JPH09196970A - Probe card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve propagation characteristics of high frequency of a probe part. SOLUTION: The probe card consists of multiple probes 3, a ring-like printed wiring 2 and a ring-like holding stage 4, etc. The surface on the side of holding the probe of the holding stage 4 is a taper surface 4a crossing the printed wiring board 2, and it is formed so that an outside periphery 4a1 of the taper surface is almost in contact with the rear surface of the printed wiring board 2. On the taper surface 4a, with the probe 3 as an internal conductor, earth boards 12 and 14 are formed with a dielectric layer 13 in between on and under the internal conductor, thus, a probe part has a strip line structure. Alternately, a micro strip line structure omitting either one of the earth boards 12 and 14 may be employed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe card, and more particularly to improvement of transmission characteristics of a probe section.

[0002]

2. Description of the Related Art In IC testers and LCD checkers, a probe card having a plurality of probes is used when inspecting IC chips formed in a matrix on a semiconductor wafer one by one. FIG. 2 is a sectional view of a conventional probe card. In the figure, reference numeral 2 denotes a ring-shaped printed wiring board, which has a wiring pattern 7 connected to each probe 3. Reference numeral 4 denotes a ring-shaped holding table for holding the probe, which is concentrically attached by engaging with the central hole 2a of the printed wiring board 2.

The base portion of the probe 3 is soldered to the back surface of the printed wiring board 2, and the middle portion is the lower surface (tapered surface) 4a of the holding table 4.
, And is fixed with, for example, an epoxy adhesive 5. The printed wiring board 2 is a multi-layer board, and the test signal S is input to the through hole 6a from the tester and sequentially supplied to the probe 3 through the wiring pattern 7 and the through hole 6b inside the board, or from the sample (DUT). The test signal R picked up by the probe passes through the through hole 6b, the wiring pattern 7 and the through hole 6a, and is supplied to the tester.

Although only a pair of left and right probes are shown in FIG. 2, more probes are arranged in a radial direction with the center line L as the center. One wiring pattern 7 for one probe 3
Corresponds to and is extended in the radial direction. Ring-shaped ground patterns 8 and 9 are commonly formed on the front surface and the back surface of the printed wiring board 2 so as to respectively overlap the plurality of wiring patterns 7. The structure in which the ground plate (ground plate) is provided above and below the signal wiring pattern 7 via the dielectric (in this case, the material of the substrate) is called a strip line structure, which is suitable for high frequencies. Has transmission characteristics.

[0005]

The conventional probe card has a drawback that the probe becomes an inductance at a high frequency and the transmission characteristics are deteriorated, so that the high-speed DUT cannot be accurately measured. The present invention aims to solve this drawback and provide a probe card having good transmission characteristics even at high frequencies.

[0006]

[Means for Solving the Problems]

(1) According to the invention of claim 1, a plurality of probes, a ring-shaped printed wiring board having wiring patterns respectively connected to the probes, and a concentric ring which engages with a central hole of the printed wiring board. And a ring-shaped holding table for holding a probe.

According to the present invention, the ring-shaped surface of the holder on the side for holding the probe is a tapered surface that intersects with the printed wiring board, and the outer peripheral edge of the tapered surface is in contact with one surface of the printed wiring board. It is formed. A ground plate is formed on the tapered surface, and a dielectric layer is formed on the ground plate. A probe is arranged in the middle of the dielectric layer, and a second ground plate is formed on the dielectric layer.

(2) According to the inventions of claims 2 and 3, the ground plate 14 or 12 is omitted in the item (1).

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the embodiment shown in FIG. However, in FIG. 1, parts corresponding to those in FIG. In the present invention, the ring-shaped surface of the holding table 4 on the side for holding the probe is the tapered surface 4a intersecting the printed wiring board 2 as in the conventional case, but the outer peripheral edge 4a1 of the tapered surface is the printed wiring board. It is formed so as to be almost in contact with the back surface of 2. (Note that, in the conventional holding table 4 of FIG. 2, there is a step between the outer peripheral edge of the tapered surface 4a and the printed wiring board 2 so as to be separated.) The ring-shaped ground plate 12 is provided on the ring-shaped tapered surface 4a. The dielectric layer 13 is formed concentrically, the dielectric layer 13 is formed on the ground plate 12, and the probe 3 is embedded in the middle of the dielectric layer 13. A ring-shaped second ground plate 14 is formed on the dielectric layer 13 concentrically with the tapered surface 4a.

In this example, the earth plate 12 has an outer peripheral edge of 1
Through the through holes 6C, the ground pattern 8 is connected to the ground pattern 8 at a plurality of locations, while the ground plate 14 is connected to the ground pattern 9 by the ground wire 16. In this way, the ground plates 12, 1 are formed above and below the probe 3 with the dielectric layer 13 interposed therebetween.
By providing 4, the strip line structure using the probe 3 as a conductor is obtained as in the case of the wiring pattern 7 of the printed wiring board in the conventional example, and good transmission characteristics can be obtained even at high frequencies.

FIG. 1B or C shows the case where the ground plate 14 or 12 of FIG. 1A is omitted to reduce the cost. In this case, the structure is a microstrip line structure using the probe as a conductor, and high-frequency transmission characteristics are improved as in FIG. 1A (claims 2 and 3). Ground plate 12 or 14
Can be formed, for example, by plating a metal or applying a conductive paint.

A second dielectric layer is further formed on the second ground plate 14 of FIG. 1A, and a probe is further embedded in the middle of the second dielectric layer to form the second dielectric layer. Form a third ground plate on top, and repeat this laminated structure if necessary,
The probe part can be multi-layered.

[0013]

As described above, according to the present invention, the probe 3
Ground plate 12 or 14 in the vicinity of
By providing, the probe portion has a stripline or microstripline structure. Therefore, good transmission characteristics can be obtained even at high frequencies.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a conventional probe card.

Claims (3)

[Claims] 1. A plurality of probes, a ring-shaped printed wiring board having wiring patterns respectively connected to the probes, and a concentric ring-shaped printed wiring board engaged with a central hole of the printed wiring board. In a probe card comprising a ring-shaped holding table for holding the probe, the ring-shaped surface of the holding table on the side holding the probe is
A tapered surface that intersects with the printed wiring board is formed, and the outer peripheral edge of the tapered surface is formed so as to almost contact one surface of the printed wiring board. A probe card in which a layer is formed, the probe is arranged in the middle of the dielectric layer, and a second ground plate is formed on the dielectric layer. 2. A plurality of probes, a ring-shaped printed wiring board having wiring patterns respectively connected to the probes, and concentrically attached by engaging with a central hole of the printed wiring board, In a probe card comprising a ring-shaped holding table for holding the probe, the ring-shaped surface of the holding table on the side holding the probe is
A tapered surface that intersects with the printed wiring board is formed, and the outer peripheral edge of the tapered surface is formed so as to almost contact one surface of the printed wiring board. A probe card in which a layer is formed, and the probe is held on the dielectric layer. 3. A plurality of probes, a ring-shaped printed wiring board having wiring patterns respectively connected to the probes, and concentrically attached by engaging with a central hole of the printed wiring board, In a probe card comprising a ring-shaped holding table for holding the probe, the ring-shaped surface of the holding table on the side holding the probe is
A tapered surface intersecting with the printed wiring board is formed, and an outer peripheral edge of the tapered surface is formed so as to be substantially in contact with one surface of the printed wiring board. The probe is arranged on the tapered surface, and the probe is arranged. A probe card, wherein a dielectric layer is formed on one surface of the tapered surface, and a ground plate is formed on the dielectric layer.