Detection probe and detection device

Abstract

According to the detection probe and the detection device provided by the invention, the power-on detection of the diode is realized through the probe and the flexible conductor, the damage to the electrode is greatly reduced, meanwhile, the detection efficiency is improved, and the cost and the loss are reduced. The detection probe may include a first portion and a second portion. At least one of the first portion and the second portion may be a flexible conductor, and the first portion and the second portion are disposed adjacent to each other. The flexible electrical conductor may be used to contact the first electrode of the diode. The probe may be used to contact the second electrode of the diode.

Description

Technical Field

[0001] The present application relates to the field of wafer detection technology, and more particularly, to a detection probe and a detection device. Background Art

[0002] With the rapid advancement of semiconductor technology, semiconductor devices such as diodes integrated on wafers (such as microlight-emitting diodes (micro-LEDs)) are increasingly becoming highly integrated and miniaturized. Each diode on the wafer requires power-on testing to determine if it is a good product. Due to the large number of diodes integrated on a wafer and the small size of the electrodes (positive or negative) in the diodes, efficient and stable power-on testing of these electrodes is a pressing technical challenge.

[0003] The detection probe provided by the related art is equipped with a large number of probes, which are directly in contact with the electrodes to achieve the power-on detection of the diode. On the one hand, the probes can easily damage the electrodes, and on the other hand, the detection efficiency is low. The large number of probes leads to high costs and large losses. Summary of the Invention

[0004] In order to overcome the above-mentioned shortcomings, the present application provides a detection probe and a detection device, which realize power-on detection of the diode through a flexible conductor, greatly reducing damage to the electrode, while improving detection efficiency and reducing costs and losses.

[0005] In a first aspect, the present application provides a detection probe that may include a first portion and a second portion. At least one of the first portion and the second portion may be a flexible conductor, and the first portion and the second portion are disposed adjacent to each other. The flexible conductor may be configured to contact a first electrode of a diode. The probe may be configured to contact a second electrode of the diode. Optionally, the first electrode may be a positive electrode / negative electrode, and the second electrode may be a negative electrode / positive electrode.

[0006] In the detection probe provided in the present application, the first part can contact one of the positive electrode and the negative electrode, and the second part can contact one of the negative electrode and the positive electrode. The power-on detection of the diode is realized through a flexible conductor, which greatly reduces the damage to the electrode, while improving the detection efficiency and reducing the detection cost and loss.

[0007] In a possible implementation, the flexible conductor may include a main body portion and a conductive portion, wherein the conductive portion is mixed in the main body portion, or the conductive portion is sprayed on the surface of the main body portion.

[0008] For example, the main body may be elastic, the conductive part may be conductive, the main body may be made of rubber or silicone, and the conductive part may be made of conductive particles or metal paste.

[0009] For example, the flexible conductor may be rubber mixed with conductive particles, or may be silicone sprayed with metal slurry.

[0010] For another example, the flexible conductor may be silicone mixed with conductive particles, or rubber sprayed with metal slurry.

[0011] Of course, the main body part and the conductive part can also be of other types, which is not limited in this application.

[0012] Furthermore, the conductive particles and the metal paste may each include at least one of copper, silver, or gold.

[0013] For example, the conductive particles may include copper particles, silver particles, or gold particles. Of course, the conductive particles may also include other conductive elements, which is not limited in this application.

[0014] Similarly, the metal paste may include copper paste, silver paste or gold paste. Of course, the metal paste may also include other conductive elements, which is not limited in this application.

[0015] For example, the average spacing between the conductive particles can be less than or equal to 50 μm, and the surface roughness of the flexible conductor can be less than or equal to 20 μm. The volume resistivity of the flexible conductor can be less than or equal to 0.1 Ω·cm. Relatively small average spacing between the conductive particles, surface roughness, and volume resistivity can improve the conductivity of the flexible conductor and enhance detection accuracy.

[0016] For example, there may be multiple first electrodes and multiple second electrodes. That is, there may be multiple diodes on the wafer. The multiple first electrodes may be arranged in a matrix, and the multiple second electrodes may be electrically connected.

[0017] Optionally, the compressed dimension of the flexible conductor in the first direction may be greater than the maximum dimension difference between any two first electrodes in the first direction, so that the flexible conductor is in full contact with all first electrodes as much as possible, thereby improving detection accuracy.

[0018] In a second aspect, the present application provides a detection device, which may include a power supply, a processing unit, and a detection probe provided by the first aspect and its possible implementations. The processing unit and the detection probe may both be electrically connected to the power supply.

[0019] The power supply can be used to supply power to the diode through the detection probe, and can also be used to obtain electrical information of the diode through the detection probe, where the electrical information can be voltage, current, etc.

[0020] The processing unit can be used to determine whether the diode passes the test based on the electrical information and a preset threshold range. In other words, the processing unit can determine whether the diode is a good product based on the electrical information and a preset threshold range.

[0021] In a possible implementation, the detection device may further include a metal indenter, which may be electrically connected to a power source, and the flexible conductor may be integrated with the metal indenter, or the flexible conductor may be fixed to the metal indenter.

[0022] The metal pressing head can be used to support the flexible conductor and apply pressure to the flexible conductor so that the flexible conductor is in full contact with the first electrode.

[0023] It can be seen that the metal indenter not only supports the flexible conductor, but also ensures that the flexible conductor is in full contact with the first electrode, thereby improving the detection accuracy of the detection device.

[0024] Optionally, the flexible conductor can be fixed to the metal pressure head by a conductive material or by vulcanization. The conductive material can be a conductive adhesive, etc. Of course, the flexible conductor can also be fixed by other means, which is not limited in this application.

[0025] In one possible implementation, the diode may be a light-emitting diode (micro-LED). Thus, the detection device may further include an image acquisition unit. The image acquisition unit may be located on the light-emitting side of the light-emitting diode. The light-emitting side may be used to indicate the side of the light-emitting diode that is away from the flexible conductor.

[0026] The image acquisition unit can be used to acquire image information of the light emitting diode and output it to the processing unit.

[0027] The processing unit can also be used to determine whether the light emitting diode passes the test based on the electrical information, the preset threshold range, and the image information. In other words, the processing unit can determine whether the light emitting diode is a good product based on the electrical information, the preset threshold range, and the image information.

[0028] Furthermore, the detection device may further include a carrier, and the carrier is used to carry the diode, that is, to carry the wafer having the diode.

[0029] Optionally, in a scenario where the diode detected by the detection device is a light-emitting diode, the carrier may be a transparent carrier, so that the image acquisition unit can acquire image information.

[0030] It should be understood that the second aspect of this application is consistent with the technical solution of the first aspect of this application, and the beneficial effects achieved by each aspect and the corresponding feasible implementation methods are similar, which will not be repeated. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the present application or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 This is a schematic structural diagram of a detection device in an embodiment of the present application;

[0033] Figure 2 This is a schematic structural diagram of a detection device in an embodiment of the present application;

[0034] Figure 3 This is a schematic diagram of image information in an embodiment of the present application. DETAILED DESCRIPTION

[0035] The technical solution in this application will be described below with reference to the accompanying drawings.

[0036] To make the objectives, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0037] The terms "first," "second," and the like in the description, embodiments, claims, and drawings of this application are used solely for descriptive purposes and are not to be construed as indicating or implying relative importance or order. Furthermore, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions, such as, for example, inclusion of a series of steps or units. A method, system, product, or apparatus is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0038] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0039] With the rapid development of semiconductor technology, semiconductor devices such as diodes integrated on wafers (such as microlight-emitting diodes (micro-LEDs)) are gradually moving towards high integration and miniaturization. Each diode on the wafer needs to undergo power-on testing to determine whether it is a good product. Due to the large number of diodes integrated on the wafer and the small size of the electrodes in the diodes (denoted by E, which can be either positive or negative electrodes), how to efficiently and stably perform power-on testing on the electrodes is a technical problem that needs to be solved urgently.

[0040] The detection probe provided by the related art is equipped with a large number of probes, which are directly in contact with the electrodes to achieve the power-on detection of the diode. On the one hand, the probes can easily damage the electrodes, and on the other hand, the detection efficiency is low. The large number of probes leads to high costs and large losses.

[0041] In order to overcome the above shortcomings, the embodiment of the present application provides a detection probe for detecting multiple diodes on multiple wafers. Figure 1 As shown. The detection probe 10 may include a first portion and a second portion. The first portion and the second portion are disposed adjacent to each other, and at least one of the first portion and the second portion may be a flexible conductor. In other words, the first portion and the second portion may both be flexible conductors, or one of them may be a flexible conductor. In the embodiment of the present application, the first portion may be the flexible conductor 1, and the second portion may be the probe 2.

[0042] The flexible conductor 1 can be used to contact the first electrode E1 of the diode. The probe 2 can be used to contact the second electrode E2 of the diode. The first electrode E1 can be a positive electrode / negative electrode, and the second electrode E2 can be a negative electrode / positive electrode.

[0043] Since there may be multiple diodes on the wafer W, each diode may have a first electrode E1 and a second electrode E2. In other words, there may be multiple first electrodes E1 and multiple second electrodes E2 on the wafer W. In the embodiment of the present application, Figure 1 , the first electrode E1 is a positive electrode, the second electrode E2 is a negative electrode, and a plurality of first electrodes E1 are arranged in a matrix and a plurality of second electrodes E2 are electrically connected. The spacing between the plurality of first electrodes E1 can be less than or equal to 50 μm. The diameter of the first electrode E1 and the second electrode E2 can be 20 μm. Since the plurality of second electrodes E2 are electrically connected, Figure 1 Only one second electrode is shown. Of course, multiple negative electrodes can also be arranged in a matrix and multiple positive electrodes can be electrically connected.

[0044] In the detection probe 10 provided in the embodiment of the present application, the probe 2 can contact the second electrode E2, and the flexible conductor 1 can contact the first electrode E1. The power-on detection of the diode is realized through the probe 2 and the flexible conductor 1. Since only part of the electrode (i.e., the second electrode E2) is in contact with the probe 2, the damage to the second electrode E2 is greatly reduced, and the detection efficiency is improved, and the detection cost and loss are reduced.

[0045] In some embodiments, the flexible conductor 1 may include a main body portion and a conductive portion. The conductive portion may be mixed into the main body portion, or the conductive portion may be sprayed on the surface of the main body portion.

[0046] For example, the main body may be elastic, the conductive part may be conductive, the main body may be made of rubber or silicone, and the conductive part may be made of conductive particles or metal paste.

[0047] For example, the flexible conductor 1 may be rubber mixed with conductive particles, or may be silicone sprayed with metal slurry.

[0048] For another example, the flexible conductor 1 may also be silicone mixed with conductive particles, or rubber sprayed with metal slurry.

[0049] Of course, the main body part and the conductor part can also be of other types, which is not limited in the embodiment of the present application.

[0050] Furthermore, the conductive particles and the metal paste may each include at least one of copper, silver, or gold.

[0051] For example, the conductive particles may include copper particles, silver particles, or gold particles. Of course, the conductive particles may also include other conductive elements, which is not limited in the present embodiment.

[0052] Similarly, the metal paste may include copper paste, silver paste, or gold paste. Of course, the metal paste may also include other conductive elements, which is not limited in the present embodiment.

[0053] For example, the average spacing between the conductive particles can be less than or equal to 50 μm, and the surface roughness of the flexible conductor 1 can be less than or equal to 20 μm. The volume resistivity of the flexible conductor 1 can be less than or equal to 0.1 Ω·cm. The relatively small average spacing between the conductive particles, surface roughness, and volume resistivity can improve the conductivity of the flexible conductor 1 and enhance detection accuracy.

[0054] In this embodiment of the present application, the average spacing between the conductive particles can be less than 15 μm, and the surface roughness of the flexible conductor 1 can be less than 5 μm. The volume resistivity of the flexible conductor 1 can be less than 0.004 Ω·cm, and the tensile strength of the flexible conductor 1 can be greater than or equal to 1.8 MPa. As can be seen, in this embodiment of the present application, the dense concentration of conductive particles ensures that the flexible conductor 1 contacts all first electrodes simultaneously as much as possible, while also ensuring the conductivity of the flexible conductor 1 in all directions.

[0055] Optionally, the flexible conductor 1 can be configured as a cylinder, a cube (rectangular parallelepiped or square cube) according to specific application scenarios. In order to meet the power-on requirements of a plane, in the embodiment of the present application, the flexible conductor 1 can be a cube.

[0056] In other embodiments, the compressed dimension of the flexible conductor 1 in the first direction (which may be the thickness direction) (i.e., the compressed height of the flexible conductor 1) is greater than the maximum dimension difference between any two first electrodes E1 in the first direction. In other words, the heights of the multiple first electrodes E1 can be the same or different. There will be a height difference between first electrodes E1 of different heights, and there will be multiple height differences between the multiple first electrodes E1, with a maximum height difference among the multiple height differences. Therefore, the compressed height of the flexible conductor 1 is greater than the maximum height difference between different first electrodes E1, which can ensure that the flexible conductor 1 is in full contact with all first electrodes E1 as much as possible, thereby improving detection accuracy.

[0057] Alternatively, the probe 2 may be made of metal materials such as copper, tungsten, etc. Of course, the probe 2 may also be made of alloy materials. In order to improve stability, two or more probes may be arranged around the flexible conductor 1 .

[0058] The present application also provides a detection device, such as Figure 2 The detection device 100 may include a detection probe 10 , a carrier 20 , a power supply 30 and a processing unit 40 .

[0059] The processing unit 40 can be electrically connected to the power supply 30. The positive terminal of the power supply 30 can be electrically connected to the flexible conductor 1, and the negative terminal of the power supply 30 can be electrically connected to the probe 2. The carrier 20 can be used to support the diode, that is, to support the wafer W with the diode.

[0060] The power supply 30 can be used to power the diode via the flexible conductor 1 and the probe 2 (i.e., via the detection probe 10), specifically, to power the first electrode E1 and the second electrode E2 via the flexible conductor 1 and the probe 2. The power supply 30 can also be used to obtain electrical information about the diode via the flexible conductor 1 and the probe 2. This electrical information can include voltage, current, and the like.

[0061] It is conceivable that, since the plurality of second electrodes E2 can be electrically connected, the power supply 30 can supply power to all the second electrodes by supplying power to one of the second electrodes.

[0062] The processing unit 40 can be used to determine whether the diode passes the test based on the electrical information and a preset threshold range. In other words, the processing unit 40 can determine whether the diode is a good product based on the electrical information and a preset threshold range.

[0063] It can be seen that the detection device 100 provided in the embodiment of the present application can realize power-on detection of the diode through the power supply 30, the processing unit 40 and the detection probe 10, which greatly reduces the damage to the electrode, improves the detection efficiency, and reduces the detection cost and loss.

[0064] In the embodiment of the present application, the power supply 30 can provide current or voltage to the diode, and the electrical information can be voltage or current. The processing unit 40 can determine whether the diode passes the test based on the following conditions:

[0065] Condition 1: The power supply 30 provides 1 mA to the first electrode E1 and the second electrode E2 (ie, the diode). The electrical information obtained by the processing unit 40 through the power supply 30 may be a voltage, and the voltage value may be greater than or equal to 2.2 V (ie, a preset voltage threshold range).

[0066] Condition 2: The power supply 30 provides 100 mA to the first electrode E1 and the second electrode E2 . The electrical information obtained by the processing unit 40 through the power supply 30 may be a voltage, and the voltage value may be less than or equal to 3 V (ie, a preset voltage threshold range).

[0067] Condition three: the power supply 30 provides -5V to the first electrode E1 and the second electrode E2. The electrical information obtained by the processing unit 40 through the power supply 30 may be current, and the current value may be less than or equal to 10uA (ie, a preset current threshold range).

[0068] If at least one of the above three conditions is met, the processing unit 40 can determine that the diode has passed the test, that is, the diode is a good product. In the embodiment of the present application, if all three conditions are met at the same time, the processing unit 40 can determine that the diode has passed the test.

[0069] Optionally, the power supply 30 may be a constant voltage source or a constant current source, etc., which is not limited in the embodiment of the present application.

[0070] Further, refer to Figure 2 The detection device 100 may further include a metal indenter 50. The metal indenter 50 may be electrically connected to the power supply 30. The flexible conductor 1 may be integrated with the metal indenter 50, or the flexible conductor 1 may be fixed to the metal indenter 50. In the embodiment of the present application, the flexible conductor 1 is fixed to the metal indenter 50 as an example.

[0071] The metal pressing head 50 can be used to support the flexible conductor 1 and apply pressure to the flexible conductor 1 so that the flexible conductor 1 is in full contact with the first electrode E1 .

[0072] It can be seen that the metal indenter 50 not only supports the flexible conductor 1 but also ensures full contact between the flexible conductor 1 and the first electrode E1, thereby improving the detection accuracy of the detection device 100. The metal indenter 50 also electrically connects the power supply 30 to the flexible conductor 1, ensuring stable power supply to the diode from the power supply 30. The metal indenter 50 is also easily replaceable, improving the practicality of the detection device 100.

[0073] Optionally, the flexible conductor 1 can be fixed on the metal pressing head 50 by a conductive material or by vulcanization. The conductive material can be a conductive adhesive, etc. Of course, the flexible conductor 1 can also be fixed by other means, which is not limited in the embodiment of the present application.

[0074] For example, the metal indenter 50 can be hard, flat, and conductive. The metal indenter 50 can be made of conductive materials such as copper and gold, and can be cylindrical, cubic, or the like. In the embodiment of the present application, to ensure that the vertical pressure exerted by the metal indenter 50 on the flexible conductor 1 is as uniform as possible when the metal indenter 50 is pressed downward, the metal indenter 50 can be a cubic shape.

[0075] It is conceivable that the flexible conductor 1 will be slightly deformed when pressure is applied by the metal pressing head 50 , and the flexible conductor 1 can overcome the slight height difference between different first electrodes to achieve contact and conduction.

[0076] In other embodiments, the diode may be a light emitting diode (micro-LED). Figure 2As shown, the detection device 100 may further include an image acquisition unit 60. The image acquisition unit 60 may be located on the light-emitting side of the light-emitting diode. The light-emitting side may be used to indicate the side of the light-emitting diode away from the flexible conductor 1.

[0077] The image acquisition unit 60 can be used to acquire image information of the light emitting diode and output it to the processing unit.

[0078] The processing unit 40 can also be used to determine whether the light emitting diode passes the test based on the electrical information, the preset threshold range and the image information. In other words, the processing unit 40 can determine whether the light emitting diode is a good product based on the electrical information, the preset threshold range and the image information.

[0079] Optionally, the image information can be Figure 3 shown. Figure 3 In the image, S1, S2, and S3 may represent defective points displayed in the image information (the diode at this location on the surface failed the test). The pixel spacing of the wafer may be 40 μm, and the diameters of the positive and negative electrodes may be 20 μm. The processing unit 40 may determine whether the LED passed the test based on the conditions described above and the number of defective points displayed in the image information.

[0080] In the embodiment of the present application, if the three conditions described above are met at the same time and the number of defective points is less than or equal to 2, the processing unit 40 can determine that the diode has passed the test. Figure 3 There are three defective points, so it can be said that the wafer W with multiple light-emitting diodes has failed the inspection.

[0081] Illustratively, in a scenario where the detection device 100 is used to detect multiple light-emitting diodes on a wafer, the stage 20 may be a transparent stage, so that the image acquisition unit 60 can acquire image information of the light-emitting diodes.

[0082] Optionally, the detection device 100 may further include a robotic arm, which may be used to fix the metal pressing head 50 so as to control the position of the flexible conductor 1 through the metal pressing head 50 , thereby realizing the detection of the diode.

[0083] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A detection probe, characterized in that: Includes Part I and Part II; At least one of the first part and the second part is a flexible conductor, and the first part and the second part are adjacently arranged. The first part is used to contact a first electrode of a diode, and the second part is used to contact a second electrode of the diode.

2. The detection probe according to claim 1, characterized in that: The flexible conductor includes a main body portion and a conductive portion; the conductive portion is mixed in the main body portion, or the conductive portion is sprayed on the surface of the main body portion.

3. The detection probe according to claim 2, characterized in that: The main body portion is rubber or silicone, and the conductor portion is conductive particles or metal paste.

4. The detection probe according to claim 3, characterized in that: The conductive particles and the metal paste both include at least one of copper, silver, or gold.

5. The detection probe according to claim 3 or 4, characterized in that: The average spacing between the conductive particles is less than or equal to 50 μm.

6. The detection probe according to any one of claims 2 to 5, characterized in that: The surface roughness of the flexible conductor is less than or equal to 20 μm; The volume resistivity of the flexible conductor is less than or equal to 0.1Ω·cm.

7. The detection probe according to any one of claims 1 to 6, characterized in that: There are a plurality of the first electrodes and a plurality of the second electrodes, the plurality of the first electrodes are arranged in a matrix form, and the plurality of the second electrodes are electrically connected.

8. The detection probe according to claim 7, characterized in that: The compressed dimension of the flexible conductor in the first direction is greater than the maximum dimension difference between any two first electrodes in the first direction.

9. A detection device, characterized in that: The device comprises a power supply, a processing unit, and a detection probe; wherein the detection probe comprises a first part and a second part; at least one of the first part and the second part is a flexible conductor, and the first part and the second part are adjacent to each other, the first part is used to contact the first electrode of the diode, and the second part is used to contact the second electrode of the diode; the processing unit and the detection probe are both electrically connected to the power supply; The power supply is used to: supply power to the diode through the detection probe, and also to obtain electrical information of the diode through the detection probe; The processing unit is configured to determine whether the diode passes the test based on the electrical information and a preset threshold range.

10. The detection device according to claim 9, characterized in that: The detection device further includes a metal pressing head, the metal pressing head is electrically connected to the power supply, the flexible conductor is integrated with the metal pressing head, or the flexible conductor is fixed to the metal pressing head; The metal pressing head is used to support the flexible conductor and apply pressure to the flexible conductor so that the flexible conductor contacts the first electrode.

11. The detection device according to claim 10, characterized in that: The flexible conductor is fixed to the metal pressing head by means of conductive material or vulcanization.

12. The detection device according to any one of claims 9 to 11, characterized in that: The diode is a light emitting diode, and the detection device further includes an image acquisition unit, which is located on the light emitting side of the light emitting diode; the light emitting side is used to indicate the side of the light emitting diode away from the flexible conductor; The image acquisition unit is used to: acquire image information of the light emitting diode and output it to the processing unit; The processing unit is further configured to determine whether the light emitting diode passes the inspection based on the electrical information, the preset threshold range, and the image information.

13. The detection device according to any one of claims 9 to 12, characterized in that: The detection device further includes a carrier; the carrier is used to carry the diode.

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