Test probe

Abstract

A test probe for testing an electrical characteristic of an object to be tested is disclosed. The test probe includes a cylindrical barrel including a plurality of main fixing protrusions protruding inward and facing each other, and includes a terminal including: a contact portion contacting an object to be tested; a fixing portion having a polygonal cross section, integrally extending from the contact portion and inserted in the first end portion of the barrel; and an engaging portion protruding from a first surface of the polygonal cross-section toward the main fixing protrusion, extending in a longitudinal direction of the fixing portion, and including a main fixing groove recessed to insert the main fixing protrusion therein.

Description

Technical Field

[0001] The present disclosure relates to a test probe for testing electrical characteristics of a device under test such as a semiconductor. Background Art

[0002] The test probe includes a cylindrical barrel, a first plunger partially inserted into and fixed to the first end of the barrel, a second plunger partially inserted into the second end of the barrel and movable slidably in the barrel, and a spring inserted into the barrel and providing elasticity to the second plunger. Each of the first plunger and the second plunger includes a cylindrical barrel insertion portion corresponding to the cylindrical barrel and a contact portion contacting a test contact point. To manufacture the first plunger and the second plunger, precision machining of a cylindrical substrate is required. However, the precision machining of the first plunger and the second plunger increases the manufacturing cost of the test probe. Summary of the Invention

[0003] Technical Problem

[0004] An embodiment of the present disclosure aims to provide a test probe with reduced manufacturing cost.

[0005] Means for Solving the Problem

[0006] According to an embodiment of the present disclosure, there is provided a test probe. The test probe includes a cylindrical barrel and includes a terminal. The barrel includes a plurality of main fixing protrusions protruding inwardly and facing each other. The terminal includes: a contact portion contacting the device under test; a fixing portion having a polygonal cross-section, integrally extending from the contact portion and inserted into a first end portion of the barrel; and a joining portion protruding from a first surface of the polygonal cross-section toward the main fixing protrusion, extending in a longitudinal direction of the fixing portion and including a main fixing groove in which the main fixing protrusion is inserted.

[0007] The fixing portion may include a sub-fixing groove recessed in the first surface, and the main fixing groove is located between the first surface and the sub-fixing groove in a direction transverse to the longitudinal direction.

[0008] The barrel may include a plurality of sub-fixing protrusions protruding inwardly, and the main fixing protrusion is located between the plurality of sub-fixing protrusions.

[0009] When the fixing portion rotates inside the barrel, the sub-fixing protrusion may be inserted into the sub-fixing groove.

[0010] The terminal may be manufactured by a microelectromechanical system (MEMS) process.

[0011] The terminal may include a plurality of cross-sectional layers having different cross-sections from each other.

[0012] The contact portion may include a contact tip that contacts the object to be tested, and the contact tip and the engagement portion may be disposed in one of the plurality of cross-sectional layers.

[0013] A protruding length of the main fixing protrusion may be in the range of 5% to 7% of a diameter of the barrel.

[0014] The protruding length of the engaging portion may be in the range of 7% to 10% of the diameter of the barrel.

[0015] The depth of the main fixing groove may be in the range of 4% to 5% of the diameter of the barrel.

[0016] Advantageous Effects of the Invention

[0017] The test probe according to the embodiment of the present disclosure can reduce manufacturing costs by applying terminals mass-produced through MEMS processes. In addition, the terminals can have a polygonal cross-sectional shape according to MEMS processes while being stably fixedly coupled to the cylindrical barrel. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a perspective view of a test probe according to an embodiment of the present disclosure.

[0019] Figure 2 yes Figure 1 Exploded perspective view of the test probe shown.

[0020] Figure 3 yes Figure 1 A perspective view of the terminals shown.

[0021] Figure 4 Is used to explain the manufacturing Figure 3 A view of the terminal approach shown.

[0022] Figure 5 It is shown along Figure 1 A perspective view of a cross section taken along line AA is shown.

[0023] Figure 6 It is along Figure 1 A cross-sectional view taken along line BB is shown.

[0024] Figure 7 It shows Figure 6 Cross-sectional view of the terminal rotated 45 degrees counterclockwise. DETAILED DESCRIPTION

[0025] The test probe according to the embodiment of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0026] Figure 1 is a perspective view of a test probe 1 according to an embodiment of the present disclosure, and Figure 2 is Figure 1 an exploded perspective view of the test probe 1 shown.

[0027] The test probe 1 includes a barrel 11, a terminal 12 inserted into and fixed to a first end portion of the barrel 11, a plunger 13 inserted into a second end portion of the barrel 11, and a spring 14 inserted into the barrel 11.

[0028] The barrel 11 is shaped like a hollow cylinder and made of a conductive material. The barrel 11 includes four fixing protrusions 111a and 111b radially formed in the first end portion of the barrel 11 and protruding inward from the first end portion. The four fixing protrusions 111a and 111b are arranged at intervals of about 90 degrees with respect to the circumferential surface of the barrel 11. The four fixing protrusions 111a and 111b can be formed by caulking, which punches the outer circumferential surface of the barrel 11 to be recessed inward. The four fixing protrusions 111a and 111b include a pair of main fixing protrusions 111a facing each other and a pair of sub-fixing protrusions 111b adjacent to and facing the main fixing protrusions 111a.

[0029] The terminal 12 is made of a conductive material and firmly coupled to the first end portion of the barrel 11 to contact a test contact point such as an object to be tested (e.g., a semiconductor). In this case, the firm coupling can be achieved by the coupling between the main fixing protrusion 111a of the barrel 11 and the main fixing groove 123c (to be described later) of the terminal 12. The terminal 12 will be described in detail later.

[0030] The plunger 13 is made of a conductive material and partially inserted into the second end portion of the barrel 11 to contact a test contact point such as a test circuit board. In this case, the plunger 13 can slide inside the barrel 11 while being partially inserted into the barrel 11. Since the second end portion of the barrel 11 is narrowed, the plunger 13 can move inside the barrel 11 but will not fall off the barrel 11.

[0031] The spring 14 is placed inside the barrel 11 and is compressed or restored as the plunger 13 slides, thereby providing elasticity to the plunger 13.

[0032] Figure 3 is Figure 1 a perspective view of the terminal 12 shown.

[0033] Referring to Figure 3 , the terminal 12 includes a body 121, a contact tip 122, and a pair of engaging portions 123.

[0034] The main body 121 includes a contact portion 121a that contacts the object to be tested and a fixing portion 121b that is inserted into the first end portion of the cylinder 11. The main body 121 has a polygonal cross-section, such as a rectangular cross-section, in a direction transverse to the longitudinal direction.

[0035] The contact portion 121a has an inclined end portion at the upper end portion of the contact portion 121a. The contact tip 122 is provided at the edge of the end portion of the contact portion 121a.

[0036] The diagonal length of the rectangular cross-section of the contact portion 121a is greater than the inner diameter of the cylinder 11. Therefore, the contact portion 121a is not inserted into the cylinder 11.

[0037] The fixing portion 121b extends integrally from the contact portion 121a. The fixing portion 121b has a substantially square cross-section. The diagonal length of the square cross-section of the fixing portion 121b is equal to or less than the inner diameter of the cylinder 11, such that the fixing portion 121b can be inserted into the cylinder 11.

[0038] The fixing portion 121b includes a pair of sub-fixing grooves 121c provided in a first surface and a second surface that face each other. When the terminal 12 rotates inside the cylinder 11, the pair of sub-fixing grooves 121c engage with the pair of sub-fixing protrusions 111b.

[0039] A stepped portion 121d is formed between the contact portion 121a and the fixing portion 121b. When the fixing portion 121b is inserted into the cylinder 11, the stepped portion 121d catches on the first end portion of the cylinder 11 and is prevented from entering the cylinder 11.

[0040] The pair of engaging portions 123 includes a pair of first engaging portions 123a that respectively protrude from a first surface and a second surface opposite the first surface of the contact portion 121a, and a pair of second engaging portions 123b that respectively protrude from a first surface and a second surface opposite the first surface of the fixing portion 121b toward the main fixing protrusion 111a of the cylinder 11. Each pair of the first engaging portions 123a and the second engaging portions 123b extends along the longitudinal direction on the first surface and the second surface opposite the first surface of the main body 121.

[0041] The pair of first engaging portions 123a are provided with the pair of main fixing grooves 123c at positions corresponding to the pair of main fixing protrusions 111a. When the outer circumferential surface of the cylinder 11 having the pair of main fixing grooves 123c is deformed by caulking to form the pair of main fixing protrusions 111a in a state where the fixing portion 121b is inserted into the first end portion of the cylinder 11, the fixing portion 121b is firmly coupled to the first end portion of the cylinder 11.

[0042] Figure 4 is a view for explaining a method of manufacturing Figure 3 the terminal 12 shown.

[0043] Referring to Figure 4 , the terminal 12 can be divided into three cross-sections Layer1 to Layer3 and manufactured by deposition and etching. In this way, the terminal 12 has a simple structure that can be manufactured by the fewest number of micro-electromechanical system (MEMS) processes.

[0044] The cross-section Layer1 refers to a pattern corresponding to a part of the body 121 manufactured by the first MEMS step.

[0045] The cross-section Layer2 refers to a pattern corresponding to a part of the body 121 (i.e., the contact tip 122 and the bonding part 123) manufactured by the first MEMS step.

[0046] The cross-section Layer3 refers to a pattern corresponding to the remaining part of the body 121 manufactured by the first MEMS step.

[0047] As described above, the terminal 12 for the test probe 1 can be mass-produced by MEMS processes.

[0048] Figure 5 is a perspective view showing a cross-section cut along Figure 1 the line A-A shown. Figure 6 is a cross-sectional view taken along Figure 1 the line B-B shown. Figure 7 is a view showing Figure 6 the terminal in

[0049] Referring to Figure 5 and 6 , the fixing part 121b is fixed to the cylinder 110 by the engagement between each pair of main fixing protrusions 111a and the main fixing groove 123c. Since the main fixing protrusion 111a has an elliptical curved shape on the inner side, it is difficult to maintain a stable engagement between the main fixing protrusion 111a and the main fixing groove 123c. During the test of the test probe 1, when the terminal 12 rotates counterclockwise inside the cylinder 11 (for example, rotates 45 degrees as shown in Figure 7 ), the engagement between each pair of main fixing protrusions 111a and the main fixing groove 123c is released, but the pair of sub-fixing protrusions 111b are respectively coupled to the pair of sub-fixing grooves 121b. Therefore, even if the terminal 12 rotates inside the cylinder 11, the terminal 12 is stably fixed and supported in the cylinder 11.

[0050] Since the fixing portion 121c of the terminal 12 is shaped like a quadrangular pillar, but the cylinder 11 has a circular hollow portion, there is inevitably a gap between the curved inner surface of the cylinder 11 and the surface of the fixing portion 121c. In order to fix the fixing portion 121c to the cylinder 11, a fixing groove is formed on the surface of the fixing portion 121c and a fixing protrusion to be inserted into the fixing groove is formed by caulking the outer circumferential surface of the cylinder 11. However, if the gap is too large, the amount of deformation (the protruding length L1 of the fixing protrusion) caused by the caulking in the cylinder 11 will also increase, resulting in the cylinder 11 becoming defective due to excessive deformation. To solve this problem, the terminal 12 according to the embodiment of the present disclosure includes a second engaging portion 123b protruding from the first surface of the fixing portion 121c and includes a main fixing groove 123c, so that the amount of deformation (the protruding length L1 of the fixing protrusion) caused by the caulking in the cylinder 11 can be reduced.

[0051] If the amount of deformation (the protruding length L1 of the fixing protrusion) caused by the caulking in the cylinder 11 is too small, the degree of engagement between the main fixing protrusion 111a and the main fixing groove 123c will also become too small, resulting in difficult stable and firm coupling.

[0052] For the firm coupling between the fixing portion 121c and the cylinder 11, the protruding length L1 of the main fixing protrusion 111a, the protruding length L2 of the second engaging portion 123b, and the depth D of the main fixing groove 123c should be set in an optimized manner based on the diameter R of the cylinder 11 as follows.

[0053] The protruding length L1 of the main fixing protrusion 111a can be in the range of 5% to 7% of the diameter R of the cylinder 11. When the protruding length L1 is less than 5% of the diameter R of the cylinder 11, the protruding length L2 of the second engaging portion 123b becomes longer and the width of the second engaging portion 123b becomes narrower, thereby reducing the durability of the second engaging portion 123b. On the other hand, when the protruding length L1 is greater than 7% of the diameter R of the cylinder 11, the durability of the second engaging portion 123b is improved, but the cylinder 11 may be damaged due to excessive deformation of the cylinder 11.

[0054] The protruding length L2 of the second engaging portion 123b can be in the range of 7% to 10% of the diameter R of the cylinder 11. When the protruding length L2 is less than 7% of the diameter R of the cylinder 11, the amount of deformation in the cylinder 11 becomes relatively large, resulting in the cylinder 11 being damaged. On the other hand, when the protruding length L2 is greater than 10% of the diameter R of the cylinder 11, the protruding length L2 of the second engaging portion 123b becomes longer and the width of the second engaging portion 123b becomes narrower, thereby reducing the durability of the second engaging portion 123b.

[0055] The depth D of the main fixing groove 123c may be within a range of 4% to 5% of the diameter R of the barrel 11. When the depth D of the main fixing groove 123c is less than 4% of the diameter R of the barrel 11, the degree of engagement between the elliptical main fixing protrusion 111a and the main fixing groove 123c is reduced, making it impossible to maintain a stable and secure coupling. When the depth D of the main fixing groove 123c is greater than 5% of the diameter R of the barrel 11, the width of the main fixing protrusion 111a becomes wider and the amount of deformation in the barrel 11 becomes greater, thereby causing damage to the barrel 11.

[0056] According to the embodiments of the present disclosure, the manufacturing cost of the test probe can be reduced by replacing the plunger fixed to the barrel with a terminal mass-produced by a MEMS process. In addition, the terminal with a polygonal cross-section manufactured based on the MEMS process can be stably and firmly coupled to the cylindrical barrel.

[0057] Although exemplary embodiments of the present disclosure have been shown and described, the present disclosure is not limited to the aforementioned specific embodiments. Those skilled in the art may implement various alternative modifications without departing from the scope of the present disclosure as claimed in the appended claims, and such modified embodiments should not be understood as being separated from the technical spirit or prospects of the present disclosure.

Claims

1. A test probe for testing the electrical characteristics of a test object, the test probe comprising: A cylindrical barrel including a plurality of main fixing protrusions protruding inwardly and facing each other; And A terminal, comprising: A contact portion that contacts the test object, A fixing portion having a polygonal cross-section, integrally extending from the contact portion and inserted into a first end portion of the barrel, and An engaging portion protruding from a first surface of the polygonal cross-section toward the main fixing protrusion, extending in a longitudinal direction of the fixing portion and including a recess for inserting the main fixing protrusion therein.

2. The test probe according to claim 1, wherein the fixing portion includes a sub-fixing groove recessed in the first surface, and the main fixing groove is located between the first surface and the sub-fixing groove in a direction transverse to the longitudinal direction.

3. The test probe according to claim 2, wherein the barrel includes a plurality of sub-fixing protrusions protruding inwardly, and the main fixing protrusions are located between the plurality of sub-fixing protrusions.

4. The test probe according to claim 3, wherein when the fixing portion rotates inside the barrel, the sub-fixing protrusions are inserted into the sub-fixing grooves.

5. The test probe according to claim 1, wherein the terminal is manufactured by a microelectromechanical system (MEMS) process.

6. The test probe according to claim 5, wherein the terminal includes a plurality of cross-sectional layers having different cross-sections from each other.

7. The test probe according to claim 6, wherein The contact portion includes a contact tip that contacts the test object, and The contact tip and the engaging portion are provided in one of the plurality of cross-sectional layers.

8. The test probe according to claim 1, wherein the protruding length of the main fixing protrusion is in the range of 5% to 7% of the diameter of the barrel.

9. The test probe according to claim 1, wherein the protruding length of the engaging portion is in the range of 7% to 10% of the diameter of the barrel.

10. The test probe according to claim 1, wherein the depth of the main fixing groove is in the range of 4% to 5% of the diameter of the barrel.

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