JPS612339A - Probe card - Google Patents

Abstract

PURPOSE:To prevent the probing precision from deteriorating by a method wherein a power supply channel electrically connected to a probe is composed of a conductive part with large cross-section additionally provided with a condenser. CONSTITUTION:A round hole 2 is opened at almost central part of a substrate 1 while a conductive sheet 3 as a conductive part forming a channel for power supply is provided on the surface. A condenser 4 is formed on the central part of conductive sheet 3 while a probe 5 for power supply is mechanically and electrically connected to the end. A wiring for power supply on the peripheral surface of substrate 1 is electrically connected to respective conductive sheet 3. A signal wiring 8 is formed on the backside of substrate 1 while a signal probe 9 is mechanically and electrically connected to the part around the hole 2. Through these procedures, the impedance in power supply circuit may be reduced to prevent oscillation, etc. while assuring precise probing operation.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a probe card, particularly one equipped with a large number of probe needles, and relates to one that is effective for use in probe testing of wafers in the manufacture of semiconductor devices, for example. .

[Background technology]

2. Description of the Related Art In the manufacture of semiconductor devices, a probe card used for probe testing of wafers may be one in which a power supply path and a signal path are printed on a substrate.

However, the main problem with such a probe card is that when it is equipped with a large number of probe needles, oscillations occur due to the impedance component of the power supply wiring, resulting in a decrease in measurement accuracy. Revealed by the inventor. The conventional probe card technology is described in detail in "Electronic Materials" published by Kogyo Kenkyukai (November 5, 1970, pages 142 to 146).

[Purpose of the invention]

An object of the present invention is to provide a probe card that can prevent a decrease in measurement accuracy even when a large number of probe needles are provided.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Summary of the invention]

A brief overview of typical inventions disclosed in this application is as follows.

That is, the power supply path is formed of a conductive portion having a large cross-sectional area, and a capacitor is added to this conductive portion, thereby reducing the impedance in the power supply path.

[Embodiment 1] FIG. 1 is a top view showing a probe card according to an embodiment of the present invention, and FIG. 2 is an enlarged partial longitudinal sectional view thereof.

In this embodiment, the probe card includes a substrate 1 formed of an insulating material into a substantially square plate shape, and a circular window hole 2 is provided in the substantially central portion of the substrate 1. On the upper surface of the substrate 1, a plurality of conductive plates 3 as conductive parts forming a power supply path are arranged radially around the window hole 2 in close proximity to each other, and each conductive plate 3 is placed on the center side of the lower side. It is formed into a horizontally long, substantially rectangular thin plate having substantially trapezoidal protrusions in its portions. A capacitor portion 4 is formed in the central portion of the conductive plate 3, and a power probe needle 5 is arranged substantially vertically on the end face of the capacitor portion 4 and is mechanically and electrically connected to the capacitor portion 4.

A large number of conductive whiskers 6 are planted on both sides of the conductive plate 3, and the whiskers 6 on adjacent conductive plates 3 are arranged so as to be in electrical contact with each other. A plurality of power supply wires 7 are printed in radial stripes on the peripheral portion of the upper surface of the substrate 1, and the power supply wires 7 are electrically connected to each conductive plate 3, respectively.

A large number of signal wires 8 are printed radially from the window hole 2 to the outer edge on the bottom surface of the substrate 1, and signal probe needles 9 are arranged at an appropriate inclination around the window hole 2 of each signal wire 8. are mechanically and electrically connected.

Next, the effect will be explained.

When the probe card according to the above configuration is used for a wafer probe test, it is attached to a wafer prober (not shown), and the power probe needles 5 and signal probe needles 9 are placed on the electrodes of the wafer (not shown). They are electrically connected to each other. The wafer prober uses these probe needles 5 and 9.
The electrical characteristics of integrated circuits and the like formed on the wafer are measured through the wafer.

When supplying driving power to the wafer through a power supply path, if the power supply path is made up of long and thin printed wiring, oscillations will occur due to its impedance, so signal probe needles are used.

Communication of test signals between the wafer prober and the wafer through the wafer may become unstable, making accurate measurement impossible.

However, in the probe card according to the above configuration,
The power supply path is constituted by a conductive plate 3 having a relatively large cross-sectional area, and the impedance is reduced by adding a capacitor, so that oscillations and the like are prevented from occurring. Therefore, communication of test signals between the wafer prober and the wafer through the signal probe +&19 is performed without being affected by oscillation, etc., ensuring accurate measurement and improving measurement accuracy. .

[Embodiment 2] FIG. 3 is a perspective view showing another embodiment of the present invention, and FIG. 4 is an enlarged partial longitudinal sectional view thereof.

This embodiment is different from the previous embodiments in that the substrate 10 is made of an insulating material and has a laminated structure having a plurality of insulating layers 11, and a plurality of conductive layers 12 as conductive parts for forming power supply paths. , the insulating layers 11 inside the substrate 11 are insulated from each other to form a layered structure, and a capacitor section 13 is added between adjacent conductive layers 12. Since the conductive layer 12 is formed inside the substrate 10, the power wiring to each conductive layer 12 is insulated from each other by the through-hole wiring portion 14 formed in the through-hole of the substrate 10. Further, each power supply probe needle 15 is mechanically and electrically connected to the upper surface of each through-hole wiring section 14 arranged in an annular manner around the window hole 2 of the substrate 10, respectively.

According to this embodiment, since the power supply wiring is constituted by the conductive layer 12 having a large cross-sectional area, the impedance is reduced and the occurrence of oscillation etc. is suppressed. It is possible to carry out communication with the oscillator without being affected by oscillation, and measurement accuracy can be improved.

〔effect〕

(11 By configuring the power supply path with a conductive part with a relatively large cross-sectional area and adding a capacitor, it is possible to reduce the impedance and prevent the occurrence of oscillations, etc., so the signal probe needle Communication of test signals between the wafer prober and the wafer through the wafer prober is performed without being affected by oscillation or the like, making it possible to perform accurate measurements and improve measurement accuracy.

(2) By configuring the power supply conductive part using a conductive plate, it can be configured relatively easily.

(3) By configuring the power supply conductive part from a conductive layer laminated substantially parallel to the inside of the substrate, an increase in the thickness of the substrate can be suppressed.

Although the invention made by the present inventor has been specifically explained based on Examples above, the present invention is not limited to the Examples (although it is possible to make various changes without departing from the gist of the invention). Not even.

For example, the conductive layer is not limited to being disposed parallel to the substrate, but may be disposed substantially perpendicular to the substrate.

[Application field]

In the above explanation, the invention made by the present inventor was mainly applied to a probe card used for wafer probe testing, which is the field of application that formed the background of the invention, but it is not limited to this, and other applications may be considered. It can also be applied to probe cards used for probe tests of electronic components and devices.

[Brief explanation of drawings]

FIG. 1 is a top view showing a probe card which is an embodiment of the present invention, FIG. 2 is an enlarged vertical cross-sectional view of the probe card, FIG. 3 is a perspective view showing another embodiment of the present invention, and FIG. is an enlarged partial vertical sectional view thereof. DESCRIPTION OF SYMBOLS 1... Board, 2... Window hole, 3... Conductive plate (conductive part), 4... Capacitor part, 5... Power supply probe needle, 6... Mustache, 7... Power supply wiring, 8... Signal wiring, 9... Signal probe needle, 10... Board, 11
... Insulating layer, 12... Conductive N (conductive part), 13...
・Capacitor, 14...Through hole wiring section, 15・
...Power source Figure 1 Figure 2 Figure 4

Claims (1)

[Claims] 1. A probe card comprising a power path and a signal path electrically connected to probe needles attached to a substrate, wherein the power path has a large cross-sectional area. 1. A probe card comprising a conductive part having a capacitor added to the conductive part. 2. The probe card as set forth in claim 1, wherein the conductive portion is constituted by a conductive plate disposed substantially perpendicularly to the substrate. 3. The probe card according to claim 1, wherein the conductive portion is constituted by conductive layers stacked inside the substrate substantially parallel and insulated from each other.