JPH06204303A - Probe device - Google Patents

Abstract

PURPOSE:To conduct an effective electric measurement by the input of high frequency signal by a method wherein a pressing member, with which the surface to be inspected of the material to be inspected when a contact means is brought into contact with the material to be inspected, is provided on a probe card. CONSTITUTION:A driving axle probe 5, which is a contact means, is provided in such a manner that it is cantilever-supported to an insulative probe supporting stand 23 made of ceramic and the like, and extended toward the center of an aperture 31. On the lower surface of a probe card 3, a pair of pressing member 7, which presses from two places on wafer surface, are provided at the position on the rear side of a coaxial probe 51 through the intermediary of a supporting stud 71. This supporting stud 71 is inserted and fixed to the pressing member 7 and fixed there, the base end part of the supporting stud 71 is fixed to the lower surface of the probe card 3, it is brought into contact with the surface to be inspected of the wafer from the bottom face of the pressing member when an inspect ion is conducted, and presses the wafer surface. As a result, the vibration of the material to be inspected is suppressed, and an electric measurement can be conducted accurately.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a probe device.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process,
After the wafer process is completed and an IC chip is completed in the wafer, an electrical measurement called a probe test is performed in order to check the short-circuit and open of the electrode pattern, the input / output characteristics of the IC chip, and the like. The quality of the IC chip is determined in the state of "wafer". After that, the wafer is divided into IC chips, and good ICs
After the chip is packaged, for example, a predetermined probe test is performed to determine the quality of the final product.

Here, in order to perform a probe test in a wafer state, conventionally, for example, above the wafer holder which is movable in the X, Y, Z, and θ directions, it corresponds to the electrode pad arrangement of the IC chips in the wafer. Then, a probe card in which a plurality of probe needles are arranged is arranged, the wafer holder is moved to align the electrode pad of the IC chip in the wafer with the probe needle, and then the probe needle and the electrode pad are brought into contact with each other, and the electrode The pad is electrically connected to the test head through a contact ring including a probe needle and a pogo pin, and electrical measurement is performed to determine the quality of the IC chip.

Here, with the increase in operation speed, some devices used in supercomputers and the like need to apply a high frequency signal having a considerably high frequency for measurement. In order to transmit the signal between the device and the test head, a coaxial probe needle in which an insulator layer and a conductor layer are coaxially provided on the outer circumference of a conductor needle for signal transmission is used. In this case, due to the relationship between the wiring length from the tester and the wavelength of the signal, a reflected wave is generated from the tip of the probe needle, which causes erroneous inspection, but recently, a non-reflection terminator is connected to the tip of the conductor needle. Various measures have been taken such as

By the way, some devices include, for example, a SAW (surface acoustic w) made of crystal.
ave) Some filters, such as a filter, vibrate when a high frequency signal is applied. When such a device is arranged on a wafer, when a high frequency signal is applied during measurement, the IC chip (measurement chip) to be measured is The vibration causes the adjacent IC chip (adjacent chip) to resonate due to this vibration, and the vibration propagates to the measurement chip as a reflected wave, so that the original characteristics cannot be obtained due to the influence of the reflected wave.
Accurate measurement cannot be performed.

Therefore, in order to suppress the resonance of the adjacent chip due to the propagation of the vibration of the measuring chip, a method has heretofore been adopted in which a tape is attached to the boundary region between the measuring chip and the adjacent chip, thereby avoiding the adverse effect of the resonance. .

[0007]

However, the method of sticking the tape along the boundary area on the wafer is very time-consuming and requires a lot of manual work, which is one of the causes of the decrease in throughput. It was also a factor of wafer contamination.

The present invention has been made under these circumstances, and an object thereof is to provide a probe device capable of efficiently performing electrical measurement when inspecting an object to be inspected accompanied by vibration by inputting a high frequency signal. To provide.

[0009]

In the probe device, a contact means provided on a probe card is brought into contact with an object to be inspected, and a high frequency signal is applied to the object to be inspected from the tester side through the contact means. The probe card is provided with a pressing member that presses the surface to be inspected of the object to be inspected when is contacted with the object to be inspected.

[0010]

When the contact means for high frequency signals of the probe card, for example, the coaxial probe needle is brought into contact with the object to be inspected and a high frequency signal is applied to the coaxial probe needle from the tester side, the object to be inspected vibrates. Here, when the contact means comes into contact with the object to be inspected, a surface to be inspected of the object to be inspected, for example, a boundary region between IC chips is pressed, so that a reflected wave from, for example, an adjacent chip due to resonance due to vibration of the measurement chip is suppressed. It is possible,
Therefore, the adverse effect of electrical measurement due to resonance can be avoided.

[0011]

1 to 3 are views showing an embodiment of the present invention. In this embodiment, a wafer holding table 2 which is driven in the X, Y, Z, and θ directions by a driving mechanism 21 in a housing 1.
Is provided, and on the upper side of the wafer holding table 2,
A probe card 3 having an opening 31 in the center is arranged so as to face the wafer holder 2. On the lower surface of the probe card 3, a plurality of probe needles 4 serving as contact means are provided from two opposite sides of the opening 31 corresponding to the arrangement of the electrode pads on the wafer. The support 22 is cantilevered and arranged obliquely downward toward the center. This probe needle 4
Of the contact ring 32 arranged on the probe card 3 is electrically connected to the printed wiring of the probe card 3.
Is electrically connected to the test head 34 via.

Then, on the lower surface of the probe card 3, of the electrode pads arranged on the wafer W, probe needles of the opening 31 corresponding to the position of the electrode pad to be measured by applying or extracting a high frequency signal. Coaxial probe needles 5 serving as contact means are cantilevered one by one from an insulating probe needle support base 23 made of, for example, ceramic, and extend to the center of the opening 31 from the remaining two sides where no 4 is arranged. It is arranged as follows.

The coaxial probe needle 5 uses a coaxial cable 51 in which a conductor layer forming an outer skin is formed on a core wire for signal transmission via an insulating layer, and a conductor needle for signal transmission, which is a core wire, is provided at a tip portion thereof. 52 is exposed and the tip of the exposed portion is directed downward so as to contact with the electrode pad, and the tip of the conductor layer which is the outer cover of the coaxial cable 51 is branched to form the conductor needle 53 for grounding. Is configured. The length of the exposed portion of the conductor needle 52 is preferably 3 mm or less in order to reduce noise, crosstalk, attenuation of high frequency signals and the like.

Two sockets 6A and 6B corresponding to the coaxial cable 51 are provided on both sides of the opening 31 on the surface of the probe card 3 via insulating pedestals 61, respectively. These coaxial cables 51 penetrate the pedestal 61 from the back side of the probe card 3 and are connected to the sockets 6A (6B). However, in FIG. 1, only the socket 6A corresponding to one coaxial cable 51 is shown.

A coaxial cable (not shown) from the test head 34 is connected to the sockets 6A and 6B, and the core wire of the coaxial cable 51 is used for signal input (output) in the test head 34 via the coaxial cable. The conductor layer that is connected to the terminals of the
Grounded within 4.

Further, on the lower surface of the probe card 3, a pair of pressing members 7 for pressing the front surface (surface to be inspected) of the wafer W from two locations are provided, for example, on the rear side of the coaxial probe needle 51 (outer side of the opening 31). ) Is provided via a supporting rod 71.

The pressing member 7 is made of an elastic material, such as rubber, which has a property of absorbing vibration, and is to be measured I
It is formed in a rectangular parallelepiped shape of about 2 mm square and 1 mm thick so as to cover the boundary portion between the C chip and the IC chip adjacent thereto. The support rod 71 has its front end inserted and fixed inside the pressing portion 71, its base end fixed to the lower surface of the probe card 3, and the bottom surface of the pressing member 7 is covered with the wafer W during inspection. It is configured to contact and press the inspection surface.

Next, the operation of the above embodiment will be described. First, a wafer W, which is an object to be inspected, in which IC chips composed of SAW filters configured by using, for example, crystal are vertically and horizontally arranged, is placed on the wafer holding table 2 by a transfer mechanism (not shown) and arranged on the probe card 3. Probe needle 4
Positioning is performed by moving the wafer holder in the X, Y and θ directions by the drive mechanism 21 so that the coaxial probe needle 5 and the electrode pad of the IC chip to be measured correspond to each other.

Then, the wafer holder 2 is raised to a predetermined height and, as shown in FIG. 5, the probe needle 4 and the coaxial probe needle 5 are used as electrode pads of the IC chip (SAW filter) to be measured on the wafer W. As well as contact
The pressing member 7 presses the surface of the boundary area between the IC chip 10a to be measured and the IC chips 10b and 10c adjacent to both sides of the IC chip 10a across both IC chips adjacent to each other.

As a result, the electrode pads of the IC chip 10a are electrically connected to the test head 34 as described above,
The test head 34 measures the direct current characteristics and the like through the probe needle 4, and a high frequency signal is applied through one of the two coaxial probe needles 5 located on both sides of the opening 31 and a high frequency signal is applied through the other. Taken out. In this case, the IC chip 10a is connected to the ground in the test head 34 via the grounding conductor needle 53 of the coaxial probe needle 5, and the ground terminal in the IC chip 10a is grounded.

At the time of measurement, the IC chip 10a to be inspected vibrates due to the application of a high frequency signal.
The IC chip 10a and the IC chip 1 adjacent to the IC chip 10a
Since the boundary area between 0b and 10c is pressed by the pressing member 7, the vibration of the IC chip 10a to be inspected and the propagation of this vibration to the adjacent IC chips 10b and 10c can be suppressed. Resonance of the IC chips 10b and 10c due to the vibration of the IC chip 10a and I
The reflected waves propagating from the C chips 10b and 10c to the IC chip 10a are suppressed.

After the inspection of one SAW filter is completed in this way, the inspection is performed on the next SAW filter arranged on the wafer W by using the same method, and the inspection of all SAW filters is completed. The completed wafer W is unloaded by a transfer mechanism (not shown).

According to such an embodiment, even if the SAW filter on the wafer W vibrates due to the input of the high frequency signal, the vibration reflected by the SAW filter by the pressing member 7 can be suppressed as described above, so that it is accurate. It is possible to perform the measurement and also prevent the probe needle 4 and the coaxial probe needle 5 from coming off from the electrode pad.

In the above, as shown in FIG. 5, the pressing member 7 is composed of the IC chips 10c and 10d adjacent to the IC chip 10a on the left and right sides (directions perpendicular to the case of the previous embodiment) and the IC chip 10a. The boundary regions may be pressed, or the boundary regions at the four corners of the IC chip 10a may be divided and pressed. In the present invention, the area on the surface to be inspected that is pressed by the pressing member 7 can be appropriately set as long as it is a range in which the vibration of the IC chip can be effectively suppressed.

Further, although the pressing member 7 is provided on the probe card 3 via the support rod 71 in the above-mentioned embodiment, it may be provided directly on the probe card 3 or may be provided via a spring. May be. Furthermore, the present invention is not limited to the configuration in which the IC chip is grounded via the conductor layer that is the outer cover of the coaxial probe needle 5.

Further, the contact means for applying the high frequency signal to the IC chip is not limited to the coaxial probe needle 5, but may be a lateral needle or a vertical needle which is not coaxially processed. Note that the present invention can be applied to the case of measuring a device other than the SAW filter as long as a high frequency signal is input to cause vibration.

[0027]

As described above, according to the present invention, the surface to be inspected is pressed by the pressing member provided on the probe card even if the object to be inspected vibrates due to the input of a high frequency signal.
Vibration of the inspection object is suppressed, and as a result, accurate electrical measurement can be performed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of an embodiment of the present invention.

FIG. 2 is a vertical sectional side view showing the overall configuration of the embodiment of the present invention.

FIG. 3 is a vertical sectional side view showing a main part of the embodiment of the present invention.

FIG. 4 is a perspective view showing a state in which the surface of a semiconductor wafer is pressed by a pressing member.

FIG. 5 is a perspective view showing another embodiment of the present invention.

[Explanation of symbols]

 2 Wafer holder 3 Probe card 4 Probe needle 5 Coaxial probe needle 7 Pressing member 71 Support rod 10a to 10e IC chip

Claims (1)

[Claims] 1. A probe device in which a contact means provided on a probe card is brought into contact with an object to be inspected, and a high-frequency signal is applied to the object to be inspected from the tester side through the contact means. A probe device, wherein a pressing member for pressing the surface to be inspected of the object to be inspected when the probe card is contacted with the probe card is provided.