System for testing semiconductor components

What is claimed is:

1. A system for testing a semiconductor component comprising:

a test board in electrical communication with test circuitry;

a carrier configured to hold the component comprising a base comprising a plurality of first contacts, and an interconnect on the base comprising a plurality of contact members in electrical communication with the first contacts configured to establish temporary electrical connections with a plurality of second contacts on the component; and

a socket on the test board comprising a plurality of electrical connectors in electrical communication with the test circuitry configured to electrically engage the first contacts, and a mating camming member configured to move the electrical connectors to permit insertion of the base into the socket with a zero insertion force, or removal of the base from the socket with a zero removal force,

the socket and the test board configured for use with a second base and a second interconnect for testing a second component different than the component.

2. The system of claim 1 wherein the contact members comprise sloped indentations configured to align the component to the interconnect.

3. The system of claims 1 further comprising an alignment member on the base having an opening configured to engage a periphery of the component to align the component to the interconnect.

4. The system of claim 1 wherein the contact members comprise projections at least partially covered with conductive layers configured to penetrate the second contacts.

5. The system of claim 1 wherein each contact member comprises at least two projections at least partially covered with a conductive layer and configured to retain a second contact.

6. The system of claim 1 further comprising a first polymer layer on the base having a first opening configured to contact an edge of the component to provide coarse alignment, and a second polymer layer on the interconnect having a plurality alignment openings configured to contact the second contacts to provide fine alignment.

7. The system of claim 1 wherein the contact members comprise indentations in a substrate of the interconnect with edges configured to penetrate the second contacts.

8. The system of claim 1 wherein the contact members comprise stepped indentations in a substrate of the interconnect with at least two edges configured to penetrate the second contacts.

9. The system of claim 1 wherein the component comprises an element selected from the group consisting of bare semiconductor dice and semiconductor chip scale packages.

10. The system of claim 1 wherein the electrical connectors are configured to exert a spring force for moving the camming member.

11. A system for testing semiconductor components comprising:

a test board in electrical communication with test circuitry;

a plurality of carriers configured to hold the components on the test board, each carrier comprising a base comprising a plurality of first contacts, an interconnect on the base comprising a plurality of contact members configured to electrically engage a plurality of second contacts on a component; and

a plurality of sockets on the test board, each socket comprising a plurality of electrical connectors in electrical communication with the test circuitry and configured to electrically engage the first contacts, and a camming member configured to move the electrical connectors to allow insertion of the base into the socket with a zero insertion force, or removal of the base from the socket with a zero removal force,

the interconnect and the base customized for a particular type of component similar to the component while the test board and the socket can be used with different types of components different than the component.

12. The system of claim 11 wherein the second contacts comprise bumped contacts and the contact members comprise indentations with edges configured to penetrate the bumped contacts.

13. The system of claim 11 wherein the second contacts comprise bumped contacts and the contact members comprise stepped indentations with multiple edges for engaging the bumped contacts.

14. The system of claim 11 wherein the alignment member comprises a first polymer layer having a first opening configured to contact an edge of the component to provide coarse alignment, and a second polymer layer having a plurality alignment openings configured to contact the second contacts to provide fine alignment.

15. A system for testing a semiconductor component comprising:

a test board in electrical communication with test circuitry;

a carrier for holding the component comprising a base comprising a plurality of external contacts, an interconnect on the base comprising a substrate, a plurality of contact members on the substrate in electrical communication with the external contacts for electrically engaging contacts on the component, and a force applying mechanism for biasing the component against the interconnect; and

a socket on the test board comprising a plurality of electrical connectors in electrical communication with the test circuitry configured to electrically engage the external contacts on the base, and a camming member configured to manipulate the connectors to permit insertion of the base into the socket with a zero insertion force, or removal of the base from the socket with a zero removal force, the electrical connectors configured to exert a spring force for moving the camming member,

the socket and the test board configured for use with a second base and a second interconnect for testing a second component different than the component.

16. The system of claim 15 wherein the interconnect comprises a photomachineable ceramic.

17. The system of claim 15 wherein electrical connections between the base and the interconnect comprise an element selected from the group consisting of wire bonds, flex circuit bonds, and mechanical electrical connectors.

18. The system of claim 15 wherein the force applying mechanism comprises a bridge clamp attached to the base and a spring attached to the bridge clamp.

19. The system of claim 15 wherein the component comprises an element selected from the group consisting of bare semiconductor dice and semiconductor chip scale packages.

20. The system of claim 15 further comprising an alignment member on the interconnect or the base having an alignment opening configured to engage an edge of the component.

21. The system of claim 15 wherein the alignment member comprises a first polymer layer deposited on the interconnect or the base having a first opening configured to contact an edge of the component to provide coarse alignment, and a second polymer layer deposited on the interconnect or the base having a plurality alignment openings configured to contact the contacts on the component to provide fine alignment.

22. The system of claim 15 wherein the interconnect comprises a Photosensitive ceramic.

23. A system for testing a semiconductor component comprising:

a test board in electrical communication with test circuitry;

a carrier configured to hold the component on the test board, the carrier comprising an interconnect comprising a Photosensitive ceramic substrate and a plurality of contact members on the substrate configured to electrically engage a plurality of contacts on the component; and

a socket on the test board configured to mount the carrier to the test board, the socket comprising a plurality of electrical connectors in electrical communication with the test circuitry configured to establish electrical communication between the contact members and the test circuitry, and a mating camming member configured to move the electrical connectors to permit insertion of the base into the socket with a zero insertion force, or removal of the base from the socket with a zero removal force,

the socket and the test board configured for use with a second base and a second interconnect for testing a second component different than the component.

24. The system of claim 23 wherein the carrier comprises a base comprising a plurality of second contacts in electrical communication with the contact members and configured for electrical engagement by the electrical connectors.

Description Submit all comments and votes

FIELD OF THE INVENTION

This invention relates generally to semiconductor manufacture, and more particularly to an improved system and method for testing semiconductor components including bare dice and chip scale packages.

BACKGROUND OF THE INVENTION

Semiconductor components, such as unpackaged dice and chip scale packages, must be burned-in and tested prior to use in electronic equipment. One test procedure involves placing one or more semiconductor components in a test carrier. The carrier provides a container for handling and electrically connecting the components to a testing apparatus. The testing apparatus can include test circuitry adapted to transmit and analyze test signals from the components held within the carrier. The carrier and testing apparatus form a test system.

One requirement of carriers for testing semiconductor components, is the ability to make temporary electrical connections with the components. The temporary electrical connections permit test signals to be transmitted to the integrated circuits contained on the components. One type of carrier includes an interconnect adapted to make temporary electrical connections with contacts on the components. The contacts on unpackaged dice are typically flat or bumped bond pads formed on faces of the dice. The contacts on chip scale packages are typically solder bumps formed on substrates bonded to the faces of the dice.

These contacts on the components can be in the form of small, densely-packed members. For example, chip scale packages can include a hundred or more solder bumps having a diameter and spacing of several mils or less. Unpackaged dice can include bond pads having a width and spacing of several mils or less. The interconnect of the carrier must be able to make separate electrical connections to each contact without shorting or excessively damaging the contact.

The carrier must also include external contacts adapted to make electrical connections with the test apparatus. These externals contacts on the carrier must have a size and density corresponding to the size and density of the contacts on the components under test. In addition, the external contacts must be able to perform reliably in a production environment over an extended period of time.

Another consideration is the interface of the external contacts with the test apparatus. The test apparatus must be able to efficiently handle and electrically connect to a large number of individual carriers. The physical and electrical interface of the carriers and the test apparatus affects the performance of the test system to a large degree.

The present invention is directed to a system including a carrier with a dense array of external contacts and a socket adapted to physically and electrically connect to the external contacts.

SUMMARY OF THE INVENTION

In accordance with the present invention, an improved system and method for testing semiconductor components are provided. The system includes carriers for holding the components, and a test apparatus adapted to transmit test signals to the carriers and to analyze response signals from the components under test. The test apparatus includes a test board, and a plurality of separate sockets mounted to the test board, in electrical communication with test circuitry. Each socket is configured to physically and electrically engage a single carrier. The sockets include rows of electrical connectors for electrically contacting contacts on the carriers, and camming members for manipulating the electrical connectors to allow insertion and removal of the carriers. The electrical connectors and camming members allow the carriers to be inserted into the sockets with a zero insertion force.

The carriers include bases for holding multiple components, and multiple interconnects each adapted to establish temporary electrical communication with an individual component. The carrier bases also include the contacts which electrically contact the electrical connectors on the sockets mounted to the test board. The electrical interface between the contacts on the carrier bases, and the interconnects mounted to the carrier bases, can be wire bonding, flex circuit bonding or mechanical-electrical connectors.

In addition to the bases and interconnects, the carriers also include a force applying mechanism for biasing the components against the interconnects. The force applying mechanism include bridge clamps attachable to the carrier bases and metal or elastomeric spring members. In an illustrative embodiment the bases comprise ceramic with plated external contacts adapted to electrically engage electrical connectors on sockets mounted to the test board.

In accordance with the method of the invention the sockets can remain electrically connected to the test board. In addition, the carrier bases can remain electrically connected to the sockets with the interconnects thereon. During a test procedure, the components can be optically or mechanically aligned with the interconnects, and placed in physical and electrical contact therewith. Test signals can then be transmitted through the test board, sockets, carrier bases and interconnects to the components. As long as the same types of components are being tested, the carrier bases and interconnects can remain mounted to the same sockets on the test board. However, the bases and interconnects can also be easily removed from the sockets, and different bases and interconnects can be substituted for testing other types of components. Accordingly the configurations of the interconnects and carrier bases can be customized for a particular type of component, while the test board and socket configurations remain the same.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view of a system constructed in accordance with the invention;

FIG. 2A is a plan view of a carrier and socket of the system;

FIG. 2B is a cross sectional view of the carrier and socket taken along section line 2B--2B of FIG. 2A;

FIG. 2C is a side elevational view partially cut away of the carrier and socket;

FIG. 3 is a schematic perspective view of a base and interconnect of the carrier illustrating optical alignment of a semiconductor component with the interconnect;

FIG. 4 is a schematic side elevational view of the component and interconnect in the assembled carrier;

FIG. 4A is an enlarged schematic cross sectional view taken along section line 4A--4A of FIG. 4 illustrating engagement of a contact bump on the component with a contact member on the interconnect;

FIG. 4B is an enlarged schematic cross sectional view equivalent to FIG. 4A illustrating engagement of a contact bump on the component with an alternate embodiment contact member on the interconnect;

FIGS. 5A-5D are enlarged schematic cross sectional views equivalent to FIG. 4A of alternate embodiment contact members;

FIG. 6 is a block diagram of steps in the method of the invention;

FIG. 7A is a schematic plan view of an alternate embodiment carrier;

FIG. 7B is a cross sectional view taken along section line 7B--7B of FIG. 7A; and

FIG. 7C is an enlarged cross sectional view taken along section line 7C of FIG. 7B showing an encapsulated wire bonded connection;

FIG. 7D is an enlarged cross sectional view equivalent to FIG. 7C of an alternate embodiment flex circuit connection; and

FIG. 7E is an enlarged cross sectional view equivalent to FIG. 7C of an alternate embodiment mechanical-electrical connection.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, a system 10 adapted to test semiconductor components 12 is shown. In the illustrative embodiment, the semiconductor component 12 can be a bare die or a chip scale package. The system, broadly stated, includes: a test board 14; test circuitry 18 adapted to apply test signals through the test board 14 to the components 12 and to analyze the resultant signals; a plurality of sockets 16 mounted to the test board 14 in electrical communication with the test circuitry 18; and a plurality of carriers 20 adapted to contain the components 12 for testing.

The test board 14 can be formed of an electrically insulating material such as a ceramic, FR-4, glass filled plastic, or polyimides. The test board 14 can include an edge connector 21 electrically connectable to an electrical path 22 to the test circuitry 18. The test board 14 can also include electrical paths in the form of conductive traces or other elements adapted for electrical communication with the sockets 16.

The test circuitry 18 can be configured to test electrical parameters such as input and output voltages, capacitances, and currents for the integrated circuits contained on the components 12. In the case of components 12 having memory devices, the test circuitry 18 can also perform logic tests wherein data storage, retrieval capabilities and response times are measured. The test circuitry 18 can be in the form of conventional test circuitry manufactured by Teradyne, Advancetest, Hewlett Packard and others.

Referring to FIGS. 2A-2C, an individual socket 16 is shown. The socket 16 can be configured to receive the carrier 20 from above with a "zero insertion force". The socket 16 includes a socket base 26 with pin connectors 28 configured to electrically contact mating electrical receptacles (not shown) on the test board 14. The socket base 26 also includes rows of electrical connectors 24 (FIG. 2A) configured to electrically engage contacts 38 (FIG. 3) on the carrier 20. The electrical connectors 24 are in electrical communication with the pin connectors 28. In addition, the electrical connectors 24 are shaped to physically engage a camming member 41. The electrical connectors 24 can be formed of a flexible material such as beryllium copper, or "PALLINEY 7" available from J.M. Ney Company of Hartford, Conn.

Viewed from above, the camming member 41 is shaped like a window frame. The camming member 41 is movable in axially opposite directions as indicated by the double headed arrow in FIG. 2B. The camming member 41 includes a camming surface engageable with portions of the electrical connectors 24, substantially as shown in FIG. 2B. Depression of the camming member 41 towards the socket base 26 moves the electrical connectors 24 outward to

provide clearance for inserting the carrier 20 into the socket 16. This allows the carriers 20 to be inserted into the sockets 16 with a "zero insertion force". With a manual system, the camming member 41 can be depressed by hand. With an automated system, the camming member 41 can be depressed by another actuator (not shown). Once the camming member 41 is released, the electrical connectors 24 provide a spring force for moving the camming member 41 axially upward away from the socket base 26 to its original position. At the same time, the electrical connectors 24 provide a spring force for electrically engaging the contacts 38 (FIG. 3) on the carrier 20.

The socket 16 also includes a support member 30 (FIG. 2B) adapted to support the carrier 20, and limit the axially downward movement of the carrier 20. In addition, the carrier 20 can be removed with a "zero removal force" by depression of the camming member 41 to disengage the electrical connectors 24 from the carrier 20. Other aspects of the socket 16 will become more apparent as the description proceeds.

Still referring to FIGS. 2A-2C, the carrier 20 includes the carrier base 32, and an interconnect 34 mounted to the carrier base 32. The carrier base 32 establishes electrical communication with the socket 16. The interconnect 34 is electrically connected to the carrier base 32 and establishes temporary electrical communication with the component 12. The carrier 20 can also includes a force applying mechanism in the form of a pressure plate 36, a spring 42, and a bridge clamp 44. The force applying mechanism biases the component 12 against the interconnect 34. These components will be described in detail as the description proceeds.

Referring to FIG. 3, the carrier base 32 and interconnect 34 are shown separately. Preferably, the carrier base 32 comprises an electrically insulating material such as ceramic, plastic, photomachineable glass, or FR-4.The carrier base 32 includes patterns of conductors 40 formed on a face surface thereof. The conductors 40 include the contacts 38, which are formed along the periphery of the carrier base 32. Each conductor 40 has an associated contact 38. The contacts 38 are adapted to electrically contact the electrical connectors 24 (FIG. 2B) on the socket base 26 (FIG. 2B). The conductors 40 on the carrier base 32 are adapted for electrical communication with corresponding conductors 48 (FIG. 4A) on the interconnect 34.

The interconnect 34 mounts to the carrier base 32. Bond wires 46 can be used to form separate electrical paths between the conductors 40 on the carrier base 32 and the conductors 48 (FIG. 4A) on the interconnect 34. Alternately these electrical paths can be formed with flex circuit or mechanical-electrical connectors. If desired, an electrically insulating adhesive, such as silicone, can be used to secure the interco