JP3030239B2 - Test head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a test head suitable for use in testing electronic components, especially integrated circuits.

[0002]

2. Description of the Related Art In recent years, characteristic testing of electronic components, especially integrated circuits, has become a very important process element for electronic component manufacturers. In the description of the present invention, an integrated circuit is specifically described, but the present invention is also effective in other electronic component tests. Latest integrated circuit has 100 terminals
, And the test equipment is fundamental to test all of its terminals, so that the test equipment becomes complicated and large in size. Therefore, the test apparatus is divided into several parts to improve the convenience over the life cycle of the test apparatus.

In general, a test apparatus is divided into a test apparatus main body and a test station, and the test station is composed of a kind of intelligent sensor and a device for transporting electronic devices under test. The signal transmitted / received to / from the electronic component to be measured, which is brought into contact with the test terminal (probe) by the transfer device or manually, undergoes primitive operations such as conversion, compression, and expansion in the test head body forming a part of the intelligent sensor. Provided for communication with the test apparatus main body.

[0004] The intelligent sensor is divided into a test head and a prober. The prober mechanically positions the electronic device under test and brings the terminals of the electronic device under test into contact with a measurement probe connected to a provided probe card. By connecting the output terminal of the probe card to the test head, it becomes possible to exchange electric signals between the electronic component under test and the test head. The test head performs the remaining primarily electrical functions. From another point of view, the test apparatus interfaces with the integrated circuit through the output terminal of the prober, converts a test data signal into an electric signal suitable for an electronic device under test (hereinafter referred to as a DUT), and applies the electric signal to the DUT. And a test head that converts electrical signals from the DUT into data signals, and a test apparatus that performs data generation and transmission, reception analysis, communication, and human-machine interface.

There are various configurations of the test head main body.
A switch and a drive circuit for supplying and stopping a signal to each pin of the UT are mainly used. In order to generalize the test apparatus, a test head equipped with an interface circuit equal to the number of DUT terminals for each pin has a weight of several tens of kg and often exceeds 100 kg. In this embodiment, it reaches 135 kg. FIG. 5 shows a front view of such a test station. Test station on floor 5
5 has a prober main body 54 supported by an adjuster 56 and a test head support 57. The test head main body 2 is attached to the support frame 1 and has a bundle of wires (cables) 51 to a test apparatus main body (not shown). The test head main body 2 and the support frame 1 are united and attached to a rotating shaft 58 fixed to the support portion 57, and revolve around the rotating shaft 58 as a central axis. The test head at the position drawn by the solid line in FIG. 5 is an attitude mainly used for testing a wafer or the like, and the position shown by a dotted line is an attitude mainly used for testing a component mounted on a package. is there. FIG. 5 shows the terminal surface 5 of the prober.
3 and the connecting portion 52 of the test head are shown by dotted lines.

FIG. 6 is a plan view of the test station shown in FIG. 5, in which the coupling mechanism between the test head body 2 and the support frame 1 is omitted. The central cylindrical hole 3 is for observing the connection state of the DUT with a microscope. In the test station as described above, since the electrical interconnection between the probe card and the test head is made with minute contacts, their positioning must be sufficiently accurate. In particular, since the probe card terminal surface has an assembly error and is densely arranged circumferentially concentrically with the periphery of the cylindrical hole 3, the accurate connection with the test head is about ± 2 mm in the circumferential direction. Needs to be adjusted.

In the prior art, this adjustment is performed as follows. (A) As disclosed in Japanese Utility Model Application Publication No. 60-109056, a relay terminal plate for receiving a connection contact of a test head is provided, and the relay terminal plate and the probe card are connected by a flexible connection cable called measuring. The method is one of them. (B) In Japanese Utility Model Application Laid-Open Publication No. 62-123568, the connection contact receiving pad of the relay terminal plate is formed in a sector shape to create a margin equal to the adjustment amount. (C) There is also a method of incorporating the interruption terminal plate described in (a) above in the test head body. (D) Further, a method of rotating the entire test head using a so-called test head manipulator or test head positioner is disclosed in U.S. Pat. Nos. 4,527,942 and 4,588,346.

In the above method (a), the electrical length increases due to the measuring portion, the reliability decreases due to the increase in the number of connection points, and D
There is a disadvantage in that the cost increases due to an increase in the number of contact pins and measurement in proportion to the increase in the number of pins of the UT. In the above method (b), the pad becomes large, and the multi-terminal DUT is used.
It interferes with the measurement of In addition, crosstalk between pads is increased, and electrical characteristics are deteriorated.

In the method (c) described above, the internal structure of the test head is greatly restricted and the size of the test head is increased. Further, the method has an unnecessary function for manual measurement and handler measurement performed at the position indicated by the dotted line in FIG. The above method (d) has an advantage that the manipulator can be connected to each of the prober and the handler. However, the manipulator has a high degree of freedom in its movable mechanism, and is expensive and complicated in operation.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to support a test head body in a movable state by a bearing mechanism so that when mounted on a prober, the probe head is automatically and properly positioned by a bearing and a guide block. To solve the problems of the prior art.

[0011]

SUMMARY OF THE INVENTION In a test head according to one embodiment of the present invention, a test head body is connected to a support frame of the test head using a guide block and a bearing. Therefore, the test head body can rotate with respect to the support frame, that is, with respect to the prober. The mutual positioning of the test head and the prober is achieved by providing means for aligning and placing the positioning block provided on the prober with a roller provided on the test head, for example.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A front view and a plan view of a test head according to an embodiment of the present invention coincide with the ranges shown in FIGS. 5 and 6, respectively. The novel part of the plan view of FIG. 6 according to the invention is shown in FIG.

In FIG. 1, the test head penetrates the rotating shaft 58 through the shaft cylinder 4 and is pivotally attached to the support portion 57. The test head main body 2 is rectangular and is connected to the support frame 1 by four bearing mechanisms 5 attached to the four corners ((A), (B), (C), and (D) of FIG. 6). Approximately 4
It can rotate in the range of about °. Such a rotating surface is not essential, but is often mechanically and electrically preferred in configurations where a heavy test head body is coupled to a prober. The bearing mechanism 5 regulates the rotation direction of the test head body with respect to the support frame 1 and guarantees a smooth movement in the allowed direction.

FIG. 2 shows a more detailed structure of the bearing mechanism 5.
Expanded and shown. The guide blocks 27 and 28 are paired cam-shaped metal blocks and are firmly fixed to the test head body 2. The opposing faces of the two guide blocks 27, 28 are parallel to the plane of rotation of the test head and also parallel to each other, and are separated by a distance slightly greater than the diameter of the vertical bearing 22 which engages them. The vertical side surfaces of the guide blocks 27 and 28 are curved surfaces for guiding the horizontal bearing 21 and are cylindrical surfaces perpendicular to an arc centered on the rotation center of the test head main body 2. In Fig. 2, the curved surface is drawn with a bulge.

The vertical bearing 22 and the horizontal bearing 2
1 is rotatably mounted on a bearing mounting block 25, and the bearing mounting block 25 is fixed to the support frame 1. Therefore, the horizontal position of the test head body 2 is regulated by the horizontal bearing 21 and the vertical side surface of the guide block, and the vertical position is regulated by the opposing plane of the vertical bearing 22 and the guide blocks 27 and 28. Is essentially allowed. Due to the tolerances given in the actual bearing mechanism design, other movements are also slightly tolerated. FIG.
FIG. 4 is a side view of the bearing mechanism viewed from a direction perpendicular to the rotation axis of the vertical bearing 22. The detailed positioning of the test head and the process prober in one embodiment of the present invention will be described with reference to FIG.

First, as shown in FIG. 5, the support frame 1 is rotated, and the test head main body 2 is placed on the prober 54.
To facilitate the work, the support frame 1 is attached to the test head body 2
It is common to have a balancer that offsets the weight of Probe terminal surface 53 of prober 54 and test head body 2
Details of the probe connection part 52 are shown in FIG. 7, a wafer under test 78, which is a DUT, is fixed by vacuum suction by a wafer chuck 73 of a prober 54, and is positioned with respect to a probe card 76 by movement of the wafer chuck 73. When the probe 77 provided on the probe card 76 comes into contact with the wafer under test 78, electric signals can be exchanged between the wafer under test 78 and the probe card 76.

As is well known, the wafer chuck 73 is accurately positioned horizontally with respect to a base which provides a position reference for the prober 54. The wafer chuck 73 is controlled to move up and down, and rises only when a test is performed to bring the probe 77 into contact with the wafer under test 78. The probe card 76 is attached to the contact board 75 directly or by a connector mechanism. The contact board 75 is fixedly attached to the ring insert 72 of the prober 54. The ring insert 72 is also placed on a rigid horizontal table (not shown) fixed to a base that provides a position reference for the prober 54, on which only horizontal rotation about the center of the probe card 76 is possible. Is regulated as follows. By rotating the ring insert 72, the probe card 76 is subordinately rotated, and fine adjustment of the positions of the probe 77 and the wafer under test 78 can be performed.

The electrical connection of the probe 77 to the electronic circuit inside the test head main body 2 is obtained by an electrical path to the pin board 71 via the probe card 76, the contact board 75, and the contact probe 74. The contact probe 74 is usually a probe biased by a spring, and absorbs an alignment error in the vertical direction 0 to complete the electrical connection. The mechanical connection of the test head body 2 is made by the legs 10 provided on the test head body 2 and the positioning blocks 82 on the ring insert 72 of the prober.

The positioning block 82 has a V-shaped groove when viewed from the side rotated 90 degrees with respect to the front shown in FIG. A roller 83 is rotatably attached to a bearing 81 attached to the leg 10. When the test head main body 2 is placed on the prober 54, the test head main body 2
Due to its own weight, the roller 83 is automatically aligned with the center of the V-shaped groove of the positioning block 82 while rotating, as shown in FIG. As a result, the desired alignment between the test head body 2 to which the rollers 83 are fixed and the ring insert 72 to which the positioning block 82 is fixed is completed only by placing the test head on the prober. After that, the test head body 2 and the ring insert 72 rotate integrally.

Further, when it is desired to rotate the probe card 76, the ring insert 72 may be rotated. The test head body 2 is provided with the bearing mechanism 5 on the support frame 1.
, Such rotation can be easily performed. In this embodiment, two sets of positioning blocks 82 are used.

[0021]

As described in detail above, the implementation of the present invention provides at least the following advantages. 1) Since the connection between the test head and the blower is simple and there is no deterioration of the electric characteristics, even in the automatic measurement using the prober, the high accuracy measurement similar to the manual measurement or the handler measurement can be performed with high reliability. 2) Even if the number of contact pins of the test head main body 2 increases, the cost of the measuring portion does not increase, and there is no shortage of space, and it is possible to cope with increasing the number of pins of the DUT. 3) Even when the test head body is rotated in the test state, the cost can be increased and the electrical characteristics can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of a test head according to an embodiment of the present invention.

FIG. 2 is a development view of a bearing mechanism of the test head of FIG. 1;

FIG. 3 is an enlarged plan view of a bearing mechanism.

FIG. 4 is an enlarged side view showing a coupling state of the bearing mechanism of FIG. 3;

FIG. 5 is a front view of a test station on which the test head of the present invention is mounted.

FIG. 6 is a plan view of the test station of FIG.

FIG. 7 is a partial side sectional view of the test station of FIG. 5 in a state where a test head and a prober of the present invention are connected to each other to measure a wafer.

[Explanation of symbols]

1: Support frame; 2: Test head body; 3: Cylindrical hole; 4:
Shaft barrel; 5: Bearing mechanism; 10: Leg (of test head body); Horizontal bearing; 22: Vertical bearing;
5: bearing mounting block; 27, 28: guide block; 51: wiring bundle; 52: connecting portion; 53: blower terminal surface; 54: blower; 55: floor; 56: adjuster; 57: test head support portion; Rotation axis; 71:
73: wafer chuck; 74: contact probe; 75: contact board; 76: probe card; 77: probe;
Wafer; 81: bearing; 82: positioning block: 8
3: Roller

Continuation of the front page (56) References JP-A-5-175290 (JP, A) JP-A-63-299353 (JP, A) JP-A-63-301537 (JP, A) JP-A-4-273458 (JP, A) JP-A-2-119235 (JP, A) JP-A-63-114229 (JP, A) JP-A-4-92639 (JP, U) JP-A-6-60143 (JP, U) JP-A 3-73446 (JP, U) JP-A 3-104742 (JP, U) JP-A 60-163743 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/66 G01R 31/26 G01R 31/28

Claims (2)

(57) [Claims] 1. A support frame rotating around a horizontal axis, and a guide block and a bearing provided in the support frame.
A test head main body supported by the support frame in a rotatable state with respect to the roller, a roller and a positioning block for aligning and mounting the test head main body on a ring insert of the prober
And a click, to the support frame wherein the said ring insert and the test head body are integrated by the aligning placed
Test head having the features that it is rotatable for. 2. The test frame according to claim 1, wherein said support frame is rectangular, and said test head body is provided with said guide block and supported by engaging said guide block with bearings provided at four corners of said support frame. test head according to.