Probe card and method for inspecting light emitting elements

Abstract

A probe card and a method for inspecting light-emitting elements are disclosed. According to one aspect of this disclosure, a probe card includes: a probe substrate; a plurality of piezoelectric elements disposed on a surface of the probe substrate; and a plurality of electrode units disposed on the plurality of piezoelectric elements and including a plurality of pin electrodes, wherein each of the plurality of piezoelectric elements is configured to correspond one-to-one with each of the plurality of pin electrodes. Therefore, the Z-axis position of the plurality of pin electrodes can be changed using a plurality of piezoelectric elements having deformable shapes.

Description

Technical Field

[0001] This disclosure relates to probe cards and methods for inspecting light-emitting elements using the probe cards, and more specifically, to probe cards for inspecting light-emitting elements (LEDs) and methods for inspecting light-emitting elements using the probe cards. Background Technology

[0002] As display devices used as monitors for computers, televisions, or cellular phones, there are organic light-emitting display devices (OLEDs) that are self-emissive and liquid crystal display devices (LCDs) that require a separate light source.

[0003] The applications of display devices have diversified to personal digital assistants and monitors for computers and televisions, and research is underway on display devices with large display areas and reduced size and weight.

[0004] Furthermore, in recent years, LED-enabled display devices have garnered significant attention as the next generation of display devices. Because LEDs are formed from inorganic rather than organic materials, they offer superior reliability, resulting in a longer lifespan than liquid crystal displays or organic light-emitting diode displays. In addition, LEDs possess rapid light emission, excellent luminous efficiency, and strong shock resistance, leading to excellent stability and the ability to display high-brightness images.

[0005] The descriptions provided in the background section should not be construed as prior art simply because they are mentioned in or associated with that section. The background section may include information describing one or more aspects of the subject matter art, and the descriptions in that section do not limit this disclosure. Summary of the Invention

[0006] The purpose of this disclosure is to provide a probe card capable of inspecting the electrical characteristics of a light-emitting element and a method for inspecting the light-emitting element using the probe card.

[0007] Another objective of this disclosure is to provide a probe card and to use the probe card to inspect multiple light-emitting elements on a wafer without being limited by the flatness of the wafer.

[0008] Another object of this disclosure is to provide a probe card and a method for inspecting light-emitting elements using the probe card, the probe card being able to contact the electrodes of multiple light-emitting elements without being limited by the Z-axis positional deviation of the electrodes of the multiple light-emitting elements.

[0009] Another object of this disclosure is to provide a probe card for changing the Z-axis position of multiple pin electrodes and a method for inspecting light-emitting elements using the probe card.

[0010] Another objective of this disclosure is to provide a probe card and a method for inspecting light-emitting elements using the probe card, wherein the probe card minimizes or reduces damage to the multiple pin electrodes when the Z-axis position of the multiple pin electrodes changes.

[0011] The purpose of this disclosure is not limited to the above-mentioned purposes, and other purposes not mentioned above will be clearly understood by those skilled in the art through the following description.

[0012] According to one aspect of this disclosure, a probe card includes: a probe substrate; a plurality of piezoelectric elements disposed on a surface of the probe substrate; and a plurality of electrode units disposed on the plurality of piezoelectric elements and including a plurality of pin electrodes, each of the plurality of piezoelectric elements being configured to correspond one-to-one with each of the plurality of pin electrodes. Therefore, the Z-axis position of the plurality of pin electrodes can be changed using a plurality of piezoelectric elements having deformable shapes.

[0013] According to one aspect of this disclosure, a method for inspecting light-emitting elements includes the following steps: contacting a probe card with an array of light-emitting elements including a plurality of light-emitting elements; sensing the Z-axis position of a plurality of electrodes of the plurality of light-emitting elements; adjusting the Z-axis position of each of a plurality of pin electrodes of the probe card based on the Z-axis position; and inspecting the electrical characteristics of the plurality of light-emitting elements by contacting the plurality of pin electrodes of the probe card with the plurality of electrodes of the plurality of light-emitting elements, wherein adjusting the Z-axis position of each of the plurality of pin electrodes includes driving each of a plurality of piezoelectric elements disposed on the plurality of pin electrodes.

[0014] Further details of exemplary embodiments are included in the detailed description and accompanying drawings.

[0015] According to this disclosure, the electrical characteristics of a light-emitting element array can be examined.

[0016] According to this disclosure, the height of the pin electrodes of the probe card can be varied by taking into account the flatness of the wafer.

[0017] According to this disclosure, the height of the pin electrodes of the probe card can be changed by considering the Z-axis position of the electrodes of the light-emitting element.

[0018] According to this disclosure, the height of the pin electrodes can be changed while minimizing or reducing damage to the pin electrodes of the probe card.

[0019] The effects of this disclosure are not limited to those exemplified above, and this disclosure includes many more effects.

[0020] It should be understood that the foregoing general description and the following detailed description are exemplary and illustrative, and are intended to provide further explanation of the claimed inventive concept. Attached Figure Description

[0021] The above and other aspects, features and other advantages of this disclosure will become clearer from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0022] Figure 1 This is a diagram of an inspection system for light-emitting elements according to an exemplary embodiment of the present disclosure;

[0023] Figures 2 to 4 This is a cross-sectional view of a light-emitting element array and a probe card according to an exemplary embodiment of the present disclosure;

[0024] Figures 5A to 5F This is a process diagram illustrating a method for manufacturing a probe card according to an exemplary embodiment of the present disclosure;

[0025] Figures 6A to 6E This is a process diagram illustrating a method for manufacturing a probe card according to an exemplary embodiment of the present disclosure; and

[0026] Figure 7A and Figure 7B This is a process diagram illustrating a method for manufacturing a probe card according to an exemplary embodiment of the present disclosure. Detailed Implementation

[0027] The advantages and features of this disclosure, as well as methods for achieving these advantages and features, will become clear from the exemplary embodiments described in detail below with reference to the accompanying drawings. However, this disclosure is not limited to the exemplary embodiments disclosed herein, but will be implemented in various forms. The exemplary embodiments are provided by way of example only so that those skilled in the art can fully understand the disclosure and scope of this disclosure.

[0028] The shapes, dimensions, ratios, angles, quantities, etc., shown in the accompanying drawings used to describe exemplary embodiments of this disclosure are merely examples, and this disclosure is not limited thereto. Throughout the disclosure, the same reference numerals generally denote the same elements. Furthermore, in the following description of this disclosure, detailed explanations of known related technologies may be omitted to avoid unnecessarily obscuring the subject matter of this disclosure. Terms such as “comprising,” “having,” and “consisting of” as used herein are generally intended to allow for the addition of additional components, unless these terms are used in conjunction with the term “only.” Unless otherwise expressly stated, any reference to the singular may include the plural.

[0029] Even without explicit explanation, components are interpreted as including the normal tolerance range.

[0030] When using terms such as “above,” “over,” “below,” and “next to” to describe the positional relationship between two parts, one or more parts may be located between the two parts unless used with the terms “exactly” or “directly.”

[0031] When a component or layer is placed "on top of" another component or layer, other layers or other components can be directly inserted onto or between the other component.

[0032] Although the terms "first," "second," etc., are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from others. Therefore, in the technical concept of this disclosure, the first component mentioned below can be the second component.

[0033] Throughout the disclosure, the same reference numerals generally denote the same elements.

[0034] For ease of illustration, the dimensions and thicknesses of the components shown in the figures are illustrated, and this disclosure is not limited to the dimensions and thicknesses of the components shown.

[0035] Features of the various embodiments of this disclosure may be partially or completely adhered to or combined with each other, and may be interlocked and operated in various technical ways, and the embodiments may be performed independently or in relation to each other.

[0036] Any implementation described as an "example" in this article is not necessarily to be interpreted as preferred or superior to other implementations.

[0037] When describing temporal relationships, discontinuous cases may be included if the temporal order is described as such as “after,” “following,” “next,” and “before,” unless more restrictive terms such as “just,” “immediately,” or “directly” are used.

[0038] Furthermore, when a component or layer is “connected,” “joined,” or “adhered” to another component or layer, unless otherwise stated, the component or layer may not only be directly connected or adhered to the other component or layer, but also indirectly connected or adhered to the other component or layer, wherein one or more intermediate components or layers are “set” or “intercalated” between the components or layers. This should be understood to mean that components may be arranged to be in direct contact with each other, or may be arranged to be in direct contact with each other.

[0039] The terms “first element,” “second element,” and / or “third element” should be understood as one of the first, second, and third elements, or any or all combinations of the first, second, and third elements. For example, A, B, and / or C can refer to only A; only B; only C; any or some combinations of A, B, and C; or all of A, B, and C.

[0040] The term “at least one” should be understood to include any and all combinations of one or more of the associated listed items. For example, “at least one of the first element, the second element, and the third element” means a combination of all three listed elements, a combination of any two of the three elements, and each individual element, the first element, the second element, or the third element.

[0041] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the example embodiments pertain. It should also be understood that terms (such as those defined in common dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant field and should not be interpreted in an idealized or overly formal sense unless explicitly defined herein. For example, the terms “part” or “unit” can be applied to, for example, a single circuit or structure, an integrated circuit, a computational block of a circuit arrangement, or any structure configured to perform the functions described herein that would be understood by one of ordinary skill in the art.

[0042] In the following, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0043] Figure 1 This is a diagram of an inspection system for a light-emitting element according to an exemplary embodiment of the present disclosure.

[0044] Reference Figure 1 The inspection system 1000 is a system for inspecting the optical and electrical characteristics of the light-emitting element 120. The inspection system 1000 includes a light-emitting element array 100, a probe card 200, and an electrical measurement system 300.

[0045] The light-emitting element array 100 includes a plurality of light-emitting elements 120 disposed on a substrate. For example, the light-emitting element array 100 may be composed of a plurality of light-emitting elements 120 formed on a wafer.

[0046] The probe card 200 is an inspection device for inspecting multiple light-emitting elements 120. The probe card 200 can apply a signal to each of the multiple light-emitting elements 120 in the light-emitting element array 100 and detect the signals output from the multiple light-emitting elements 120. The probe card 200 connects pin electrodes to the multiple light-emitting elements 120 to inspect their electrical characteristics.

[0047] The electrical measurement system 300 applies a drive signal to the probe card 200 and determines defects in the light-emitting element 120 based on information measured by the probe card 200. The electrical measurement system 300 is connected to the probe card 200 to examine the electrical characteristics of the light-emitting element 120. For example, the electrical measurement system 300 applies a voltage to the pin electrodes of the probe card 200 or receives information from the light-emitting element 120 measured by the probe card 200 to analyze the characteristics of the light-emitting element 120. The electrical measurement system 300 identifies electrical characteristics of the light-emitting element 120 (e.g., responsiveness or leakage current) to determine short-circuit or open-circuit faults in the light-emitting element 120.

[0048] The electrical measurement system 300 may include various configurations for driving the probe card 200. For example, the electrical measurement system 300 may include a relay board 320, a flexible printed circuit 310, a 3D displacement sensor 340, and a source meter 330. The relay board 320 outputs signals to or receives signals output from the probe card 200 to examine the characteristics of the light-emitting element 120. The flexible printed circuit 310 can transmit signals between the probe card 200 and the relay board 320. The 3D displacement sensor 340 can sense the Z-axis position of the first electrode 124 and the second electrode 125 of the light-emitting element 120. The source meter 330 can generate a voltage to be applied to the electrode unit 230 of the probe card 200. Furthermore, the source meter 330 can generate a voltage to be applied to the piezoelectric element 220 of the probe card 200 based on the sensing results of the 3D displacement sensor 340.

[0049] The following is for reference Figures 2 to 4 The light-emitting element array 100 and the probe card 200 are described in detail.

[0050] Figures 2 to 4 This is a cross-sectional view of a light-emitting element array and a probe card according to an exemplary embodiment of this disclosure. Figures 2 to 4 For ease of explanation, only one of the multiple light-emitting elements 120 of the light-emitting element array 100 is shown.

[0051] Reference Figures 2 to 4 The light-emitting element array 100 includes an array substrate 110 and a plurality of light-emitting elements 120.

[0052] A plurality of light-emitting elements 120 are disposed on the array substrate 110. The array substrate 110 may be a wafer on which the light-emitting elements 120 are grown. After the inspection process is completed, the plurality of light-emitting elements 120 on the array substrate 110 are transferred to other locations for use.

[0053] Multiple light-emitting elements 120 are disposed on the array substrate 110. The multiple light-emitting elements 120 are semiconductor elements that emit light in an array manner by means of current. The light-emitting elements 120 can be either light-emitting diodes (LEDs) or micro light-emitting diodes (micro LEDs), but the exemplary embodiments of this disclosure are not limited thereto.

[0054] Each of the plurality of light-emitting elements 120 includes a first semiconductor layer 121, a light-emitting layer 122, a second semiconductor layer 123, a first electrode 124, a second electrode 125, and a protective film 126.

[0055] A first semiconductor layer 121 is disposed on the array substrate 110, and a second semiconductor layer 123 is disposed on the first semiconductor layer 121. Either the first semiconductor layer 121 or the second semiconductor layer 123 can be a semiconductor layer doped with n-type impurities, while the other can be a semiconductor layer doped with p-type impurities. For example, the first semiconductor layer 121 and the second semiconductor layer 123 can be semiconductor layers doped with n-type or p-type impurities in materials such as gallium nitride (GaN), indium aluminum phosphide (InAlP), or gallium arsenide (GaAs).

[0056] A light-emitting layer 122 is disposed between a first semiconductor layer 121 and a second semiconductor layer 123. The light-emitting layer 122 can emit light based on a driving current supplied to the light-emitting element 120. For example, the light-emitting layer 122 can be formed of a single-layer or multiple quantum well (MQW) structure, and can be formed of, for example, indium gallium nitride (InGaN) or gallium nitride (GaN), but is not limited thereto.

[0057] A first electrode 124 is disposed on the top surface of the first semiconductor layer 121, and a second electrode 125 is disposed on the top surface of the second semiconductor layer 123. Voltages are applied to the first electrode 124 and the second electrode 125 respectively to drive the light-emitting element 120.

[0058] The protective film 126 is disposed around the first semiconductor layer 121, the light-emitting layer 122, and the second semiconductor layer 123. The protective film 126 is an insulating film disposed around at least a portion of the first semiconductor layer 121, the light-emitting layer 122, and the second semiconductor layer 123 to suppress short-circuit defects.

[0059] The probe card 200 is an inspection device for inspecting multiple light-emitting elements 120. The probe card 200 includes a probe substrate 210, a first insulating layer 211, a second insulating layer 212, a third insulating layer 213, an elastic layer 214, multiple piezoelectric elements 220, and multiple electrode units 230.

[0060] First, the probe substrate 210 is a component that supports the other structures of the probe card 200. Multiple piezoelectric elements 220 and multiple electrode units 230 are formed on the probe substrate 210 to form the probe card 200. The probe substrate 210 can be disposed in the region between the multiple piezoelectric elements 220.

[0061] Multiple piezoelectric elements 220 are disposed on one surface of the probe substrate 210. The multiple piezoelectric elements 220 are a structure for controlling the height of the lead electrodes. In the probe card 200 according to an exemplary embodiment of the present disclosure, the height of the multiple lead electrodes can be adjusted using the converse piezoelectric effect of the multiple piezoelectric elements 220.

[0062] According to the inverse piezoelectric effect, when a voltage is applied to the piezoelectric element 220, stress is generated in the piezoelectric element 220, that is, the piezoelectric element 220 contracts or expands and vibrates. Therefore, applying a voltage to the piezoelectric element 220 causes it to expand or contract, thereby controlling the height of the lead electrode below the piezoelectric element 220. For example, as... Figure 4 As shown, when the piezoelectric element 220 expands to bulge downwards, pressure can be applied to the vibrating diaphragm 224 and fluid 240 below the piezoelectric element 220, and the multiple lead electrodes can also be affected, allowing the ends of the lead electrodes to descend. If in such... Figure 4 In the state shown, when the piezoelectric element 220 contracts again, the pressure applied to the vibrating diaphragm 224 and the fluid 240 below the piezoelectric element 220 can be reduced, and the ends of the pin electrodes can rise. Therefore, by adjusting the voltage applied to the piezoelectric element 220, the height of the multiple pin electrodes can be controlled, thereby deforming the shape of the piezoelectric element 220.

[0063] Each of the plurality of piezoelectric elements 220 includes a first driving electrode 221, a piezoelectric layer 222, a second driving electrode 223, and a vibrating diaphragm 224.

[0064] First, a first driving electrode 221 is disposed on one surface of the piezoelectric layer 222, and a second driving electrode 223 is disposed on the opposite surface of the piezoelectric layer 222. That is, the first driving electrode 221 and the second driving electrode 223 can be disposed on both surfaces of the piezoelectric layer 222. The first driving electrode 221 and the second driving electrode 223 are electrodes for applying voltage to the piezoelectric layer 222.

[0065] Simultaneously, the first driving electrode 221 can apply different voltages to the plurality of piezoelectric layers 222, and the second driving electrode 223 can apply a common voltage to the plurality of piezoelectric layers 222. Therefore, the first driving electrode 221 can be formed in each of the plurality of piezoelectric layers 222 respectively, and the second driving electrode 223 can be formed together in the plurality of piezoelectric layers 222. However, the plurality of second driving electrodes 223 can be formed corresponding to the plurality of piezoelectric layers 222, but are not limited thereto.

[0066] When an electric field is applied to the piezoelectric layer 222, stress is generated; conversely, when stress is applied to the piezoelectric layer 222, an electric field is generated. Therefore, when a voltage is applied to the piezoelectric layer 222 from the first driving electrode 221 and the second driving electrode 223, the piezoelectric layer 222 may deform. For example, the piezoelectric layer 222 may be formed of a PZT-type piezoelectric ceramic material composed of a solid solution of zirconate (PbZrO3) and titanate (PbTiO3).

[0067] The piezoelectric element 220 can be exposed from the probe substrate 210. For example, the probe substrate 210 can be disposed in the region between the plurality of piezoelectric elements 220, and the first driving electrode 221 of the piezoelectric element 220 can be exposed from the probe substrate 210. Therefore, the portion of the probe substrate 210 covering the piezoelectric element 220 is removed, such that interference between the probe substrate 210 and the piezoelectric element 220 can be minimized or reduced when the piezoelectric element 220 is deformed, and the piezoelectric element 220 can be deformed more easily.

[0068] Next, a first insulating layer 211 is disposed on one surface of the probe card 200 and is configured to surround the side surfaces of the first driving electrode 221 and the piezoelectric layer 222 of the piezoelectric element 220. The first insulating layer 211 may be disposed in the remaining areas of the piezoelectric element 220 where the first driving electrode 221 and the piezoelectric layer 222 are not disposed. For example, the first insulating layer 211 is disposed between the second driving electrode 223 and the probe substrate 210, and may be configured to surround the first driving electrodes 221 and the piezoelectric layer 222 of multiple piezoelectric elements 220.

[0069] A plurality of vibrating membranes 224 are disposed on one surface of the second driving electrode 223. Each of the plurality of vibrating membranes 224 can be configured to correspond to each of the plurality of piezoelectric layers 222. The plurality of vibrating membranes 224 can be disposed spaced apart from each other. For example, a gap 224O can be formed between a vibrating membrane 224 overlapping one piezoelectric layer 222 and a vibrating membrane 224 overlapping another piezoelectric layer 222. The gap 224O can be disposed along the periphery of the vibrating membranes 224 and the periphery of the first driving electrode 221. Therefore, when one vibrating membrane 224 deforms, the adjacent vibrating membrane 224 may remain unaffected.

[0070] Next, a second insulating layer 212 is provided on one surface of the plurality of diaphragms 224. The second insulating layer 212 may be configured to cover all one surface of the plurality of diaphragms 224 and the gap 224O between the plurality of diaphragms 224.

[0071] Multiple electrode units 230 are disposed on one surface of the second insulating layer 212. The multiple electrode units 230 are configured to inspect the light-emitting element 120, and defects in the light-emitting element 120 can be inspected by applying a voltage to each of the first electrode 124 and the second electrode 125 of the light-emitting element 120. Each of the multiple electrode units 230 includes a first lead electrode 231, a second lead electrode 232, a first wiring 233, and a second wiring 234.

[0072] First, a first wiring 233 and a second wiring 234 are formed on one surface of the second insulating layer 212. The first wiring 233 is connected to a first pin electrode 231, and the second wiring 234 is connected to a second pin electrode 232. The first wiring 233 and the second wiring 234 are connected to the electrical measurement system 300 to transmit voltage to the first pin electrode 231 and the second pin electrode 232. For example, the first wiring 233 and the second wiring 234 extend toward the side surface of the probe card 200 to electrically connect to a flexible printed circuit 310 bonded to the side surface of the probe card 200 to exchange signals with the electrical measurement system 300.

[0073] The first wiring 233 and the second wiring 234 can be formed by first portions 233a and 234a, second portions 233b and 234b, and third portions 233c and 234c. The first portions 233a and 234a of the first wiring 233 and the second wiring 234 are disposed on one surface of the second insulating layer 212. The second portions 233b and 234b of the first wiring 233 and the second wiring 234 can pass through the third insulating layer 213, and the two ends of the second portions 233b and 234b can be connected to the first portions 233a and 234a and the third portions 233c and 234c. The third portions 233c and 234c of the first wiring 233 and the second wiring 234 are disposed on one surface of the third insulating layer 213 and can be connected to the second portions 233b and 234b, the first pin electrode 231, and the second pin electrode 232.

[0074] The first pin electrode 231 and the second pin electrode 232 are electrodes for applying voltage to the plurality of light-emitting elements 120. When the probe card 200 contacts the light-emitting element array 100, the first pin electrode 231 can contact the first electrode 124 of the light-emitting element 120, and the second pin electrode 232 can contact the second electrode 125 of the light-emitting element 120. Therefore, voltage is applied to each of the first electrode 124 and the second electrode 125 of the light-emitting element 120 using the first pin electrode 231 and the second pin electrode 232 to inspect the light-emitting element 120.

[0075] A first pin electrode 231 is disposed on a first wiring 233, and a second pin electrode 232 is disposed on a second wiring 234. The first pin electrode 231 can be connected to a third portion (233c, 234c) of the first wiring 233, and the second pin electrode 232 can be connected to a third portion (233c, 234c) of the second wiring 234. The first pin electrode 231 and the second pin electrode 232 can be configured to protrude beyond the elastic layer 214. In this case, considering the height of the first electrode 124 and the second electrode 125 of the light-emitting element 120, the lengths of the first pin electrode 231 and the second pin electrode 232 can be set to be different from each other. For example, when the top surface of the first electrode 124 is lower than the top surface of the second electrode 125, the length of the first pin electrode 231 in contact with the first electrode 124 can be formed to be longer than the length of the second pin electrode 232 in contact with the second electrode 125.

[0076] Next, a third insulating layer 213 is disposed on one surface of the second insulating layer 212. The third insulating layer 213 may be disposed on one surface of the second insulating layer 212 to cover the first portions 233a and 234a and the second portions 233b and 234b of the first wiring 233 and the second wiring 234. At this time, the third insulating layer 213 may include a plurality of openings overlapping with the plurality of piezoelectric layers 222.

[0077] Fluid 240 is disposed in a plurality of openings in the third insulating layer 213. Fluid 240 may be formed from any of a gaseous or liquid material, such as air or oil. Fluid 240 fills the openings in the third insulating layer 213 to transmit pressure from the deformable piezoelectric element 220 to the first lead electrode 231 and the second lead electrode 232.

[0078] For example, such as Figure 4As shown, when the diaphragm 224 and the second insulating layer 212 deform into a downward bulge due to pressure from the piezoelectric element 220, the fluid 240 is also affected by the pressure from the piezoelectric element 220, the diaphragm 224, and the second insulating layer 212, pressing the first lead electrode 231, the second lead electrode 232, and the third portions 233c and 234c. Pressure can be uniformly transmitted through the fluid 240 to all the first lead electrodes 231, the second lead electrodes 232, and the third portions 233c and 234c. Therefore, the fluid 240 is positioned between the diaphragm 224 and the electrode unit 230 to suppress physical contact between the diaphragm 224 and the electrode unit 230, and to minimize or reduce damage to the electrode unit 230 associated with physical contact between the diaphragm 224 and the electrode unit 230.

[0079] The elastic layer 214 is disposed in a manner that covers the electrode unit 230 and the fluid 240. The elastic layer 214 may be disposed to cover all one surface of the third insulating layer 213, the first wiring 233, the second wiring 234, and the fluid 240, and the first lead electrode 231 and the second lead electrode 232 are connected to the first wiring 233 and the second wiring 234 passing through the elastic layer 214. The elastic layer 214 is disposed around at least a portion of the first lead electrode 231 and the second lead electrode 232 to disperse the forces applied to the first lead electrode 231 and the second lead electrode 232 and reduce damage to the first lead electrode 231 and the second lead electrode 232.

[0080] Meanwhile, the array substrate 110 can be a wafer on which the light-emitting elements 120 are grown, and a sapphire substrate can be used as the wafer. An epitaxial layer is grown on the wafer to form a plurality of light-emitting elements 120. At this time, there is a difference in the coefficient of thermal expansion between the wafer and the epitaxial layer formed on the wafer, which may generate tensile stress and the wafer may bend.

[0081] Reference Figure 4 When the wafer is bent, the heights of the first electrode 124 and the second electrode 125 of each of the plurality of light-emitting elements 120 disposed on the wafer can be different. For example, when the wafer has an inclined surface and a horizontal surface, the angle of the light-emitting element 120 disposed on the inclined surface is different from the angle of the light-emitting element 120 disposed on the horizontal surface, so that the heights of the first electrode 124 and the second electrode 125 can also be different.

[0082] Therefore, in the probe card 200 according to an exemplary embodiment of this disclosure, the heights of the first pin electrode 231 and the second pin electrode 232, i.e., the Z-axis positions, can vary, taking into account the Z-axis positions of the first electrode 124 and the second electrode 125 of the light-emitting element 120. The electrical measurement system 300 can use a 3D displacement sensor 340 to sense the Z-axis positions of the first electrode 124 and the second electrode 125 of the light-emitting element 120. The electrical measurement system 300 can calculate the displacement change of the Z-axis positions of the first pin electrode 231 and the second pin electrode 232 by reflecting the Z-axis positions of the first electrode 124 and the second electrode 125. The electrical measurement system 300 applies a voltage based on the displacement change to the first driving electrode 221 and the second driving electrode 223 of the piezoelectric element 220 to deform the piezoelectric element 220. Therefore, the heights of the first pin electrode 231 and the second pin electrode 232 can be controlled respectively according to the deformation of the piezoelectric element 220. Therefore, in the probe card 200 according to an exemplary embodiment of the present disclosure, the heights of the first pin electrode 231 and the second pin electrode 232 can be varied to easily inspect a plurality of light-emitting elements 120 without being limited by the Z-axis positional deviation of the first electrode 124 and the second electrode 125 of the light-emitting elements 120.

[0083] Meanwhile, for ease of description, only one light-emitting element 120, one piezoelectric element 220, and one electrode unit 230 are shown in the accompanying drawings. However, multiple light-emitting elements 120 are disposed on the array substrate 110, and multiple piezoelectric elements 220 and multiple electrode units 230 corresponding to the multiple light-emitting elements 120 can be disposed in the probe card 200. Therefore, multiple light-emitting elements 120 can be inspected simultaneously using the probe card 200 including multiple piezoelectric elements 220 and multiple electrode units 230.

[0084] In the following text, reference will be made to Figures 5A to 7B A method for manufacturing a probe card 200 according to an exemplary embodiment of the present disclosure is described.

[0085] Figures 5A to 5F This is a process diagram illustrating a method for manufacturing a probe card according to an exemplary embodiment of the present disclosure. Figures 6A to 6E This is a process diagram illustrating a method for manufacturing a probe card according to an exemplary embodiment of the present disclosure. Figure 7A and Figure 7B This is a process diagram illustrating a method for manufacturing a probe card according to an exemplary embodiment of the present disclosure. Specifically, Figures 5A to 5E This is a cross-sectional view used to illustrate the manufacturing method of electrode unit 230. Figure 5F This is a plan view illustrating the manufacturing method of electrode unit 230. Figures 6A to 6D This is a cross-sectional view used to illustrate the manufacturing method of the piezoelectric element 220. Figure 6EThis is a plan view used to illustrate the manufacturing method of the piezoelectric element 220. Figure 7A and Figure 7B This is a cross-sectional view illustrating the method of fabricating the first lead electrode 231 and the second lead electrode 232 by joining the electrode unit 230 and the piezoelectric element 220. For ease of explanation, in... Figure 5F The second insulating layer 212 is not shown in the diagram.

[0086] Reference Figures 5A to 5F Multiple electrode units 230 are formed on the first temporary substrate TS1.

[0087] First, refer to Figure 5A An elastic layer 214 is formed on a first temporary substrate TS1, and third portions 233c and 234c of the first wiring 233 and the second wiring 234 are formed on the elastic layer 214. The first temporary substrate TS1 is temporarily used for the manufacturing process of the electrode unit 230 and can be removed in a subsequent process. The thickness of the elastic layer 214 is formed to be greater than the thickness of the final structure of the probe card 200, and can be processed to be thinner after the formation of the first pin electrode 231 and the second pin electrode 232 is completed.

[0088] Reference Figure 5B A third insulating layer 213 is formed on the third portions 233c and 234c of the first wiring 233 and the second wiring 234. At this time, a portion of the third insulating layer 213 covering the third portions 233c and 234c is removed to form a plurality of openings, thereby allowing fluid 240 to fill the third portions 233c and 234c of the first wiring 233 and the second wiring 234.

[0089] Reference Figure 5C This forms second portions 233b and 234b of the first wiring 233 and the second wiring 234. The second portions 233b and 234b can be formed to pass through the third insulating layer 213. The second portions 233b and 234b can be connected to the third portions 233c and 234c while passing through the third insulating layer 213.

[0090] refer to Figure 5D First portions 233a and 234a of the first wiring 233 and the second wiring 234 are formed and filled with fluid 240. The first portions 233a and 234a can be formed on the surface of the third insulating layer 213 and can be connected to the second portions 233b and 234b. Therefore, the formation process of the first wiring 233 and the second wiring 234 formed by the first portions 233a and 234a, the second portions 233b and 234b, and the third portions 233c and 234c can be completed. Fluid 240 can fill each of the plurality of openings in the third insulating layer 213.

[0091] refer to Figure 5E A second insulating layer 212 is formed on the third insulating layer 213. The second insulating layer 212 is configured to cover the entire first wiring 233, the second wiring 234 and the fluid 240 to protect the first wiring 233, the second wiring 234 and the fluid 240.

[0092] Reference Figure 5F The first wiring 233 and the second wiring 234 are connected to the electrical measurement system 300. For example, first portions 233a and 234a of the first wiring 233 and the second wiring 234 may extend toward the side surface of the probe card 200. The flexible printed circuit 310 of the electrical measurement system 300 is bonded to the side surface of the probe card 200 to connect the flexible printed circuit 310 of the electrical measurement system 300 to the first wiring 233 and the second wiring 234. Therefore, the first wiring 233 and the second wiring 234 can receive signals from the relay substrate 320 and the source meter 330 through the flexible printed circuit 310 and send the signals to the first pin electrode 231 and the second pin electrode 232.

[0093] Next, refer to Figures 6A to 6E Multiple piezoelectric elements 220 are formed on the second temporary substrate TS2.

[0094] First, refer to Figure 6A A second driving electrode 223 is formed on the second temporary substrate TS2. At this time, the second driving electrode 223 of each of the plurality of piezoelectric elements 220 applies the same common voltage to the piezoelectric layer 222, so that a second driving electrode 223 can be formed in the plurality of piezoelectric elements 220.

[0095] Reference Figure 6B Multiple piezoelectric layers 222 and multiple first driving electrodes 221 are formed on the second driving electrode 223. The multiple piezoelectric layers 222 can be formed on the second driving electrode 223, and the first driving electrodes 221 can be formed on top of each of the multiple piezoelectric layers 222.

[0096] Reference Figure 6C A first insulating layer 211 is formed around a plurality of piezoelectric layers 222 and a plurality of first driving electrodes 221. The first insulating layer 211 may be formed to cover the second driving electrode 223. The first insulating layer 211 may surround the side surfaces of each of the plurality of piezoelectric layers 222 and the plurality of first driving electrodes 221. The top surfaces of the plurality of first driving electrodes 221 may be exposed from the first insulating layer 211.

[0097] Next, a probe substrate 210 is formed on the first insulating layer 211. The probe substrate 210 may be disposed only partially in the region between the plurality of piezoelectric layers 222.

[0098] Reference Figure 6D A plurality of vibrating films 224 are formed from a second temporary substrate TS2. A portion of the second temporary substrate TS2 corresponding to the region between the plurality of piezoelectric layers 222 is removed to form a plurality of vibrating films 224 corresponding one-to-one with the plurality of piezoelectric layers 222. Furthermore, for the purpose of flexible deformation of the vibrating films 224, the thickness of the second temporary substrate TS2, i.e., the thickness of the vibrating films 224, can be processed to be thinner.

[0099] refer to Figure 6E Multiple piezoelectric elements 220 are connected to the electrical measurement system 300. For example, a first driving electrode 221 is configured to extend toward a side surface of the probe card 200, and a flexible printed circuit 310 of the electrical measurement system 300 is coupled to a side surface of the probe card 200 to connect the first driving electrode 221 and the electrical measurement system 300.

[0100] Connecting lines 220L extending from each of the plurality of second driving electrodes 223 may be disposed on the first insulating layer 211. The connecting lines 220L may extend toward the other side surface of the probe card 200 and may be connected to a flexible printed circuit 310 bonded to the other side surface of the probe card 200.

[0101] Therefore, the first driving electrode 221 and the second driving electrode 223 of each of the plurality of piezoelectric elements 220 can be driven by signals applied from the relay board 320 and the source table 330 via the flexible printed circuit 310. At this time, the signals applied to the first driving electrode 221 and the second driving electrode 223 can vary according to the Z-axis position of the first electrode 124 and the second electrode 125 of the light-emitting element 120 sensed by the 3D displacement sensor 340.

[0102] Next, refer to Figure 7A Multiple electrode units 230 and multiple piezoelectric elements 220 are joined together, and the first temporary substrate TS1 is removed. For example, the multiple electrode units 230 and multiple piezoelectric elements 220 may be joined together to place multiple vibrating membranes 224 on a second insulating layer 212 covering the multiple electrode units 230. Then, the first temporary substrate TS1 is removed to expose the elastic layer 214.

[0103] Reference Figure 7B A first lead electrode 231 and a second lead electrode 232 are formed. A hole is formed in the elastic layer 214 overlapping with the first portions 233a and 234a of the first wiring 233 and the second wiring 234, and an electroplating process is performed in this hole to form the first lead electrode 231 and the second lead electrode 232. Therefore, the first lead electrode 231 and the second lead electrode 232 can be formed connected to the first wiring 233 and the second wiring 234.

[0104] Finally, the elastic layer 214 is processed to be thin so that the first pin electrode 231 and the second pin electrode 232 are exposed from the elastic layer 214.

[0105] Therefore, in the probe card 200 according to an exemplary embodiment of the present disclosure, a plurality of piezoelectric elements 220 are bonded to a plurality of electrode units 230 to manufacture a probe card 200 including a first pin electrode 231 and a second pin electrode 232 having variable heights. For example, a first wiring 233 and a second wiring 234 of the electrode units 230 and a fluid 240 may be formed on a first temporary substrate TS1, and a plurality of piezoelectric elements 220 may be formed on a second temporary substrate TS2. After forming a plurality of vibrating membranes 224 by patterning the second temporary substrate TS2, the plurality of vibrating membranes 224 and the plurality of piezoelectric elements 220 may be bonded to the first wiring 233 and the second wiring 234. Finally, the first temporary substrate TS1 is removed, and the holes of the elastic layer 214 are electroplated to form the first pin electrode 231 and the second pin electrode 232, thereby manufacturing a probe card 200 including both the electrode units 230 and the piezoelectric elements 220. Therefore, a probe card 200 can be formed that can easily contact the first electrode 124 and the second electrode 125 of the multiple light-emitting elements 120 without being limited by the flatness of the array substrate 110, and the inspection accuracy of the multiple light-emitting elements 120 can be improved.

[0106] Exemplary embodiments of this disclosure can also be described as follows:

[0107] According to one aspect of this disclosure, a probe card includes a probe substrate, a plurality of piezoelectric elements disposed on a surface of the probe substrate, and a plurality of electrode units disposed on the plurality of piezoelectric elements and having a plurality of pin electrodes, wherein each of the plurality of piezoelectric elements is configured to correspond one-to-one with each of the plurality of pin electrodes.

[0108] Each of the plurality of electrode units may further include a first wiring connected to a first pin electrode among the plurality of pin electrodes and a second wiring connected to a second pin electrode among the plurality of pin electrodes, and each of the first pin electrode and the second pin electrode may overlap with different piezoelectric elements among the plurality of piezoelectric elements.

[0109] Each of the plurality of piezoelectric elements may include a first driving electrode located on a surface of a probe substrate, a piezoelectric layer located on the first driving electrode, a second driving electrode located on the piezoelectric layer, and a vibrating diaphragm located on the second driving electrode.

[0110] The probe substrate and the first driving electrode can be arranged spaced apart from each other.

[0111] The probe card may further include: a first insulating layer located between the probe substrate and the second driving electrode; a second insulating layer disposed between the diaphragm and the first wiring and between the diaphragm and the second wiring; a third insulating layer disposed on one surface of the second insulating layer and surrounding the first wiring and the second wiring; and an elastic layer disposed on one surface of the third insulating layer and surrounding the first pin electrode and the second pin electrode.

[0112] Each of the first wiring and the second wiring may include a first portion disposed between the second insulating layer and the third insulating layer, a second portion passing through the third insulating layer and connected to the first portion, and a third portion disposed on a surface of the third insulating layer and connecting the second portion and the first pin electrode and the second pin electrode.

[0113] The third insulating layer may include an opening that overlaps with the piezoelectric layer of the plurality of piezoelectric elements and exposes at least a portion of the third portion, and may also contain fluid filling the opening.

[0114] The piezoelectric layer of each of the plurality of piezoelectric elements can be configured to deform into a convex shape toward the vibrating diaphragm and electrode unit by voltage of the first driving electrode and the second driving electrode, and the vibrating diaphragm, the second insulating layer and the fluid are configured to deform along the convex shape of the piezoelectric layer.

[0115] The end of each of the multiple pin electrodes can be configured to rise or fall by deformation of the piezoelectric layer, the vibrating diaphragm, the second insulating layer, and the fluid.

[0116] According to one aspect of this disclosure, a method for inspecting light-emitting elements includes the following steps: contacting a probe card with an array of light-emitting elements including a plurality of light-emitting elements; sensing the Z-axis position of a plurality of electrodes of the plurality of light-emitting elements; adjusting the Z-axis position of each of a plurality of pin electrodes of the probe card based on the Z-axis position; and inspecting the electrical characteristics of the plurality of light-emitting elements by contacting the plurality of pin electrodes of the probe card with the plurality of electrodes of the plurality of light-emitting elements, wherein the step of adjusting the Z-axis position of each of the plurality of pin electrodes includes driving each of a plurality of piezoelectric elements disposed on the plurality of pin electrodes.

[0117] Each of the plurality of piezoelectric elements may include a vibrating diaphragm disposed above each of the plurality of pin electrodes, a second driving electrode disposed on the vibrating diaphragm, a piezoelectric layer disposed on the second driving electrode, and a first driving electrode disposed on the piezoelectric layer, and the piezoelectric layer of each of the plurality of piezoelectric elements may overlap with each of the plurality of pin electrodes.

[0118] When each of the plurality of piezoelectric elements is driven, the shape of each of the plurality of piezoelectric elements can be deformed by the applied voltage, and each of the plurality of piezoelectric elements can be configured to apply pressure to the plurality of pin electrodes.

[0119] Alternatively, the probe card may have an elastic layer surrounding a portion of a plurality of pin electrodes, and a fluid disposed between the diaphragm and the elastic layer and overlapping each of the plurality of pin electrodes, wherein, in the driving of each of the plurality of piezoelectric elements, the shape of each of the plurality of piezoelectric elements is deformed by the applied voltage, and each of the plurality of piezoelectric elements may be configured to apply pressure to the elastic layer, the fluid and the plurality of pin electrodes.

[0120] Although exemplary embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, the present disclosure is not limited thereto and may be implemented in many different forms without departing from the technical concept of the present disclosure. Therefore, the exemplary embodiments of the present disclosure are provided for illustrative purposes only and are not intended to limit the technical concept of the present disclosure. The scope of the technical concept of the present disclosure is not limited thereto. Therefore, it should be understood that the above exemplary embodiments are illustrative in all respects and do not limit the present disclosure. All technical concepts within the equivalent scope of the present disclosure should be construed as falling within the scope of the present disclosure.

[0121] Cross-references to related applications

[0122] This application claims priority to Korean Patent Application No. 10-2024-0198291, filed on December 27, 2024, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

Claims

1. A probe card, the probe card comprising: Probe substrate; A plurality of piezoelectric elements are disposed on one surface of the probe substrate; as well as Multiple electrode units, wherein the multiple electrode units are disposed on the multiple piezoelectric elements and include multiple pin electrodes, Each of the plurality of piezoelectric elements is configured to correspond one-to-one with each of the plurality of pin electrodes.

2. The probe card according to claim 1, wherein, Each of the plurality of electrode units further includes: A first wiring, the first wiring being connected to a first pin electrode among the plurality of pin electrodes; and The second wiring, the second wiring being connected to the second pin electrode among the plurality of pin electrodes, and Each of the first pin electrode and the second pin electrode overlaps with a different piezoelectric element among the plurality of piezoelectric elements.

3. The probe card according to claim 2, wherein, Each of the plurality of piezoelectric elements includes: A first driving electrode is located on one surface of the probe substrate. A piezoelectric layer is located on the first driving electrode; The second driving electrode is located on the piezoelectric layer; A vibrating diaphragm is located on the second driving electrode.

4. The probe card according to claim 3, wherein, The probe substrate and the first driving electrode are spaced apart from each other.

5. The probe card according to claim 3, further comprising: A first insulating layer is provided between the probe substrate and the second driving electrode. A second insulating layer is disposed between the vibrating diaphragm and the first wiring and between the vibrating diaphragm and the second wiring. A third insulating layer is disposed on one surface of the second insulating layer and surrounds the first wiring and the second wiring; An elastic layer is disposed on one surface of the third insulating layer and surrounds the first pin electrode and the second pin electrode.

6. The probe card according to claim 5, wherein, Each of the first wiring and the second wiring includes: The first part is disposed between the second insulating layer and the third insulating layer; The second part, which passes through the third insulating layer and is connected to the first part; and The third part is disposed on one surface of the third insulating layer, and Wherein, the third portion of the first wiring is connected to the second portion of the first wiring and the first pin electrode, and the third portion of the second wiring is connected to the second portion of the second wiring and the second pin electrode.

7. The probe card according to claim 6, wherein, The third insulating layer includes an opening that overlaps with the piezoelectric layers of the plurality of piezoelectric elements and exposes at least a portion of the third portion. Fluid is provided to fill the opening.

8. The probe card according to claim 7, wherein, The piezoelectric layer of each of the plurality of piezoelectric elements is configured to deform into a convex shape toward the vibrating diaphragm and the electrode unit by voltage from the first driving electrode and the second driving electrode, and the vibrating diaphragm, the second insulating layer and the fluid are configured to deform along the convex shape of the piezoelectric layer.

9. The probe card according to claim 8, wherein, The end of each of the plurality of pin electrodes is configured to rise or fall due to the deformation of the piezoelectric layer, the vibrating diaphragm, the second insulating layer, and the fluid.

10. A method for inspecting a light-emitting element, the method comprising the following steps: Make the probe card contact the array of light-emitting elements, which includes multiple light-emitting elements; Sensing the Z-axis position of multiple electrodes of the multiple light-emitting elements; The Z-axis position of each of the multiple pin electrodes of the probe card is adjusted based on the Z-axis position. as well as The electrical characteristics of the plurality of light-emitting elements are examined by contacting the plurality of pin electrodes of the probe card with the plurality of electrodes of the plurality of light-emitting elements. The step of adjusting the Z-axis position of each of the plurality of pin electrodes includes the following steps: Each of the plurality of piezoelectric elements disposed on the plurality of pin electrodes is driven.

11. The method for inspecting a light-emitting element according to claim 10, wherein, Each of the plurality of piezoelectric elements includes: A diaphragm, wherein the diaphragm is disposed above each of the plurality of pin electrodes; The second driving electrode is disposed on the vibrating diaphragm; A piezoelectric layer, wherein the piezoelectric layer is disposed on the second driving electrode; and A first driving electrode is disposed on the piezoelectric layer, and In this embodiment, the piezoelectric layer of each of the plurality of piezoelectric elements overlaps with each of the plurality of pin electrodes.

12. The method for inspecting a light-emitting element according to claim 11, wherein, In the driving of each of the plurality of piezoelectric elements, the shape of each of the plurality of piezoelectric elements is deformed by the applied voltage, and each of the plurality of piezoelectric elements is configured to apply pressure to the plurality of pin electrodes.

13. The method for inspecting a light-emitting element according to claim 11, wherein, The probe card includes: An elastic layer, the elastic layer surrounding a portion of the plurality of pin electrodes; and A fluid, disposed between the diaphragm and the elastic layer and overlapping with each of the plurality of pin electrodes, and In the driving of each of the plurality of piezoelectric elements, the shape of each of the plurality of piezoelectric elements is deformed by the applied voltage, and each of the plurality of piezoelectric elements is configured to apply pressure to the elastic layer, the fluid and the plurality of pin electrodes.

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