Patent Description:
To test electric characteristics of an object to be tested such as a semiconductor, a test device has employed a probe socket for supporting a test probe, and a test circuit board for contacting the test probe and applying a test signal. As a high-frequency and high-speed semiconductor is decreased in pitch and increased in allowable current, a noise shield between signal probes of the probe socket has become very important. That is, the mechanical length, impedance matching, etc. of the test circuit board have become important as test speed and frequency get higher.

A conventional test device includes a probe socket for supporting a signal probe, and a test circuit board placed under the probe socket and providing a test signal. The probe socket performs a test as the signal probe is inserted in a conductive brass block without contact. Further, the test circuit board includes a signal pad and a conductive column formed on an insulating dielectric substrate and transmitting the test signal. When the high-frequency and high-speed semiconductor or the like object that requires high isolation is subjected to the test, a conductive ground body has been used to shield adjacent signal probes of the probe socket from each other. However, for a more reliable test, there is a need of managing an isolation loss caused by noise made between the conductive columns and between the signal pads of the test circuit board. Further, the test circuit board includes a wiring line having a predetermined length, and thus a signal loss is caused corresponding to the length of the wiring line, thereby deteriorating signal transmission characteristics.

<CIT> relates to a method of manufacturing an inspection unit for a high frequency/high-speed device for ensuring reliable connection between the inspection unit and the device to be inspected. <CIT> relates to a high-frequency product inspection apparatus mainly used for characteristic inspection and measurement of electronic parts and circuits that handle high-frequency signals. <CIT> relates to an inspection jig and a contact probe incorporated in the jig, which firmly connect an inspection apparatus to an inspected device in a case where an electric characteristic of this device is inspected before the device is assembled on a circuit board. <CIT> relates to pogo pin-type coaxial and twinaxial connectors. <CIT> relates to a system for high-frequency evaluation of probe measurement networks. <CIT> relates to an inspection socket for inspecting electrical performance before assembling a module of a high frequency / high speed circuit such as an amplifier circuit, a mixer circuit, a filter circuit, a memory, a CPU, and the like to a circuit board.

An aspect of the present disclosure is conceived to solve the conventional problems, and provides a test device which effectively blocks out noise between adjacent signal lines and tests a high-frequency and high-speed semiconductor excellent in transmission characteristics of a test signal.

In accordance with an embodiment of the present disclosure, there is provided a test device according to claim <NUM>. The test device includes: a conductive block which includes a probe hole; at least one signal probe which is supported in an inner wall of the probe hole without contact, includes a first end to be in contact with a testing contact point of the object to be tested, and is retractable in a lengthwise direction; and a coaxial cable which includes a core wire to be in electric contact with a second end of the signal probe. Thus, the test device certainly blocks out noise between the signal probes on a cable supporting substrate and enhances the transmission characteristics of the test signal.

The test device further includes a cable accommodating hole in which the coaxial cable is accommodated, and a cable supporter which includes a cable supporting block coupled to the conductive block so that the probe hole corresponds to the cable accommodating hole, thereby firmly supporting the coaxial cable.

The cable supporting block may include a cable supporting recess for supporting the coaxial cable, thereby preventing the coaxial cable from moving.

The cable supporter further includes an extended plate portion integrally extended from the cable supporting block, thereby preventing interference between the coaxial cables.

The cable supporter includes a cable supporting substrate having a through hole through which the cable supporting block passes, thereby stably fastening the cable supporting block to the conductive block.

With this test device, the coaxial cable is in direct contact with the signal probe, thereby fully blocking out noise in a test circuit board.

The above and/or other aspects will become apparent and more readily appreciated from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings, in which:.

Below, a test device <NUM> according to a first embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

<FIG> is an exploded cross-sectional view of a test socket in the test device <NUM> according to a first embodiment of the present disclosure, and <FIG> are respectively a plane view, a bottom perspective view, an exploded perspective view, a cross-sectional view and a partial enlarged cross-sectional view of the test device <NUM> according to the first embodiment of the present disclosure. As shown therein, the test device <NUM> includes a test socket <NUM>, a coaxial cable <NUM>, and a cable supporter <NUM>.

Referring to <FIG>, the test socket <NUM> includes a conductive block <NUM> having at least one signal probe hole <NUM> and at least one ground probe hole <NUM>; a signal probe <NUM> contactless-accommodated in the signal probe hole <NUM>; a ground probe <NUM> contact-accommodated in the ground probe hole <NUM>; an upper supporting member <NUM> for supporting an upper end of the signal probe <NUM>, and a lower supporting member <NUM> for supporting a lower end of the signal probe <NUM>.

The conductive block <NUM> includes an upper supporting member accommodating groove <NUM> on an upper side to accommodate the upper supporting member <NUM>. The upper supporting member accommodating groove <NUM> includes a shield island <NUM> protruding at the center. The shield island <NUM> blocks out noise made in the signal probes <NUM> supported on the non-conductive upper supporting member <NUM>. The signal probe <NUM> in the middle passes through the signal probe hole <NUM> without contact, and is then supported on the upper supporting member <NUM>.

The signal probe <NUM> has an upper end to be in contact with a testing contact point (not shown) of an object to be tested, and a lower end to be in contact with a core wire <NUM> of the coaxial cable <NUM>. The signal probe <NUM> applies a test signal through the core wire <NUM> of the coaxial cable <NUM>. The signal probe <NUM> may be materialized by a retractable Pogo pin. The signal probe <NUM> includes a barrel (not shown), upper and lower plungers (not shown) partially inserted in the opposite ends of the barrel, and a spring (not shown) arranged between the upper and lower plungers within the barrel. At least one of the upper and lower plungers is inserted in the barrel and slide to compress the spring within the barrel.

The ground probe <NUM> having an upper end to be in contact with a ground terminal of an object to be tested (not shown), and a lower end to be in contact with the cable supporter <NUM>. The ground probe <NUM> receives a ground signal from the object to be tested. The ground probe <NUM> may be may be materialized by a retractable Pogo pin. The ground probe <NUM> includes a barrel (not shown), upper and lower plungers (not shown) partially inserted in the opposite ends of the barrel, and a spring (not shown) arranged between the upper and lower plungers within the barrel. At least one of the upper and lower plungers is inserted in the barrel and slide to compress the spring within the barrel. The ground probe <NUM> is supported being in contact with the conductive block <NUM>.

Referring to <FIG> and <FIG>, the shield island <NUM> is interposed among three signal probe <NUM>, and five ground probe <NUM> are supported being in contact with the shield island <NUM>. In result, the grounded shield island <NUM> shields the signal probes <NUM> from noise.

The upper supporting member <NUM> is fastened to the conductive block <NUM> by a first screw142 as accommodated in the upper supporting member accommodating groove <NUM>, thereby supporting the signal probe <NUM>. The signal probe <NUM> is inserted in the signal probe hole <NUM> of the conductive block <NUM> without contact as floating to prevent a short-circuit. To this end, the insulating upper supporting member <NUM> supports the upper end of the signal probe <NUM>.

Similarly, the lower supporting member <NUM> is made of a conductive material and is accommodated in a lower supporting member accommodating groove <NUM> to support the lower end of the signal probe <NUM>. The signal probe <NUM> is inserted in the signal probe hole <NUM> of the conductive block <NUM> without contact as floating to prevent a short-circuit. The lower supporting member <NUM> includes an insulating signal probe supporting member <NUM> to support the lower end of the signal probe <NUM>. In result, the signal probe <NUM> passes through the conductive block <NUM> and the lower supporting member <NUM> without contact, and the opposite ends of the signal probe <NUM> are supported by the upper supporting member <NUM> and the signal probe supporting member <NUM>.

The signal probe hole <NUM> and the ground probe hole <NUM> are formed penetrating the upper supporting member <NUM>, the conductive block <NUM> and the lower supporting member <NUM>. The signal probe <NUM> is inserted in the signal probe hole <NUM> without contact, and the ground probe <NUM> is inserted in and contacts the ground probe hole <NUM>. In this case, both ends of each of the signal probe <NUM> and the ground probe <NUM> partially protrude from the top and bottom surfaces of the upper supporting member <NUM> and the conductive block <NUM>.

The coaxial cable <NUM> includes a core wire <NUM> placed at the core and transmitting a signal, an external conductor <NUM> surrounding the outer portion of the core wire <NUM> as separated from the core wire <NUM> to block out the noise, and an insulator <NUM> filled in between the core wire <NUM> and the external conductor <NUM>. The core wire <NUM> of the coaxial cable <NUM> is grinded for contact with the signal probe <NUM>. The coaxial cable <NUM> has a first end contacting the signal probe <NUM> and supported on a cable supporting block <NUM> (to be described later), and a second end supported on a cable supporting substrate <NUM> positioned as separated from the first end. The coaxial cable <NUM> includes a signal connector <NUM> to receive a test signal from the outside. The signal connector <NUM> is mounted to the cable supporting substrate <NUM>.

The cable supporter <NUM> includes the cable supporting block <NUM> having a cable accommodating hole <NUM> for accommodating the coaxial cable <NUM>, and the cable supporting substrate <NUM> mounted with the test socket <NUM>.

The cable supporting block <NUM> includes a plurality of cable accommodating holes <NUM> at positions corresponding to the signal probe holes <NUM> of the lower supporting member <NUM>. The cable supporting block <NUM> may be made of conductive metal. The cable supporting block <NUM> is coupled to the conductive block <NUM> by a second screw <NUM> as inserted in a through hole <NUM> of the cable supporting substrate <NUM>. The cable supporting block <NUM> includes a cable supporting recess <NUM> recessed at an opposite side to a portion for contact with the conductive block <NUM>, and an extended plate portion <NUM> extended transversely. The coaxial cable <NUM> is inserted in the cable accommodating hole <NUM> of the cable supporting recess <NUM> and locked with adhesive (or glue) <NUM> filled in the cable supporting recess <NUM>. The extended plate portion <NUM> is in contact with a rear side of the cable supporting substrate <NUM> and supports the cable supporting substrate <NUM> along with the test socket <NUM>.

The cable supporting substrate <NUM> includes one side onto which the test socket <NUM> is mounted, and the rear side to which the second ends of the coaxial cables <NUM> are separately attached for blocking out the noise. The cable supporting substrate <NUM> includes the through hole <NUM> in which the cable supporting block <NUM> is accommodated while penetrating the cable supporting substrate <NUM>.

<FIG> is a cross-sectional view of a test device <NUM> according to an example not forming part of the claimed invention. In comparison with the test device <NUM> described with reference to <FIG>, like numerals refer to like elements, and only different parts will be described.

As shown therein, the test device <NUM> includes the test socket <NUM>, the coaxial cable <NUM>, and the cable supporter <NUM>.

The cable supporter <NUM> does not include the cable supporting substrate <NUM> unlike that of the first embodiment, and the signal connector <NUM> is fastened to the extended plate portion <NUM> instead of the cable supporting substrate <NUM>.

In the test device according to the present disclosure, the signal probe supported in the conductive block is in direct contact with the core wire of the coaxial cable, thereby certainly blocking out the noise between the signal lines at a side of an test circuit board and improving the transmission characteristics of the test signal. Thus, the test device according to the present disclosure enhances the test reliability at a high-speed/high-frequency test.

Claim 1:
A test device for inspecting electric characteristics of an object to be tested, the test device comprising:
a conductive block (<NUM>) which comprises a probe hole;
at least one signal probe configured to pass through the probe hole (<NUM>) without contacting the inner wall of the probe hole, and comprising a first end to be in contact with a testing contact point of the object to be tested, and retractable in a lengthwise direction;
a coaxial cable which comprises a core wire having a first end to be in electric contact with a second end of one of the at least one signal probes; and
a cable supporter (<NUM>), the test device being characterized in that the cable supporter comprises:
a cable supporting block (<NUM>) having a cable accommodating hole (<NUM>) in which the coaxial cable is accommodated and a transverse plate portion (<NUM>), wherein the cable supporting block (<NUM>) is configured to be coupled to the conductive block (<NUM>) so that the position of the probe hole is aligned with the position of the cable accommodating hole; and
a cable supporting substrate (<NUM>) comprising a through hole (<NUM>) through which the cable supporting block passes, wherein the cable supporting substrate includes a first side onto which the conductive block is mounted and a second side opposite to the first side to which a second end of the coaxial cable is attached and wherein the transverse plate portion is in contact with the second side of the cable supporting substrate and supports the cable supporting substrate.