Test probe and test device

Abstract

Disclosed is a test probe. The test probe includes: a barrel including a tubular barrel main body, and a plurality of skirt portions formed in a first end portion of the barrel main body and spaced apart from each other by lengthwise slits; and a plunger including a sliding portion accommodated in the barrel main body, and a terminal contact portion extending from the sliding portion and exposed through the skirt portion to come into elastic contact with the skirt portion. The skirt portion includes a skirt main body formed to be decreased in diameter having a partially conical shape along a direction from the barrel main body to a fore-end, and a skirt fore-end portion provided in a fore-end area of the skirt main body. The skirt fore-end portion includes a sectional contact surface formed on an inner diameter surface thereof, with which an outer diameter surface of the terminal contact portion is in contact throughout a predetermined length section.

Description

TEST PROBE AND TEST DEVICE

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

[0002] FIG. 1 is a view showing a conventional test probe 10.

[0003] Referring to FIG. 1, a test probe 10 includes a cylindrical barrel 11, a plunger 12 coupled to and slidable within one side of the barrel 11, a terminal 13 secured to the other side of the barrel 11, and a spring 14 inserted between the plunger 12 and the terminal 13 in the barrel 11 and providing elasticity.

[0004] A test signal may be transmitted from the plunger 12 to the terminal 13 via the barrel 11 and the spring 14. In more detail, the test signal applied to the plunger 12 is transmitted to the terminal 13 secured to a second end portion of the barrel 11 via a first end portion of the barrel 11, the inner wall of the barrel 11 and the spring 14. In this case, the plunger 12 and the barrel 11 is required to maintain an appropriate gap therebetween for the smooth sliding of the plunger 12. Such a gap causes unstable contact during a test, and results in unstable resistance as shown in FIG. 2, thereby leading to a problem of misjudging a good subject-to-be-tested as a defective product.

[0005] An aspect of the disclosure is to provide a test probe and a test device, in which a stable signal transmission path is ensured during a test, thereby increasing the reliability of the test.

[0006] Another aspect of the disclosure is to provide a test probe and a test device, which are excellent in durability.

[0007] According to an embodiment of the disclosure, there is provided a test probe. The test probe includes: a barrel including a tubular barrel main body, and a plurality of skirt portions formed in a first end portion of the barrel main body and spaced apart from each other by lengthwise slits; and a plunger including a sliding portion accommodated in the barrel main body, and a terminal contact portion extending from the sliding portion and exposed through the skirt portion to come into elastic contact with the skirt portion. The skirt portion may include a skirt main body formed to be decreased in diameter having a partially conical shape along a direction from the barrel main body to a fore-end, and a skirt fore-end portion provided in a fore-end area of the skirt main body. The skirt fore-end portion may include a sectional contact surface formed on an inner diameter surface thereof, with which an outer diameter surface of the terminal contact portion is in contact throughout a predetermined length section.

[0008] An area of the sectional contact surface may include a thick portion extending outwards in a radial direction beyond the thickness of the skirt main body.

[0009] The skirt portion may be thicker than the barrel main body.

[0010] The sectional contact surface may be formed by chamfering or cutting,

[0011] A circumferential inner surface curvature of the sectional contact surface may be smaller than a circumferential outer surface curvature of the terminal contact portion.

[0012] According to another embodiment of the disclosure, there is provide a test probe. The test probe includes a barrel including a tubular barrel main body, and a plurality of skirt portions formed in a first end portion of the barrel main body along a lengthwise direction and spaced apart from each other by slits; and a plunger including a sliding portion accommodated in the barrel main body, and a terminal contact portion extending from the sliding portion and exposed through the skirt portion to come into elastic contact with the skirt portion. The skirt portion may include a skirt main body formed to be decreased in diameter having a partially conical shape along a direction from the barrel main body to a fore-end, and a skirt fore-end portion provided in a fore-end area of the skirt main body. The barrel main body may include a protrusion protruding toward an inside of the barrel main body at an edge facing the slit.

[0013] According to an embodiment of the disclosure, a test device includes a test socket supporting the test probe to make both end portions of the test probe partially protrude therefrom.

[0014] A test probe according to an embodiment of the present invention includes a barrel body and a plurality of skirt parts separated by a slit formed in the longitudinal direction at one end of the barrel body and having a reduced diameter toward the central axis. The inner surface of the tip area of each skirt portion has a section contact surface that can elastically contact the outer diameter surface of the plunger over a predetermined length section. The section contact surface can improve the reliability of inspection by maintaining stable contact with the plunger during inspection.

[0015] As the skirt portion is separated by the slit, durability may decrease. Accordingly, durability can be increased by forming at least a portion of the skirt portion to be thicker than the barrel body.

[0016] The tip edge of the inner diameter surface of the skirt portion is made to be non-contact with the outer surface of the plunger, so that the outer surface of the plunger can be prevented from being scratched during inspection.

[0017] At least a portion of the plunger in contact with the section contact surface may be formed so that its diameter decreases in the direction in which it is pressed during inspection. Accordingly, durability of the skirt portion can be improved by not contacting with the plunger or contacting it with minimal pressing force before inspection and by contacting with the plunger during inspection.

[0018] FIG. 1 is a view showing a conventional test probe.

[0019] FIG. 2 is a view showing distribution of resistance measured during a test using a conventional test probe.

[0020] FIG. 3 is a perspective view of a test probe according to a first embodiment of the disclosure.

[0021] FIG. 4 is a cross-sectional view of the test probe taken along line A-A of FIG. 3.

[0022] FIG. 5 is a view showing a contact state between a skirt portion and a terminal contact portion of a plunger in FIG. 3.

[0023] FIG. 6 is a view showing distribution of resistance measured during a test using the test probe according to the first embodiment of the disclosure.

[0024] FIG. 7 is a view showing the test probe according to the first embodiment of the disclosure and a test device with the test probe supported in a test socket.

[0025] FIG. 8 is a view showing a test probe according to a second embodiment of the disclosure.

[0026] FIG. 9 is a view showing a test probe according to a third embodiment of the disclosure.

[0027] FIG. 10 is a view showing a test probe according to a fourth embodiment of the disclosure.

[0028] FIG. 11 is a view showing a test probe according to a fifth embodiment of the disclosure.

[0029] FIG. 12 is a cross-sectional view taken along line B-B of FIG. 11.

[0030] FIG. 13 is a view showing a test probe according to a sixth embodiment of the disclosure.

[0031] FIG. 14 is a view showing an operating state of the test probe of FIG. 13.

[0032] FIG. 15 is a schematic diagram showing a method of manufacturing a barrel of FIG. 3.

[0033] FIG. 16 is a schematic diagram showing a method of manufacturing a barrel of FIG. 9.

[0034] FIG. 17 is a schematic diagram showing a method of manufacturing a barrel of FIG. 10.

[0035] FIG. 18 is a schematic diagram showing a process of assembling the test probe according to the first embodiment of the disclosure.

[0036] Below, a test probe 100 according to embodiments of the disclosure will be described in detail with reference to the accompanying drawings.

[0037] FIG. 3 is a perspective view of a test probe 100 according to a first embodiment of the disclosure, and FIG. 4 is a cross-sectional view of the test probe 100 taken along line A-A of FIG. 3.

[0038] Referring to FIGS. 3 and 4, the test probe 100 includes, for example, a cylindrical barrel 110, a plunger 120 coupled to and slidable within a first side of the barrel 110, a terminal 130 secured to a second side of the barrel 110, and an elastic body 140 inserted between the plunger 120 and the terminal 130 in the barrel 110 and providing elasticity.

[0039] The barrel 110 includes a barrel main body 111, and a skirt portion 112 extending along a lengthwise direction at a first end portion, in which the plunger 120 is inserted, and separated by a plurality of slits 113 formed at predetermined intervals along a circumferential direction. There may be two or more slits 113. The slits 113 may extend diagonally or spirally with respect to the lengthwise direction of the test probe 100. The slit 113 may be formed by cutting to have a uniform width or a tapering shape.

[0040] The plunger 120 may include a sliding portion 121 accommodated and sliding in the barrel main body 111, and a terminal contact portion 122 extending from the sliding portion 121, exposed through the skirt portion 112, and elastically coming into contact with the skirt portion 112.

[0041] The sliding portion 121 has a diameter corresponding to the inner diameter of the barrel main body 111. The diameter of the sliding portion 121 is set to be smaller than the barrel main body 111 so as to slide within the barrel main body 111.

[0042] The terminal contact portion 122 has a diameter smaller than the diameter of the sliding portion 121. The diameter of the terminal contact portion 122 is set to such an extent that the terminal contact portion 122 can pass being in contact with a fore-end of the skirt portion 122. The end portion of the terminal contact portion 122 comes into contact with the terminal 310 (see FIG. 7).

[0043] The terminal 130 fixedly secured to a second end portion of the barrel 110 by dimpling or caulking. Alternatively, the terminal 130 may be not fixedly secured but slidably inserted.

[0044] The elastic body 140 is compressed and restored as the plunger 120 moves sliding during a test. The elastic body 140 may for example be implemented by a coil spring.

[0045] FIG. 5 is a view showing a contact state between the skirt portion 112 and the terminal contact portion 122 of the plunger 120 in FIG. 3, and FIG. 6 is a view showing distribution of resistance measured during a test using the test probe 100 according to the first embodiment of the disclosure.

[0046] Referring to FIG. 5, the skirt portion 112 includes a skirt main body 1121 formed to be decreased in diameter having a partially conical shape along a direction from the barrel main body 111 to the fore-end, and a skirt fore-end portion 1122 provided in a fore-end area of the skirt main body 1121.

[0047] The inner diameter surface of the skirt fore-end portion 1122 has a sectional contact surface CS with which the outer diameter surface of the terminal contact portion 122 can be in contact throughout a predetermined length section L. The inner diameter surface of the skirt fore-end portion 1122 presses the outer surface of the terminal contact portion 122 with a contact force weaker than the restoring force of the elastic body 140. If the contact force is stronger than the restoring force of the elastic body 140, the plunger 120 inserted into the barrel 110 by pressing during the test may not return to its original position.

[0048] As shown in (a) of FIG. 5, the fore-ends of the skirt portions 112 adjacent to each other have a slight clearance G therebetween to prevent interference with each other when elastically moving in a radial direction.

[0049] When the terminal contact portion 122 is not inserted within the barrel 110, the sectional contact surface CS of the skirt portion 112 is positioned within the outer diameter surface of the terminal contact portion 122. Therefore, the sectional contact surface CS of the skirt portion 112 inserted in the terminal contact portion 122 can be always in contact with the outer diameter surface of the terminal contact portion 122.

[0050] The inner diameter surface of the skirt fore-end portion 1122 and a fore-end surface edge 1123 of the skirt fore-end portion 1122 are chamfered to have a predetermined curvature. For example, the circumferential inner surface curvature of the sectional contact surface CS of the skirt fore-end portion 1122 is smaller than the circumferential outer surface curvature of the terminal contact portion 122. Only an inward portion of the inner diameter range of the sectional contact surface CS is in contact with the outer surface of the terminal contact portion 122. In other words, outward edge portions of the inner diameter range of the skirt fore-end portion 1122 may be spaced apart from the outer diameter surface of the terminal contact portion 122.

[0051] Such features of the skirt fore-end portion 1122 provide a minimal contact force while ensuring the contact between the inner diameter surface of the skirt fore-end portion 1122 and the outer diameter surface of the terminal contact portion 122, thereby preventing the plunger 120 inserted during the test from failing to return to its original position. In particular, the outer diameter surface of the terminal contact portion 122 is spaced apart from the edge portions of the inner diameter range of the skirt fore-end portion 1122, thereby solving a problem that the durability is deteriorated as the edge portions of the skirt fore-end portion 1122 scratch the outer diameter surface of the terminal contact portion 122 during the test. Alternatively, the circumferential inner surface curvature of the sectional contact surface CS may be smaller than the circumferential outer surface curvature of the terminal contact portion 122.

[0052] A bending angle between the inner surface of the skirt main body 1121 and the sectional contact surface CS may range from 155 to 175 degrees. The bending angle may be varied depending on the length of the skirt portion 112 and the outer diameter of the terminal contact portion 122.

[0053] Referring to FIG. 6, the test probe 100 according to the disclosure mostly have a constant resistance of about 50Ω during the test. This is because the skirt fore-end portion 1122 of the skirt portion 112 always presses and maintains contact with the outer diameter surface of the terminal contact portion 122 of the plunger 120 during the test.

[0054] FIG. 7 is a view showing the test probe 100 according to the first embodiment of the disclosure and a test device 1 with the test probe 100 supported in a test socket 200.

[0055] Referring to (a) of FIG. 7, the test probe 100 is before being supported in a probe accommodating portion 210 of the test socket 200. A first end portion 121E of the sliding portion 121 is in contact with the inner diameter surface of the skirt portion 112 below a bending portion TP. In other words, the bent skirt portion 112 serves to prevent the sliding portion 121 from falling out of the barrel 110. Meanwhile, the pressing force applied by the skirt portion 112 to the terminal contact portion 122 is reduced by the first end portion 121E of the sliding portion 121.

[0056] Referring to (b) of FIG. 7, the test probe 100 is being supported in the probe accommodating portion 210 of the test socket 200. The first end portion 121E of the sliding portion 121 is positioned inside the barrel main body 111 beyond the bending portion TP. In this case, the skirt portion 112 is released from the contact with the first end portion 121E of the sliding portion 121, and the reduced pressing force of the skirt portion 112 is restored and added to the terminal contact portion 122.

[0057] FIG. 8 is a view showing a test probe 100 according to a second embodiment of the disclosure

[0058] Referring to FIG. 8, the plunger 120 includes the sliding portion 121 inserted in the barrel main body 111, the terminal contact portion 122 to come into contact with a terminal 310 (see FIG. 7) of a test circuit board (see FIG. 7), and an inclined contact portion 123 connecting between the sliding portion 121 and the terminal contact portion 122.

[0059] The inclined contact portion 123 has a conical section gently inclined to be in contact with or proximity to the inner surface of the skirt portion 112.

[0060] In the test probe 100 of the disclosure, the fore-end of the skirt portion 112 is always in contact with the terminal contact portion 122 of the plunger 120, and thus required to have concentric movement along a central axis. Eccentric movement causes a problem of making the weak skirt portion 112 be forcibly deformed, for example, changed in a bending angle. The inclined contact portion 123 having the conical section may be guided by the inner surface of the skirt portion 112 being in contact therewith or proximity thereto, thereby moving concentrically.

[0061] FIG. 9 is a view showing a test probe 100 according to a third embodiment of the disclosure.

[0062] Referring to FIG. 9, the skirt portion 112 has a thick portion 1124 extending outwards in a radial direction in an area of the sectional contact surface CS.

[0063] To be in linear contact with the terminal contact portion 122 along a lengthwise direction, the sectional contact surface CS is formed by machining the fore-end the inner diameter surface of the skirt portion 112 with a predetermined angle, for example, as shown in (b) of FIG. 15. As a result, in the area of the sectional contact surface CS, the skirt portion 112 becomes thinner and less durable. The thick portion 1124 compensates for the thickness of the skirt portion 112 that becomes thinner due to the machining angle of the sectional contact surface CS.

[0064] FIG. 10 is a view showing a test probe 100 according to a fourth embodiment of the disclosure.

[0065] Referring to FIG. 10, a skirt portion 112A may be formed thicker than the barrel main body 111. In this case, like the skirt portion 112A, a portion of the barrel main body 111 adjacent to the bending portion TP of the skirt portion 112A may be formed thicker than the remaining portion of the barrel main body 111.

[0066] The skirt portions 112 (see FIG. 3) are longitudinally separated by the slits 113 in the lengthwise direction, and thus not durable. In the test probe 100 shown in FIG. 10, the skirt portion 112A is formed thicker than the barrel main body 111, thereby increasing the durability.

[0067] FIG. 11 is a view showing a test probe 100 according to a fifth embodiment of the disclosure, and FIG. 12 is a cross-sectional view taken along line B-B of FIG. 11.

[0068] Referring to FIGS. 11 and 12, the test probe 100 includes the barrel 110 and the plunger 120.

[0069] The barrel 110 includes at least one protrusion 114 protruding inwards. At least one protrusion 114 is formed along the bending portion TP and along a lengthwise extension line of the slit 113. The protrusion 114 may be formed by caulking between the barrel main body 111 and the slit 113 inwards from the outside of the barrel 110.

[0070] The plunger 120 includes a stepped portion 123a having a height difference between the sliding portion 121 and the terminal contact portion 122. The stepped portion 123a is caught in the protrusion 114 and prevented from falling out of the barrel main body 111.

[0071] FIG. 13 is a view showing a test probe 100 according to a sixth embodiment of the disclosure, and FIG. 14 is a view showing an operating state of the test probe 100 of FIG. 13.

[0072] Referring to FIG. 13, the plunger 120 includes the sliding portion 121 accommodated sliding in the barrel main body 111, and the terminal contact portion 122 extending from the sliding portion 121 and having a decreased diameter.

[0073] The terminal contact portion 122 includes a tapering portion 122T inclined to decrease the diameter toward the sliding portion 121, and a horizontal extending portion 122E extending from the tapering portion 122T and having a uniform diameter. The terminal contact portion 122 may include only the tapering portion 122T without the horizontal extending portion 122E.

[0074] The plunger 120 is outside the barrel main body 111 before the test. In this case, the sectional contact surface CS of the skirt portion 112 may be positioned on a surface corresponding to a small diameter within the outer surface of the tapering portion 122T. Therefore, the pressing force between the sectional contact surface CS of the skirt portion 112 and the outer diameter surface of the tapering portion 122T is relatively weak.

[0075] Referring to FIG. 14, the plunger 120 is inserted into the barrel main body 111 during the test. In this case, the sectional contact surface CS of the skirt portion 112 is positioned on the horizontal extending portion or on a surface corresponding to a large diameter within the outer diameter surface of the tapering portion 122T. In this way, the sectional contact surface CS of the skirt portion 112 may be in contact with the outer diameter surface of the tapering portion 122T with as little pressure as possible before the test, and come into contact with the outer diameter surface of the tapering portion 122T or the horizontal extending portion 122E with sufficient area and pressure during the test. In this way, the deformation of the skirt portion 112 remains for a short period of time before the test, thereby decreasing the fatigue of the bending portion TP of the skirt portion 112.

[0076] FIG. 15 is a schematic diagram showing a method of manufacturing a barrel 110 of FIG. 3.

[0077] In a first step, as shown in (a) of FIG. 15, a cylindrical pipe member 110M is formed of a conductive material. The pipe member 110M may include a flange 115.

[0078] In a second step, as shown in (b) of FIG. 15, a sectional contact surface CS is formed on an inner diameter surface at the first end portion of the pipe member 110M. The sectional contact surface CS is formed at an angle of 5 to 25 degrees to the lengthwise direction. The sectional contact surface CS may be machined by various methods such as chamfering, cutting, forging, and molding. The machining angle of the sectional contact surface CS is to make the sectional contact surface CS of the skirt portion 112 be substantially parallel to the terminal contact portion 122 in FIG. 3. The machining angle may be varied depending on the bending angle of the skirt portion, the outer diameter of the terminal contact portion 122, the outer diameter of the barrel 110, etc.

[0079] In a third step, as shown in (c) of FIG. 15, the slits 113 are formed in the first end portion of the pipe member 110M along the lengthwise direction at intervals. The number of slits 113 is not limited to four.

[0080] In fourth step, as shown in (d) of FIG. 15, the skirt portions 112 separated by the slits 113 are bent toward the central axis. In this case, the skirt portion 112 may have elasticity in a radial direction with respect to the central axis.

[0081] As an alternative embodiment, the steps may be reversed in order. In other words, the sectional contact surface CS in the second step may also be formed on the fore-end the inner diameter surface of the skirt portion 112 formed in the third step or the fore-end the inner diameter surface of the skirt portion 112 bent in the fourth step.

[0082] FIG. 16 is a schematic diagram showing a method of manufacturing the barrel 100 of FIG. 9.

[0083] In a first step, as shown in (a) of FIG. 16, a cylindrical pipe member 110M is formed of a conductive material. The pipe member 110M may include a flange 115.

[0084] In a second step, as shown in (b) of FIG. 16, the thick portion 1124 extending outwards in the radial direction is formed in the area of the sectional contact surface CS (to be described later). The thick portion 1124 may for example be formed by upset forging, molding, etc.

[0085] In a third step, as shown in (c) of FIG. 16, a sectional contact surface CS is formed on an inner diameter surface at the first end portion of the pipe member 110M. The sectional contact surface CS is formed at an angle of 5 to 25 degrees to the lengthwise direction. The sectional contact surface CS may be machined by chamfering, cutting, forging, molding, etc. The machining angle of the sectional contact surface CS is to make the sectional contact surface CS of the skirt portion 112 be substantially parallel to the terminal contact portion 122 in FIG. 3. The machining angle may be varied depending on the bending angle of the skirt portion, the outer diameter of the terminal contact portion 122, the outer diameter of the barrel 110, etc.

[0086] In a fourth step, as shown in (d) of FIG. 16, the slits 113 are formed in the first end portion of the pipe member 110M along the lengthwise direction at intervals. The number of slits 113 is not limited to four.

[0087] In fifth step, as shown in (e) of FIG. 16, the skirt portions 112 separated by the slits 113 are bent toward the central axis. In this case, the skirt portion 112 may have elasticity in a radial direction with respect to the central axis.

[0088] FIG. 17 is a schematic diagram showing a method of manufacturing the barrel 110 of FIG. 10.

[0089] In a first step, as shown in (a) of FIG. 17, a cylindrical pipe member 110M is formed of a conductive material. The pipe member 110M may include a flange 115.

[0090] In a second step, as shown in (b) of FIG. 17, the thickness of the area where the skirt portion 112T is formed is greater than the thickness of the barrel main body 111. The skirt portion 112T may for example be formed by upset forging, molding, etc.

[0091] In a third step, as shown in (c) of FIG. 17, a sectional contact surface CS is formed on an inner diameter surface at the first end portion of the pipe member 110M. The sectional contact surface CS is formed at an angle of 5 to 25 degrees to the lengthwise direction. The sectional contact surface CS may be machined by chamfering, cutting, forging, molding, etc. The machining angle of the sectional contact surface CS is to make the sectional contact surface CS of the skirt portion 112 be substantially parallel to the terminal contact portion 122 in FIG. 3. The machining angle may be varied depending on the bending angle of the skirt portion, the outer diameter of the terminal contact portion 122, the outer diameter of the barrel 110, etc.

[0092] In a fourth step, as shown in (d) of FIG. 17, the slits 113 are formed in the first end portion of the pipe member 110M along the lengthwise direction at intervals. The number of slits 113 is not limited to four.

[0093] In fifth step, as shown in (e) of FIG. 17, the skirt portions 112 separated by the slits 113 are bent toward the central axis. In this case, the skirt portion 112 may have elasticity in a radial direction with respect to the central axis.

[0094] FIG. 18 is a schematic diagram showing a process of assembling the test probe 100 according to the first embodiment of the disclosure.

[0095] In a first step, the barrel 110 having the skirt portion 112 is formed at the first end portion by the method of FIG. 15.

[0096] In a second step, the plunger 120 is inserted through the second end of the barrel 110 so that the terminal contact portion 122 can protrude through the skirt portion 112.

[0097] In a third step, the elastic body 140 is inserted in the barrel 110 through the second end of the barrel 110.

[0098] In a fourth step, the terminal 140 is partially inserted in and secured to the second end of the barrel 110. The terminal 130 may be secured by caulking (or punching) the barrel 110 at a position corresponding to the groove 131 of the terminal 130.

[0099] The test probe according to an embodiment of the disclosure includes the barrel main body, and the plurality of skirt portions spaced apart by the slits formed at the first end portion of the barrel main body in the lengthwise direction and decreased in diameter toward the central axis. The sectional contact surface formed in the fore-end area inner surface of each skirt portion to come into elastic contact with the outer diameter surface of the plunger throughout a predetermined lengthwise section maintains stable contact with the plunger during the test, thereby improving the reliability of the test.

[0100] The skirt portions are separated by the slits and thus described in durability. Therefore, the skirt portion is formed to be at least partially thicker than the barrel main body, thereby increasing the durability.

[0101] The inner diameter surface edges of the skirt portion are not in contact with the outer surface of the plunger so as to prevent the outer surface of the plunger from being scratched during the test.

[0102] At least a portion of the plunger to be in contact with the sectional contact surface may be formed to be decreased in diameter in a pressing direction during the test. Therefore, the skirt portion maintains the stable contact during the test, but is not in contact with the plunger or is in contact with the plunger with minimum pressure before the test, thereby improving the durability.

[0103] 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 comprising:a barrel comprising a tubular barrel main body, and a plurality of skirt portions formed in a first end portion of the barrel main body and spaced apart from each other by lengthwise slits; anda plunger comprising a sliding portion accommodated in the barrel main body, and a terminal contact portion extending from the sliding portion and exposed through the skirt portion to come into elastic contact with the skirt portion, whereinthe skirt portion comprises a skirt main body formed to be decreased in diameter having a partially conical shape along a direction from the barrel main body to a fore-end, and a skirt fore-end portion provided in a fore-end area of the skirt main body, andthe skirt fore-end portion comprises a sectional contact surface formed on an inner diameter surface thereof, with which an outer diameter surface of the terminal contact portion is in contact throughout a predetermined length section.2.The test probe of claim 1, wherein an area of the sectional contact surface comprises a thick portion extending outwards in a radial direction beyond the thickness of the skirt main body.3.The test probe of claim 1, wherein the skirt portion is thicker than the barrel main body.4.The test probe of claim 1, wherein the sectional contact surface is formed by chamfering or cutting.5.The test probe of claim 1, wherein a circumferential inner surface curvature of the sectional contact surface is smaller than a circumferential outer surface curvature of the terminal contact portion.6.A test probe comprising:a barrel comprising a tubular barrel main body, and a plurality of skirt portions formed in a first end portion of the barrel main body along a lengthwise direction and spaced apart from each other by slits; anda plunger comprising a sliding portion accommodated in the barrel main body, and a terminal contact portion extending from the sliding portion and exposed through the skirt portion to come into elastic contact with the skirt portion, whereinthe skirt portion comprises a skirt main body formed to be decreased in diameter having a partially conical shape along a direction from the barrel main body to a fore-end, and a skirt fore-end portion provided in a fore-end area of the skirt main body, andthe barrel main body comprises a protrusion protruding toward an inside of the barrel main body at an edge facing the slit.7.A test device comprising:the test probe of any one of claims 1 to 6; anda test socket supporting the test probe to make both end portions of the test probe partially protrude therefrom.

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