Patent Description:
Measurement of electric properties of an inspection object, such as an integrated circuit, as a substrate is performed by using an electric connection device including a probe to be brought into contact with the object. In the configuration of some electric connection devices, a probe head that holds probes is attached to an electrode substrate on which electrode pads electrically connected to the probes are provided.

In the case of attaching the probe head to the electrode substrate, it is necessary to precisely align the probes with the electrode pads for contact. In an example of the method therefor, the probes and electrode pads are aligned by inserting a guide pin provided for the probe head into a guide hole provided for the electrode substrate. <CIT> relates to probe cards and inspection devices and discloses a device according to the preamble of the independent claim. <CIT> discloses a further example of a probe card.

However, the positions of the guide pin and electrode pad are sometimes different from design positions thereof due to manufacturing errors of the probe head and electrode substrate. In such a case, even if the guide pin is inserted into the guide hole, the probe and electrode pad cannot be aligned precisely. This causes an insufficient contact between the probe and electrode pad, leading to problems including imprecise electric measurement of an inspection object.

In the light of the aforementioned problem, an object of the present invention is to provide an electric connection device in which the probe held by the probe head and the electrode pad provided for the electrode substrate are aligned precisely.

According to an aspect of the present invention, provided is an electric connection device according to claim <NUM>.

According to the present invention, it is possible to provide an electric connection device in which the probe held by the probe head and the electrode pad provided for the electrode substrate are aligned precisely.

Next, an embodiment of the present invention is described with reference to the drawings. In the following description of the drawings, the same or similar portions are given the same or similar reference numerals. The drawings are schematic, and it should be noted that thickness proportions and the like are different from real ones. It is also obvious that dimensional relationship or proportions of some portions are different from each other throughout the drawings. The embodiment below illustrates a device and a method to embody the technical idea of the present invention. The embodiment of the present invention does not specify the material, shape, structure, arrangement, and the like of the constituent components to the following ones.

As illustrated in <FIG>, an electric connection device <NUM> according to an embodiment of the present invention includes: a probe head <NUM>, which holds probes <NUM>; and an electrode substrate <NUM>, on which electrode pads <NUM> are provided. <FIG> illustrates the probes <NUM> through the side surface of the probe head <NUM>.

The probe head <NUM> is laid on and attached to the electrode substrate <NUM>, and proximal ends of the probes <NUM> are electrically connected to the respective electrode pads <NUM>. As illustrated in <FIG>, the proximal ends of the probes <NUM> protruding from the upper surface of the probe head <NUM>, that faces the electrode substrate <NUM>, are connected to the respective electrode pads <NUM>, which are provided on the lower surface of the electrode substrate <NUM>, that faces the probe head <NUM>.

The electric connection device <NUM> illustrated in <FIG> is a vertically-moving probe card, and the distal ends of the probes <NUM> exposed from the lower surface of the probe head <NUM> are brought into contact with inspection pads (not illustrated) of an inspection object <NUM> that is placed under the electric connection device <NUM>. In the state illustrated in <FIG>, the probes <NUM> are not in contact with the inspection object <NUM>. When a chuck <NUM> with the inspection object <NUM> placed thereon is elevated, the distal ends of the probes <NUM> come into contact with the inspection object <NUM>, for example.

The electrode pads <NUM> of the electrode substrate <NUM> are electrically connected to the respective connection pads <NUM>, which are provided on the upper surface of the electrode substrate <NUM>, through respective electrode interconnections <NUM>, which are provided within the electrode substrate <NUM>. The connection pads <NUM> are electrically connected to an inspection apparatus, such as an IC tester (not illustrated). The inspection apparatus applies a predetermined voltage or current to the inspection object <NUM> through the probes <NUM>. Signals outputted from the inspection object <NUM> are transmitted to the inspection apparatus through the probes <NUM> for inspection of the properties of the inspection object <NUM>.

The probe head <NUM> is provided with guide pins <NUM> for alignment of the probe head <NUM> and electrode substrate <NUM>. The electrode substrate <NUM> includes a guide hole group composed of plural guide holes corresponding to each guide pin <NUM>. In the electric connection device <NUM>, each guide pin <NUM> corresponds to a guide hole group including a reference guide hole <NUM>, which is located at a design reference position, and spare guide holes <NUM> and <NUM>, which are located in the vicinity of the reference guide hole <NUM>, as illustrated in <FIG> illustrates a state where the guide pin <NUM> is fitted in the reference guide hole <NUM>.

The design reference position at which the reference guide hole <NUM> is to be located is determined based on the position of the guide pin <NUM> determined when the electric connection device <NUM> is designed. Specifically, the design reference position is determined so that the probes <NUM> come into proper contact with the respective electrode pads <NUM> when the probe head <NUM> is attached to the electrode substrate <NUM> as designed with the guide pins <NUM> fitted in the reference guide holes <NUM>. Herein, "the probes <NUM> come into proper contact with the respective electrode pads <NUM>" means that the proximal end of each probe <NUM> is in contact with the center region of the corresponding electrode pad <NUM> and the electric contact resistance between the probe <NUM> and electrode pad <NUM> is low enough to enable precise measurement of the electric properties of the inspection object <NUM>.

However, the positions of the guide pins <NUM> and reference guide holes <NUM> are sometimes different from the design positions thereof due to assembly error, processing error, deflection of materials, and the like caused during fabrication of the probe head <NUM> and electrode substrate <NUM>. The positions of the guide pins <NUM> and reference guide holes <NUM> tend to differ from the design positions thereof, particularly due to an increase in size of the probe head <NUM> or reduction in pitch of the probes <NUM>.

When the probe head <NUM> is attached to the electrode substrate <NUM> with the guide pins <NUM> fitted in the reference guide holes <NUM> but the positions of the guide pins <NUM> and reference guide holes <NUM> differ from the design positions thereof, the probes <NUM> and electrode pads <NUM> are misaligned. Furthermore, the probes <NUM> and electrode pads <NUM> can be sometimes misaligned when the probe head <NUM> is detached from the electrode substrate <NUM> for replacement or repair and is then attached again to the electrode substrate <NUM>. In such cases, bad contact between the probes <NUM> and the electrode pads <NUM> prevents precise electric inspection of the inspection object <NUM>.

In the electric connection device <NUM>, when the guide pins <NUM> are fitted in the respective reference guide holes <NUM> but the probes <NUM> are not in proper contact with the electrode pads <NUM>, each guide pin <NUM> is fitted to any one of the spare guide holes. The spare guide holes to be fitted to the respective guide pins <NUM> are selected so that the probes <NUM> come into proper contact with the respective electrode pads <NUM>.

When the guide pins <NUM> are fitted in the reference guide holes <NUM> but the probes <NUM> are not in proper contact with the respective electrode pads <NUM>, the probes <NUM> and electrode pads <NUM> come into proper contact by fitting each guide pin <NUM> to any one of the spare guide holes. The positions of the spare guide holes are determined so as to resolve misalignment of the probes <NUM> and electrode pads <NUM>. Specifically, the relative positions of each reference guide hole <NUM> and the corresponding spare guide holes are determined considering the expected amounts of displacement of the reference guide hole <NUM> and the corresponding guide pin <NUM> from the design positions thereof.

The positions at which the spare guide holes are to be located are determined based on design error of the electric connection device <NUM> and past data of misalignment of the probes <NUM> and electrode pads <NUM> when the guide pins <NUM> are fitted in the reference guide holes <NUM>, for example. The number of spare guide holes and the positions thereof can be arbitrarily determined in such a range that satisfies the aforementioned conditions.

As illustrated in <FIG>, spare guide holes <NUM> to <NUM> are individually located around the reference guide hole <NUM> (above, below, and to the right and left of the reference guide hole <NUM> on the page), for example. <FIG> is a plan view of the surface of the electrode substrate <NUM> that faces the probe head <NUM>. In <FIG>, the guide pins <NUM> are fitted in the respective reference guide holes <NUM>. <FIG> is a cross-sectional view taken along II-II direction of <FIG>.

Consideration is given a case where the guide pins <NUM> are fitted in the reference guide holes <NUM> as illustrated in <FIG> but the proximal ends of the probes <NUM> and electrode pads <NUM> are not in proper contact as illustrated in <FIG>, for example. As illustrated in <FIG>, the proximal end of each probe <NUM> is displaced to the right from the center of the corresponding electrode pad <NUM> (on the page).

In this case, as illustrated in <FIG>, the guide pins <NUM> are fitted in the spare guide holes <NUM>, that is located to the left of the corresponding reference guide hole <NUM> on the page. This allows the proximal ends of the probes <NUM> to come into contact with the centers of the respective electrode pads <NUM> as illustrated in <FIG>.

In the examples illustrated in <FIG>, the guide hole groups each composed of the reference guide hole <NUM> and the spare guide holes around the same are located at corners on a diagonal of the electrode substrate <NUM> across the center thereof. The regions where the guide hole groups are located are not limited to the aforementioned two places. The guide hole groups may be located at four respective corners, for example. Preparing plural guide hole groups and plural guide pins <NUM> corresponding thereto in such a manner enables more precise alignment of the probe head <NUM> and electrode substrate <NUM>.

As described above, the electric connection device <NUM> according to the embodiment of the present invention is equipped with a guide hole group, that is composed of the reference guide hole <NUM> and spare guide holes provided around the same. The guide holes to be fitted to the guide pins <NUM> can be selected from the spare guide holes in addition to the reference guide holes <NUM> so that the probes <NUM> can come into proper contact with the respective electrode pads <NUM> of the electrode substrate <NUM>. According to the electric connection device <NUM> illustrated in <FIG>, it is possible to easily resolve misalignment of the probes <NUM> and electrode pads <NUM>.

When the guide pins <NUM> are fitted in the guide holes <NUM>, the proximal ends of the probes <NUM> are displaced by about <NUM> to <NUM> from the centers of the respective electrode pads <NUM> with outer diameters of <NUM> to <NUM>, for example. In such a case, spare guide holes are prepared at distances of <NUM> to <NUM> from each reference guide hole <NUM> so that the guide pins <NUM> are fitted in corresponding spare guide holes. This allows the proximal ends of the probes <NUM> to come into contact with the center regions of the respective electrode pads <NUM>.

As measurement is repeated, misalignment of the probes <NUM> and electrode pads <NUM> increases in many cases compared with the state where the probe head <NUM> is attached to the electrode substrate <NUM> for the first time. The contact resistance between the probes <NUM> and electrode pads <NUM> is thereby increased, thus resulting in imprecise measurement of the electric properties of the inspection object <NUM>. In the state where the probe head <NUM> is attached to the electrode substrate <NUM> for the first time in particular, it is preferred that the proximal ends of the probes <NUM> are in contact with the center regions of the respective electrode pads <NUM>. This enables electric measurement of the inspection object <NUM> with high degree of accuracy even after the measurement is repeated.

The guide holes to be fitted to the guide pins <NUM> can be selected by various methods. For example, the guide pins <NUM> are fitted in the reference guide holes <NUM> at first. If the probes <NUM> and electrode pads <NUM> are misaligned, the direction and distance of the misalignment are checked. The spare guide hole to be fitted to each guide pin <NUM> is properly selected based on the conditions of the misalignment.

<FIG> illustrates the configuration where the spare guide holes are individually located above, below, and to the right and left of each reference guide hole <NUM> by way of example. However, the numbers of spare guide holes located above, below, and to the right and left of each reference guide hole are not limited to one and may be more than one. <FIG> illustrates an example in which two spare guide holes are located at each side above, below, and to the right and left of the reference guide hole <NUM>. In <FIG>, reference numerals of the spare guide holes are not illustrated. The spare guide holes may be arranged in a radial fashion or may include one spare guide hole.

Alternatively, as illustrated in <FIG>, the spare guide holes (reference numerals thereof are not illustrated) may be arranged concentrically around the reference guide hole <NUM>. The spare guide holes may be arranged around the reference guide hole <NUM> in multiple layers.

As described above, the positions of the spare guide holes can be arbitrarily determined according to the expected direction of misalignment of the probes <NUM> and electrode pads <NUM>. The spare guide holes may be intensively located only in a particular direction from the reference guide hole <NUM>, for example.

The present invention is described with the embodiment above. However, it should not be understood that the present invention is limited by the description and drawings constituting a part of the disclosure. Based on the disclosure, those skilled in the art will appreciate various substitutions, examples, and operation techniques.

In the aforementioned example, the guide pins <NUM> are provided for the probe head <NUM> while the guide holes are provided for the electrode substrate <NUM>. However, the guide pins <NUM> may be provided for the electrode substrate <NUM> while the guide holes are provided for the probe head <NUM>.

Claim 1:
An electric connection device, comprising:
a probe (<NUM>);
a probe head (<NUM>) that holds the probe (<NUM>); and
an electrode substrate (<NUM>) on which an electrode pad (<NUM>) to be connected to a proximal end of the probe (<NUM>) is provided, wherein
the probe head (<NUM>) is provided with a plurality of guide pins (<NUM>) for alignment of the probe head (<NUM>) and the electrode substrate (<NUM>), and
wherein
the electrode substrate (<NUM>) is provided with a guide hole group composed of a plurality of guide holes corresponding to the plurality of guide pins, and (<NUM>)
the guide hole group being corresponding to each of the guide pins (<NUM>), characterized in that
the guide hole group is composed of a reference guide hole (<NUM>) located at a design reference position and a plurality of the spare guide holes (<NUM>-<NUM>) located around the reference guide hole (<NUM>), wherein the relative positions of the reference guide hole (<NUM>) and the spare guide holes (<NUM>-<NUM>) are determined considering the expected amounts of displacement of the reference guide hole (<NUM>) and the corresponding guide pin (<NUM>) from the design reference position thereof.