Production of a radiation-emitting component

Abstract

The invention relates to a method for producing a radiation-emitting component, the method comprising providing a carrier having a housing structure, the housing structure being formed from a polymer material and having a cutout. The method further comprises arranging a radiation-emitting semiconductor chip on the carrier in the cutout of the housing structure, and forming a reflective layer at least on the housing structure. Forming the reflective layer comprises electrophoretically depositing reflective particles. A radiation-emitting component is furthermore described.

Description

[0001] MANUFACTURE OF A RADIATION-EMITTING COMPONENT

[0002] DESCRIPTION

[0003] The present invention relates to a method for producing a radiation-emitting component. The invention further relates to a radiation-emitting component.

[0004] This patent application claims priority from German patent application 10 2023 136 869 . 9 , the disclosure of which is hereby incorporated by reference .

[0005] A radiation-emitting component can comprise a radiation-emitting semiconductor chip for generating electromagnetic radiation or light radiation. The component can further comprise a carrier with a housing for supporting and accommodating the semiconductor chip. The semiconductor chip can be an LED (light-emitting diode) chip. The semiconductor chip can be configured to generate UV radiation (ultraviolet radiation), such as short-wave UVC radiation, and can thus be a UVC LED chip.

[0006] For components with a UVC LED chip, there are limitations to the housing design made of a polymer material. This is due to the high-energy UVC radiation, which can cause degradation of the polymer material. Therefore, carriers and housings are typically made of inorganic materials. This can be associated with high manufacturing costs. Metallic coatings such as gold coatings can also be used. However, gold has low reflectivity in the UVC spectrum, so absorption losses can occur during radiation operation.

[0007] The object of the present invention is to provide a solution for an improved radiation-emitting component. This object is achieved by the features of the independent patent claims. Further advantageous embodiments of the invention are specified in the dependent claims.

[0008] According to one aspect of the invention, a method for producing a radiation-emitting component is proposed. The method comprises providing a carrier with a housing structure, wherein the housing structure is formed from a polymer material and has a recess. Further provided are arranging a radiation-emitting semiconductor chip on the carrier in the recess of the housing structure, and forming a reflective layer at least on the housing structure. Forming the reflective layer comprises electrophoretic deposition of reflective particles.

[0009] By producing the reflective layer, which comprises electrophoretic deposition (EPD) of reflective particles, a reflectivity of a housing surface of the housing structure, and also of other surfaces and sections of the radiation-emitting component, can be specifically adjusted and improved. The reflectivity of the reflective layer can relate at least to electromagnetic radiation or light radiation generated by the semiconductor chip during operation. The reflectivity provided can be significantly higher compared to a state without the reflective layer. In addition, the reflective layer can protect the polymer material of the housing structure from the radiation emitted by the semiconductor chip, as well as from scattered radiation.

[0010] The radiation-emitting component manufactured using the proposed method can therefore be characterized by efficient operation with high optical output power. The component can therefore also be realized with a small size or in a small installation space. Furthermore, a targeted or improved radiation characteristic of the component can be achieved by appropriately designing the recess in the housing structure.

[0011] The process also offers the possibility of manufacturing the radiation-emitting component with low manufacturing costs and low manufacturing complexity. This is because a large selection of possible, and therefore cost-effective, plastic or polymer materials is available for the polymer material of the housing structure. The broad selection can be based on the protective effect of the reflective layer. The formation of the housing structure from the respective polymer material can also be carried out using a cost-effective standard process. The electrophoretic deposition for forming the reflective layer can also be carried out cost-effectively using standard equipment.During the deposition process, the reflective particles can be deposited in a targeted manner on one or more surfaces and sections, provided that an appropriate electrical potential is applied at these locations by electrical contact. The use of an active mask is not required for the local deposition of the reflective particles. Furthermore, the deposition can be carried out conformally. Furthermore, good options for in-situ process control and monitoring are available for electrophoretic deposition, so that the deposition process can be carried out reliably.

[0012] Further possible details and embodiments are described below which may be considered for the manufacturing method and for the radiation-emitting component manufactured according to the method.

[0013] The above-mentioned steps of the manufacturing process, i.e., providing the carrier, arranging the semiconductor chip, and forming the reflective layer, can be carried out in the specified order. In the manufactured component, the housing structure can encircle the semiconductor chip in a frame-like manner.

[0014] The manufacturing method can be advantageous for the following embodiment. Here, the semiconductor chip is designed to generate UV radiation (ultraviolet radiation). The UV radiation can be short-wave UVC radiation. Accordingly, the reflective layer is UV-reflective or UVC-reflective. This makes the radiation-emitting component produced using the method suitable for disinfection applications or other UV applications. Due to the reflective layer and the protective effect achievable thereby, the housing structure can be formed using a plastic or polymer material without UV or UVC stability, and UV stability of the polymer material can thus be omitted as a selection criterion for the production of the component.

[0015] During electrophoretic deposition, the reflective particles can be deposited at least on the housing structure, and here at least or among other things in the region of the recess, on a surface of the housing structure.

[0016] The electro-deposited reflective particles may also exhibit poor adhesion to the surface(s) coated with the particles. The following process variants may be considered to improve adhesion.

[0017] In a further embodiment, the formation of the reflective layer comprises sintering the reflective particles after electro-deposition. In this way, a compaction of the reflective particles, and thus a solidification and stabilization of the reflective layer, resulting in improved fixation and surface adhesion, can be achieved. The aforementioned sintering can be used with regard to a possible embodiment of the reflective particles as polymer particles. In this case, the sintering can cause partial bonding and / or flowing of the reflective particles.

[0018] In a further embodiment, the reflective particles are polytetrafluoroethylene particles. Such particles, and thus the reflective layer formed from the particles, can be characterized by high UVC reflectivity. In this respect, the use of polytetrafluoroethylene particles can be applied with regard to the above-mentioned design of the semiconductor chip for generating UV or UVC radiation. Sintering of polytetrafluoroethylene particles can be carried out at a temperature in the range of 300°C.

[0019] In a further embodiment, the formation of the reflective layer comprises applying a radiation-permeable encapsulation material after the electrophoretic deposition of the reflective particles. The encapsulation material, with which at least an upper part of the reflective particles can be coated and encapsulated, can fix the reflective particles and stabilize the reflective layer, and thus improve surface adhesion. The radiation permeability of the encapsulation material can relate at least to the radiation generated by the semiconductor chip during operation. The encapsulation material can be applied in the form of a thin cover layer.

[0020] The encapsulation material can be a polysiloxane. Such a material can be applied in a simple and cost-effective manner, for example by dipping, dispensing, or spraying. If the semiconductor chip is designed to generate UV or UVC radiation, a UV-stable, at least partially fluorinated polysiloxane can be used. A fluoropolymer can also be used as the encapsulation material. Such a material can be UV-stable and applied, for example, by spraying.

[0021] Alternatively, the encapsulation material can be an oxide material such as silicon or aluminum oxide. A suitable deposition process, such as CVD (chemical vapor deposition), can be used to apply such an encapsulation material, which is also UV-stable.

[0022] The above-mentioned application of an encapsulation material can be used with regard to a possible design of the reflective particles as inorganic particles.

[0023] In a further embodiment, the reflective inorganic particles are particles of barium sulfate, particles of yttrium phosphate, or particles of gadolinium phosphate. It is also possible for the reflective inorganic particles to comprise a particle mixture of several different ones of the aforementioned particles. Such particles, and thus the reflective layer formed from the particles, can also have high UVC reflectivity and can therefore be used with respect to the above-mentioned design of the semiconductor chip to generate UV or UVC radiation.

[0024] Electrophoretic deposition can be carried out using a container with a coating bath therein. The coating bath can comprise a liquid or a solvent and the reflective particles in an undissolved state. The reflective particles can be electrically charged or ionized. For this purpose, the reflective particles can be activated so that the particles are surrounded by an ionic shell and are thus electrically charged. Activation can be effected with an activating material. For particles made of polytetrafluoroethylene, the activating material can be a carboxylic acid such as oleic acid or lithocholic acid, and for particles made of barium sulfate, the activating material can be yttrium nitrate.

[0025] Due to the electrical charge, under the influence of an electric field, a movement of the reflective particles towards the surface(s) to be coated and a deposition of the reflective particles thereon can be brought about. For this purpose, the carrier or components thereof to be coated, such as the housing structure, can be subjected to an electrical potential, as a result of which it(s) can be electrically charged and act as an electrode. Furthermore, a further electrode provided with a different electrical potential can be used. For the deposition process, the carrier and the further electrode can be at least partially immersed in the coating bath.

[0026] In order to apply an electrical potential to the carrier in order to carry out the electrophoretic deposition, the carrier can have an electrical or metallic conductor structure, which can be adjacent to the housing structure. The conductor structure can furthermore be used in the produced radiation-emitting component for external contacting, and thus for electrically supplying the component and its semiconductor chip. For the electrophoretic deposition, the conductor structure can be contacted and subjected to an electrical potential. The conductor structure can have one or more external contacts on the rear, which can be contacted for the deposition process. The conductor structure can furthermore have a connection contact, to which the housing structure or the polymer material can be connected.

[0027] The semiconductor chip of the radiation-emitting component can be configured to generate light radiation. The semiconductor chip can also be an LED (light-emitting diode) chip. With regard to the aforementioned generation of UV or UVC radiation, the semiconductor chip can be a UV or UVC LED chip.

[0028] The semiconductor chip can have contacts via which electrical energy can be supplied to the semiconductor chip. The conductor structure of the carrier can have corresponding mating contacts. In the method, an electrical connection can be established between the contacts of the semiconductor chip and the mating contacts of the conductor structure. This can be done as part of arranging the semiconductor chip on the carrier. The contacts and mating contacts can be mechanically and electrically connected to one another using an electrically conductive connecting material, for example a solder or an electrically conductive adhesive.

[0029] The semiconductor chip can further be a volume emitter configured to emit radiation via a front side and lateral sides. This can facilitate cost-effective production of the radiation-emitting component.

[0030] During electrophoretic deposition, the reflective particles can be deposited, and thus the reflective layer can be formed, on the housing structure, at least in the region of its recess. The reflective particles can also be deposited on a portion of the carrier's conductor structure, including in the region of the mating contacts and in the region of the semiconductor chip contacts. In this way, high reflectivity can be provided not only in the region of the housing structure, but also at these locations, and absorption losses at these locations and at the conductor structure can therefore be avoided.

[0031] In a further embodiment, the carrier has a carrier plate on which the housing structure is arranged. The carrier plate is provided with a conductor structure. This can be the conductor structure described above and used at least for carrying out the electrophoretic deposition. In addition to the conductor structure, the carrier plate can have an electrically non-conductive carrier material. The carrier material can be a ceramic carrier material, and to this extent the carrier plate can be a ceramic carrier plate.

[0032] The electrophoretic deposition of reflective particles on the housing structure requires that it be subjected to an electrical potential and thus electrically charged. In this context, the following configurations may be considered.

[0033] In a further embodiment, the polymer material of the housing structure is an intrinsically conductive polymer material, i.e., a polymer material that is electrically conductive itself. Possible examples of this are doped polythiophene or polypyrrole. During electrophoretic deposition, the reflective particles can be deposited in a targeted manner on a polymer surface of the intrinsically conductive polymer material. For this purpose, an electrical potential can be applied to the polymer material via the aforementioned conductor structure of the carrier, to which the polymer material can be adjacent.

[0034] In a further embodiment, the polymer material of the housing structure is an extrinsically conductive polymer material. In this embodiment, the polymer material itself may not be electrically conductive, and the conductivity may be achieved by an electrically conductive particulate filler contained in the polymer material. Soot particles or metallic particles such as aluminum particles may be used as the filler. In this embodiment, too, the reflective particles can be deposited in a targeted manner on a polymer surface of the polymer material during electrophoretic deposition. In a corresponding manner, an electrical potential can be applied to the polymer material via the above-mentioned conductor structure of the carrier, to which the polymer material may be adjacent.

[0035] In a further embodiment, the housing structure has an electrically conductive coating arranged on the polymer material, on which the reflective layer is formed. In this configuration, the housing structure is not formed solely from the polymer material, but the housing structure additionally has the conductive coating arranged on the polymer material. The polymer material itself can be electrically non-conductive. When providing the carrier, the housing structure can first be formed from the polymer material without the conductive coating, and the conductive coating can subsequently be produced. The conductive coating can be a metallic coating, for example made of gold, aluminum, titanium or nickel. Furthermore, the conductive coating can be produced using a sputtering process in combination with a lift-off method.During electrophoretic deposition, the reflective particles can be deposited in a targeted manner onto the conductive coating. For this purpose, an electrical potential can be applied to the conductive coating via the carrier's conductor structure described above. For this purpose, the conductive coating can be created in such a way that it borders the conductor structure.

[0036] In the aforementioned embodiment, the conductive coating together with the reflective layer can achieve the aforementioned protective effect for the polymer material of the housing structure. The reflective layer can provide a reflectivity that is higher than the reflectivity achievable via the conductive coating alone. As indicated above, the housing structure can be formed using standardized manufacturing processes.

[0037] In a further embodiment carried out in this sense, the provision of the carrier comprises applying the polymer material of the housing structure by carrying out a molding process. The molding process, also referred to as a molding process, can be carried out using a suitable molding tool. In this case, the housing structure and its recess can be produced in a targeted and reliable manner with a predetermined geometric shape. For example, the housing structure can be provided with a reflector geometry in the form of inner walls which run obliquely in cross section to a main extension plane of the carrier and which delimit the recess. As a result, the radiation-emitting component can have a predetermined radiation characteristic.

[0038] In a further embodiment, providing the carrier comprises applying the polymer material of the housing structure by dispensing, spraying, or printing. Such processes can be carried out with little effort and cost-effectively. The polymer material is applied using a dispenser, a spraying device, or a printing device.

[0039] With the aid of the method, not only a single radiation-emitting component but also a plurality of radiation-emitting components can be manufactured together in a composite. In this sense, according to a further embodiment, the housing structure is provided with a plurality of cutouts, a plurality of semiconductor chips are arranged on the carrier in the cutouts, and after the reflective layer has been formed, the components are separated into separate components. This type of processing, which can also be referred to as batch processing, enables cost-effective production of the plurality of radiation-emitting components. The carrier and the housing structure are provided with dimensions and characteristics for the plurality of components. By separating them, which can be carried out by sawing, the carrier can be divided into individual smaller carriers belonging to the respective components.

[0040] With regard to the joint production of a plurality of radiation-emitting components, according to a further embodiment, separation trenches are formed in the housing structure before the formation of the reflective layer, so that the housing structure is divided into individual housing structures assigned to the respective components and having a recess. In this case, the separation comprises severing, in this case the remaining carrier, in the region of the separation trenches. In this method variant, the reflective layer can also be produced in the region of the separation trenches on the individual housing structures belonging to the components. In this respect, the reflective layer can also be present on the lateral outer sides of the respective housing structures in the case of the separated components.

[0041] If the housing structure, as stated above, has a conductive coating arranged on the polymer material, the separating trenches can be formed in a state of the housing structure in which the housing structure only has the polymer material and not yet the conductive coating. After the separating trenches have been formed, the conductive coating can be produced, so that the individual housing structures of the carrier now have the conductive coating.

[0042] According to a further aspect of the invention, a radiation-emitting component is proposed. The component has a carrier with a housing structure. The housing structure is formed from a polymer material and has a recess. A further component of the component is a radiation-emitting semiconductor chip, which is arranged in the recess of the housing structure on the carrier. The component further has a reflective layer at least on the housing structure. The reflective layer comprises electrophoretically deposited reflective particles.

[0043] The aforementioned radiation-emitting component can be manufactured by carrying out the method described above or one or more embodiments of the method described above. All details relating to the method can therefore also be applied to the component, and accordingly all statements made for the component can apply to the method. For example, the reflective layer arranged on the housing structure can provide high reflectivity, which enables efficient radiation operation of the component with high brightness. Furthermore, the polymer material of the housing structure can be protected from radiation generated by the semiconductor chip during operation via the reflective layer. In this way, a large selection of possible materials can be available for the polymer material of the housing structure.The reflective particles can be present as a conformal coating due to electrophoretic deposition.

[0044] The structure of the radiation-emitting component may be expedient in a configuration in which the semiconductor chip is designed to generate UV or UVC radiation, and the reflective layer is UV or UVC reflective. This allows the component to be used, for example, for disinfecting air, water, and / or surfaces.

[0045] In a further embodiment, the reflective particles are sintered additionally or after their electrophoretic deposition. This allows the reflective layer to be solidified and thus stabilized. In a further embodiment, the reflective layer comprises an encapsulation material. In this way, the reflective particles can be fixed, and the reflective layer can thus be stabilized.

[0046] The polymer material of the housing structure can be an intrinsically conductive or extrinsically conductive polymer material. The reflective layer can be arranged on the polymer material. It is also possible for the housing structure to have an electrically conductive coating arranged on the polymer material, on which the reflective layer is formed or arranged.

[0047] The advantageous embodiments and further developments of the invention explained above and / or reproduced in the subclaims can - except, for example, in cases of clear dependencies or incompatible alternatives - be used individually or in any desired combination with one another.

[0048] The above-described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of exemplary embodiments, which are explained in more detail in conjunction with the schematic drawings. In the drawings:

[0049] Figure 1 is a side view of a radiation-emitting component;

[0050] Figures 2 and 3 are top views of components of the radiation-emitting component of Figure 1;

[0051] Figures 4 to 18 show a process sequence for producing radiation-emitting components with a structure corresponding to Figure 1, which comprises an electrophoretic deposition of reflective particles; Figures 19 and 20 show process steps which are carried out during the electrophoretic deposition;

[0052] Figures 21 and 22 show process steps for stabilizing electrophoretically deposited particles;

[0053] Figures 23 and 24 show a further process sequence for the production of radiation-emitting components;

[0054] Figures 25 to 27 show a further process sequence for the production of radiation-emitting components;

[0055] Figure 28 is a representation of an extrinsically conductive polymer material; and

[0056] Figures 29 to 32 show a further process sequence for the production of radiation-emitting components.

[0057] Embodiments of a radiation-emitting component 100 and an associated manufacturing method are described on the basis of the schematic figures. It is pointed out that the schematic figures may not be true to scale. Therefore, components and structures shown in the figures may be exaggeratedly large or reduced in size for better understanding. In addition, it is pointed out that features and details mentioned in relation to one embodiment may also be used for other embodiments, and multiple embodiments and their features may be combined with one another. Corresponding features may in this case be described in detail only with reference to one embodiment.

[0058] Figure 1 shows a side view of a radiation-emitting component 100. For better illustration, Figures 2 and 3 additionally show top views of components of the component 100. The component 100 has a radiation-emitting semiconductor chip 150 for generating light radiation 200 and a carrier 105 for supporting and receiving the semiconductor chip 150. The carrier 105 has a ceramic carrier plate 130 and a housing structure 110 arranged on the carrier plate 130 and formed from a plastic or polymer material 120. The carrier plate 130 is provided with an electrical or metallic conductor structure 140.

[0059] The ceramic carrier plate 130 has two opposite main sides, i.e. sides with the largest surface area, i.e. a front side located at the top in Figure 1 and an opposite rear side. The front side is also referred to below as the mounting side 131. As illustrated in Figure 2, the carrier plate 130 can have a rectangular or square shape when viewed from above. The housing structure 110 arranged on the carrier plate 130 has a recess 111 within which the semiconductor chip 150 is arranged on the carrier plate 130. The housing structure 110 and the semiconductor chip 150 are located on the mounting side 131 of the carrier plate 130.

[0060] The conductor structure 140 comprises, as shown in Figure 1, two mating contacts 141 provided for connection to the semiconductor chip 150, a connection contact 142 provided for connection to the housing structure 110 or its polymer material 120, two external contacts 144 serving to electrically contact the radiation-emitting component 100, and three through contacts 143 extending through the carrier plate 130. Each of the mating contacts 141 is connected to one of the external contacts 144 via a through contact 143. The connection contact 142 is likewise connected to one of the external contacts 144 via a further through contact 143. The mating contacts 141 and the connection contact 142 are located on the mounting side 131 of the carrier plate 130 , and the external contacts 144 are present on the opposite rear side of the carrier plate 130 .Figure 2 clearly shows that, viewed from above, the connecting contact 142 has a rectangular or square frame shape surrounding the mating contacts 141. In Figure 2, the through contacts 143 of the conductor structure 140 are also indicated by dashed lines. The rear external contacts 144 of the conductor structure 140 can be used, for example, as soldering pads of the component 100.

[0061] The semiconductor chip 150 of the radiation-emitting component 100 is a volume emitter which emits the light radiation 200 generated during operation, as indicated by arrows in Figure 1, via a front side located at the top in Figure 1 and lateral side walls running perpendicular thereto. The semiconductor chip 150 is further implemented in the form of a flip chip with two contacts 151 on a rear side opposite the front side. Electrical energy for generating radiation can be supplied to the semiconductor chip 150 via the contacts 151. As shown in Figure 3, the semiconductor chip 150 can have a rectangular or square top view and accordingly four lateral side walls. The semiconductor chip 150 can be a light-emitting diode or LED chip.The semiconductor chip 150 can further be configured to generate UV radiation (ultraviolet radiation), such as short-wave UVC radiation, and thus be a UVC LED chip. As a result, the component 100 can be used, for example, for disinfecting air, water, and / or surfaces, or for other UV applications.

[0062] The semiconductor chip 150 is, as shown in Figure 1, mechanically and electrically connected to the carrier plate 130. The rear side of the semiconductor chip 150 lies opposite the mounting side 131 of the carrier plate 130, and the semiconductor chip 150 is mounted with the contacts 151 on the mating contacts 141 of the conductor structure 140. A connection between the contacts 151 and the mating contacts 141 is produced via an electrically conductive connecting material 160. In this way, the semiconductor chip 150 can be electrically supplied via the conductor structure 140 during radiation operation of the component 100. The conductive connecting material 160 can be a solder or an electrically conductive adhesive.

[0063] According to the schematic representation of Figure 1, the semiconductor chip 150 has an active region 155, or the region that generates the light radiation 200, which is located on the rear side of the semiconductor chip 150 with the contacts 151. The radiation-generating region 155 can be formed by a semiconductor layer sequence. The semiconductor chip 150 can further have a radiation-transmissive chip substrate made of, for example, sapphire, which can form the front side and a predominant part of the lateral sidewalls of the semiconductor chip 150. In this respect, the semiconductor chip 150 can be a volume-emitting sapphire flip chip.

[0064] The semiconductor chip 150 arranged in the recess 111 of the housing structure 110 is laterally enclosed by the housing structure 110. The housing structure 110, together with the carrier plate 130, forms a cavity open to one side. Viewed in plan view, the housing structure 110, as shown in Figure 3, has a rectangular or square frame shape surrounding the semiconductor chip 150. The housing structure 110 is also arranged on the surrounding connection contact 142 of the conductor structure 140. The connection contact 142 is, except for one inside opposite the housing structure

[0065] 110 protruding portion, covered with the housing structure 110, as is clear from Figures 1 and 3.

[0066] The housing structure 110 has a laterally inwardly directed recess facing the semiconductor chip 150 and the recess

[0067] 111, a circumferential inner side 112, a circumferential front side 113, and a laterally outwardly directed circumferential outer side 114. Both the outer side 114 and the inner side 112 each comprise four side walls. Figure 1 shows that the side walls of the inner side 112 run obliquely in cross section to a main extension plane of the carrier 105 or the carrier plate 130, and the side walls of the outer side 114 run perpendicular in cross section to the main extension plane. As further shown in Figure 3, there can be rounded transitions between the side walls of the inner side 112, whereas the side walls of the outer side 114 are directly adjacent to one another. As an alternative to this, the rounded transitions can be omitted, so that the side walls of the inner side 112 can be directly adjacent to one another, separated by corresponding edges.

[0068] Due to the slanted inner walls of the inner side 112, the housing structure 110, together with a reflective layer 170 of the radiation-emitting component 100, can serve as a reflector for reflecting the light radiation 200 emitted by the semiconductor chip 150. As a result, the component 100 can have a predetermined radiation characteristic.

[0069] The reflective layer 170, which is present on the carrier 105 in various separate subregions, is arranged, as shown in Figure 1, among other things, on the housing structure 110. The inner side 112, the front side 113 and the outer side 114 of the housing structure 110 are completely covered with the reflective layer 170. The reflective layer 170 is also located on the connection contact 142 of the conductor structure 140, i.e. on the subregion projecting beyond the inside of the housing structure 110 and on a lateral edge thereof. The reflective layer 170 or further sections thereof are also present in the region of the contact points of the semiconductor chip 150. Here, the contacts 151 of the semiconductor chip 150, the mating contacts 141 of the conductor structure 140 and the connecting material 160 connecting the contacts 151 and mating contacts 141 are covered with the reflective layer 170 in an edge region.In the top view of Figure 3, the reflective layer 170 is omitted.

[0070] The reflective layer 170 is produced during the production of the radiation-emitting component 100 of Figure 1, among other things, by electrophoretic deposition (ERD) of reflective particles 171 (cf. Figures 9 and 20), as will be explained further below. The reflective layer 170 can provide a high reflectivity with regard to the light radiation 200 emitted by the semiconductor chip 150 during radiation operation, so that the light radiation 200 can be reflected efficiently by the layer 170. As a result, the radiation operation of the component 100 can take place with a high optical output power. With regard to the above-mentioned configuration of the semiconductor chip 150 for generating UV or UVC radiation, the reflective layer 170 and the reflective particles 171 UV- or UVC-reflective.

[0071] Because the reflective layer 170 is also located in the area of ​​the contact points of the semiconductor chip 150 and on the conductor structure 140 in the area of ​​the mounting side 131 of the carrier plate 130, absorption losses at these locations can be avoided. For example, the conductor structure 140 can have a gold coating on the outside with low reflectivity in the UVC spectrum. Absorption can be prevented by the reflective layer 170.

[0072] A further advantage is that the polymer material 120 of the housing structure 110 can be reliably protected by the reflective layer 170 from the light radiation 200 generated by the semiconductor chip 150 during operation. In this respect, a large selection of possible, and therefore also cost-effective, materials is available for the polymer material 120. With regard to the design of the semiconductor chip 150 for generating UV or UVC radiation, the polymer material 120 does not require any UV or UVC stability, and thus any stability of the polymer material 120 with respect to UV or UVC radiation can be omitted as a selection criterion for the production of the component 100. Furthermore, production can thus be cost-effective.

[0073] A possible method for producing a plurality of radiation-emitting components 100 having the structure explained above with reference to Figures 1 to 3 is described below using side views and top views. The components 100 are produced in a composite, thus resulting in batch processing. The figures show a section of the production process, so that the conditions presented here can be repeated many times.

[0074] As shown from the side in Figure 4 and in plan view in Figure 14, at the beginning of the method a ceramic carrier plate 130 provided with an electrical conductor structure 140 is provided. The carrier plate 130 has a design and dimensions for the plurality of components 100 to be produced. In this respect, for each of the components 100, a circumferential connection contact 142 and two mating contacts 141 are provided on a mounting side 131 of the carrier plate 130, and two external contacts 144 are provided on an opposite rear side of the carrier plate 130. The conductor structure 140 further has through contacts 143 penetrating the carrier plate 130 and connecting the respective contacts 141, 142, 143.

[0075] Subsequently, as shown in Figure 5 from the side and in Figure 15 in plan view, a housing structure 110 made of a polymer material 120 is formed on the mounting side 131 of the carrier plate 130, so that a carrier 105 comprising the carrier plate 130 and the housing structure 110 is provided. The housing structure 110 is likewise tailored to the production of the plurality of components 100 and accordingly has a recess 111 for each of the components 100. Viewed in plan view, the housing structure 110 has the shape of a grid enclosing the individual recesses 111 (cf. Figure 15). Each recess 111 is laterally delimited by a circumferential inner side 112 of the housing structure 110. The inner sides 112 have inner walls which, in cross section, extend obliquely to a main extension plane of the support 105 and the support plate 130.The housing structure 110 further has, adjacent to the inner sides 112, a front side 113 which also runs in a grid shape. The housing structure 110 is formed on the mounting side 131 of the carrier plate 130 in such a way that the connection contacts 142 of the conductor structure 140 are covered with the housing structure 110, except for a partial area protruding on the inside relative to the housing structure 110 in the region of the recesses 111. Next to and between the connection contacts 142, the housing structure 110 borders the carrier plate 130 or a ceramic carrier material thereof. The mating contacts 141 of the conductor structure 140 located in the region of the recesses 111 are free of the housing structure 110.

[0076] The housing structure 110 is formed from the polymer material 120 by carrying out a molding process (also referred to as a molding process). This can be compression molding. The molding process is carried out using a suitable molding tool (not shown). Due to the molding process, the housing structure 110 and its recesses 111 can be reliably produced with a predetermined geometric shape on the carrier plate 130. The polymer material 120 used can be an electrically conductive, i.e., intrinsically or extrinsically conductive, polymer material 120 with a view to a later electrophoretic deposition. This will be discussed in more detail below.

[0077] This is followed by chip assembly, in which radiation-emitting semiconductor chips 150 are arranged within the recesses 111 of the housing structure 110 on the mounting side 131 of the carrier plate 130, as shown from the side in Figure 6 and in plan view in Figure 16. A semiconductor chip 150 is placed in each recess 111. During this process, the contacts 151 of the semiconductor chips 150 are connected to the mating contacts 141 of the conductor structure 140 via an electrically conductive connecting material 160. The connecting material 160 can be a solder or an electrically conductive adhesive, so that the chip assembly can be carried out by soldering or gluing. The semiconductor chips 150 can be volume-emitting UVC-LED chips.

[0078] Thereafter, as shown in Figure 7 from the side and in Figure 17 in plan view, separating trenches 210 are formed in the housing structure 110 in regions between the connection contacts 142, whereby the housing structure 110 is divided into individual smaller housing structures 110, each belonging to one of the components 100 and each having a recess 111. Viewed in plan view, the separating trenches 210 together form the shape of a coherent grid-shaped trench structure. The production of the separating trenches 210 can be carried out by sawing. When forming the separating trenches 210, a part of the carrier plate 130 or of its ceramic carrier material in the region of the mounting side 131 can also be removed or ablated.

[0079] The carrier 105 present after the formation of the separating trenches 210 now comprises the carrier plate 130 and the individual housing structures 110 located thereon. The housing structures 110 have the configuration explained with reference to Figures 1 and 3, with the circumferential front side 113 and the circumferential lateral outer side 114. The purpose of forming the separating trenches 210 is to also provide the outer sides 114 of the housing structures 110 with the reflective layer 170 during a subsequent formation of a reflective layer 170 on the carrier 105. The reflective layer 170 is produced as follows on the carrier 105 in the region of the mounting side 131 and on the housing structures 110.

[0080] The formation of the reflective layer 170 comprises an electrophoretic deposition of reflective particles 171. This process requires the components to be coated to be subjected to an electrical potential so that they are electrically charged. In the present case, this is achieved, among other things, via the conductor structure 140 of the carrier plate 130. As shown in the side view of Figure 8, the carrier plate 130 of the carrier 105 is arranged for this purpose with its rear side on a metallic electrode plate 185, so that the external contacts 144 of the conductor structure 140 rest against the electrode plate 185 or are electrically contacted by it. In this way, conductive components 150 present in the region of the mounting side 131 can be subjected to an electrical potential via the electrode plate 185 and the external contacts 144 and through contacts 143 of the conductor structure 140.This concerns the connecting contacts 142 and counter contacts 141 of the conductor structure 140, as well as, via these, the conductive polymer material 120 of the housing structures 110, the connecting material 160, and the contacts 151 of the semiconductor chips 150. These components can therefore act as an electrode for the electrophoretic deposition.

[0081] The electrophoretic deposition of the reflective particles 171 is carried out, as illustrated from the side in Figure 9, using a coating bath 191 containing the reflective particles 171, a further metallic electrode plate 186 in addition to the electrode plate 185 connected to the carrier 105 or the conductor structure 140, and a power source 180 connected to the two electrode plates 185, 186. The coating bath 191 can comprise a liquid or a solvent and the reflective particles 171 present in an undissolved state. The coating bath 191 can also be accommodated in a container 190 (cf. Figure 20). For the deposition process, the carrier 105 can be at least partially immersed in the coating bath 191.

[0082] Different electrical potentials can be applied to the electrode plates 185, 186 via the power source 180. In this case, the reflective particles 171 can be negatively charged, and correspondingly, as shown in Figure 9, a positive electrical potential can be applied to the electrode plate 185 and a negative electrical potential can be applied to the electrode plate 186. In this way, the electrode plate 186 can serve as the cathode 182, and the electrode plate 185 and components electrically connected to the electrode plate 185, such as the housing structures 120, can serve as the anode 181. An electric field exists between anode 181 and cathode 182, so that a movement of the negatively charged reflective particles 171 in the direction of the anode 181 and a conformal coating of the anode 181 with the particles 171 can be caused (cf. additional Figure 20, in which the particle movement is indicated by an arrow).Accordingly, the deposition process can also be referred to as an anodic EPD process or anodic dip coating (ATL). The deposition, and thus the formation of the reflective layer 170, which is initially composed of loose individual particles 171, takes place section by section on the housing structures 110, i.e. on their inner sides 112, front sides 113 and outer sides 114, on the partial regions of the connection contacts 142 that protrude relative to the housing structures 110, and in the region of the connection points of the semiconductor chips 150 on the contacts 151, the connecting material 160 and the mating contacts 141. For illustration, Figure 10 shows a lateral view of the carrier 105 in a state after the electrophoretic deposition has been carried out and after the carrier 105 has been removed from the coating bath 191.

[0083] The electrophoretic deposition can be performed using in-situ process control and monitoring. This allows the deposition of the reflective particles 171 on the carrier 105 to be carried out with high reliability and in a specified manner.

[0084] With regard to the reflective particles 171 used, different designs can be used. In semiconductor chips 150 for generating UV or UVC radiation, the particles 171 can be polymer particles made of polytetrafluoroethylene (PTFE). This material is UV or UVC stable and is characterized by high UVC reflectivity. Accordingly, the reflective layer 170 formed from such particles 171 can have high UVC reflectivity.

[0085] Alternatively, the reflective particles 171 can be inorganic particles, and with regard to semiconductor chips 150 for generating UV or UVC radiation, particles made of barium sulfate (BaSO4), yttrium phosphate (YPO4), or gadolinium phosphate (GdPO4). It is also possible to use a particle mixture made of several different particle materials from the aforementioned. Such inorganic materials also have high UVC reflectivity, which accordingly applies to a reflective layer 170 comprising such particles 171.

[0086] The above-described electrically charged state of the reflective particles 171 used for electrophoretic deposition can be brought about by activating the particles 171. As shown schematically in Figure 19, to prepare for electrophoretic deposition, a suspension 196 comprising the particles 171 can first be provided in a preparation container 195, and an activating material 197 acting on a particle surface of the particles 171 can then be added to the suspension 196 to activate the particles 171. The suspension 196 comprises, in addition to the undissolved reflective particles 171, a liquid or a solvent. The solvent can be ethanol or isopropanol, for example. By adding the activating material 197 to the suspension 196, the particles 171 can be activated, i.e., surrounded by an ion shell and thus electrically charged.For particles 171 made of polytetrafluoroethylene, a carboxylic acid such as oleic acid or lithocholic acid can be used as the activation material 197. For inorganic particles 171 such as particles made of barium sulfate, yttrium nitrate (Y(NO3)3) can be used as the activation material 197. As a result of the activation, the reflective particles 171 can be negatively charged. To provide the above-mentioned coating bath 191, the suspension 196 with the activated particles 171 can subsequently be arranged in the container 190 used for the deposition process, and, as shown schematically in Figure 20, by applying appropriate electrical potentials to the cathode 182 and anode 181 using the current source 180, a migration of the particles 171 away from the cathode 182 towards the anode 181 with a deposition thereon can be caused.

[0087] In the state of the carrier 105 shown in Figure 10 and after the deposition process, the reflective layer 170 comprises only the electrophoretically deposited particles 171. Adhesion of the reflective layer 170 to the respective surfaces may be low. Therefore, in the manufacturing process, following the electrophoretic deposition, a mechanical stabilization of the reflective layer 170 is carried out. Depending on the particles 171 used, the procedure varies.

[0088] When using polymer particles or particles 171 made of polytetrafluoroethylene, as shown in a side view in Figure 11, sintering of the particles 171 is carried out by applying thermal energy 220 to the carrier 105. In this way, the particles 171 can partially adhere to one another and / or partially flow into one another, as illustrated in Figure 21. Associated with this is solidification and stabilization of the reflective layer 170, so that the reflective layer 170 can have improved surface adhesion. Sintering can be carried out at a temperature in the range of 300°C.

[0089] When using inorganic particles or particles made of barium sulfate, yttrium phosphate and / or gadolinium phosphate, a radiation-permeable encapsulation material 175 is applied to the carrier 105 in the region of the housing structures 110 and the mounting side 131 of the carrier plate 130, as shown from the side in Figure 12. This process is additionally shown in Figure 22. The encapsulation material 175 can be applied in the form of a thin cover layer, with which at least an upper part of the reflective particles 171 can be enveloped and thus encapsulated. In this process, the encapsulation material 175 is applied over a large area, and thus not only in the region of the deposited reflective particles 171, but also at other locations on the carrier 105 or the carrier plate 130 and on the semiconductor chips 150.

[0090] For example, a polysiloxane can be used as the encapsulation material 175. The encapsulation material 175 can be applied to the carrier 105, for example, by dipping, dispensing, or spraying. For semiconductor chips 150 for generating UV or UVC radiation, a UV-stable fluorinated or partially fluorinated polysiloxane can be used.

[0091] Alternatively, the encapsulation material 175 may be an oxide material such as silicon oxide (SiO2) or aluminum oxide (Al2O3). In this embodiment, the encapsulation material 175 may be applied to the carrier 105 by performing a deposition process such as a CVD (chemical vapor deposition) process.

[0092] After stabilizing the reflective layer 170, a separation is carried out to provide separate radiation-emitting components 100, as shown from the side in Figure 13 and in plan view in Figure 18. For separation, the carrier 105 is severed in the region of the previously created separation trenches 210 between the housing structures 110 along separation lines 211, so that the carrier 105 and its carrier plate 130 are divided into individual, smaller carriers 105 and carrier plates 130, each associated with one of the components 100. The separation can be carried out, for example, by sawing. In the plan view of Figure 18, the reflective layer 170 is omitted.

[0093] Further variants and embodiments are explained below which may be considered for a radiation-emitting component 100 described here and a corresponding manufacturing method. Corresponding features and aspects, as well as identical and equivalent components, are not described in detail again below. For details, reference is instead made to the above description. Furthermore, reference is made to the possibility of combining features of two or more of the embodiments described here.

[0094] The method sequence described above can be modified such that, contrary to Figures 6 and 7, the formation of the separating trenches 210 in the housing structure 110 is carried out before, rather than after, chip assembly. In this method variant, the semiconductor chips 150 are thus mounted on the carrier plate 130 within the recesses 111 of the individual housing structures 110.

[0095] A further possible modification of the method sequence explained above consists in dispensing with the formation of the separating trenches 210. In this method variant, method steps according to Figures 4 to 6 are first carried out, i.e. forming the housing structure 110 with the cutouts 111 on the carrier plate 130 and carrying out the chip mounting. Subsequently, as shown in a lateral illustration in Figure 23, the reflective layer 170 is formed on the carrier 105 in the region of the mounting side 131. This process comprises the electrophoretic deposition of reflective particles 171 explained above, which are deposited on the (undivided) housing structure 110, i.e.on the inner sides 112 delimiting the recesses 111 and the grid-shaped front side 113 of the housing structure 110, on the partial regions of the connection contacts 142 protruding from the housing structure 110, and in the region of the connection points of the semiconductor chips 150 on the contacts 151, the connecting material 160 and the mating contacts 141. In this case, the housing structure 110 is subjected to an appropriate electrical potential via the conductor structure 140 of the carrier 105 and the electrode plate 185 also used here. After the electrophoretic deposition, the reflective layer 170 is stabilized, which is carried out as described above by sintering the particles 171 or applying the transparent encapsulation material 175.

[0096] This is followed by separation to provide separate radiation-emitting components 100, as shown from the side in Figure 24. For this purpose, the carrier 105, including the reflective layer 170 present on the housing structure 110, is severed along dividing lines 211, so that the carrier 105 and thus its carrier plate 130 and housing structure 110 are divided into individual smaller carriers 105, each associated with one of the components 100, said carriers having a carrier plate 130 and a housing structure 110 surrounding a recess 111 in the form of a frame. The housing structure 110 of a single component 100 thus has a circumferential lateral outer side 114 which, in contrast to the component 100 of Figure 1, is not covered with the reflective layer 170.Since the outer side 114 is not in the direct radiation path of the light radiation 200 emanating from the semiconductor chip 150 during operation, this may not be of any further importance.

[0097] For forming the housing structure 110 from the polymer material 120 with the cutouts 111, a different process can be used instead of a molding process. As a result, the housing structure 110 can have a different shape in cross-section than that shown in the previous figures. For illustration, the lateral views of Figures 25 to 27 show a variant of the manufacturing method carried out in this sense. Here, the housing structure 110 with the cutouts 111 is produced by dispensing the polymer material 120 on the mounting side 131 of the carrier plate 130 in order to provide the carrier 105 shown in Figure 25 for the further production of the radiation-emitting components 100. The application of the polymer material 120 to the carrier plate 130 is carried out in this process using a dispenser (not shown). The housing structure 110 produced in this way has a round or .partially or semi-circular profile. Here, too, the housing structure 110 is formed on the mounting side 131 of the carrier plate 130 in such a way that the connection contacts 142 of the conductor structure 140 are covered with the housing structure 110, except for a partial area protruding from the housing structure 110 in the region of the cutouts 111. Next to and between the connection contacts 142, the housing structure 110 borders on the carrier plate 130. Viewed in plan view, the housing structure 110 can have the shape of a grid enclosing the individual cutouts 111 (not shown).

[0098] The further processes described above then take place, i.e. the chip mounting and the formation of the reflective layer 170 on the carrier 105 in the region of the mounting side 131, so that the process state shown from the side in Figure 26 is present. The formation of the reflective layer 170 comprises the above-explained electrophoretic deposition of reflective particles 171, which are deposited on the housing structure 110, the partial regions of the connection contacts 142 protruding from the housing structure 110, and in the region of the connection points of the semiconductor chips 150 on the contacts 151, the connecting material 160 and the mating contacts 141. The above-explained stabilization of the reflective layer 170 then takes place by sintering the particles 171 or applying the transparent encapsulation material 175.Thereafter, as shown in the side view of Figure 27, a separation is carried out to provide separate radiation-emitting components 100. For this purpose, the carrier 105, including the reflective layer 170 present on the housing structure 110, is severed along separating lines 211, so that the carrier 105 and thus its carrier plate 130 and housing structure 110 are divided into individual smaller carriers 105, each associated with one of the components 100, said carriers having a carrier plate 130 and a housing structure 110 enclosing a recess 111 in the shape of a frame. In the case of a separated component 100, the housing structure 110 therefore has a circumferential lateral outer side 114 which is not covered with the reflective layer 170.

[0099] With regard to the process sequence of Figures 25 to 27, instead of dispensing, the polymer material 120 can also be sprayed or printed in order to form the housing structure 110 on the carrier plate 130 and thereby provide the carrier 105 for the further production of the radiation-emitting components 100. In this case, the housing structure 110 can have a cross-sectional profile corresponding to Figure 25 or a different one. A spraying device can be used for the spraying, and a printing device can be used for the printing (not shown).

[0100] The method sequence of Figures 25 to 27 can further be modified in a manner corresponding to the method sequence of Figures 4 to 13 in that, before the formation of the reflective layer 170, separating trenches 210 are formed in the housing structure 110 in regions between the connection contacts 142, with the result that the grid-shaped housing structure 110 is divided into individual smaller housing structures 110 belonging to the components 100, each with a recess 111. In this variant, by subsequently forming the reflective layer 170 and carrying out the singulation, components 100 can be produced in which the outer sides 114 of the housing structures 110 are covered with the reflective layer 170 (not shown).

[0101] As stated above, the polymer material 120 used to form the housing structure 110 may be an intrinsically conductive polymer material that is electrically conductive by itself. Possible examples of such a self-conductive polymer material are doped polythiophene or polypyrrole.

[0102] Alternatively, the polymer material 120 used can be an extrinsically conductive polymer material. In this embodiment, the polymer material 120 can, as schematically depicted in Figure 28, have a matrix or base material 121 and a filler contained in the base material 121 in the form of electrically conductive particles 122. The electrical conductivity is thereby produced via the filler particles 122. The base material 121 is therefore itself a non-conductive polymer material. The particles 122 can be soot particles or metallic particles, such as aluminum particles.

[0103] It is furthermore possible to form the housing structure 110 not solely from a polymer material 120, but, with regard to the electrophoretic deposition, to additionally provide an electrically conductive coating 125 arranged on the polymer material 120. This is the case with a further method sequence explained below with reference to the lateral views of Figures 29 to 32, which represents a modification of the method sequence explained with reference to Figures 23 and 24. Figures 29 to 32 show the production in detail in the region of a recess 111 and a semiconductor chip 150.

[0104] In this process variant, as shown in Figure 29, a coated housing structure 110, i.e. one having a conductive coating 125, with cutouts 111 is produced on the mounting side 131 of the carrier plate 130 in order to provide the carrier 105 for the further production of the radiation-emitting components 100. For this purpose, a polymer material 120 is applied to the carrier plate 130, so that an initially uncoated housing structure 110 is present on the carrier plate 130, and the electrically conductive coating 125 is subsequently formed on the polymer material 120 and partly on the conductor structure 140 in order to complete the housing structure 110. The polymer material 120 can be electrically non-conductive and can be applied by a molding process.The polymer material 120 can be arranged in the form of a grid on the carrier plate 130, so that a design of the housing structure 110 corresponding to Figure 15 can be present when viewed in plan view.

[0105] In the housing structure 110 shown in Figure 29, the inner sides 112, which laterally delimit the recesses 111 of the housing structure 110, and the front side 113 of the housing structure 110 are formed by the conductive coating 125. The coating 125 is located not only on the polymer material 120, but also laterally of the polymer material 120 on the connection contacts 142 of the conductor structure 140. This serves the purpose of the coating 125 being electrically connected to the conductor structure 140. The connection contacts 142 can be partially covered with the coating 125, as shown in Figure 29.

[0106] The conductive coating 125 can be formed from a metallic material such as gold, aluminum, titanium or nickel. The coating 125 can be produced using a sputtering process in combination with a lift-off process. Before the sputtering process, areas that are not to be provided with the coating 125, i.e. in this case areas in the region of the mating contacts 141, can be covered with a mask or photoresist mask. In the sputtering process, the coating 125 can be applied over a large area on the carrier plate 130 and the polymer material 120. Subsequently, by removing or dissolving the mask, the coating 125 in the region of the mating contacts 141 can be removed, so that the structure shown in Figure 29 is present (not shown).

[0107] Chip assembly then takes place, according to which radiation-emitting semiconductor chips 150 are mounted within the recesses 111 of the housing structure 110 on the mating contacts 141 of the conductor structure 140, as shown in Figure 30 from the side using a single semiconductor chip 150. Because the conductive coating 125 is omitted in the region of the mating contacts 141, there is no short circuit between the mating contacts 141 and thus contacts 151 of the semiconductor chips 150.

[0108] Subsequently, as shown in a side view in Figure 31, the reflective layer 170 is formed on the carrier 105 in the region of the mounting side 131. This process comprises the above-explained electrophoretic deposition of reflective particles 171, which in this case are deposited on the conductive coating 125 of the housing structure 110, partly on the connection contacts 142, and in the region of the connection points of the semiconductor chips 50 on the contacts 151, the connecting material 160 and the mating contacts 141. In this case, a corresponding electrical potential can be applied to the conductive coating 125 adjacent to the connection contacts 142 via the conductor structure 140 and the electrode plate 185 which is also used.After the electrophoretic deposition, the reflective layer 170 is stabilized by sintering the particles 171 or applying the transparent encapsulation material 175 as stated above.

[0109] Thereafter, as illustrated in Figure 32, a singulation process is carried out to provide separate radiation-emitting components 100. This is carried out by severing the carrier 105, including the reflective layer 170 present on the conductive coating 125, along dividing lines 211, so that the carrier 105 and thus its carrier plate 130 and the housing structure 110 are divided into individual smaller carriers 105, each associated with one of the components 100, said carriers having a carrier plate 130 and a housing structure 110 comprising only one cutout 111. The housing structure 110 of a singulated component 100 has a circumferential lateral outer side 114 which is not covered with the reflective layer 170.

[0110] In a component 100 manufactured according to the process sequence of Figures 29 to 32, the polymer material 120 can be protected by the conductive coating 125 together with the reflective layer 170 from the light radiation 200 generated by the semiconductor chip 150 during operation. The reflective layer 170 can provide a reflectivity or UVC reflectivity that is higher than the reflectivity achievable via the conductive coating 125 alone.

[0111] The method sequence of Figures 29 to 32 can be modified in a manner comparable to the method sequence of Figures 4 to 13 such that, after the application of the polymer material 120, separating trenches 210 are formed in the housing structure 110, which initially does not yet have a conductive coating 125, in regions between the connection contacts 142, so that the housing structure 110 is divided into individual, smaller housing structures 110 belonging to the components 100, each with a recess 111. Subsequently, the individual housing structures 110 can be provided with the conductive coating 125 in the manner described above, and by subsequently forming the reflective layer 170 followed by singulation, components 100 can be produced in which the outer sides 114 of the housing structures 110 are covered with the reflective layer 170.During the electrophoretic deposition carried out as part of the formation of the reflective layer 170, a corresponding electrical potential can be applied to the conductive coating 125 of the individual housing structures 110 via the conductor structure 140 of the carrier 105 (not shown).

[0112] A further modification of the process sequence of Figures 29 to 32 consists in applying the polymer material 120 of the housing structure 110 to the carrier plate 130 in a manner corresponding to the process sequence of Figures 25 to 27 by a process such as dispensing, spraying, or printing. As a result, the applied housing structure 110 can have a different, round cross-sectional profile corresponding to Figure 25.

[0113] In addition to the embodiments described above and illustrated in the figures, further embodiments are conceivable which may include further modifications and / or combinations of features.

[0114] For example, other materials can be used instead of the materials specified above. This can apply, for example, to the reflective particles 171. In this sense, it is also conceivable that the particles 171 are not negatively charged, but positively charged, due to activation. Accordingly, the electrophoretic deposition of such particles 171 can be carried out with inverse electrical potentials, in contrast to the above description, and thus with a reversal of the roles of anode and cathode.

[0115] Furthermore, other semiconductor chips can be used instead of the described radiation-emitting semiconductor chips 150. Such semiconductor chips can be designed, for example, to generate a different type of light radiation, for example, visible light radiation.

[0116] Furthermore, the housing structure 110 can be manufactured with other shapes and geometries, deviating from the cross-sectional and top view shapes shown in the figures. Although the invention has been illustrated and described in detail using preferred embodiments, the invention is not limited to the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

[0117] LIST OF REFERENCE SYMBOLS radiation-emitting component carrier housing structure recess inside front side outside polymer material base material conductive particles conductive coating carrier plate mounting side conductor structure mating contact connection contact through contact external contact radiation-emitting semiconductor chip contact radiation-generating area conductive connecting material reflective layer reflective particles encapsulation material power source anode cathode electrode plate electrode plate container coating bath preparation container suspension activation material light radiation dividing trench dividing line thermal energy

Claims

PATENT CLAIMS 1. A method for producing a radiation-emitting component (100) comprising: Providing a carrier (105) with a housing structure (110), wherein the housing structure (110) is formed from a polymer material (120) and has a recess (111); Arranging a radiation-emitting semiconductor chip (150) on the carrier (105) in the recess (111) of the housing structure (110); and Forming a reflective layer (170) at least on the housing structure (110), wherein the formation of the reflective layer (170) comprises electrophoretic deposition of reflective particles (171).

2. The method according to claim 1, wherein the semiconductor chip (150) is configured to generate UV radiation, and wherein the reflective layer (170) is UV-reflective.

3. The method according to any one of the preceding claims, wherein forming the reflective layer (170) comprises sintering the reflective particles (171) after electrophoretic deposition.

4. The method according to any one of the preceding claims, wherein forming the reflective layer (170) comprises applying a radiation-transmissive encapsulation material (175) after the electrophoretic deposition.

5. The method of claim 4, wherein the encapsulation material (175) is one of the following: Polysiloxane; at least partially fluorinated polysiloxane; fluoropolymer; oxide material; silicon oxide; aluminum oxide.

6. Method according to one of the preceding claims, wherein the reflective particles (171) are polymer particles.

7. Method according to one of the preceding claims, wherein the reflective particles (171) are particles of polytetrafluoroethylene.

8. The method according to any one of claims 1 to 5, wherein the reflective particles (171) are inorganic particles.

9. The method according to any one of claims 1 to 5 and 8, wherein the reflective particles (171) are the following particles or comprise a mixture of several different ones of the following particles: Particles of barium sulfate; particles of yttrium phosphate; particles of gadolinium phosphate.

10. The method according to any one of the preceding claims, wherein the carrier (105) comprises a carrier plate (130) with a conductor structure (140) on which the housing structure (110) is arranged.

11. The method according to any one of the preceding claims, wherein the polymer material (120) of the housing structure (110) is an intrinsically conductive polymer material.

12. The method according to any one of claims 1 to 10, wherein the polymer material (120) of the housing structure (110) is an extrinsically conductive polymer material.

13. The method according to any one of claims 1 to 10, wherein the housing structure (110) has an electrically conductive coating (125) arranged on the polymer material (120), on which the reflective layer (170) is formed.

14. The method according to any one of the preceding claims, wherein providing the carrier (105) comprises applying the polymer material (120) of the housing structure (110) by performing a molding process.

15. The method according to any one of claims 1 to 13, wherein providing the carrier (105) comprises applying the polymer material (120) to the housing structure (110) by performing one of the following processes: dispensing; spraying; printing.

16. The method according to any one of the preceding claims, wherein a plurality of radiation-emitting components (110) are produced by providing the housing structure (110) with a plurality of cutouts (111), arranging a plurality of semiconductor chips (150) on the carrier (105) in the cutouts (111), and separating into separate components (100) after the formation of the reflective layer (170).

17. The method according to claim 16, wherein prior to forming the reflective layer (170), separating trenches (210) are formed in the housing structure (110), so that the housing structure (110) can be divided into individual housing structures (110) with a recess (111) assigned to the respective components (100). wherein the reflective layer (170) is applied to the individual housing structures assigned to the components (110) (110) including in the region of the separating trenches (210), and wherein the separation comprises a severing in the region of the separating trenches (210).

18. Radiation-emitting component (100) comprising: a carrier (105) with a housing structure (110), wherein the housing structure (110) is made of a polymer material (120) and has a recess (111); a radiation-emitting semiconductor chip (150) arranged on the carrier (105) in the recess (111) of the housing structure (110); and a reflective layer (170) at least on the housing structure (110), wherein the reflective layer (170) comprises electrophoretically deposited reflective particles (171).

19. Component according to claim 18, wherein the reflective particles (171) are additionally sintered.

20. The component according to claim 18 or 19, wherein the reflective layer (170) comprises an encapsulation material (175).

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