METHOD FOR MANUFACTURING A MEASUREMENT PROBE, AND MEASUREMENT PROBE

Abstract

The present disclosure provides a method for manufacturing a measurement probe, the method comprising cutting a carrier substrate to form a probe contour, the probe contour comprising at least one probe tip and a probe body, and metallizing the surface of the at least one probe tip of the probe contour. Further, the present disclosure provides a respective measurement probe.

Claims

1. A method, comprising: cutting a carrier substrate to form a probe contour, the probe contour comprising at least one probe tip and a probe body; forming the at least one probe tip by cutting the carrier substrate to provide a respective protrusion at least in a predefined plane that includes a plane of extension of the carrier substrate, wherein forming the at least one probe tip comprises at least one of laser cutting or milling a three-dimensional shape of the respective protrusion in the carrier substrate; and metallizing a surface of the at least one probe tip of the probe contour.

2. (canceled)

3. The method according to claim 1, wherein forming the at least one probe tip comprises at least one of laser cutting or milling an outer circumference of the respective protrusion.

4. (canceled)

5. The method according to claim 1, wherein the carrier substrate comprises a single-layer or multi-layer metallized printed circuit board carrier substrate.

6. The method according to claim 1, wherein the metallizing comprises metallizing the surface of the at least one probe tip with a metallization layer comprising a nickel palladium gold alloy.

7. The method according to claim 1, wherein the metallizing comprises coating the surface of the at least one probe tip with a metallization layer comprising a thickness of 10 μm to 50 μm.

8. The method according to claim 1, further comprising providing an electrical connection on the probe body to the at least one probe tip.

9. The method according to claim 8, wherein the electrical connection comprises a microstrip line or a coplanar line with a predetermined impedance.

10. The method according to claim 8, further comprising providing an electrical connector for the at least one probe tip on the probe body and electrically coupling the electrical connector to the electrical connection.

11. The method according to claim 8, further comprising providing in the electrical connection of the at least one probe tip or between the electrical connection and the at least one probe tip a resistor with a predetermined resistance value between 50 kOhms and 500 kOhms.

12. The method according to claim 11, wherein the resistor is provided as a surface-mounted device.

13. The method according to claim 12, wherein the resistor is provided at a distance of 0.1 mm to 1.5 mm from a contacting end of the at least one probe tip.

14. The method according to claim 11, wherein the resistor is provided as a printed resistor.

15. A measurement probe comprising: a carrier substrate in a form of a probe contour of the measurement probe, the probe contour comprising at least one probe tip and a probe body; and a metallization layer on a surface of the at least one probe tip; wherein the at least one probe tip comprises a respective protrusion at least in a predefined plane that includes a plane of extension of the carrier substrate, and wherein the respective protrusion is formed by at least one of laser cutting or milling a three-dimensional shape of the respective protrusion in the carrier substrate.

16. (canceled)

17. (canceled)

18. The measurement probe according to claim 15, wherein the carrier substrate comprises a single-layer or multi-layer metallized printed circuit board carrier substrate.

19. The measurement probe according to claim 15, wherein the metallization layer comprises at least one of a nickel palladium gold alloy or the metallization layer comprises a thickness of 10 μm to 50 μm.

20. The measurement probe according to claim 15, further comprising an electrical connection on the probe body to the at least one probe tip.

21. The measurement probe according to claim 20, wherein the electrical connection comprises a microstrip line or a coplanar line with a predetermined impedance.

22. The measurement probe according to claim 20, further comprising an electrical connector for the at least one probe tip on the probe body electrically coupled to the electrical connection.

23. The measurement probe according to claim 20, further comprising in the electrical connection of the at least one probe tip or between the electrical connection and the at least one probe tip a resistor with a predetermined resistance value with a resistance value between 50 kOhms and 500 kOhms.

24. The measurement probe according to claim 23, wherein the resistor comprises a surface-mounted device provided at a distance of 0.1 mm to 1.5 mm from a contacting end of the at least one probe tip.

25. The measurement probe according to claim 23, wherein the resistor comprises a printed resistor.

26. A measurement probe comprising: a carrier substrate in a form of a probe contour of the measurement probe, the probe contour comprising at least two probe tips, each with a respective probe body; and a metallization layer on a surface of the at least two probe tips.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0066] For a more complete understanding of the present disclosure and advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings. The disclosure is explained in more detail below using exemplary embodiments which are specified in the schematic figures of the drawings, in which:

[0067] FIG. 1 shows a schematic diagram of an embodiment of a measurement probe according to the present disclosure;

[0068] FIG. 2 shows a schematic diagram of an embodiment of a probe tip according to the present disclosure in a top view;

[0069] FIG. 3 shows a schematic diagram of the probe tip of FIG. 2 in a side view;

[0070] FIG. 4 shows a schematic diagram of another embodiment of a probe tip according to the present disclosure in top view;

[0071] FIG. 5 shows a schematic diagram of the probe tip of FIG. 4 in side view;

[0072] FIG. 6 shows a schematic diagram of another embodiment of a measurement probe according to the present disclosure;

[0073] FIG. 7 shows a schematic diagram of another embodiment of a measurement probe according to the present disclosure;

[0074] FIG. 8 shows a flow diagram of an embodiment of a method according to the present disclosure; and

[0075] FIG. 9 shows a flow diagram of an embodiment of another method according to the present disclosure.

[0076] In the figures like reference signs denote like elements unless stated otherwise.

DETAILED DESCRIPTION OF THE DRAWINGS

[0077] FIG. 1 shows a schematic diagram of a measurement probe 100. The measurement probe 100 comprises a carrier substrate 101 that is cut to comprise the desired probe contour of the measurement probe 100. On the carrier substrate 101 a probe tip 102 and a probe body 103 are formed as different sections or zones on the carrier substrate 101. In addition, the probe tip 102 comprises a metallization layer 104 that completely covers the probe tip 102.

[0078] The probe tip 102 of the measurement probe 100 may in an exemplary embodiment be formed by laser cutting or milling the probe contour on a planar carrier substrate 101. It is understood, that the cutting or milling may be performed in multiple steps. For example, in a first step specific details of the probe contour like e.g., the probe tip 102, may be formed. Then the metallization layer 104 may be provided and finally, the remaining parts of the probe contour may be formed. This manufacturing process allows handling the carrier substrate 101 easily while forming specific details like the probe tip 102, and then trimming the carrier substrate 101 into the final probe contour when most of the manufacturing is finished and no delicate handling processes need to be performed any more.

[0079] The carrier substrate 101 may in embodiments comprise a printed circuit board carrier substrate. It is understood, that especially a single-layer PCB material or multi-layer PCB material may be used.

[0080] The metallization layer 104 may in embodiments comprise a nickel palladium gold alloy. An alloy used in PCB manufacturing is electroless nickel electroless palladium immersion gold alloy, which may be used to provide the metallization layer 104. Depending on the intended application of the measurement probe 100, the metallization layer 104 may be dimensioned accordingly and may comprise a thickness of 10 μm to 50 μm. If the carrier substrate 101 is covered at least on one surface with copper, as may be the case for single-layer or multi-layer PCB material, the metallization layer 104 may be provided on the copper or the copper may be removed by a respective manufacturing process before applying the metallization layer.

[0081] The metallization layer 104 serves for contacting the DUT and picking up signals in the DUT that are to be measured. At the same time, with an adequate material like the above-mentioned alloy, the metallization layer 104 also provides mechanical stability to the probe tip.

[0082] FIG. 2 shows a schematic diagram a probe tip 202 in a top view. The probe tip 202 has the same contour as the probe tip 102 and is a two-dimensional probe tip 202.

[0083] Two-dimensional probe tips like the probe tip 202 may be formed easily with simple 2D cutting or milling processes that cut the contour of the respective probe tip 202 into the carrier substrate.

[0084] FIG. 3 shows the probe tip of FIG. 2 in a side view. It can be seen, that the probe tip 202 in the side view has an even thickness or a constant height.

[0085] FIG. 4 shows a schematic diagram of another embodiment of a probe tip 302 in a top view. The probe tip 302 comprises sections SE1-SE6 of different heights.

[0086] Section SE1 on the pointed end of the probe tip 302 has a first height, which is about half of the thickness of the carrier substrate used to form probe tip 302. Section SE2 has a thickness of about % of the thickness of the carrier substrate, and Section SE3 has the full thickness of the carrier substrate. The sections S1-S3 form a kind of upward slope at the pointed end of the probe tip 302.

[0087] Sections SE3, SE4 and SE5 represent the inverse pattern and form a downward slope. Section SE6 has the same height as the carrier substrate and serves to couple the probe tip 302 to a respective probe body.

[0088] It is understood, that similar structures may be provided on the bottom surface of the carrier substrate 301.

[0089] FIG. 5 shows probe tip 302 in a side view. In the side view it is obvious, that the sections SE1-SE5 on the pointed end of the probe tip 302 form a kind of ball-end for contacting the DUT.

[0090] It is understood, that the shown height profile is just exemplarily shown. In other embodiments, more or less steps may be used. In further embodiments, instead of orthogonal surfaces inclined surfaces may be formed e.g., by 3D-milling or the like.

[0091] FIG. 6 shows a schematic diagram of another measurement probe 400. The measurement probe 400 is based on the measurement probe 100. Therefore, the measurement probe 400 comprises a carrier substrate 401 as basis for forming probe bodies 403, 406, and probe tips 402, 405. It is understood, that the measurement probe 400 only exemplarily comprises two probe bodies 403, 406 with respective probe tips 402, 405. A measurement probe 400 with only one probe body and one probe tip is also possible. In other embodiments, a measurement probe 400 with more than two probe tips e.g., for measurement of a plurality of parallel signals, is also possible.

[0092] Both probe tips 402, 405 and probe bodies 403, 406 are identical but mirrored on the horizontal axis and coupled to each other by carrier substrate 401 on the end facing away from the probe tips 402, 405, forming a tweezer-like arrangement for the measurement probe 400. It is understood, that instead of uniting two or more probe bodies via a fixed piece of carrier substrate, separate measurement probes may be coupled to each other via a respective mechanical element, like for example a bracket or the like. Such an element may comprise a metallic or conductive material and the counterparts for the element on the measurement probes may be conductive or metallic and be coupled with a ground network of the respective measurement probe.

[0093] The probe tips 402, 405 are formed according to probe tip 102 and comprise a metallization layer 404, 405. On each of the probe bodies 403, 406 a respective electrical connection 410, 413 and a respective electrical connector 412, 415 is provided.

[0094] The electrical connections 410, 413 may be provided as microstrip lines with a predetermined impedance, like for example 50 Ohms. On one end the electrical connections 410, 413 couple to the respective electrical connector 412, 415. In the measurement probe 400 the electrical connectors 412, 415 are provided as RF-connectors, like for example Mini-SMP connectors. It is understood, that other connectors are possible

[0095] The electrical connections 410, 413 couple the respective electrical connector 412, 415 with the respective probe tip 402, 405. However, the electrical connections 410, 413 are not directly coupled to the respective probe tip 402, 405. Instead, a SMD resistor is provided between each of the electrical connections 410, 413 and the metallization layer 404, 405 of the respective probe tip 402, 405. The resistors may comprise a resistance value of about 50 kOhms to 500 kOhms, typically a resistance value between 100 kOhms and 200 kOhms may be used.

[0096] Although not shown, it is understood, that additional ground planes or ground zones may be provided on the probe bodies 403, 406 that may couple to a shield or ground contact of the respective electrical connector 412, 415.

[0097] FIG. 7 shows a schematic diagram of another possible measurement probe 500. The measurement probe 500 is based on the measurement probe 400. Therefore, the measurement probe 500 comprises a carrier substrate 501 as basis for forming probe bodies 503, 506, and probe tips 502, 505. It is understood, that the measurement probe 500 only exemplarily comprises two probe bodies 503, 506 with respective probe tips 502, 505. A measurement probe 500 with only one probe body and one probe tip is also possible. In other embodiments, a measurement probe 500 with more than two probe tips e.g., for measurement of a plurality of parallel signals, is also possible.

[0098] The probe tips 502, 505 are formed according to the probe tips 402, 405 and each comprise a metallization layer 504, 507. On each of the probe bodies 503, 506 a respective electrical connection 510, 513 and a respective electrical connector 512, 515 are provided.

[0099] The explanations regarding the measurement probe 400 apply to the measurement probe 500 mutatis mutandis.

[0100] In contrast to the SMD resistors of measurement probe 400, the measurement probe 500 comprises two printed resistors 511, 514 that couple the metallization layers 504, 507 to the respective one of the electrical connections 510, 513.

[0101] Printed resistors 511, 514 may easily be modelled according to the shape of the probe tips 502, 505. The distance between the outer edge of a probe tip 502, 505 and the printed resistor 511, 514 may therefore be reduced to a minimum. This arrangement consequently further reduces the negative influence of the measurement on the signal quality in the DUT.

[0102] The printed resistors 511, 514 may be formed as thick film resistors with a respective paste that may be printed onto the carrier substrate 501. Exact trimming of the resistance values may then be performed e.g., by laser trimming the printed resistors 511, 514.

[0103] FIG. 8 shows a flow diagram of a method for manufacturing a measurement probe.

[0104] The method comprises cutting S1 a carrier substrate to form a probe contour. As explained above, the probe contour comprises at least one probe tip with a respective probe body. The method further comprises metallizing S2 the surface of the at least one probe tip of the probe contour.

[0105] The carrier substrate may comprise a printed circuit board carrier substrate, like for example a single-layer or multi-layer metallized printed circuit board carrier substrate.

[0106] Cutting S1 may comprise forming the at least one probe tip by cutting the carrier substrate to provide a respective protrusion at least in a predefined plane, for example in the plane of extension of the carrier substrate. The forming of the at least one probe tip may be performed by laser cutting and/or milling the outer circumference of the protrusion to form a two-dimensional shape or contour. Alternatively, forming the at least one probe tip may comprise laser cutting and/or milling a three-dimensional shape of the respective protrusion to form a three-dimensional shape of the probe contour.

[0107] Metallizing S2 may comprise metallizing the surface of the at least one probe tip with a metallization layer comprising a nickel palladium gold alloy. A respective alloy may be an electroless nickel electroless palladium immersion gold alloy.

[0108] The process of metallizing may provide the surface of the at least one probe tip with a metallization layer comprising a thickness of 10 μm to 50 μm, especially 15 μm to 30 μm, or especially 15 μm to 20 μm.

[0109] FIG. 9 shows a flow diagram of another method for manufacturing a measurement probe. The method of FIG. 9 is based on the method of FIG. 8 and comprises cutting S1 a carrier substrate to form a probe contour. As explained above, the probe contour comprises at least one probe tip with a respective probe body. The method further comprises metallizing S2 the surface of the at least one probe tip of the probe contour.

[0110] In addition, the method of FIG. 9 comprises providing S3 an electrical connection on the probe body to the at least one probe tip, for example as a microstrip line or a coplanar line with a predetermined impedance, like 50 Ohms.

[0111] The method also comprises providing an electrical connector S4 for at least one of the probe tips on the probe body and electrically coupling the electrical connector to the respective electrical connection, and providing a resistor S5 in the electrical connection of the at least one probe tip with a predetermined resistance value. The resistance value may be between 50 kOhms and 500 kOhms.

[0112] The resistor may be provided as a surface-mounted device or may be provided as a printed resistor, especially a polymer thick film printed resistor.

[0113] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

LIST OF REFERENCE SIGNS

[0114]

TABLE-US-00001 100, 400, 500 measurement probe 101, 201, 401, 501 carrier substrate 102, 202, 302, 402, 405, 502, 505 probe tip 103, 403, 406, 503, 506 probe body 104, 404, 407, 504, 507 metallization layer 410, 413, 510, 513 electrical connection 411, 414, 511, 514 resistor 412, 415, 512, 515 electrical connector SE1, SE2, SE3, SE4, SES, SE6 section