KR20050091013A - Adapter for testing conductor arrangements - Google Patents

Abstract

The invention relates to an adapter (3, 5) for testing a conductor arrangement (2), especially for testing a chip carrier. One such conductor arrangement comprises contact sites on one side, which are not arranged according to a high density and are interspaced at a minimum distance of, for example, 0.5 mm. Said adapter has at least one contact field (17) provided with respectively one set of contact elements. The contact elements of the contact field enable contact to be made with the conductor arrangement contact sites arranged according to a low density. The contact elements of said contact field are electrically connected to respectively one contact element of said contact field or another contact field, such that the strip conductors of two conductor arrangements are electrically interconnected and can be simultaneously tested.

Description

Adapter for Testing Conductor Arrangements

The present invention relates to an adapter for inspecting one or more conductor assemblies. In particular, the present invention relates to adapters for inspecting non-componented conductor assemblies, such as circuit boards and other substantially substantially substrates. Such conductor assemblies are, for example, chip carriers having a chip face provided with contacts for connecting to an integrated circuit and a connection face provided with larger contacts for connecting to another conductor assembly. These contacts on the connection surface may be arranged in a regular grid.

Known devices for the inspection of unconstituted circuit boards can in principle be divided into two groups. The first group includes devices using adapters called so-called parallel testers, in which all the contacts of the circuit board can be contacted simultaneously using the adapter. The second group has so-called finger testers. These are devices that sequentially scan each contact using two or more test fingers.

Testers using adapters are disclosed, for example, in DE 42 37 591 A1, DE 44 06 538 A1, DE 43 23 276 A, and EP 215 146 B1 and DE 38 38 413 A1.

These adapters are basically used to match the irregular arrangement of the contacts on the circuit board under test with the preset basic grid of the electrical tester. In current circuit boards under test, the test points are no longer arranged in a uniform lattice, so that the contact needles in the adapter making the connection between the contact grid and the contacts are arranged to be inclined or deflected, or so-called transistors with a uniform contact grid. To "move" into an irregular arrangement of the contacts. Thus, these adapters are also known as grid matching adpaters.

Each of the conductive path of the non-voice circuit board, regardless of the type of the device, is checked for disconnection ( "open circuit test") and the electrical connection to the other conductive path ( "short-circuit inspection") in the conductor path. Short checks may include detection of both low and high impedance connections.

Other measurement techniques are known for both open circuit inspection and short circuit inspection. Since this technique involves checking each conductor path for shorts and for each branch of the conductor path for disconnections, for modern circuit boards with multiple conductor paths, many individual measurement operations must be performed accordingly.

A circuit board inspection method in which a nonuniform electrical field is applied to a circuit board under test is known from EP 0 508 062 B1, in which a potential formed by the non-uniform electric field is drawn out by a measuring probe at a contact point, and The potential is compared with the potential and / or reference potential at other test points. This method is called field measurement.

Another improved method of this field measurement is described in EP 0 772 054 A2. In another method of such field measurement, in the first circuit board inspection, for each conductor path, a short circuit by field measurement and a disconnection by resistance measurement are checked. As a result, from the measured values, the admittance used as reference admittances in another circuit board inspection is calculated. By using these reference admittances in another circuit board inspection, each conductor path can be inspected for both short and broken lines by field measurements.

US 5,268,645 corresponds to EP 0 508 062 B1 and US 5,903,160 corresponds to EP 0 772 054 A2. The disclosures of these references are all incorporated by reference.

DE 197 00 505 A1 has a short circuit for a plurality of power nets and / or ground nets on the circuit board, and signal nets with high test voltages for a combination of these nets. A circuit board inspection method for inspecting is disclosed. The method involves first providing a high potential to the combination of networks and then examining the respective signal networks for that combination. Thereby, since the signal network does not need to be individually inspected for each power supply network and / or the grounding network, it is possible to drastically reduce the time-consuming inspection count due to the high voltage involved.

In the inspection of so-called chip carriers, certain demands are placed on the inspection apparatus. A chip carrier is a small circuit board or conductor having one or more contacts on one side, ie on the chip side, in which one or more integrated circuits can be directly connected without casing and electrically connected to the contacts of the chip carrier by bonds. Assembly. The contacts on the chip face are each electrically connected by conductor paths to the contacts corresponding to the chip carrier, ie on the connection face. The chip carrier may have a three-dimensional structure (see US 5,006,093).

The contacts on the chip surface are generally small and arranged very close to each other. In technical terms this is referred to as "high-pitch". The contacts on the connecting surface are usually large and usually arranged in a grid. Typically a ball grid array (BGA) is provided. The chip carrier may, for example, are described in the ^{MC 2 M ® BGA Type Multi-} Chip Modules. This publication is available on the Internet at www.valtronic.ch. Another chip carrier is disclosed, for example, in US Pat. No. 5,066,963.

The contacts on the chip face of the chip carrier are very precisely arranged and arranged close to each other so that they cannot be contacted with a conventional adapter. Therefore, such a chip carrier cannot be inspected using a parallel tester. Chip carriers are mass produced in very large quantities. With a conventional finger tester, the contacts on the chip surface can be contacted, but the inspection using the conventional finger tester cannot be economically performed because it takes too much time to sequentially scan all the contacts in the inspection of the chip caherer. Thus, for the chip carrier inspection, a specific inspection apparatus has been developed which includes an adapter having contact elements arranged to coincide with the contacts of the chip carrier on the contact surface, in order to contact the contact surface. Usually the contact elements of the adapter are arranged in a given grid, in particular in a BGA grid. On the other hand, the chip surface of the chip carrier is contacted by the contact finger moving freely. Thus, the chip carrier inspection device is a combined parallel / finger tester. Using such a device, high throughput can be achieved in the inspection of chip carriers. However, since it is necessary to provide electronic evaluation devices suitable for finger testers as well as electronic evaluation devices suitable for parallel testers, these specific devices are very expensive, while the inspection devices are only used for very specific conductor assemblies, i.e., chip carriers. Can be.

An unconfigured circuit board inspection device is known from US 2001/013783 A1. The device has a so-called probe section that can be compared with an adapter and provided with a plurality of probes. The circuit board under test is placed in this probe section. There is an insulating film on the circuit board under test. Test heads having a probe tip are provided on the insulating thin film, and the test head can be moved to contact each circuit board inspection point over the insulating thin film. The probe of the probe unit is connected to the electronic evaluation device through a switching device. The unit consisting of the probe unit, the switching electronics and the evaluation device forms a parallel tester.

Electronic circuit board inspection devices are known from DE 44 17 580 C2. These inspection devices are designed for inspection of circuit boards provided with electronic components. The inspection apparatus described herein has an adapter in the form of a bed-of-nail, on which the substrate under test can be placed. The top surface of the substrate containing the electronic component is contacted by a sensor array having contact pins that can be moved over the substrate. Functional testing of the individual electronic components is done with such a device similar to the combined parallel / finger tester described above.

Adapters or electronic testers for circuit boards with plugs such as pads made of electrically conductive elastic elastomer on the contact area are known from DE 38 38 413 A1.

EP 0 772 054 A2 relates to a method used in connection with a finger tester, but the use of an adapter is not disclosed in this document.

Accordingly, the present invention is based on the problem of providing a simple and cost effective means of inspecting a chip carrier or a very fast non-component conductor assembly very similar to a chip carrier using conventional test apparatus.

The problem is solved by an adapter having the features of claim 1. Advantageous modifications are shown in the dependent claims.

An adapter according to the invention for inspecting one or more conductor assemblies having a plurality of conductor paths in a finger tester, the conductor assembly having one surface provided with contacts arranged at least at predetermined intervals from the nearest contact, One side can be contacted by the adapter,

The adapter having at least one contact field with a set of contact elements, the contact elements of the contact field arranged in a configuration in accordance with the contacts of the conductor assembly,

The contact elements of the contact field may be combined to form another test net having one or more contacts on at least one surface on which the conductor path of the conductor assembly is not contacted by an adapter. Are electrically connected to each other.

Accordingly, the present invention makes an adapter that can be used to contact a conductor assembly on one side, wherein the conductor path of the conductor assembly is electrically connected to one or more other conductor paths of this or another conductor assembly. The test nets thus formed have at least one contact on the face of the conductor assembly not contacted by the adapter, so that these test nets can be contacted by the test fingers of the finger tester. All conductor paths under test are part of the test net that can be contacted on the face of the conductor assembly that cannot be contacted by the adapter.

Such a system of adapters and one or more conductor assemblies can be mounted to the finger tester and the test net can be scanned. Due to the fact that the multiple conductor paths through the adapter are combined in the test net, each measuring operation involves simultaneous examination of multiple conductor paths, which means that the test speed is significantly increased compared to the conventional test in the finger tester. it means.

However, since the adapter itself is not directly connected to the electronic evaluation device, it can be manufactured easily and cost-effectively, as in the case of the conventional parallel tester. This applies in particular when the contacts of the conductor assembly are arranged in some desired standard grid. For such conductor assemblies, under certain conditions, even standardized adapters can be used, and do not need to be specifically designed for that conductor assembly.

According to a preferred embodiment of the invention, the conductor path of the conductor assembly is electrically connected via the adapter such that the test net has at least two contacts on the face of the conductor assembly which are not in contact by the adapter. The provision of at least two contacts in the test net enables the open circuit inspection of the test net by resistance measurement. Good mass production of conductor assemblies requires that the conductor path of the conductor assembly be inspected for disconnection by resistance measurements, because there is an opinion that such resistance measurements are most reliable even in the case of high impedance rupture.

Thus, with an adapter designed in this way, the conductor path of the conductor assembly can be quickly and easily checked for disconnection in the finger tester using resistance measurements. In this specification, the adapter is not connected to the electronic evaluation device by itself, but only to the tester finger. Accordingly, the adapter according to the present invention is economical to use such an adapter to check any conductor assembly previously tested only with a parallel tester or a specially designed testing device with a finger tester due to the reduced test time, thus making it possible to perform a finger test. Cost effective to manufacture and expand the field of use.

The adapter according to the invention also allows inspection in a single sided finger tester of the conductor assembly having contacts on two sides. Thus, with the adapter according to the invention, the scope of application of the conventional single-sided finger tester can be extended to conductor assemblies having contacts on two sides. Using the adapter according to the invention, the conductor paths of different conductor assemblies can also be electrically connected together in one test net. Furthermore, multiple conductor assemblies can be provided on one adapter, the conductor paths in one conductor assembly being electrically connected to one another via the adapter, and the conductor paths of the other conductor assembly being tested by the adapter. Are connected to form a net.

Preferably, many conductor paths are electrically connected together by an adapter to form several test nets, ideally two test nets. In the present specification, so-called shielded adjacency criterion is contemplated for convenience: that is, another conductor path that is not part of the test net, in view of its position in the conductor assembly, is arranged between the conductor paths, or in the conductor assembly. Since the boundary layer is formed at another position of, only the conductor path which cannot form a short circuit with the other conductor path of the test net is connected together by the adapter. The connection of conductor paths to several test nets can reduce the measurements in the short-circuit test to only a few measurement operations, in which case only individual test nets have to be measured against each other.

Due to the limited number of test nets, the provision of the minimum number of test nets allows the use of high test voltages without significant time loss, since the boosted voltage has to be raised only a few times. This principle is described in DE 197 00 505 A1, to which reference is made.

In particular, when a field measurement method is used, test nets can be inspected for shorts in one test sample, and the test net can also be inspected for disconnections if an appropriate reference spot is available.

These test measurements can be made with known finger testers, and the throughput is not lower than using an inspection device designed specifically for the inspection of chip carriers. In the use of field measurement, the throughput can even be increased.

The invention is explained in detail by way of example with reference to the drawings schematically shown:

1 is a perspective view of two chip carriers each viewed as a chip surface and a connection surface;

2 shows the chip carrier of FIG. 1 with only contacts, conductor paths and via holes shown with edge boundaries, FIG.

3 shows an adapter according to the invention with the chip carrier of FIGS. 1 and 2,

4 is a contact pin array of the adapter of FIG. 3 with a chip carrier;

5 is a perspective view of another adapter according to the present invention;

6 is a plan view of the adapter of FIG. 5 showing respective conductor paths of the adapter;

7 is a finger tester using the adapter according to the present invention,

8 is a plan view of another adapter according to the invention,

9 shows an arrangement of interconnected conductor paths of chip carriers in a very simplified form, and

10 is a perspective view of an adapter having a chip carrier mounted;

The adapter 1 according to the invention for inspecting four chip carriers 2 is shown schematically in a perspective view in FIG. 3. The adapter has an adapter body 3 which in this embodiment is a plastic plate of non-conductive material. The adapter body 3 has several through holes 4 each of which can receive the contact pins 5. The through holes are arranged in the form of two matrices each having 10 × 10 through holes 4. In each case, the distance between the centers between two adjacent through holes 4 is 0.5-1 mm. Thus, the through holes 4 are arranged in a regular, rectangular grid according to a ball grid array (BGA).

At each of the two ends the contact pins 5 have probe tips 6, 7. For the sake of simplicity, the contact pins 5 protruding in a predetermined manner out of the through holes 4 are shown in FIG. 3. In a particular embodiment, the contact pin 5 extends only tens of millimeters above the top surface 8 or bottom surface 9 of the adapter body 3 together with the probe tips 6, 7. Since the contact pin 5 is preferably a so-called spring contact pin made of a spring element, the contact pin 5 can be compressed by the spring means. The contact pin is preferably provided with an antifriction agent in the approximately longitudinal central region to ensure that the contact pin 5 does not fall through the through hole 4.

Contact fields 17 and 18 for contacting the chip carrier 2 with the probe tips 6 and 7 of the matrix of contact pins 5 in either of the two surfaces 8, 9 of the adapter body 3, respectively. Form each.

In this embodiment, this chip carrier 2 is a small circuit board having a chip face 10 and a connection face 11 (Figs. 1 and 2). A small contact pad 12 is formed on the chip surface 10 that forms a ring of four curved segments 13 in plan view. These contact pads 12 are used for bonding an integrated circuit (not shown). From some of these contact pads 12, the conductor path 14 is guided to via holes 15. Typically all or at least substantially all contact pads 12 are connected to via holes 15 by conductor paths 14. In the figures, only a few conductor paths 14 are shown in FIGS. 1 to 4 to simplify the representation. These via holes 15 are formed on the chip carrier 2 in the grid of the ball grid array, and in each case extend from the chip surface 10 to the connection surface 11. On the connection surface 11, via holes 15 form contacts 16, respectively. Via hole 15 is a through hole, for example less than 0.1 mm in diameter, completely coated or filled with an electrically conductive material. In the region of the contact 16, an electrically conductive material forms the contact pad 12. The diameter of the contact 16 is considerably larger than the length or width of the contact pad 12 on the chip surface 10, for example reaching 0.5 mm. Since the contacts 16 are arranged in a regular grating (BGA grating) as described above, the contacts are spaced far more widely than the contact pads 12 of the chip face 10, thus making contact with the adapter easier.

Due to the high contact density on the chip surface, the chip carriers are generally formed of multi-layer circuit boards. For this reason, in the case of such a chip carrier, the via hole does not always extend through the whole of the chip carrier. 1 to 4 are schematically simplified for this.

A general feature of chip carriers is that all or at least a plurality of conductor paths are guided from the chip surface to the connection surface. In this embodiment, the connection from the chip surface to the connection surface is achieved by via holes. Only in the case of complex chip carriers, a conductor path is provided which is connected only to two contacts on the chip face and is not guided to the connection face. However, the number of such conductor paths is lower than the conductor paths guided from the chip surface to the connection surface.

To inspect such a chip carrier 2, the chip carrier is arranged at the contacts 16 on the set of probe tips 6 which respectively form the contact field 17. Another chip carrier 2 is arranged at the contacts 16 on the probe tip 7 forming another contact field 18. Since the probe tips 6 and 7 of the contact fields 17 and 18 are electrically connected to each other in pairs via the contact pins 5, the contacts 16 of the two chip carriers 2 are also electrically connected to each other in pairs. (FIG. 4).

On the adapter 1 of the present embodiment, two pairs of chip carriers 2 can be mounted, and the contacts 16 of the opposing chip carriers 2 are electrically connected in pairs with each other.

For inspection, an adapter 1 and a chip carrier 2 are mounted on the finger tester 20 (FIG. 7). The finger tester 20 has several tester fingers 21, and a test electrode 22 is integrally formed on each tester finger. The test electrode 22 is connected to the electronic evaluation device. The tester finger 21 can move parallel to the top and bottom surfaces of the adapter with the aid of a slider 23 parallel to the surface of the chip carrier 2, such that the electrodes are in contact pads 12 of the chip carrier 2. ) May be contacted. Such a finger test has, for example, sixteen finger tests 21, each eight up and down the adapter 1 so that the chip carrier 2 on both sides of the adapter 1 can be contacted. Each test finger 21 is fixed to a slider 23 that can be moved to a plane parallel to the surface of the adapter 1. Sliders 23 are each provided with actuating cylinders 24 arranged vertically, by which the test fingers 21 can be rotated about a vertical axis. The test finger 21 also includes a moving device, by which the test finger 21 can be moved at right angles to the surface of the chip carrier 2, such that the contact pads 12 have a test electrode 22. Can be contacted by

By means of a pair connection of the contacts 16 by an adapter 1, for example, in each case two conductor paths 25 of two chip carriers 2 are electrically connected to one another and an embodiment of the invention ( 3 and 4 together with the electrical connection of the adapter with one of the contact pins 5 to form a test net. In each case, the end of this test net is formed by the contact pad 12. Since the conductor path 25 of the chip carrier is largely unbranched, such test nets typically have only two ends. These two ends and corresponding contact pads 12 may be contacted simultaneously by one of the test electrodes 22. By means of the test electrode 22, once the measurement current is applied to the test net and the resistance of the test net is determined, it can be determined from this measurement whether the two conductor paths 25 of the two chip carriers 2 are disconnected. have. This represents a conventional resistance measurement for inspecting disconnection. Thus, through the coupling of two chip carriers by an adapter, disconnection in each case simultaneously on the conductor path 25 and thus on the two conductor paths 25 measured once on both chip carriers. Can be checked The adapter itself is not connected to the electronic evaluation device. During the test operation, the test net is connected to the electronic evaluation device only through the test finger 21.

In the short-circuit test by resistance measurement, in each case, adjacent test nets are contacted by the test electrode 22 and the resistance between these adjacent test nets is measured. Here, in each of the two cases, two pairs of conductor paths 25 are examined simultaneously.

With the adapter 1 according to the invention, it is possible to inspect the chip carriers with a conventional test finger, wherein at least two chip carriers are simultaneously tested in one test operation. The throughput of the chip carrier under test is comparable to that of the particular test device described earlier with both the adapter and also the test finger.

Another embodiment of the adapter according to the invention is shown in FIGS. 5 and 6. This adapter 1 has a laminated circuit board as the adapter body 3. On the surface of the adapter body 3, instead of the probe tips 6 and 7 described above, contact nipples 26 and 27 made of an electrically conductive rubber material are provided as contact elements. These contact taps 26 and 27 form two contact fields 17 and 18 in turn, and the contact taps 26 and 27 in the contact field are in each case the contact 16 of the chip carrier 2 under test. In each case, each contact faucet 26 is in contact with the contact 16. In this embodiment, the contact faucets 26 and 27 of the two contact fields 17 and 18 are arranged in a matrix according to the BGA.

The contact nipples 26 of the contact field 17 are connected in pairs to the contact nipples 27 of the contact field 18 via the electrical conductor path 28, ie in the same row and the same column of the matrix. Preferably, in each case, the contact faucets provided at the same position in each of the contact fields 17, 18 are electrically connected to each other, for example the lower left end of FIG. 6 in each case. This pair connection of the contact elements of the contact fields 17, 18 results in the same type of conductor path 14 of the chip carrier, in each case, when two identical chip carriers are arranged in the same arrangement on the contact fields 17, 18. Has the effect of being electrically connected to each other. This is, for example, because the conductor paths 14 of the same type are examined together in each case in order to carry out an open circuit inspection, ie in each case the corresponding contact pads 12 of the chip carrier 2 are contacted, Simplify the test algorithm that can be considered.

In addition to the conductor paths 28 for pairing the contact elements of the contact fields 17 and 18, the adapter has one or more conductor paths 29 which serve as antennas for field measurement processing (FIG. 6). . The field measurement procedure is described in detail in EP 508 062 B1 and EP 772 054 A2. In order to carry out the field measurement procedure, a non-uniform electric field is generated by the antenna 29, and the resulting potential in the test net is then drawn from each test net by the test finger 21. Comparison with another test net's potential and / or reference value can determine if the test net is shorted. Thus, this field measurement allows a short test of the test net with only one sample measurement from that test net.

In the case where admittance can be used as a reference for each test net, this field measuring method, in accordance with the method according to EP 0772 054 A2, also requires only one test sample from the test net. Can be determined by.

Since the test net comprises at least two conductor paths of two chip carriers 2 in each case, at least two conductor paths are simultaneously examined in one measurement. Since only one test sample is required for the disconnection and / or short-circuit inspection with the field measurement method, several conductor paths are simultaneously examined for each test sample. By this means, the throughput of the chip carrier 2 under test is significantly increased in comparison with a known specific device for chip carrier inspection.

The adapter according to the invention is described in detail with reference to the embodiment in which the contact elements of the contact fields 17, 18 are in each case connected in pairs. In the case of chip carriers in the form of circuit boards, it is a manufacturing practice to provide several chip carriers on one circuit board, each of which represents a so-called use. For example, five or ten such uses may be provided on one circuit board. In these cases, circuit board manufacturers often require resistance measurements to check for disconnections, and in practice the most preferred method includes resistance measurements to check for disconnections and field measurements to check for shorts, so that each use contact It would be appropriate to provide an adapter which is assigned to the field and in which the corresponding contact elements of the respective contact fields are all electrically contacted together in the manner described above. It is possible to inspect multiple conductor paths simultaneously on each use or chip carrier, so that in order to check for disconnection, all the end points of the test net must be contacted at least once, and in order to check for a short circuit, each test net is inspected only once. Should be.

FIG. 8 shows another adapter of similar design to the adapter shown in FIGS. 5 and 6. This adapter 1 has a circuit board as the adapter body 3. A contact nipple 30 made of an electrically conductive rubber material is arranged on the surface of the adapter body 3 as a contact element. These contact taps form one contact field 31. Since the contact taps are respectively located in accordance with the arrangement of the contacts 16 of the chip carrier 2 under test, the contacts 16 can be contacted by the respective contact taps 30. In this embodiment, the contact nipples 30 are arranged in a 10 × 10 matrix according to the BGA.

In this embodiment, in each row of the matrix, the contact nipples 30 are connected to each other by conductor paths 32. In this embodiment, the conductor path 32 is in contact with the contact faucet 30, which in each case is filtered one in one of the rows. In each case, two conductor paths 32 are provided for a row of contact nipples. Such a conductor assembly can be formed directly on the surface of a simple circuit board, and no stacked circuit board is needed for this purpose.

In this embodiment, in each case, five contact faucets 30 are electrically connected to each other. This means that the five conductor paths of the chip carrier 2 are also electrically connected to each other, as long as all the contacts 16 are intended to be connected by the conductor path 14.

This adapter can be used for the inspection of the chip carrier 2 with the contacts 16 on the connecting face 11 arranged in a standardized grid arrangement. This means that the adapter can be used for another chip carrier 2 as long as the grid pattern of the contacts 16 matches the arrangement of the contact tap 30. This is, in principle, for the chip carrier so that the chip carrier is inspected on the finger tester as long as the arrangement of the contacts 16 of the chip carrier 3 is standardized and is consistent with the arrangement of the contact tap 30 of the adapter 1. That means you don't have to design a new adapter.

Of course, the contact faucets 30 are also interconnected in other ways, for example, in which the contact faucets in different rows are electrically connected to one another, or in such a way that the number of contact faucets electrically connected to one another is greater or smaller. You can.

In addition, several contact fields 31 on the adapter, in which contact elements (contact taps 30 in this specification) are electrically connected to each other, and individual contact elements in other contact fields are also electrically connected to each other. May be advantageous. For example, in the case of the adapter shown in FIG. 8, individual conductor paths 32 may be electrically connected to corresponding conductor paths in corresponding other contact fields.

FIG. 9 schematically shows in a very simplified form the conductor paths of the chip carriers 2 which are respectively guided from the chip surface to the connection surface. By way of the adapter of Fig. 8, the conductor paths filtered by one of the conductor paths in a row are electrically connected. Thus, two test nets 33 and 34 are formed in rows, respectively. Thus, between two adjacent conductor paths of the test net, in each case there is another conductor path of the other test net. This ensures that two adjacent conductor paths of the test net cannot form a short without creating a short with other conductor paths of another test net arranged between these two conductor paths. This is described by the Shielded Adjacency Criterion, because each individual conductor path is blocked by adjacent conductor paths from the nearest conductor path of the same test net. Using the test net formed in this manner, it ensures able to be detected by the short circuit test between any of the test net associated to a short circuit having a plurality of conductive paths, each conductive path between the chip carrier. Moreover, the interconnection of many of these conductor paths significantly reduces the number of test nets and thus significantly reduces measurement operations. In the adapter according to FIG. 8, in each case five conductor paths are connected to each other. Of course, many different conductor paths can also be connected to each other, so that up to 50 conductor paths can be sensed for interconnection. Ideally, because all conductor paths are connected to form only two test nets, only one measurement should be made to check the chip carrier for short circuits.

 In a simpler embodiment, the longer, branched conductor paths on the chip carrier, e.g., to connect only the longer conductor paths to each other, allowing different conductor paths to be examined separately for one large test net. For example, it may be advantageous if the intention is to provide power or ground conductor paths. Then, for example, a large test voltage can be applied to this test net once, and all other conductor paths can be checked for this large test voltage in a short period of time. In this connection, reference is made to DE 197 00 505 A1.

FIG. 10 shows another adapter according to the invention which is similar in design to the adapter shown in FIG. 3. Thus, identical parts are given the same reference numerals.

The adapter 1 has four matrices, each with 10 x 10 through holes 4 each holding a contact pin 5 in each case. Thus, eight contact fields are formed to hold eight chip carriers 2. An aerial board 35 is adjacent to each adapter body 3, and a cable 36 for applying an electric potential to an antenna formed on the aerial board is provided on each aerial board. The aerial board 35 has an associated through hole for the passage of the contact pin 5. The antenna can in fact only be isolated as a contact layer that extends over the entire aerial board 35, the area of the through-hole for receiving the aerial board 35 may have, contact pins (5) to be formed on. However, the antenna can also have a complicated structure.

Also provided are two alignment plates 37 having the same external dimensions as the adapter body 3 and the aerial board 35. These alignment plates 37 each have four openings 38 that are somewhat smaller than the outline of the chip carrier 2 under test. The opening 38 is slightly undercut, so that a continuous boundary web 29 projecting inward is formed in each opening 38. A chip carrier can be inserted in each opening 38, with the end of the chip carrier fitted in each case with respect to the boundary web 39.

The alignment plate 37, the aerial board 35 and the adapter body 3 have screw connection means 41, ie corresponding through holes 40 with appropriate screws and nuts, thereby aligning the plate 37. And the adapter body and the aerial board 35 located between them are fixed together to form a unit, while each chip carrier is pressed on the corresponding contact field by the alignment plate 37.

The screw connection means 41 represents a clamping device. Apparently these clamping devices are evenly distributed over the surface of the adapter 1, so that a uniformly distributed load is applied to the adapter 1.

This adapter, to which the chip carrier is fixed by the alignment plate 37, can be mounted and inspected as a unit in the finger tester. The finger tester itself does not need any additional fixture to secure the adapter and chip carrier.

Fast-acting clamp-action clamping elements may also be used instead of the screw connection means 41 described above.

Of course, it is possible to provide, instead of the position fixing device consisting of alignment plate 37 and the screw connecting means 41 formed directly on the adapter, the position holding device of the press (press) type having the pressure plate corresponding to the finger tester.

In securing the conductor assembly to the adapter, considerable force must be applied, so that only a part of the conductor assembly under test can be fixed and aligned with the adapter, and another group of conductor assemblies can be advantageously fixed and inspected sequentially. have. This applies in particular to the inspection of several conductor assemblies, called uses, formed on one circuit board, as this can entail significant physical problems, as it involves a great force to fix all the uses at the same time. Thus, in the inspection of a circuit board having several uses, when two clamping beams are provided instead of the alignment plate, each of which is arranged adjacent to both sides of a row of uses on the circuit board and fixed to the adapter body, It may be advantageous to secure only one row of uses to the adapter.

Another method of inspecting a circuit board with many uses provides an adapter to check only one or a few uses. That is, this adapter has only one or few contact fields. The adapter is pressed by a suitable device to the surface of the circuit board which can be contacted by the adapter and the associated measuring operation is carried out. After this measurement operation, the adapter is moved away from the circuit board by a short distance from the circuit board to another use and pressed against this use. Then another test measurement operation can be performed. Thus, the adapter is moved in each case between each use or between a few groups of uses.

Within the scope of the present invention, in particular, instead of the antenna provided in the adapter, a conductor path formed on the chip carrier can of course be used as the antenna. This applies in particular when the chip carrier has a larger, branched conductor path, for example a power supply or a ground conductor path.

The adapter according to the invention has been described with the aid of an embodiment for the inspection of chip carriers. However, the adapter according to the invention is not only arranged very close to each other as well as inspection of the chip carrier, but can be used for inspection of any kind of conductor assembly with contacts on one side, for example at least 0.5 mm apart. The contacts on the other side may be formed in any arbitrary manner. The contacts are particularly small and can be close to each other, because these contacts can be contacted by the test finger without difficulty. With the adapter and finger test according to the invention, it is also possible to inspect chip carriers with three-dimensional contours in the area of the chip surface.

The invention can be summarized as follows:

The present invention relates to an adapter for inspecting a conductor assembly, in particular for inspecting a chip carrier. This conductor assembly is not arranged at high density on one surface and has contact elements with a minimum spacing of, for example, 0.5 mm. The adapter has at least two contact fields, each with a set of contact elements, and together with the contact elements of the contact field, in each case can be contacted with contacts in which one conductor assembly is not arranged very closely. Since each contact element in one of the contact fields is electrically connected to the contact element of another contact field, the conductor paths of the two conductor assemblies can be electrically connected to each other and simultaneously examined.

Reference Number List

1: adapter 22: test electrode

2: chip carrier 23: slide

3: adapter body 24: working cylinder

4: through-hole 25: conductor path

5: contact pin 26: contact tap

6: probe tip 27: contact tap

7: probe tip 28: conductor path

8: surface 29: antenna

9: surface 30: contact tap

10: chip face 31: contact field

11: connection surface 32: conductor path

12: contact pad 33: test net

13: curved segment 34: test net

14: Conductor path 35: Aerial board

15: via hole 36: cable

16: contact 37: alignment plate

17: contact field 38: opening

18: Contact Field 39: Perimeter Web

19 40: Through Hole

20: finger tester 41: screw connection means

21: test finger

Claims (29)

Adapter for inspecting one or more conductor assemblies (2) with multiple conductor paths in a finger tester, The conductor assembly has one surface 11 provided with contacts 16 arranged at least at predetermined intervals from the nearest contact so that one surface of the conductor assembly can be contacted by an adapter, The adapter 1 has at least one contact field 17, 18 with a set of contact elements 6, 7; 26, 27 and the contact elements 6, 7 of the contact field 17, 18. 26 and 27 are arranged in a pattern according to the contact 16 of the conductor assembly, The contact elements 6 and 26 are combined with each other contact element 7 and 27 such that the conductor path of the conductor assembly is combined into a plurality of test nets having at least one contact on at least one side not contacted by an adapter. Adapter for inspecting one or more conductor assemblies, in which case they are electrically connected. The method of claim 1, Wherein said test net has at least two contacts on the face of the conductor assembly not contacted by said adapter. The method according to claim 1 or 2, The adapter 1 comprises at least two contact fields 17, 18 each having a set of contact elements 6, 7; 26, 27. At least some of the contact elements 6; 26 for one of the contact fields 17 are in one case electrically connected with one contact element 7; 27 of another contact field 18. Adapter for inspecting conductor assemblies above. The method of claim 3, wherein Adapter for inspection of at least one conductor assembly, characterized in that all the contact elements (6; 26) of the contact field (17) are paired with the contact elements (7; 27) of the other contact field (18). The method according to claim 3 or 4, The contact elements 26, 27 of the individual contact fields 17, 18 are in each case another contact field 18 at a point where the contact element 26 of the contact field 17 is in the contact field 17. Adapter for inspection of at least one conductor assembly, characterized in that it is connected together to be electrically connected to the contact element (27) of the contact field (18) at a corresponding point of The method according to any one of claims 1 to 5, Adapter for inspection of at least one conductor assembly, characterized in that the contact element (30) of the contact field (31) is electrically connected to another contact element (30) of the contact field (31). The method of claim 6, At least one conductor assembly inspection adapter, wherein the contact elements are electrically connected in pairs with each other. The method according to any one of claims 1 to 3 or 6, A plurality of electrical contact elements are connected to it, to be inspected in the inspection of the adapter for a conductor of one or more conductor assemblies are a number of conductor paths in the assembly, characterized in that connected to form a test net finger tester with each other in the contact field. The method according to any one of claims 1 to 8, The conductor assembly is a chip carrier having a connection surface 11 for connecting to another conductor assembly and a chip surface 10 provided with a contact 12 for connecting to an integrated circuit, the contacts on the connection surface being connected by an adapter. Adapter for inspection of at least one conductor assembly characterized in that it can be contacted. The method according to any one of claims 1 to 9, Adapter for inspection of at least one conductor assembly, characterized in that the contact element (6,7) is in each case represented by the tip of the contact pin (5). The method according to any one of claims 1 to 9, The at least one conductor assembly inspection adapter, characterized in that the contact element (26, 27) is in the form of a nipple of an electrically conductive rubber material. The method of claim 10, The tip 6 at one end of one of the contact pins 5 represents in each case one of the contact elements of one contact field 17 and the tip at the other end of the contact pin 5. 7) adapter for inspecting one or more conductor assemblies, characterized in that it represents one of the contact elements of another contact field (18). The method according to any one of claims 1 to 12, The adapter (1) has at least one conductor assembly inspection adapter, characterized in that the conductor path (28) has an adapter body (3) provided to electrically connect the contact elements to each other. The method according to any one of claims 1 to 13, Adapter for inspection of at least one conductor assembly, characterized in that the contacts (16) which can be contacted by an adapter are spaced at a distance of at least 0.5 mm and preferably 1 mm. The method according to any one of claims 1 to 14, Adapter for inspection of at least one conductor assembly, characterized in that said contact (16) which can be contacted by an adapter is at least 0.5 mm in diameter. The method according to any one of claims 1 to 15, At least one conductor assembly inspection, characterized in that said contacts (16) which can be contacted by an adapter are arranged in a regular grid, for example a ball grid array. The method according to any one of claims 1 to 16, At least one conductor assembly inspection, characterized in that it has an antenna (29) which creates a non-uniform electric field. The method according to any one of claims 1 to 17, The adapter (1) is one or more conductor assembly inspection adapters, characterized in that in each case there is a contact field (17, 18) on opposite sides to hold one conductor assembly. The method according to any one of claims 1 to 18, The adapter (1) is one or more conductor assembly inspection adapter, characterized in that it has a positioning device for fixing the at least one conductor assembly to the adapter (1). The method of claim 19, The positioning device has an alignment plate which can be fixed to the adapter body by a fastening device, and the positioning device is provided with at least one opening which is somewhat smaller than the contour of the conductor assembly under test, so that the conductor assembly Is arranged between the adapter body and the alignment plate in the opening area, the face of the conductor assembly 2 fixed to the adapter and not in contact with the adapter body can be connected Adapter for inspecting conductor assemblies above. The method of claim 20, The fastening device is one or more adapter assembly inspection adapter characterized in that the screw connection form. The method of claim 20, Wherein said fastening device is in the form of a quick-action clamp. At least one conductor assembly 2 having contacts on one side thereof which can be contacted by the adapter is brought into contact with the adapter 1 and the contact elements 6, 7; 26, 27 in the contact field of the adapter 1. ) Is in electrical contact with the corresponding contact of the conductor assembly 2, The unit with the conductor assembly 2 and the adapter 1 is arranged in a finger tester such that the adapter 1 is not directly connected to the electrical evaluation device, The contact 12 of the conductor assembly, which is not on the side contacted by the adapter by means of a test finger 21, to check the conductor path 14 of the conductor assembly 2 for short circuits and / or breaks A method for inspecting conductor assemblies in a finger tester by means of an adapter means according to claim 1. The method of claim 23, wherein Conductor assembly inspection method by the adapter means, characterized in that the conductor path (14) of the conductor assembly (2) is inspected for disconnection. The method of claim 23, wherein Conductor assembly inspection method by the adapter means, characterized in that the conductor path (14) of the conductor assembly (2) is inspected for disconnection by the field measurement method. The method according to any one of claims 23 to 25, Conductor assembly inspection method by the adapter means, characterized in that the conductor path (14) of the conductor assembly (2) is short-circuited by resistance measurement. The method according to any one of claims 23 to 25, Conductor assembly inspection method by the adapter means, characterized in that the conductor path (14) of the conductor assembly (2) is short-circuited by a field measuring method. The method of claim 25 or 27, A method for inspecting a conductor assembly by means of adapters, characterized in that an adapter (1) having an integrated antenna (29) is used to carry out the field measuring method. The method according to any one of claims 25, 27 or 28, In each case, one conductor path (14) of the conductor assembly (2) under test is used as an antenna (29) to carry out the field measuring method.