JPH0260229B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a high-speed signal measuring device capable of measuring a semiconductor integrated circuit operating at high speed in a wafer state, and particularly to a high-speed signal measuring device suitable for reducing the impedance of a power supply line.

[Background of the invention]

In high-speed signal measurement equipment that can measure the characteristics of semiconductor integrated circuits (hereinafter abbreviated as IC) in the wafer state, the probe needle of the equipment is shortened to reduce inductance, and the characteristics of the signal transmission path up to the probe needle are shortened. Matching impedance is important for improving frequency characteristics. At the same time, it is necessary to keep the impedance of the power supply line (hereinafter abbreviated as power line) as low as possible. In particular, when measuring the wafer state, the signal ground of the measurement system and the signal ground inside the IC do not necessarily match, so the power supply line often becomes the equivalent signal ground, so it is essential to reduce the impedance of the power supply line.

Japanese Patent Laid-Open No. 59-215737 discloses means for realizing low impedance of a power supply line based on the above viewpoint. This technology has a probe card with a probe needle at the end of a microstrip line that is used for both signal and power lines. By connecting a capacitor provided on the ground plane side of the stripline between the probe needle and the ground plane, the impedance of the power supply line is reduced. This technology is superior in that it can be realized without reducing the density of the probe needles, and it does not require changing the microstrip pattern even if the position of the power supply pad of the IC being measured changes. In order to achieve a low impedance, the shape of the capacitor has to be relatively large, which has the disadvantage that the allowable number of power supply lines is limited by the number of capacitors that can be mounted.

[Purpose of the invention]

An object of the present invention is to provide a high-speed signal measurement device that does not require a reduction in the number of microstrip lines, does not require pattern changes corresponding to the pin arrangement of the IC under test, and can use multiple low-impedance power lines. Our goal is to provide the following.

[Summary of the invention]

In the present invention, on the ground conductor surface of a dielectric substrate that forms a matching transmission path and has a plurality of microstrip lines serving as signal lines and a probe needle provided at the end of the microstrip line,
Further, an insulating layer or an insulator is provided, and at least one conductor wiring for power supply having a width wider than the microstrip line is provided on the insulating layer or insulator, and the conductor wiring for power supply is connected to the probe needle. The present invention is characterized in that a plurality of low impedance power supply lines can be used by providing means for selectively connecting them to those corresponding to the power supply pads of the IC.

[Embodiments of the invention]

An embodiment of the present invention will be described below. An embodiment of the present invention is shown in FIG. 1, and an enlarged sectional view of the vicinity of the probe needle connection portion is shown in FIG. In the figure,
1 is a probe needle, 2 is a ceramic or sapphire substrate or printed circuit board base material on which a microstrip is formed, 4 is a microstrip, 12 is a ground conductor surface of the microstrip, and 13 is a power supply conductor wire. , 3 is the ground conductor surface 12 of the microstrip.
A ceramic or sapphire substrate, a printed circuit board base material, or an insulating resin coating film such as polyimide is used to insulate the power supply conductor 13, the microstrip 4, and the probe needle 1. conductor for connecting with,
5 is a flexible film carrier for supporting 15 and ensuring positioning accuracy;
1 is a resin (adhesive) for fixing the probe needle to the microstrip substrate, and 10 is a support for fixing the substrate 2. FIG. 3 is a perspective view of the structure of the embodiment shown in FIGS. 1 and 2 near the probe needle connection part, and FIG. The connection points are also shown in a somewhat difficult way. FIG. 3b shows the film carrier 5 and the conductor section 15 thereon.
A probe needle that corresponds to the IC power supply pad, and
Microstrip 4 to which the probe needle is connected
connected to.

In the present invention, since the power line 13 is provided on a surface different from the microstrip, the power line 13
It is possible to increase the width of 3 and lower the impedance. Furthermore, since the power supply line 13 faces the ground plane 12 of the microstrip 2 via the thin insulating layer 3, it functions as a capacitor. This eliminates the need for a capacitor for power supply bypass.

Another feature of this embodiment is that since the conductor 15 connecting the power line 13 and the probe needle 1 is provided on the film carrier 5, the conductor pattern 15 can be made sufficiently thick on the side near the power line 13. On the side closer to the microstrip 2, it can be connected to a predetermined probe needle corresponding to the power supply pad of the IC with high positional accuracy.

FIG. 4 shows an example of how to connect the probe needle 1. As shown in the figure, first, the conductor pattern 15 is placed on the film carrier 5 at the same pitch as the microstrip. The probe needle 1 is positioned and fixed, and the probe needle corresponding to a predetermined power supply pin is electrically connected to the conductor pattern 15 on the film carrier. A marker 30 for positioning is attached to the portion of the film carrier 5 to which the probe needle is fixed. Next, the film carrier 5 and the microstrip 2 are aligned and temporarily attached, and each probe needle 1 and the microstrip 2 are electrically connected. Finally, in order to give the probe needle sufficient mechanical strength, the probe needle and the microstrip substrate are hardened with an insulating resin 11.
Be able to complete the structure of the diagram. In this way, by using a film carrier, it is possible to easily and accurately connect the probe needle, the power supply line, and the signal line microstrip.

Note that the microstrip line connected to the power supply line can be used as it is as a voltage sense line. This is an effect in addition to the above-mentioned effects obtained by the present invention.

The support 10 shown in FIG. 1 may be of any type as long as it can fix the microstrip substrate with sufficient strength and positional accuracy.
Further, although the portion that touches the power line 13 needs to be insulated, it is desirable that the other metal portions have a structure that can be commonly grounded.

〔Effect of the invention〕

According to the present invention, even if the position of the power supply pin of the IC changes without reducing the number of usable pins,
It is possible to provide a high-speed signal measuring device that can use a plurality of low impedance power lines without changing the microstripline pattern.

[Brief explanation of the drawing]

FIG. 1 is a bottom view and sectional view showing an embodiment of the present invention, FIG. 2 is an enlarged sectional view of the vicinity of the probe needle connection point, and FIG. 3 is for explaining the shape of the embodiment of FIG. 1. FIG. 4 shows a film carrier for connecting the power supply line and the microstrip, and for easily connecting the probe needle thereto. DESCRIPTION OF SYMBOLS 1... Probe needle, 2... Substrate on which microstrip lines are formed, 3... Insulating layer, 4...
Microstrip line, 12...ground conductor plane, 13...power line conductor, 5...film carrier.

Claims (1)

[Scope of Claims] 1. A plurality of microstrip lines forming matching transmission paths and serving as signal lines are arranged radially, each of the microstrip lines has a probe needle at an end thereof, and An insulating layer or insulating plate is further provided on the ground conductor surface of the dielectric substrate on which the plines are formed, or an insulating plate is provided on the insulating layer or insulating plate, and the width is wider than the microstrip line. A high-speed signal measuring device comprising at least one conductor wiring for power supply, and means for selectively connecting the conductor wiring for power supply to the probe needle. 2. The high-speed signal measuring device according to claim 1, wherein the selective connection means is a conductive pattern formed on a film carrier. 3. The wiring width of the conductor pattern on the film carrier is approximately equal to the conductor width of the microstrip line only in the vicinity where it is connected to the microstrip line, and in other parts, the wiring width of the conductor pattern on the film carrier is approximately equal to the conductor width of the microstrip line. The high-speed signal measuring device according to claim 2, wherein the high-speed signal measuring device is made thick to the same extent as the width. 4. The probe needle is aligned and fixed on the film carrier, electrically connected to the conductive pattern on the film carrier, and aligned and electrically connected to the microstrip line. 3. The high-speed signal measuring device according to claim 2 or 3, wherein the high-speed signal measuring device is fixed. 5. The high-speed signal measuring device according to claim 4, wherein a marker is formed on the film carrier to indicate a fixing point of the probe needle.