Resistivity test probe head

Abstract

The utility model belongs to the technical field of resistivity test, and discloses a resistivity test probe head. The resistivity test probe head comprises a probe assembly and four conductive probes, the probe assembly comprises a probe and an elastic assembly, the probe is provided with an accommodating cavity and four penetrating holes, and the penetrating holes are communicated with the accommodating cavity; the elastic assembly is arranged in the containing cavity, and one end of the elastic assembly is connected to the inner wall of the containing cavity. The four conductive probes correspondingly pass through the four through holes and are connected with the other end of the elastic assembly. The bottom end passing surface of the conductive probe is in contact with the outer surface of the thin layer to be tested, so that the contact area of the conductive probe and the thin layer to be tested is increased, the pressure intensity is reduced, and test data errors caused by the fact that the probe pierces into a bottom layer material are avoided. The elastic assembly can enable the bottom end of the conductive probe to abut against the interior of the surface layer of the thin layer to be tested, the bottom end of the conductive probe is a horizontal plane or a curved surface, the abutting area of the conductive probe and the thin layer to be tested can be increased, stable contact of testing is guaranteed, and repeatability of testing data becomes good.

Description

Technical Field

[0001] The utility model relates to the technical field of resistivity testing, in particular to a resistivity testing probe head. Background Technique

[0002] The four-probe method is a method for measuring the resistivity of semiconductor materials. The resistivity is calculated by applying a current and measuring the voltage. A four-probe tester usually consists of four probes arranged in a straight line. One probe serves as a current source, another probe serves as a voltage measurement electrode, and the other two probes are used to measure current and voltage. During the measurement, the probes are placed on the surface of the semiconductor material, and a current is applied to measure the voltage drop between the probes. Through these measurement results, the resistivity can be calculated. During the development and production of semiconductor devices, it is often necessary to measure the thin-layer materials after the semiconductor has been processed by processes such as diffusion and epitaxy. The four-probe method is usually used to measure the resistivity of thin-layer materials because it can eliminate the influence of contact resistance and has high measurement accuracy.

[0003] When the prior art uses the four-probe method to test the resistivity of thin-layer materials, a conical probe is usually used for testing. When testing the surface layer material, the bottom end of the conical probe is the tip. Under the same load, the contact through a point with the thin-layer material will cause the probe pressure to be too high, resulting in the conical probe being inserted too deep and easily penetrating into the underlying material below the surface layer material. This will cause the test current to flow through the underlying material below, resulting in incorrect test data. In addition, the test material is often doped to improve the device performance. After low-doping certain elements in the surface layer material, the concentration of ions in the surface layer becomes low. During the test, since the conical probe contacts the surface layer material through a point, the contact opportunity between the probe and the ions in the surface layer is reduced, resulting in poor conductivity between the probe and the ions inside the surface layer, poor repeatability of the test data, and even inability to measure the value. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a resistivity testing probe head, which avoids the occurrence of incorrect test data caused by the probe penetrating into the underlying material and can solve the problem of poor repeatability of test data during low-doping testing.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A resistivity testing probe head, comprising:

[0007] A probe assembly, including a probe and an elastic component. The probe is provided with a receiving cavity and four through holes, and the through holes communicate with the receiving cavity; the elastic component is arranged in the receiving cavity and one end is connected to the inner wall of the receiving cavity;

[0008] Four conductive probes are provided in one-to-one correspondence with the four through holes. The four conductive probes respectively pass through the four through holes and are all connected to the other end of the elastic component. The bottom end of the conductive probe is a horizontal plane or a curved surface, and the bottom end of the conductive probe contacts the outer surface of the thin layer to be tested through a surface. The elastic component can press the bottom end of the conductive probe tightly within the surface layer of the thin layer to be tested.

[0009] In some possible implementation manners, the conductive probe includes a needle body and a needle head which are integrally arranged, and the needle head is located at the bottom end of the needle body.

[0010] In some possible implementation manners, both the needle body and the needle head are of a cylindrical structure, and the bottom end of the needle head is a horizontal plane.

[0011] In some possible implementation manners, the cross-sectional size of the needle body is larger than the cross-sectional size of the needle head.

[0012] In some possible implementation manners, the elastic component includes four elastic members which are provided in one-to-one correspondence with the four conductive probes. One end of the elastic member is fixedly connected to the inner wall of the accommodation cavity of the probe head, and the other end of the elastic member is fixedly connected to the conductive probe.

[0013] In some possible implementation manners, the material of the elastic member is a conductive material, and the probe head assembly further includes a connecting wire which is electrically connected to the elastic member.

[0014] In some possible implementation manners, the elastic member is a spring.

[0015] In some possible implementation manners, the conductive probe is slidably connected to the through hole.

[0016] In some possible implementation manners, the probe head includes a probe head body and a sleeve. The sleeve is inserted and clamped into the probe head body, and the inner hole of the sleeve is the through hole.

[0017] In some possible implementation manners, the probe head body includes a first connecting body and a second connecting body. The first connecting body and the second connecting body are detachably connected, and the sleeve is inserted and clamped into the second connecting body.

[0018] Advantages of the present utility model:

[0019] The resistivity test probe head provided by the present utility model includes a probe assembly and four conductive probes. The probe assembly includes a probe and an elastic component. The bottom end of the conductive probe is a horizontal plane or a curved surface. When the bottom end of the conductive probe enters the outer surface of the thin layer to be tested, the bottom end of the conductive probe contacts the outer surface of the thin layer to be tested through a surface, increasing the contact area between the conductive probe and the thin layer to be tested, reducing the pressure, making the penetration depth of the probe shallower, and avoiding the occurrence of incorrect test data caused by the probe penetrating into the underlying material. During the test, the elastic component can press the bottom end of the conductive probe tightly within the surface layer of the thin layer to be tested. The bottom end of the conductive probe is a horizontal plane or a curved surface, increasing the pressing area between the conductive probe and the thin layer to be tested, improving the contact opportunity between the conductive probe and the ions within the surface layer, and further improving the conductivity between the conductive probe and the ions within the surface layer, ensuring stable test contact and solving the problem of poor repeatability of test data during low-doping tests. Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of the resistivity test probe head provided by the present utility model from a first perspective;

[0021] Figure 2 is a schematic structural diagram of the conductive probe involved in the present utility model;

[0022] Figure 3 is a schematic diagram of the state when the conductive probe involved in the present utility model tests the thin layer to be tested;

[0023] Figure 4 is a schematic structural diagram of the resistivity test probe head provided by the present utility model from a second perspective.

[0024] In the figure:

[0025] 1. Probe assembly; 11. Probe body; 111. First connecting body; 112. Second connecting body; 12. Sleeve; 121. Through hole; 13. Probe cover; 131. Wire outlet; 14. Elastic component; 141. Elastic member; 1411. First welding point; 1412. Second welding point; 15. Connecting wire;

[0026] 2. Conductive probe; 21. Needle body; 22. Needle tip;

[0027] 100. Thin layer to be tested; 101. Surface layer; 102. Underlying layer. Detailed Embodiment

[0028] The present utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only for explaining the present utility model and not for limiting the present utility model. Additionally, it should be noted that for the sake of description, only the parts related to the present utility model rather than all the structures are shown in the drawings.

[0029] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0030] In the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over", and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "under", and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.

[0031] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meanings.

[0032] Such as Figures 1 to 4As shown in the figure, the present utility model provides a resistivity test probe head, which is suitable for advanced process technology and can meet the test requirements for thinner and softer thin-layer materials. The thin layer 100 to be tested includes a surface layer 101 and a bottom layer 102. When measuring the resistivity of the surface layer 101 during the test, the resistivity test probe head can ensure the accuracy of the resistivity test result. The resistivity test probe head includes a probe assembly 1 and four conductive probes 2. The probe assembly 1 includes a probe and an elastic component 14. The probe is provided with a receiving cavity and four through holes 121, and the through holes 121 communicate with the receiving cavity; the elastic component 14 is arranged in the receiving cavity and one end is connected to the inner wall of the receiving cavity; the four conductive probes 2 are arranged in one-to-one correspondence with the four through holes 121, and the four conductive probes 2 respectively pass through the four through holes 121 and are all connected to the other end of the elastic component 14; the bottom end of the conductive probe 2 is a horizontal plane or a curved surface, and the bottom end of the conductive probe 2 contacts the outer surface of the thin layer 100 to be tested through a surface, and the elastic component 14 can press the bottom end of the conductive probe 2 against the surface layer 101 of the thin layer 100 to be tested. The bottom end of the conductive probe 2 is a horizontal plane or a curved surface. When the bottom end of the conductive probe 2 enters the outer surface of the thin layer 100 to be tested, the bottom end of the conductive probe 2 contacts the outer surface of the thin layer 100 to be tested through a surface, increasing the contact area between the conductive probe 2 and the thin layer 100 to be tested, reducing the pressure, making the penetration depth of the probe shallower, and avoiding the occurrence of incorrect test data caused by the probe penetrating into the bottom layer 102. During the test, the elastic component 14 can press the bottom end of the conductive probe 2 against the surface layer 101 of the thin layer 100 to be tested. The bottom end of the conductive probe 2 is a horizontal plane or a curved surface, increasing the pressing area between the conductive probe 2 and the thin layer 100 to be tested, improving the contact opportunity between the conductive probe 2 and the ions in the surface layer 101, and further improving the conductivity between the conductive probe 2 and the ions inside the surface layer 101, ensuring stable test contact and solving the problem of poor repeatability of test data during low-doping tests.

[0033] Optionally, in this embodiment, as Figure 2 shown, the conductive probe 2 includes a needle body 21 and a needle tip 22 which are integrally arranged, and the needle tip 22 is located at the bottom end of the needle body 21. Integrally arranging the needle body 21 and the needle tip 22 is convenient for processing. Optionally, in other embodiments, the needle body 21 and the needle tip 22 are detachably connected, which is convenient for installation. Specifically, the needle body 21 is provided with an internal threaded hole, and the needle tip 22 is provided with an external thread, and the external thread is threadedly connected to the internal threaded hole; or, the needle body 21 is provided with a clamping hole, and the needle tip 22 is provided with a clamping portion, and the clamping portion is clamped with the clamping hole.

[0034] Optionally, in this embodiment, both the needle body 21 and the needle tip 22 are cylindrical structures, and the bottom end of the needle tip 22 is a horizontal plane, which is convenient for processing. Moreover, when the bottom end of the conductive probe 2 enters the outer surface of the thin layer 100 to be tested, the entire surface of the bottom end of the conductive probe 2 contacts the outer surface of the thin layer 100. Compared with the case where the bottom end of the needle tip 22 is a curved surface and the curved surface contacts the outer surface of the thin layer 100 through a partial surface, the contact area is larger.

[0035] Optionally, in this embodiment, the cross-sectional size of the needle body 21 is larger than that of the needle tip 22. This saves materials and facilitates the entry of the needle tip 22 into the thin layer 100 to be tested. Optionally, in other embodiments, the cross-sectional size of the needle body 21 is equal to that of the needle tip 22.

[0036] Optionally, in this embodiment, both the needle body 21 and the needle tip 22 are made of tungsten, which has high hardness and good electrical conductivity.

[0037] Optionally, in this embodiment, the conductive probe 2 is slidably connected to the through hole 121. During the process of the spring assembly driving the conductive probe 2 to move up and down, it plays a role of guiding and limiting, avoiding errors brought by lateral movement to the test.

[0038] Optionally, in this embodiment, the probe includes a probe body 11 and a sleeve 12. The sleeve 12 is inserted and clamped into the probe body 11, and the inner hole of the sleeve 12 is the through hole 121. Different sizes of sleeves 12 can be replaced according to the size of the conductive probe 2 to meet the test requirements, and it is convenient for disassembly and installation. Optionally, in this embodiment, the sleeve 12 is a ruby bushing, which is wear-resistant and can achieve accurate positioning.

[0039] Optionally, in this embodiment, the probe body 11 includes a first connection body 111 and a second connection body 112. The first connection body 111 and the second connection body 112 are detachably connected, and the sleeve 12 is inserted and clamped into the second connection body 112. Detachably connecting the first connection body 111 and the second connection body 112 is convenient for installation and storage. Specifically, an internal threaded hole is provided on the first connection body 111, and an external thread is provided on the second connection body 112, and the external thread is threadedly connected to the internal threaded hole; alternatively, a clamping hole is provided on the first connection body 111, and a clamping portion is provided on the second connection body 112, and the clamping portion is clamped with the clamping hole.

[0040] Optionally, in this embodiment, the elastic component 14 includes four elastic members 141, and the four elastic members 141 are arranged in one-to-one correspondence with the four conductive probes 2. One end of the elastic member 141 is fixedly connected to the inner wall of the accommodation cavity of the probe head, and the other end of the elastic member 141 is fixedly connected to the conductive probe 2. For the four conductive probes 2, four elastic members 141 are respectively arranged correspondingly to ensure uniform force, and when the bottom end of the conductive probe 2 is pressed tightly against the thin layer 100 to be tested, the pressing effect is good. Optionally, the material of the elastic member 141 is a conductive material, and the probe head assembly 1 further includes a connecting wire 15, and the connecting wire 15 is electrically connected to the elastic member 141. With such a setting, wire materials are saved and the occupied space is small. Alternatively, the connecting wire 15 is directly electrically connected to the conductive probe 2. Optionally, in this embodiment, the elastic member 141 is a spring.

[0041] Optionally, in this embodiment, the probe head further includes a probe head cover 13, and the probe head cover 13 is covered on the first connecting body 111. The probe head cover 13 and the inner cavity of the first connecting body 111 enclose an accommodation cavity, and one end of the elastic member 141 is fixedly connected to the bottom of the probe head cover 13. The probe head cover 13 is provided to play a role of protection and sealing. Optionally, one end of the elastic member 141 is welded to the bottom of the probe head cover 13 through a first welding point 1411, and the other end of the elastic member 141 is welded to the conductive probe 2 through a second welding point 1412. With such a setting, the structure is compact and the installation is convenient. During installation, after welding the two ends of the elastic member 141 to the probe head cover 13 and the conductive probe 2 respectively, then cover the probe head cover 13 on the probe head body 11.

[0042] Optionally, the probe head cover 13 further includes a wire outlet portion, and the connecting wire 15 passes through the wire outlet portion and extends out from the wire outlet 131 of the wire outlet portion. The wire outlet portion is provided to enable the connecting wire 15 to be connected to an external power source through the wire outlet portion.

[0043] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limiting the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A resistivity test probe head, characterized in that, Comprising: A probe assembly (1), including a probe and an elastic assembly (14), the probe is provided with a receiving cavity and four through holes (121), and the through holes (121) communicate with the receiving cavity; the elastic assembly (14) is arranged in the receiving cavity, and one end is connected to the inner wall of the receiving cavity; Four conductive probes (2), which are arranged in one-to-one correspondence with the four through holes (121), the four conductive probes (2) correspondingly pass through the four through holes (121) and are all connected to the other end of the elastic assembly (14); the bottom end of the conductive probe (2) is a horizontal plane or a curved surface, and the bottom end of the conductive probe (2) contacts the outer surface of the thin layer to be tested (100) through a surface, and the elastic assembly (14) can press the bottom end of the conductive probe (2) tightly in the surface layer (101) of the thin layer to be tested (100).

2. The resistivity test probe head according to claim 1, characterized in that, The conductive probe (2) includes an integrally arranged needle body (21) and a needle head (22), and the needle head (22) is located at the bottom end of the needle body (21).

3. The resistivity test probe head according to claim 2, characterized in that, Both the needle body (21) and the needle head (22) are cylindrical structures, and the bottom end of the needle head (22) is a horizontal plane.

4. The resistivity test probe head according to claim 2, characterized in that, The cross-sectional size of the needle body (21) is larger than the cross-sectional size of the needle head (22).

5. The resistivity test probe head according to claim 1, characterized in that, The elastic assembly (14) includes four elastic members (141), the four elastic members (141) are arranged in one-to-one correspondence with the four conductive probes (2), one end of the elastic member (141) is fixedly connected to the inner wall of the receiving cavity of the probe, and the other end of the elastic member (141) is fixedly connected to the conductive probe (2).

6. The resistivity test probe head according to claim 5, characterized in that, The material of the elastic member (141) is a conductive material, and the probe assembly (1) further includes a connecting wire (15), and the connecting wire (15) is electrically connected to the elastic member (141).

7. The resistivity test probe head according to claim 5, wherein, The elastic member (141) is a spring.

8. The resistivity test probe head according to claim 1, characterized in that, The conductive probe (2) is slidably connected to the through hole (121).

9. The resistivity test probe head according to claim 8, wherein, The probe includes a probe body (11) and a sleeve (12), the sleeve (12) is inserted and clamped into the probe body (11), and the inner hole of the sleeve (12) is the through hole (121).

10. The resistivity test probe head according to claim 9, wherein, The probe body (11) includes a first connecting body (111) and a second connecting body (112), the first connecting body (111) is detachably connected to the second connecting body (112), and the sleeve (12) is inserted and clamped into the second connecting body (112).

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