JPH04326539A - Probe equipment - Google Patents

Abstract

PURPOSE:To obtain a probe equipment excellent in durability, maintainability and cost which realize superior electric connection stably and surely and enable inspection with high reliability. CONSTITUTION:A probe pad 22 is arranged at a position facing a probe pin 12 on the upper surface of an inspection board 20, on the lower surface of which an electrode bump 24 is arranged at a position facing an electrode pad 42 on a semiconductor wafer 40. Each electrode bump 24 is connected with each probe pad 42 via a through hole 26 and a printed wiring 28. When a semiconductor wafer 40 is pressed against the inspection board 20, pressure conductive rubber 32 between each electrode pad 42 and each electrode bump 24 is turned into a conduction state, and a pin 12 A of each probe pin 12 is moved upward opposing a compression coil spring 12B. Thereby the pressing force from the side of semiconductor wafer 40 is received.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe device used for inspecting semiconductor chips provided on a semiconductor wafer.

0002

2. Description of the Related Art In the manufacturing process of semiconductor integrated circuits, the electrical characteristics of a large number of semi-finished semiconductor chips formed on a semiconductor wafer are inspected to distinguish good chips from defective chips. In such testing, a probe device is used to establish electrical connection between the semiconductor chip to be tested and the tester.

In a typical conventional probe device, an electrically insulating support ring is attached to a window formed in the center of a printed circuit board, and the tips of the probe needles are arranged so that they overlap with the electrode pad rows inside the window. It has a structure in which a large number of probe needles are arranged radially on a support ring, and an electrical connection with the test object is established by bringing each tip of the probe needle into contact with each electrode pad of the chip under test. I have to. Such radiation probe-type equipment is used to test semiconductor chips that have electrode pads arranged around the chip periphery, but it is also used to test VLSI chips that have a large number of electrode pads arranged in a matrix over the entire chip surface. cannot be used.

[0004] For such high-density electrode pad patterns, a vertical probe type device is used in which probe needles are attached perpendicularly to the substrate. This vertical probe type device has two methods: one in which a wire-shaped probe needle is implanted directly into the substrate, and the other in which a commercially available single probe with an axially movable probe needle is implanted in a predetermined position on the substrate. There are also types that fit into the socket.

[0005]

[Problems to be Solved by the Invention] Conventional probe devices, whether the above-mentioned radiation probe type or vertical probe type, bring an extremely thin probe needle into contact with a small-diameter electrode pad on a semiconductor chip. Therefore, if the inspection is repeated several times, the probe needle tends to become loose or deformed, making replacement and repair cumbersome and costly.

The present invention was made in view of these problems, and has excellent durability, maintainability, and cost efficiency.
Another object of the present invention is to provide a probe device that enables highly reliable inspection and measurement.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the probe device of the present invention has one plate surface on which electrodes are respectively arranged at predetermined positions corresponding to a plurality of electrode pads of an object to be inspected; a test plate having a second plate surface on which a plurality of probe pads are discretely arranged to be electrically connected to each electrode on the one plate surface in a one-to-one relationship via through holes; A plurality of probe pins for elastically press-contacting a pressurized conductive member provided on one surface of the test plate and a probe pad on the other surface of the test plate with substantially uniform pressure, respectively. The configuration includes means.

[0008]

[Operation] When the inspected object and the inspection plate are aligned and pressed against each other, the inspected object is brought into pressure contact with the pressurized conductive member, and each electrode pad and each electrode of the inspected object are pressed against each other. In the portion where the two face each other, strong pressure is applied locally, so that the pressurized conductive member becomes electrically conductive. This results in
Each electrode pad is electrically connected to each electrode bump via a pressurized conductive member, and in turn, through-holes on the test plate,
It is electrically connected to the tester via probe pads, probe pin means, and the like. At this time, the pressing force applied to the test plate from the test object side is partially absorbed by the compressive deformation of the pressurized conductive member, but most of it is evenly received by the probe pin means via the test plate. . As a result, each electrode chip and each electrode bump, and each probe pad and each probe pin means are brought into pressure contact with each other with equal (averaged) pressing force while the test plate remains parallel, resulting in good electrical performance. A connection is established.

As described above, in the present invention, the electrode provided on one surface of the test plate, rather than the probe needle, is pressed against the electrode pad of the object to be tested via the pressurized conductive member. A large number of probe pin means resiliently receive the pressing force from the side of the object to be inspected behind the inspection plate.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic side view showing the overall configuration of the probe device according to this embodiment, FIGS. 2 and 3 are partial sectional views showing the configuration of the main parts of this probe device, and FIG. 4 is a probe pad and print on the top surface of the test plate. FIG. 5 is a plan view showing an example of a wiring pattern, FIG. 5 is a graph showing the pressurized conductive characteristics of the pressurized conductive member, and FIG. 6 is a schematic side view showing the configuration of a modified example.

In FIG. 1, the probe device of this embodiment includes a printed circuit board 10, probe pins 12, and guide pins 1.
6. Consists of an inspection plate mounting block 18, an inspection plate 20, and an inspection plate holding member 30. 40 is a semiconductor wafer, and 44 is a chuck top.

A large number of probe pins 12 are discretely installed on the printed circuit board 10. These probe pins 12 may be commercially available probe pins, but they are much larger and sturdier than the ultrafine probe needles for contacting the electrode pads. Each probe pin 12 is connected to a printed wiring on a printed circuit board 10 via a wire 14, and is further connected to an input/output terminal of a tester (not shown).

A plurality of test plate mounting blocks 18 each having a downward vertical guide pin 16 are fixed to the lower end of the printed circuit board 10.
The inspection plate 2 is inserted through the guide hole 22 of the inspection plate 20.
0 is mounted horizontally to the block 18 and the printed circuit board 10. The holding member 30 attached to the inspection plate mounting block 18 supports the inspection plate 20 by engaging with the step portions at both ends of the inspection plate 20.

As clearly shown in FIG. 2, a probe pad 22 is provided on the top surface of the test plate 20 at a position facing the probe pin 12.
Each probe pad 22 has a probe pin 1 facing it.
2 and pushes up the probe pin 12 somewhat. As a result, when the test plate 20 is attached, each probe pin 12 is pressed against the corresponding probe pad 22 with an appropriate pressing force.

A semiconductor wafer 40 is placed on the bottom surface of the inspection plate 20.
An electrode bump 2 is placed at a predetermined position corresponding to the upper electrode pad 42.
4 are arranged. Each electrode bump 24 is connected to the inspection plate 20
It is electrically connected to the corresponding probe pad 22 via a through hole 26 provided therein and a printed wiring 28 provided on the upper surface of the test board 20 . A plate-shaped pressurized conductive rubber 32 is attached to the lower surface of the test plate 20 so as to cover these electrode bumps 24 .

The pressurized conductive rubber 32 includes, for example, a silicone rubber 32A and a metal particle filler 32B, and when pressurized from the outside, the metal particle filler 32B comes into pressure contact with the applied direction. The pressurized portion has the property (function) of being electrically conductive. That is, Figure 5
As shown in the figure, in the pressurized conductive rubber 30, when the pressurizing force reaches a certain level (strain rate 5%), the resistance value decreases rapidly, and in the strain range beyond that, the conductivity approaches that of metal. can get. In FIG. 5, t is the thickness of the pressurized conductive rubber 30,
Δt represents strain, and R represents resistance value.

As shown in FIG. 4, in this probe device, four sets of electrode patterns are provided on the test plate 20 in order to test, for example, four semiconductor chips at once. In each electrode pattern, the through holes 26 (and the electrode bumps 24 directly below them) are arranged at high density at a small pitch corresponding to the electrode pads 42, but the probe bumps 22 are arranged at a relatively large pitch around the through holes 26. . Therefore, the probe pins 12 that come into contact with the probe bumps 22 in a one-to-one correspondence are also implanted on the printed circuit board 10 in a pattern as shown in FIG.

Next, the operation of this probe device will be explained. First, as shown in FIGS. 1 and 2, the chuck top 44 is sent by an XY stage (not shown) to a position directly below the probe device fixedly arranged at a predetermined position, and the chuck top 44 is moved to a position directly below the probe device fixedly arranged at a predetermined position. Each electrode pad 42 of the chip corresponds to an electrode bump 2 on the lower surface of the test plate 20.
Positioning is performed so that they face each other. At this point, as clearly shown in FIG. 2, each probe pin 12 receives a reference pressure from the inspection plate 20 side, and each
2A is retreated by a predetermined stroke H0 against the compression coil spring 12B.

After alignment, the chuck top 44 and the semiconductor wafer 42 are shown in FIG.
, 40', the semiconductor wafer 40 is pressed against the inspection plate 20. Then, as shown in FIG. 2, the upper surface of the semiconductor wafer 40 comes into pressure contact with the pressurized conductive rubber 32, and the electrode pads 42 of the chip to be inspected are pressed against each other.
In the portion where the metal particle filler 32B and the electrode bump 24 on the lower surface of the test plate 20 face each other, strong local pressure is applied, so that the metal particle filler 32B becomes electrically conductive. As a result, the electrode pad 42 is electrically connected to the electrode bump 24 via the pressurized conductive rubber 32, and as a result, the through hole 26 of the test plate 20, the printed wiring 28, the probe pad 22, and the probe It is electrically connected to a tester via pins 12 and a printed circuit board 10.

When the electrical connection between the present probe device and the chip to be tested on the semiconductor wafer 40 is established as described above, the pressing force applied from the semiconductor wafer 42 side to the test plate 20 is equal to Although some of it is absorbed by the compressive deformation of the conductive rubber 32, most of it is received by the probe pin 12 via the inspection plate 20. As a result, as shown in FIG. 3, the pin 12A of each probe pin 12 further moves upward by ΔH against the compression coil spring 12B.
Retract to stroke H1 (H0 +ΔH). In this way, the contact force between the test plate 20 and the object to be inspected is averaged and received by the large number of probe pins 12 arranged discretely on the upper surface of the test plate 20, so that the test plate 20 is parallel to the test plate 20. While maintaining this state, each electrode chip 42 and each electrode bump 24, and each probe pad 22 and each probe pin 12 are brought into pressure contact with each other with equal pressure. Thereby, a good electrical connection is reliably formed between the present probe device and the chip to be tested on the semiconductor wafer 40. Therefore, highly reliable electrical property testing can be performed.

Furthermore, in this probe device, the electrode bumps 24 on the lower surface of the test plate 20 are in pressure contact with the electrode pads 42 of the chip to be tested via the pressurized conductive rubber 32;
There is no problem such as backlash or breakage of the probe needle as with conventional methods.
Therefore, there is little need for repair or replacement. Furthermore, in the production of the device, there is no assembly work that requires arranging ultrafine probe needles for direct contact with electrode pads at a high density and at a precise pitch, unlike in the past, so production costs can be kept low.

In this embodiment, a raised electrode bump 24 is provided as an electrode on the lower surface of the test plate 20, but even if it is not raised in this way, local conduction may occur between it and the electrode pad 42. It is possible to obtain the status.

FIG. 6 shows the probe device described above.
A spring member 46 is provided in parallel with the probe pin 12 in order to increase the elastic force against the pressing force from the semiconductor wafer side. Alternatively, as another method, for example, probe pins 12 are provided in a matrix at regular intervals,
The arrangement position of the probe bumps 22 on the upper surface of the test plate 20 may be selected according to the electrode pattern to be tested, and in that case, only some of the probe pins 12 will also serve as an electrical contact function.

[0024]

As described above, according to the probe device of the present invention, the electrode provided on one plate surface of the test plate, rather than the probe needle, is connected to the electrode pad of the object to be tested using the pressurized conductive member. Because it is pressure-welded through a 2-way connector, there is little risk of damage or failure, greatly reducing repair and replacement work, and manufacturing is simple and low-cost. Since a large number of probe pin means resiliently receive the pressing force from the test object side behind the test plate, a good electrical connection can be obtained and a highly reliable test can be performed.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing the overall configuration of a probe device according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing the state of essential parts of the probe device of the embodiment before inspection.

FIG. 3 is a partial cross-sectional view showing the state of main parts of the probe device of the embodiment at the time of inspection.

FIG. 4 is a plan view showing an example of a pattern of probe pads and printed wiring on a test board in the probe device of the embodiment.

FIG. 5 is a graph showing the pressure conductivity characteristics of the pressure conductive member used in the probe device of the example.

FIG. 6 is a schematic side view showing the configuration of a modification of the embodiment.

[Explanation of symbols]

10 Printed circuit board 12 Probe pin 18 Inspection plate mounting block 20 Inspection board 22 Probe pad 24 Electrode bump 26 Through hole 28 Printed wiring 32 Pressure conductive rubber 40 Semiconductor wafer 42 Electrode pad 46 Spring member

Claims (1)

[Claims] 1. One plate surface with electrodes arranged at predetermined positions corresponding to a plurality of electrode pads of the object to be inspected, and one-to-one connection via through holes to each electrode on the one plate surface.
a test plate having a second plate surface on which a plurality of probe pads electrically connected are discretely arranged; and a pressurized conductive member provided on one plate surface of the test plate. . A probe device comprising: a plurality of probe pin means for resiliently pressing each probe pad on the other plate surface of the inspection plate with a substantially uniform pressing force.