Method of producing an optoelectronic component and optoelectronic component

Abstract

A method for producing an optoelectronic component (10) comprises the following method steps. A first foil (2) is provided, which comprises a top side (3) and a bottom side (4), wherein at least one optoelectronic semiconductor chip (5) designed to emit electromagnetic radiation is arranged on the top side (3) of the first foil (2). An at least partially cured encapsulation film (9) is arranged on the top side (3) of the first foil (2), wherein the optoelectronic semiconductor chip (5) is embedded in the encapsulation film (9).

Description

[0001] manual

[0002] This invention relates to a method for manufacturing optoelectronic components and to optoelectronic components themselves.

[0003] This patent application claims priority to German Patent Application 10 2024 105 961.3, the disclosure of which is incorporated herein by reference.

[0004] According to existing technology, optoelectronic components including light-emitting diodes (LEDs) arranged on foil are known. To date, only very specific materials such as, for example, polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), or Sentry glass are suitable for foil encapsulation. However, these materials have drawbacks in terms of robustness and compatibility with customer systems.

[0005] The object of this invention is to describe in detail an improved method for manufacturing optoelectronic components and to provide improved optoelectronic components. This object is achieved by a method for manufacturing optoelectronic components and optoelectronic components, each having the features of the independent claims. Advantageous embodiments are described in detail in the dependent claims.

[0006] A method for manufacturing an optoelectronic component includes the following steps: A first foil is provided, comprising a top side and a bottom side, wherein at least one optoelectronic semiconductor chip, designed to emit electromagnetic radiation, is disposed on the top side of the first foil. An encapsulation film, at least partially cured, is disposed on the top side of the first foil, wherein the optoelectronic semiconductor chip is embedded in the encapsulation film.

[0007] Since the encapsulation film is at least partially cured, it includes a cross-linked structure. Partial curing can, for example, involve exposing the material of the encapsulation film to ambient conditions for several minutes. However, partial curing can also involve heating the material of the encapsulation film. Partial curing can also be performed for different time spans and, for example, in an inert atmosphere. Advantageously, the encapsulation film can be easily applied without using liquid encapsulation materials. The encapsulation film also acts as a barrier and protects the optoelectronic semiconductor chip. Therefore, robust optoelectronic components can be provided. By selecting the materials of the encapsulation film and the first foil, the compatibility of the optoelectronic component with other systems can be improved.

[0008] In this embodiment, the encapsulation film is at least partially cured by addition curing before it is placed on top of the first foil. Addition curing is performed by mixing two components, a base material and a catalyst, to initiate the curing process. Compared to condensation curing, addition curing advantageously avoids liquid byproducts and shrinkage. Furthermore, addition curing can be performed without forming water or alcohol that could potentially affect the optoelectronic components.

[0009] In this embodiment, after the encapsulation film is placed on the top side of the first foil and the optoelectronic semiconductor chip is embedded in the encapsulation film, the encapsulation film is fully cured. This additional curing step may be necessary if the encapsulation film is initially only partially cured.

[0010] In this embodiment, the encapsulation film is a bi-stage material. A bi-stage material comprises two different cross-linking curing mechanisms or two different critical curing temperatures for the same cross-linking mechanism. Advantageously, these two different curing mechanisms or critical curing temperatures can be used to partially cure the encapsulation film by means of a first curing mechanism or a first curing temperature, thereby placing the encapsulation film on top of the first foil and fully curing the encapsulation film by means of a second curing mechanism or a second curing temperature.

[0011] In one embodiment, a second foil or cover is disposed at the encapsulation film such that the encapsulation film is disposed between the first foil and the second foil or between the first foil and the cover. Advantageously, the optoelectronic semiconductor chip embedded in the encapsulation film is additionally covered by the second foil or cover and thus mechanically protected.

[0012] In an embodiment, plasma treatment and / or corona treatment are performed on the top side of the first foil and / or the additional bottom side of the second foil or cover facing the encapsulation film before the encapsulation film is disposed on the top side of the first foil and / or the second foil or cover facing the encapsulation film. Advantageously, plasma treatment and / or corona treatment of the first foil and / or the second foil or cover can enhance the adhesion between the encapsulation film and the first foil and / or the second foil or cover. Corona treatment is a technique that uses corona discharge plasma, typically in air, to modify the surface by irradiation. Alternatively, any plasma can be used to modify the top side of the first foil or the additional bottom side of the second foil or cover facing the encapsulation film to enhance the adhesion of the foil or cover to the encapsulation film. A dehydration or drying process can be performed on the first foil and / or the second foil or cover before the plasma and / or corona treatment to improve the efficiency of surface modification. However, the drying process and the plasma and / or corona treatment can be omitted.

[0013] In one embodiment, the encapsulation film comprises silicone, and the first foil and / or the second foil or cover comprises polyethylene terephthalate (PET), glass, polymethyl methacrylate (PMMA), or polycarbonate (PC). The encapsulation film, the first foil, and the second foil or cover may also comprise other polymers. The materials of the encapsulation film, the first foil, and the second foil or cover can be selected individually.

[0014] Advantageously, embedding optoelectronic semiconductor chips in silicone ensures stable aging behavior because silicone is generally more thermally and photochemically stable than materials such as PVB, EVA, PMMA, PC, or other polymers. Furthermore, due to the well-known properties of silicone and PET, customers can easily integrate them with other materials. The optoelectronic component includes a bottom interface constructed from the bottom side of a first foil and a top interface constructed from the top side of a second foil or cap opposite the encapsulation film. If the first foil and / or the second foil or cap includes PET, it is highly compatible with many customer integration methods due to the well-known interfaces. Temperature, humidity, and bias tests have demonstrated the robustness of optoelectronic components including top and bottom PET foils. If the second foil or cap is omitted, the top interface is constructed from the surface of the encapsulation film opposite the top side of the first foil (e.g., a silicone surface).

[0015] In this embodiment, the encapsulation film is disposed on the top side of the first foil by a bonding process, and / or the second foil or cap is disposed on the encapsulation film by a bonding process, particularly by printing, dispensing, or lamination. For example, to bond the first foil to the encapsulation film, a vacuum or roll lamination process can be used, embedding the optoelectronic semiconductor chip in the encapsulation film. The cap can be produced by molding, for example by injection molding.

[0016] In this embodiment, a first foil comprising a photoelectric semiconductor chip, an encapsulation film, and a second foil or cover are simultaneously bonded together. Advantageously, the first foil, encapsulation film, and second foil or cover are bonded together in only one method step.

[0017] In another embodiment, the encapsulation film is bonded to the second foil or cover before the first foil, which includes the optoelectronic semiconductor chip, is bonded to the second foil or cover, which includes the encapsulation film. Advantageously, a pre-formed encapsulation film is used on the second foil or cover, which simplifies the handling of the encapsulation film.

[0018] In another embodiment, the encapsulation film is bonded to the first foil before the second foil or cover is bonded to the first foil, which includes the optoelectronic semiconductor chip and the encapsulation film. When the first foil is bonded to the encapsulation film, the optoelectronic semiconductor chip is embedded in the encapsulation material.

[0019] In embodiments, the first foil and / or the second foil or cover includes a non-stick coating, an optical coating, an optical element, a structured surface, an adhesive layer, or a touch-sensitive unit. Advantageously, the first foil and / or the second foil or cover includes additional functions, such as anti-fingerprint, anti-glare, or touch functionality. The interface of the first foil and / or the second foil or cover, or generally an optoelectronic component, can be structured to provide optical functionality. For example, the second foil or cover may include microprisms or microlenses, which can be produced by modifying the morphology of the top interface by structuring the top interface and / or arranging such elements at the top interface. The adhesive layer enhances the adhesion between the encapsulation film and the first foil and / or the second foil or cover.

[0020] In another embodiment, the first foil is bonded to a printed circuit board (PCB), particularly by means of an anisotropic conductive film. The PCB can be designed to be flexible. The anisotropic conductive film comprises conductive spheres dispersed in an adhesive binder. The first foil is bonded to the PCB using temperature and pressure to trap the conductive spheres between the surfaces of conductive traces or bonding pads disposed on the first foil and the PCB. This ensures conductivity in a direction perpendicular to the top side of the first foil, but the spheres are sufficiently insulated from each other to prevent in-plane conductivity. The first foil can also be bonded to the PCB by another method. The first foil can also be bonded to the PCB such that the PCB is disposed on the top side of the first foil.

[0021] The optoelectronic component includes a first foil having a top side and a bottom side opposite the top side. At least one optoelectronic semiconductor chip, designed to emit electromagnetic radiation, is disposed on the top side of the first foil. An encapsulation film is disposed on the top side of the first foil. The optoelectronic semiconductor chip is embedded in the encapsulation film.

[0022] In one embodiment, a second foil or cover is disposed at the encapsulation film such that the encapsulation film is disposed between the first foil and the second foil or between the first foil and the cover.

[0023] In this embodiment, the encapsulation film has been at least partially cured before the optoelectronic semiconductor chip is embedded into it. This means that the encapsulation film comprises at least a partially cross-linked structure before it is arranged on the top side of the first foil and the optoelectronic semiconductor chip is embedded in it.

[0024] In one embodiment, the encapsulation film comprises silicone. The first foil and / or the second foil or cap comprises polyethylene terephthalate (PET), glass, polymethyl methacrylate (PMMA), or polycarbonate (PC). In other embodiments, the first foil, the second foil or cap, and the encapsulation film may comprise other materials that can be selected independently, thereby providing the possibility of using different combinations of materials with preferred properties.

[0025] The above-described features, characteristics, and advantages of the present invention, as well as the ways in which they are realized, will become clearer and more readily understood in conjunction with the following description of exemplary embodiments in conjunction with the accompanying drawings. Here, each case is illustrated schematically:

[0026] Figure 1 A cross-sectional side view of an optoelectronic component based on existing technology;

[0027] Figure 2 : Improved cross-sectional side view of the optoelectronic component;

[0028] Figure 3 :Production Figure 2 A cross-sectional side view of an improved method for photoelectric components;

[0029] Figure 4 :Production Figure 2 A cross-sectional side view of a method for replacing optoelectronic components;

[0030] Figure 5 :Production Figure 2 A cross-sectional side view of an alternative method for optoelectronic components;

[0031] Figure 1 A cross-sectional side view schematically illustrates the photoelectric component 1 according to the prior art.

[0032] The optoelectronic component 1 includes a foil 2 having a top side 3 and a bottom side 4 opposite to the top side 3. Furthermore, an optoelectronic semiconductor chip 5 is disposed on the top side 3 of the foil 2. The optoelectronic semiconductor chip 5 is designed to emit electromagnetic radiation at its light-emitting surface 6, which is opposite to and parallel to the top side 3 of the foil 2. The optoelectronic semiconductor chip 5 may additionally be designed to emit electromagnetic radiation at its side surface extending perpendicular to the top side 3 of the foil 2. Exemplarily, the optoelectronic semiconductor chip 5 is designed as a light-emitting diode (LED). However, the optoelectronic semiconductor chip 5 may also be designed as a laser diode. Furthermore, exemplaryly, four optoelectronic semiconductor chips 5 are disposed on the top side 3 of the foil 2, but any other number of optoelectronic semiconductor chips 5 may be disposed on the top side 3 of the foil 2.

[0033] Encapsulation 7 is arranged on the top side 3 and bottom side 4 of foil 2. A photoelectric semiconductor chip 5 is embedded in encapsulation 7. Encapsulation 7 includes polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), or Sentry Glass. These materials constitute safety glass and are quite specialized.

[0034] according to Figure 1The optoelectronic component 1 has the following disadvantages: the stacking of the foil 2 and the encapsulation 7 is not robust. For example, humidity may cause corrosion and migration. Furthermore, the encapsulation 7 is quite limited due to its specific properties, considering integration with other components or elements. For example, the encapsulation 7 is primarily compatible only with glass. For this reason, a top cover layer 8 and a bottom cover layer 8, including glass, are arranged on the surfaces of the encapsulation 7 facing away from the top side 3 and bottom side 4 of the foil 2, such that the encapsulation 7, with the foil 2 embedded, is arranged between the top cover layer 8 and the bottom cover layer 8. Such a stack can be quite thick, including more than 2 mm. Therefore, a main surface with known properties is required for customer integration.

[0035] Figure 2 The improved optoelectronic component 10 is schematically shown in a cross-sectional side view.

[0036] Figure 2 The optoelectronic component 10 includes the following similarities: at least one optoelectronic semiconductor chip 5, designed to emit electromagnetic radiation, is arranged on the top side 3 of a foil 2, referred to in the following description as the first foil 2. Similarly, any number of optoelectronic semiconductor chips 5 can be arranged on the top side 3 of the first foil 2. For example, Figure 2 The optoelectronic component 10 may include an array of optoelectronic semiconductor chips 5. The optoelectronic component 10 may be designed, for example, as a car taillight.

[0037] replace Figure 1 The encapsulation 7 has an encapsulation film 9 disposed on the top side 3 of the first foil 2. A photoelectric semiconductor chip 5 is embedded in the encapsulation film 9. The photoelectric semiconductor chip 5 is embedded in the encapsulation film 9 such that its light-emitting surface 6 is completely covered by the encapsulation film 9. The encapsulation film 9 exemplarily comprises silicone. However, the encapsulation film 9 may also comprise other polymers and materials.

[0038] Exemplarily, during the method of producing the optoelectronic component 10, the encapsulation film 9 has been at least partially cured by addition curing before the encapsulation film 9 is disposed on the top side of the first foil and at least one optoelectronic semiconductor chip 5 is embedded in the encapsulation film 9. This allows the optoelectronic component 10 to be produced without the use of liquid encapsulation materials. Furthermore, addition curing has the advantage of not forming liquid byproducts that could cause partial corrosion of the optoelectronic component 10. Generally, the handling of at least pre-cured encapsulation film 9 is simplified.

[0039] Other curing mechanisms can also be used to pre-cure the encapsulation film 9. The encapsulation film 9 may, for example, comprise a two-stage material that can be partially cured using a first curing mechanism or a first curing temperature. After the encapsulation film 9 has been arranged on the top side 3 of the first foil 2, it can be fully cured, for example, using a second curing mechanism or a second curing temperature. However, before arranging the encapsulation film 9 on the top side 3 of the first foil 2 and embedding the optoelectronic semiconductor chip 5 within the encapsulation film 9, the encapsulation film 9 must be at least partially cured. For example, exposing silicone to ambient conditions for ten minutes may be sufficient to prepare an at least partially cured encapsulation film 9. Depending on the material chosen, the curing method and parameters may vary.

[0040] The optoelectronic component 10 also includes a second foil 11. The second foil 11 is disposed on the surface 12 of the encapsulation film 9. Instead of the second foil 11, the optoelectronic component 10 may include a cover 11 disposed on the surface 12 of the encapsulation film. The cover 11 may be manufactured by means of molding technology, particularly by injection molding. In the following description, for simplicity, only features associated with the second foil 11 are described. However, all described embodiments including the second foil 11 may alternatively include the cover 11. Furthermore, the cover 11 itself may include all the described features of the second foil 11. The second foil 11 or the cover 11 may be omitted.

[0041] The second foil 11 includes an additional top side 13 and an additional bottom side 14 opposite to the additional top side 13. The second foil 11 is disposed on the surface 12 of the encapsulation film 9 with its additional bottom side 14. Thus, the encapsulation film 9 is disposed between the first foil 2 and the second foil 11. The additional top side 13 of the second foil 11 forms the top interface of the optoelectronic component 10. The first foil 2 and / or the second foil 11 comprise polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), or polycarbonate (PC). PET has the advantage of good adhesion to the encapsulation film 9, which includes silicone.

[0042] The bottom side 4 of the first foil 2 forms the bottom interface of the photoelectric component 10. However, the second foil 11 can be omitted. In this case, the surface 12 of the encapsulation film 9 forms the top interface of the photoelectric component 10. In both cases, the top and bottom interfaces can be well-known and compatible with many other material systems. In summary, Figure 2 10 ratio of optoelectronic components Figure 1 The optoelectronic component 1 is more robust and more compatible with other materials.

[0043] The first foil 2 and / or the second foil 11 may optionally include a non-stick coating, an optical coating, optical elements, a structured surface, or a touch-sensitive unit for additional functions. For simplicity, in Figure 2This additional function is not shown. Such elements, coatings, and structures can be formed on the bottom side 4 of the first foil 2 and / or the additional top side 13 of the second foil 11. Furthermore, the first foil 2 and / or the second foil 11 may optionally include an adhesive layer formed on the top side 3 of the first foil 2 and / or the additional bottom side 14 of the second foil 11 to enhance adhesion to the encapsulation film 9 and the first foil 2 and / or the second foil 11.

[0044] exist Figure 2 In this embodiment, a first foil 2 is bonded to a printed circuit board (PCB) 15 by means of an anisotropic conductive film. The first foil 2 is bonded to the PCB 15 such that the PCB 15 is partially disposed on the top side 3 of the first foil 2. The first foil 2 includes conductive paths and contact pads electrically connected to an optoelectronic semiconductor chip 4 disposed on the top side 3 of the first foil 2. The PCB 15 includes additional conductive paths and additional contact pads, wherein the additional contact pads are disposed on the bottom side of the PCB 15 facing the top side 3 of the first foil 2. The anisotropic conductive film is disposed between the first foil 2 and the bottom side of the PCB 15, and between the contact pads and the additional contact pads, which are disposed on top of each other. The anisotropic conductive film electrically connects the contact pads and the additional contact pads. Figure 2 Anisotropic conductive films are not shown.

[0045] The first foil 2 can also be bonded to the PCB 15 by another method. The PCB 15 can be formed to be flexible; however, since the first foil 2 and the optional second foil 11 are flexible, this is not necessary but may be convenient. The PCB 15 can also be omitted.

[0046] Figure 3 The production basis is shown schematically. Figure 2 The method of the photoelectric component 10. Similarly, the elements of the photoelectric component 10 are shown in a cross-sectional side view. Figure 2 The attached figures are labeled with reference to the figures.

[0047] The method includes the following steps: providing a first foil 2, the first foil comprising, wherein at least one optoelectronic semiconductor chip 5 is disposed on the top side 3 of the first foil 2. The first foil 2 can be exemplarily as shown in... Figure 3 It is attached to PCB 15 as shown.

[0048] In another method step, a partially cured encapsulation film 9 is disposed on the top side 3 of the first foil 2, wherein the optoelectronic semiconductor chip 5 is embedded in the encapsulation film 9. The encapsulation film 9 is at least partially cured before being disposed on the top side 3 of the first foil 2. This means that the encapsulation film 9 includes a structure that is at least partially cross-linked, for example, by addition curing.

[0049] The encapsulation film 9 can be arranged on the top side 3 of the first foil 2 by a bonding process, such as by lamination or printing. The second foil 11 can also be arranged on the encapsulation film 9 by a bonding process, particularly by printing or lamination. Figure 3 A variation of the method is shown, in which the first foil 2, the encapsulation film 9, and the second foil 11 are simultaneously bonded together, for example, by vacuum or by roller lamination.

[0050] Figure 4 Another variation of this method is shown. Figure 4 The methods include with Figure 3 The methods are similar. In the following description, only the similarities between the methods will be described. Figure 4 Methods and Figure 3 The differences between the methods. Maintain Figure 3 The attached figures are labeled with reference to the figures.

[0051] In this case, the encapsulation film 9 is bonded to the second foil 11 before the first foil 2, which includes the optoelectronic semiconductor chip 5, is bonded to the second foil 11, which includes the encapsulation film 9, for example by vacuum or roll lamination.

[0052] Figure 5 Another variation of this method is shown. Figure 5 The methods include with Figure 3 The methods are similar. In the following description, only the similarities between the methods will be described. Figure 5 Methods and Figure 3 The differences between the methods. Maintain Figure 3 The attached figures are labeled with reference to the figures.

[0053] In this variation of the method, the encapsulation film 9 is bonded to the first foil 2 before the second foil 11 is bonded to the first foil 2, which includes the optoelectronic semiconductor chip 5 and the encapsulation film 9. Figure 3 , Figure 4 and Figure 5 In all the cases described, the first foil 2 has been exemplary bonded to the PCB 15 before the encapsulation film 9 and the second foil 11 are laid. In each case, the second foil 11 may be omitted.

[0054] The invention has been shown and described in detail with reference to preferred exemplary embodiments. However, the invention is not limited to the disclosed examples. Rather, those skilled in the art can derive other variations therefrom without departing from the scope of the invention.

[0055] Figure Labels

[0056] 1. Photoelectric components according to existing technology

[0057] 2 foils / First foil

[0058] 3 Top side of the first foil

[0059] 4. The bottom side of the first foil

[0060] 5. Optoelectronic semiconductor chips

[0061] 6. Light-emitting surface of optoelectronic semiconductor chips

[0062] 7. Encapsulation

[0063] 8. Covering layer

[0064] 9. Encapsulation film

[0065] 10. Photoelectric component according to the present invention

[0066] 11 Second foil / cover

[0067] 12. Surface of the encapsulation film

[0068] 13 The other top side of the second foil

[0069] 14 The other bottom side of the second foil

[0070] 15 Printed Circuit Board (PCB)

Claims

1. A method for producing an optoelectronic component (10), comprising the following steps: - Provide a first foil (2), the first foil (2) including a top side (3) and a bottom side (4) opposite to the top side (3). in, At least one optoelectronic semiconductor chip (5) designed to emit electromagnetic radiation is arranged on the top side (3) of the first foil (2). - Arrange at least partially cured encapsulation film (9) on the top side (3) of the first foil (2). The optoelectronic semiconductor chip (5) is embedded in the encapsulation film (9).

2. The method according to claim 1, in, The encapsulation film (9) comprises a two-stage material.

3. The method according to any one of the preceding claims, in, Before the encapsulation film (9) is placed on the top side (3) of the first foil (2), the encapsulation film (9) is at least partially cured by addition curing.

4. The method according to any one of the preceding claims, in, Arrange the second foil (11) or cover (11) on the encapsulation film (9) such that the encapsulation film (9) is arranged between the first foil (2) and the second foil (11) or between the first foil (2) and the cover (11).

5. The method according to any one of the preceding claims, in, Before placing the encapsulation film (9) on the top side (3) of the first foil (2) and / or placing the second foil (11) or the cover (11) on the encapsulation film (9), plasma treatment and / or corona treatment are performed on the top side (3) of the first foil (2) and / or the other bottom side (14) of the second foil (11) or the cover (11) facing the encapsulation film (9).

6. The method according to any one of the preceding claims, in, The encapsulation film (9) comprises silicone, and the first foil (2) and / or the second foil (11) or the cover (11) comprises polyethylene terephthalate, glass, polymethyl methacrylate or polycarbonate.

7. The method according to any one of the preceding claims, in, The encapsulation film (9) is arranged on the top side (3) of the first foil (2) by a bonding process, and / or the second foil (11) or the cover (11) is arranged on the encapsulation film (9) by a bonding process, particularly by printing, dispensing or laminating.

8. The method according to claim 7, in, The encapsulation film (9) is bonded to the first foil (2) before the second foil (11) or the cover (11) is bonded to the first foil (2) which includes the optoelectronic semiconductor chip 5 and the encapsulation film (9).

9. The method according to claim 7, in, The first foil (2) including the optoelectronic semiconductor chip (5), the encapsulation film (9), and the second foil (11) or the cover (11) are simultaneously bonded together.

10. The method according to claim 7, in, Before bonding the first foil (2) including the optoelectronic semiconductor chip (5) to the second foil (11) including the encapsulation film (9) or the cover (11), the encapsulation film (9) is bonded together.

11. The method according to any one of the preceding claims, in, The first foil (2) and / or the second foil (11) or the cover (11) includes a non-stick coating, an optical coating, an optical element, a structured surface, an adhesive layer or a touch-sensitive unit.

12. The method according to any one of the preceding claims, in, The first foil (2) is bonded to the printed circuit board (15) by means of an anisotropic conductive film.

13. A photoelectric component (10), Includes a first foil (2), the first foil (2) having a top side (3) and a bottom side (3) opposite to the top side (2). in, At least one optoelectronic semiconductor chip (5) designed to emit electromagnetic radiation is arranged on the top side (3) of the first foil (2). The encapsulation film (9) is disposed on the top side (3) of the first foil. The optoelectronic semiconductor chip (5) is embedded in the encapsulation film (9).

14. The photoelectric (10) component according to claim 11, in, The second foil (11) is disposed at the encapsulation film (9) such that the encapsulation film (9) is disposed between the first foil (2) and the second foil (11).

15. The photoelectric (10) component according to claim 11 or 12, wherein, Before the optoelectronic semiconductor chip (5) is embedded into the encapsulation film (9), the encapsulation film (9) has been at least partially cured.

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