JPH0390865A - Probe of probe card - Google Patents

Abstract

PURPOSE:To evaluate electromagnetic characteristics of a semiconductor wafer with more microorder by providing a metallic wire that the tip of an electrode pad is made to contact and an insulator for reinforcement which reinforces the metallic wire. CONSTITUTION:This probe is provided with the metallic wire 6 whose tip is made contact with the electrode pad 5 of the semiconductor wafer and the insulator 7 for reinforcement which is provided surrounding the periphery of the metallic wire 6 and reinforces the metallic wire 6. The metallic wire 6 is reinforced by being surrounded with the reinforcing material 7 made of the electric insulator. Consequently, the metallic wire 6 is usable from a 2.5 mumphi wire diameter when its material is W. Therefore, when the in-plane distribution of the electric characteristics of the semiconductor wafer 2 is measured, fine probing becomes possible because the wire diameter of the metallic wire 6 is small. Consequently, the electric characteristics of the semiconductor wafer can be evaluated with more microorder.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention generally relates to a probe for a probe card used to measure the electrical characteristics of semiconductor wafers, and in particular, to probes for probe cards used to measure the electrical characteristics of semiconductor wafers. The present invention relates to a probe of a probe card that has been improved so that it can be used for evaluation.

[Prior Art] A semiconductor parametric test system is a device that measures basic characteristics of voltage, current, and capacitance necessary for semiconductor device development and process evaluation using a wafer-shaped sample. The measuring device is a combination of a blow μ, a measuring instrument, and a computer (see Yokogawa, Hewlett-Packard Co., Ltd. model 4062B catalog).

A probe card as shown in FIG. 6 (excerpted from Tokyo Electron Ltd.'s probe card brochure) is installed in the blow μ. The probe card consists of a board, a blade, and a probe. The probe is fixed to the board by solder.

FIG. 7 is a diagram showing the shape of a conventional probe (excerpted from Tokyo Electron Ltd., Probe Card Pants 1 Note). In the standard probe, the tip of the probe 1 is bent at a bending angle of 97 to 103 degrees. The diameter φd of the tip of the probe 1 is 60±5 μm. The length class of the main body portion of the probe 1 is 5.5±], mm. The length h of the tip of the probe 1 is 140 to 180 μm.

Next, a method for determining the surface profile distribution of the electrical characteristics of a semiconductor wafer using this probe 1 will be described.

FIG. 8 is a cross-sectional view showing how the in-plane distribution of electrical properties of a semiconductor wafer is being measured.

In the figure, 2 is a semiconductor wafer. An electrode 4 is provided on the back surface of the semiconductor wafer 2, and an electrode pad 5 is provided on the front surface of the semiconductor wafer 2.

The semiconductor wafer 2 is placed on the wafer stage 3 so that the electrode 4 is in contact with the wafer stage 3. When the probe 1 is brought into contact with the electrode pad 5 and a voltage is applied between the probe 1 and the wafer stage 3, a current flows from the back surface to the front surface of the semiconductor wafer 2'. When this current is measured over the entire surface of the semiconductor wafer 2, the in-plane resistance distribution of the semiconductor wafer 2 is determined Δtj.

[Problems to be Solved by the Invention] Now, referring to FIG. 8, if the diameter of the electrode pad 5 is made smaller and the electrodes are attached at a finer pitch, the resistance can be measured at a finer pitch.

However, in the conventional clamping technique, the probe is W, Be
It is made of a material such as Cu or Pd, and considering the strength required during blowing, the diameter of the probe tip could not be made smaller than 30 μm. Therefore, the diameter of the electrode pad 5 was required to be 40 μm or more, and the minimum pitch during blowing was required to be approximately 45 μm or more. If we attempt to minutely measure the resistance of the semiconductor wafer 2 by making the electrode pad 5 smaller and the electrode pitch smaller, the probe 1 will come into contact with the adjacent electrode pad 5, as shown in FIG. However, there was a problem in that it was not possible to accurately evaluate electrical characteristics.

This invention was made in order to solve the above-mentioned problems, and it is an object of the present invention to provide a probe for a probe card that is improved to enable more microscopic evaluation of electrical characteristics of semiconductor wafers. .

[Means for Solving the Problems] The present invention relates to a probe of a probe card used for measuring electrical characteristics and the like of a semiconductor wafer.

In order to solve the above problem, a metal wire whose tip is brought into contact with the electrode pad of the semiconductor wafer, and a reinforcing insulator provided to surround the metal wire and reinforce the metal wire are provided. , is obtained.

According to the probe of the probe card according to the present invention,
Since a reinforcing insulator is provided to reinforce the metal wire, it is possible to reduce the diameter of the metal wire while maintaining a certain probe strength. Therefore, a probe capable of measuring a minute area is realized.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a probe according to an embodiment of the present invention. In the figure, 6 is a metal wire. The metal wire 6 is surrounded and reinforced by a reinforcing material 7 made of an electrical insulator. Therefore, when the material of the metal wire 6 is W, 2
．． It can be used with a wire diameter of 5 μmφ.

Therefore, when measuring the in-plane distribution of electrical properties of a semiconductor wafer, referring to FIG.
Fine blobbing becomes possible.

FIG. 3 is a sectional view of a probe according to another embodiment of the invention. The embodiment shown in FIG. 3 is similar to the embodiment shown in FIG. 1 except for the following points, and corresponding parts are designated by reference numerals, and their explanation will be omitted. The probe shown in Figure 3 differs from the probe shown in Figure 1 in the following points:
The point is that a taper is provided at the tip of the reinforcing member 7, the diameter of which decreases toward the tip. With this configuration, when the probe 1 and the electrode pad 5 come into contact, the reinforcing material 7 is no longer in the way, and a more complete contact state between the metal wire 6 and the electrode pad 5 can be realized.

FIG. 4 is a sectional view of a probe according to still another embodiment of the invention. The embodiment shown in FIG. 4 is similar to the embodiment shown in FIG. 3 except for the following points, and corresponding parts are given the same reference numerals and their explanation will be omitted.

The probe shown in FIG. 4 differs from the probe shown in FIG. 3 in that a wear-preventing cap 8 made of a hard electrically conductive material such as W is provided at the tip of the metal wire. The wear prevention cap 8 is bonded to the tip of the metal wire 6 with solder or the like, which is a good electrical conductor. With such a value of 4Ra, it becomes possible to use materials such as gold, silver, and copper for the metal wire 6, which have low resistance but have been difficult to use in the past due to strength and wear.

FIG. 5 is a sectional view of a probe according to still another embodiment of the invention. This embodiment incorporates a plurality of metal lines that match the pad pattern of the semiconductor device. For example, for a transistor including a source 9, a gate 10, and a drain 11, a probe including three metal lines 6 as shown in the figure is prepared. When such a probe is used, the electrode pad distance can be shortened, and as a result, the in-plane distribution of transistor characteristics can be measured more minutely.

The present invention can be summarized as follows.

(1) A probe of a probe card according to the claims, characterized in that the tip of the reinforcing insulator is processed into a tapered shape.

(2. A probe card according to the claims, further comprising a wear prevention cap 11-8 provided at the tip of the metal wire to prevent wear of the tip of the metal wire. probe.

(3) A probe according to the claims, characterized in that it includes a plurality of metal lines, and the plurality of metal lines are arranged to match the pattern of electrode pads on a semiconductor wafer. card probe.

[Effects of the Invention] As explained above, the probe of the probe card according to the present invention includes a metal wire whose tip is brought into contact with an electrode pad of a semiconductor wafer, and a metal wire provided to surround the metal wire. , and a reinforcing insulator for reinforcing the metal wire, while maintaining a certain probe strength.
It becomes possible to reduce the wire diameter of the metal wire. therefore,
Compared to conventional probes, it is possible to perform more microscopic measurements, and has the effect of enabling more microscopic evaluation of electrical characteristics of semiconductor wafers, for example.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a probe of a probe card according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing how the electrical characteristics of a semiconductor wafer are being measured using the probe shown in FIG. FIG. 3 shows the electrical characteristics of a semiconductor wafer on page 11 using a probe of a probe card according to another embodiment of the present invention.
FIG. FIG. 4 is a diagram showing how the electrical characteristics and the like of a semiconductor wafer are determined using the probes of the probe card according to still another embodiment of the present invention. FIG. 5 is a sectional view showing how dp1, such as the electrical characteristics of a transistor, is determined using a probe of a probe card according to still another embodiment of the present invention. FIG. 6 is a schematic diagram of a conventional probe card. FIG. 7 is a sectional view of a probe of a conventional probe card. FIG. 8 is a cross-sectional view showing how a conventional probe is used to measure the electrical characteristics of a semiconductor wafer. FIG. 9 is a sectional view showing problems when using a conventional probe. In the figure, 1 is a probe, 2 is a semiconductor wafer, 5 is an electrode pad, 6 is a metal wire, and 7 is a reinforcing material. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] A probe of a probe card used for measuring the electrical characteristics, etc. of a semiconductor wafer, comprising: a metal wire whose tip is brought into contact with an electrode pad of the semiconductor wafer; and a metal wire surrounding the metal wire. A probe of a probe card, comprising: a reinforcing insulator for reinforcing the metal wire;