one contact block correspond to each other, and the relay substrate 60 and the support base are provided for an object including a plurality of IC patterns. Although a plurality of contact blocks having the same number as the IC patterns are put together by 70 or the like, the present invention is not limited to this. For example, as shown in FIG. 9, a single contact block corresponding to a plurality of IC patterns can be used. The contact block shown in FIG. 9 is one in which the contacts 20 corresponding to the pad portions of the six IC patterns are arranged on the base 10A.
Conductive rubber 40 is attached to each contact 20 at the center of the base 10A.
A, base round 32A electrically connected via contact round (not shown) and connecting conductor 31A
Are arranged together. Base 10 of this contact block
At both ends of A, guide bosses 7 of the support base are also provided for position regulation.
A semicircular recess 11A that engages with 2A is formed. In this example, the contact blocks for the six IC patterns can be replaced by one contact block for a wafer including a larger number of IC patterns as long as the flatness is good.

Further, the base 10 and the relay substrate 60 may be formed of a semiconductor material. In this case, the circuit and the base relating to the connection between the contact block and the relay substrate and the connection between the relay substrate and another device. It is possible to form functional circuits such as a driver circuit and an interface circuit at the same time as rounds, contact rounds, and opposite rounds. By doing so, the integration degree of IC patterns will increase in the future, and the pitch and size of pad portions will further increase. It can be used even if it becomes fine.

Although the contacts in the above-mentioned embodiments are of a pointed type as a whole, the present invention is not limited to this. For example, as shown in FIG. 10, a metal ball having a spherical shape or a shape that can be approximated to a spherical shape may be used as the contact 20B. In this case, by appropriately selecting the diameter of the hole formed in the base 10 or the contact round 30 with respect to the diameter of the metal ball 20B, when the metal ball 20B is mounted on the base 10, the conductive rubber 40C is applied to the conductive rubber 40C with an appropriate pressure. There is also an advantage that the contacts are naturally positioned by simply pressing them.

Further, as shown in FIG. 11, if necessary, the contact point can be pressed against the through hole 12 formed in the base 10 by using the correction plate 90 having the small hole 91. , It is also possible to have a shape in which the center is automatically obtained. That is, the contact 20C has a spherical shape with a large curvature at the upper end and a spherical shape with a small curvature at the contact portion 21C. Contact point 20C having such a shape
Fits the contact portion 21C into the corresponding small hole 91 of the straightening plate 90 and contacts the contact 20C toward the base 10 with the upper end applied to the lower end of the through hole 12 via the conductive rubber 40C. By pressing it, the center is automatically obtained and the correct positioning is performed. Similar to the contact 20D, the same effect can be obtained even if the upper end has a truncated cone shape. In addition, such automatic positioning of the contact is performed by forming a conical groove in the center of the columnar conductor mounted so as to penetrate the substrate instead of using the through hole as described above. It can also be achieved by pressing a contact having the above-mentioned shape against this.

In the embodiment described above, the support base 70,
The relay substrate 60, the first conductive and cushioning member 50, the base 10, the second conductive and cushioning members 40, 40A and the contact 20 are held to each other by adhesion, but the present invention is not limited to this, and other Various means can be adopted. For example, as a method of supporting the contact block on the relay board 60 or the support base 70, the base round 3
Each of the two rounds and the opposing round 61 may be bonded with a conductive rubber to replace the first conductive and cushioning member. Further, in the anisotropic conductive rubber 50, which is the first conductive and cushioning member, a method of applying an insulating adhesive to the upper and lower portions of the vicinity of the center, which is not related to the round, and fixing the same can be considered.

FIG. 12 is a partial sectional view similar to FIG. 5, showing a measuring electrode as still another embodiment of the present invention. In this embodiment, the contact block base 10
The through hole 13 is formed in B, the through hole 55 is formed in the first conductive and cushioning member 50A, the through hole 63 is formed in the relay substrate 60A, and the through hole 73 is formed in the support base 70A, and they are formed on the upper surface of the support base 70A. Fixed pin 101 and contact 20E
And the through holes 13, 55, 63, and 73 between them, the pull-tightening member 100 is pulled, so that the relay board 60A, the first conductive and cushioning member 50A, and the base 10B with respect to the support base 70A. , The second conductive and cushioning member 40A and the contact 20E are fixedly held. This has the advantage that the contact block can be easily replaced when it is damaged. As the pull-tightening member 100, a wire having a proper length, a lot, or a spring having a proper spring constant can be used.

[0034]

EFFECTS OF THE INVENTION The measuring electrode for an integrated circuit of the present invention is provided with a plurality of contact blocks, and by using the first conductive and cushioning members and the second conductive and cushioning members, a single test object is obtained. Needless to say, it can handle local and global distortion and bending of wafers and a large number of large-scale integrated circuits, and can make highly accurate and reliable contact with the pad part of the subject, as well as assembling man-hours and time. It is possible to provide a highly economical prober that can significantly reduce the cost.

[Brief description of drawings]

FIG. 1 is a plan view showing one of contact blocks of a measuring electrode for an integrated circuit as an embodiment of the present invention.

2 is a cross-sectional view of the contact block of FIG. 1 taken along the line AA ′.

FIG. 3 is a sectional view similar to FIG. 2, showing one of contact blocks of a measuring electrode for an integrated circuit as another embodiment of the present invention.

FIG. 4 is a sectional view similar to FIGS. 2 and 3, showing one of contact blocks of a measuring electrode for an integrated circuit according to still another embodiment of the present invention.

5 is a cross-sectional view showing a state in which the measuring electrode for an integrated circuit of the present invention using a plurality of contact blocks as described with reference to FIG. 3 is applied to a subject.

6 is a view of a part of the measurement electrode of FIG. 5 viewed from the contact side.

FIG. 7 is a diagram showing a structural example of anisotropic conductive rubber used in the measuring electrode for integrated circuit of the present invention.

FIG. 8 is a diagram showing another structural example of the anisotropic conductive rubber used for the measuring electrode for integrated circuits of the present invention.

FIG. 9 is a view showing another embodiment of the contact block used for the measuring electrode for integrated circuit of the present invention.

FIG. 10 is a diagram showing another example of the shape of the contact used for the measuring electrode for integrated circuit of the present invention.

FIG. 11 is a view showing still another example of the shape of the contact used for the measuring electrode for integrated circuit of the present invention.

FIG. 12 is a partial sectional view similar to FIG. 5, showing a measurement electrode as still another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Test object 2 Pad part 10 Base 11 Semi-circular recessed part 12 Through hole 20 Contact point 21 Contact part 22 Extension part 30 Contact round 31 Connection conductor 32 Base round 40 Conductive rubber 40A Conductive rubber (2nd conductive and buffer member) 50 Anisotropic Conductive conductive material sheet member (first conductive and cushioning member) 60 relay board 61 facing round 62 printed wiring 70 support base 71 guide boss 72 guide boss 80 connector 81 cable

Claims (13)

[Claims] 1. A measuring electrode for an integrated circuit, wherein a plurality of integrated circuits are arranged and their pad portions are arranged on one surface, which is used for measuring an object, a relay substrate, a contact block, and the relay. A first conductive and cushioning member arranged between the substrate and the contact block; and a support base for positioning and holding the relay substrate, the contact block and the first conductive and cushioning member relative to each other. Is equipped with
The contact block includes a contact having a contact portion capable of contacting each of the pad portions of the subject,
Each of the contacts is retained in the contact block by a second conductive and cushioning member that allows the contact to move in the contact direction relative to the pad portion relative to the contact block. Corresponding to each contact, a base round electrically connected to the contact via the second conductive and buffer member is provided, and the relay board corresponds to each of the contacts and an external measuring device. Opposing first rounds electrically connected to the base rounds and the opposite rounds corresponding to each other, and the contact blocks contact the contact rounds. A measuring electrode for an integrated circuit, which is movable in a direction with respect to the relay substrate. 2. The integrated circuit according to claim 1, wherein the first conductive and buffer member is made of an anisotropic conductive material having elasticity in a thickness direction and conductivity only in a thickness direction. Measuring electrode. 3. The first conductive and cushioning member is formed of a conductive material having elasticity.
A measuring electrode for an integrated circuit as described. 4. The contact block is formed with a through hole having a contact round, and the base round and the second conductive and cushioning member are electrically connected via the contact round. The measuring electrode for an integrated circuit according to claim 1, 2, or 3. 5. The contact has an extension extending from the contact, and the second conductive and cushioning member has an opening penetrating the extension of the contact. The measurement electrode for an integrated circuit according to claim 4, wherein the extension portion of the contact is inserted into the opening and the through hole of the second conductive and buffer member. 6. The contact has an extension extending from the contact, and a tip of the extension is shaped so as to be pierced by the second conductive and cushioning member. The measuring electrode for an integrated circuit according to claim 4, wherein the extension of the contact is inserted into the second conductive and buffer member and the through hole. 7. A positioning engagement portion is formed on the relay board and the contact block, and the support base is engaged with the positioning engagement portion to form the relay board and the contact block. The measuring electrode for an integrated circuit according to claim 1, further comprising a position determining portion for determining a positional relationship. 8. The fixing of the relay board to the support base, the fixing of the first conductive and cushioning member to the relay board, the fixing of a contact block to the first conductive and cushioning member, and the second The measurement electrode for an integrated circuit according to claim 1, wherein the contact and the cushioning member are fixed to each other by adhesion. 9. The relay substrate, the first conductive and cushioning member, the contact block, the second conductive and cushioning member, and the contact are fixed to the support base by the contact and the support base. The measuring electrode for an integrated circuit according to any one of claims 1 to 7, which is performed by a tensioning member that is detachably connected between the two. 10. The measuring electrode for an integrated circuit according to claim 1, wherein the contact block is formed by an integrated circuit manufacturing technique including the base round. 11. The relay substrate is formed by a semiconductor integrated circuit manufacturing technique so as to have a circuit related to connection with an external measuring device and a functional circuit such as a driver circuit and an interface circuit at the same time including a facing round. The measuring electrode for an integrated circuit according to any one of claims 1 to 10. 12. The contact has a spherical shape or a shape similar to a spherical shape such that when the contact is pressed against a through hole provided in the contact block, the center is automatically obtained with respect to the through hole. Claims 1 to 11
The measuring electrode for an integrated circuit according to any one of 1. 13. The base of the contact block is formed of an insulator such as ceramic, glass, or plastic, or a metal having an insulating film on the surface thereof.
3. The measuring electrode for integrated circuit according to any one of 2.