Test probe

Abstract

Disclosed is a test probe for testing the electrical characteristics of a subject-to-be-tested. The test probe includes a barrel shaped like a cylinder; and a plunger having an inner end portion and a side portion provided inside the barrel. The side portion extends toward an inner end portion with a predetermined curvature in a direction perpendicular to a longitudinal central axis of the barrel.

Description

TEST PROBE

[0001] The disclosure relates to a test probe for testing the electrical characteristics of a semiconductor or the like subject-to-be-tested.

[0002] FIG. 1 illustrates a conventional test probe 1. The conventional test probe 1 includes a cylindrical barrel 10, a plunger 20 partially inserted in a first end portion of the barrel 10, and a spring 30 inserted in the barrel 10.

[0003] The plunger 20 includes a barrel insertion portion 21 accommodated in the barrel 10, and a terminal contact portion 22 exposed to the outside so as to come into contact with a terminal. The terminal contact portion 22 needs to have a very short shape depending on conditions of a subject-to-be-tested.

[0004] FIG. 2 illustrates a state of the conventional test probe 1 during a test. During the test, the terminal contact portion 22 is in contact with and pressed against the terminal of the subject-to-be-tested. In this case, as shown in FIG. 2, the plunger 20 may get stuck in the barrel 10 at first point CP1 on an inner end side of the barrel insertion portion 21, a second point CP2 diagonally facing the first point CP1, and a third point CP3 on the terminal contact portion 22. The plunger 20 is required to operate to compress and restore the spring 30 during the test. However, if the plunger 20 is not restored while being stuck in the barrel 10, there is a problem that the next test is not performed.

[0005] An aspect of the disclosure is to provide a test probe with high test reliability.

[0006] According to an embodiment of the disclosure, there is provided a test probe. The test probe tests the electrical characteristics of a subject-to-be-tested. The test probe includes: a barrel shaped like a cylinder; and a plunger having an inner end portion and a side portion provided inside the barrel. The side portion extends toward an inner end portion with a predetermined curvature in a direction perpendicular to a longitudinal central axis of the barrel.

[0007] The plunger may include a barrel insertion portion comprising the inner end portion and the side portion, and a test contact portion formed integrally with the barrel insertion portion and at least partially protruding toward an outside of the barrel.

[0008] The barrel insertion portion may include a truncated sphere having a first diameter.

[0009] The test contact portion may include a truncated sphere having a second diameter.

[0010] The barrel insertion portion may include a truncated sphere having a first diameter, and the test contact portion may include a truncated sphere having a second diameter smaller than the first diameter.

[0011] The first diameter is smaller than or equal to an inner diameter of the barrel.

[0012] The barrel may include an opening portion having a diameter being reduced along a longitudinal central axis of the barrel, and the second diameter is smaller than or equal to a diameter of the opening portion.

[0013] In the test probe according to an embodiment of the present invention, the inner shape of the plunger inserted into the barrel is formed as a part of a sphere, thereby preventing the plunger from getting caught in the barrel during testing.

[0014] FIG. 1 illustrates a conventional test probe.

[0015] FIG. 2 illustrates an operating state of the conventional test probe shown in FIG. 1.

[0016] FIG. 3 illustrates a test probe according to an embodiment of the disclosure.

[0017] FIG. 4 illustrates an operating state of the test probe shown in FIG. 3.

[0018] Below, various embodiments of the disclosure will be described with reference to the accompanying drawings. FIG. 3 illustrates a test probe 100 according to an embodiment of the disclosure, and FIG. 4 illustrates an operating state of the test probe 100 shown in FIG. 3. Referring to FIG. 3, the test probe 100 includes a cylindrical barrel 110, a plunger 120 partially inserted in a first end portion of the barrel 110, and a spring 130 inserted in the barrel 110.

[0019] The barrel 110 is made of a conductive material, and includes a opening portion 111 narrowed by reducing a diameter at the first end portion to prevent the plunger 120 partially inserted therein from falling out.

[0020] The plunger 120 includes a barrel insertion portion 121 inserted in the barrel 110, and a test contact portion 122 at least partially exposed to the outside of the barrel 110 so as to come into contact with a first terminal (not shown). The barrel insertion portion 121 and the test contact portion 122 are connected to have a concave portion while having spherical surfaces different in curvature from each other.

[0021] The barrel insertion portion 121 includes an inner end portion 121b being in contact with a first side of the spring 130 and a side portion 121a being in contact with the inner surface of the barrel 110 and extending toward an inner end portion with a predetermined curvature in a direction perpendicular to a longitudinal central axis O of the barrel 110.

[0022] The barrel insertion portion 121 may include a portion of a sphere having a diameter of R1. The barrel insertion portion 121 may include a portion of an ellipse sphere.

[0023] The side portion 121a may have a curved surface having a predetermined curvature and extending up to the inner end portion 121b.

[0024] The test contact portion 122 may include a portion of a sphere having a diameter R2.

[0025] The diameter R1 of the side portion 121a may be equal to or smaller than an inner diameter R4 of the barrel 110. Therefore, as shown in FIG. 4, the side portion 121a does not get stuck in the barrel 110 even though it becomes askew while the plunger 120 is operating.

[0026] The test contact portion 122 has a diameter R2 equal to or smaller than a diameter R3 of an opening of the opening portion 111. Therefore, the test contact portion 122 does not get stuck in the opening of the opening portion 111.

[0027] Although not shown in FIGS. 3 and 4, a terminal (not shown) to come into contact with a second terminal (not shown) may be partially inserted in a second end portion of the barrel 110.

[0028] According to an embodiment of the disclosure, the test probe includes the plunger, of which a barrel insertion portion 121 to be inserted in the barrel has a spherical shape, thereby preventing the plunger from getting stuck in the barrel.

[0029] Although exemplary embodiments of the disclosure have been shown and described, the disclosure is not limited to the foregoing specific embodiments, various alternative modifications can be embodied by a person having an ordinary skill in the art without departing from the scope of the disclosure as claimed in the appended claims, and such modified embodiments should not be understood separately from the technical sprit or prospect of the disclosure.

Claims

1.A test probe for testing electrical characteristics of a subject-to-be-tested, the test probe comprising:a barrel shaped like a cylinder; anda plunger having an inner end portion and a side portion provided inside the barrel,wherein the side portion extends toward an inner end portion with a predetermined curvature in a direction perpendicular to a longitudinal central axis of the barrel.2.The test probe of claim 1, wherein the plunger comprises a barrel insertion portion comprising the inner end portion and the side portion, and a test contact portion formed integrally with the barrel insertion portion and at least partially protruding toward an outside of the barrel.3.The test probe of claim 2, wherein the barrel insertion portion comprises a truncated sphere having a first diameter.4.The test probe of claim 2, wherein the test contact portion comprises a truncated sphere having a second diameter.5.The test probe of claim 2, wherein the barrel insertion portion comprises a truncated sphere having a first diameter, and the test contact portion comprises a truncated sphere having a second diameter smaller than the first diameter.6.The test probe of claim 3, wherein the first diameter is smaller than or equal to an inner diameter of the barrel.7.The test probe of claim 4, wherein the barrel comprises an opening portion having a diameter being reduced along a longitudinal central axis of the barrel, andthe second diameter is smaller than or equal to a diameter of the opening portion.

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