DE102012203180A1 - Optoelectronic component and method for producing an optoelectronic component - Google Patents

Abstract

The present invention relates to an optoelectronic component comprising a carrier element (101), a semiconductor chip (102) mounted on the carrier element (101) and electrically contacted for emission of electromagnetic radiation, and a sedimentation element (200, 201, 202) arranged downstream of the semiconductor chip (102). 203, 204) comprising a binder (220) and a at least on the semiconductor chip (102) sedimented solid layer (210). The sedimentation element (200, 201, 202, 203, 204) has a decoupling surface (230, 233, 234) for decoupling the radiation emitted by the semiconductor chip (102), wherein the decoupling surface (230, 233, 234) curves and / or is structured. The present invention further relates to a method for producing an optoelectronic component.

Description

The present invention relates to an optoelectronic component, an arrangement comprising a carrier element, a semiconductor chip and a mask, and a method for producing an optoelectronic component.

In particular, the present invention relates to an optoelectronic component with a sedimentation element, which has a sedimented solid layer.

A non-exhaustive example of an optoelectronic component has an electrically contacted semiconductor chip for emitting electromagnetic radiation. For influencing the optical or thermal properties of the optoelectronic component, solids, for example phosphors, fillers, scattering particles or the like, are arranged in the beam path of the emitted radiation. A well-known concept here is sedimentation. Here, a suspension of a binder and the solid, which is present for example in the form of particles, applied to or in the vicinity of the semiconductor chip. Subsequently, the solid settles due to its higher density within the binder, which is referred to as sedimentation. By settling the solid, this gets closer to the semiconductor chip, which offers advantages in terms of thermal and optical properties. Subsequently, optical elements are still applied and the optoelectronic component can be installed depending on the purpose in modules or the like. The optoelectronic component is also referred to as an LED package.

The present invention is therefore based on the object to improve the known prior art.

Furthermore, it is an object of the present invention to provide an optoelectronic component, an arrangement of a carrier element, a semiconductor chip and a mask and a method for producing an optoelectronic component, so that the optoelectronic component is improved in terms of function and production.

This object is achieved by an optoelectronic component according to independent claim 1.

Furthermore, this object is achieved by an arrangement comprising a carrier element, a semiconductor chip and a mask according to independent claim 13.

Furthermore, this object is achieved by a method for producing an optoelectronic component according to independent claim 14.

Further developments and advantageous embodiments of the invention are specified in the dependent claims.

EXEMPLARY EMBODIMENTS

The present invention relates to an optoelectronic component comprising a carrier element, a semiconductor chip mounted on the carrier element and electrically contacted for emitting electromagnetic radiation, and a sedimentation element downstream of the semiconductor chip comprising a binder and a solid layer sedimented at least on the semiconductor chip, wherein the sedimentation element is a decoupling surface for decoupling the radiation emitted by the semiconductor chip, and wherein the outcoupling surface is curved and / or structured.

The optoelectronic component according to the invention is characterized in particular by improved optical and thermal properties and by a simplified production. So far, solids have been sedimented on the semiconductor chip in a plane and specially provided for the sedimentation layer. Subsequently, optical elements were applied. The disadvantage here is firstly the need to manufacture two elements separately. Furthermore, a part of the radiation is reflected by the transition between the layer for sedimentation and the optical element and thus does not escape from the optoelectronic component. The present invention utilizes a single element in a dual function by providing both for sedimentation and for decoupling the radiation. As a result, the mentioned losses are avoided in the transition between separate elements. Due to the special shape of the decoupling surface beyond total reflection is reduced or avoided altogether, so that the optoelectronic device has an overall increased efficiency. The reduction to an element and the special coupling-out surface thus cooperate in such a way that the efficiency of the optoelectronic component is increased. A central idea of the present invention is therefore the provision of a special decoupling surface in connection with the sedimentation process. Furthermore, it is ensured on the basis of the process of sedimentation that the optically and / or thermally active solid layer can be brought as close to the semiconductor chip, which for example due to the higher packing density the advantage of improved heat conduction or, depending on the type of solid, a Improved optical properties such as improved radiation (color over angle) or improved color homogeneity allows. Overall, the interaction of the individual features thus results in an optoelectronic component which has improved optical and thermal properties, in particular improvements in terms of efficiency.

In one embodiment, the decoupling surface is a second-order surface. By providing a decoupling surface having a second-order surface, a surface is provided by which the most effective total reflection can be minimized or avoided, thereby increasing the efficiency of the opto-electronic device.

In one embodiment, the decoupling surface has substantially the shape of a hemisphere or a semi-ellipsoid or a shape approximated to these shapes. The use of a hemisphere or half ellipsoid offers the same advantages as providing a second order surface. In addition, the hemisphere and hemi-ellipsoid provide a point-symmetrical or mirror-symmetrical Abtrahlcharakteristik.

In one embodiment, the following relation applies to the maximum height difference max (h _{P1, P2} ) between any two points P1 and P2 on the decoupling surface max (h _{P1, P2} ) ≥ 0.01 p, (1) where p is the maximum extent of the optoelectronic device. This relationship ensures that total reflection at the decoupling surface on the one hand is effectively avoided, on the other hand, the maximum possible flexibility in the shape of the decoupling surface is ensured.

In one embodiment, the decoupling surface is roughened. As a result, in principle, any desired basic shape can be selected for the sedimentation element, in which case the roughening in turn reduces or prevents total reflection. This allows greater flexibility in the selection of the sedimentation element and the manufacturing process. In particular, a flat sedimentation element can be provided, for example, thereby saving material as compared to, for example, a hemispherical sedimentation element and at the same time keeping the optoelectronic component compact. However, it is also possible to combine the roughening with one of the above-mentioned forms of decoupling surface.

In one embodiment, the decoupling surface has a microstructure, in particular microlenses or microprisms. By providing a regular and repetitive microstructure, total reflection can be reduced or prevented particularly well, which increases the efficiency of the optoelectronic component.

The semiconductor chip is preferably located within a circumference of the outcoupling surface projected onto the carrier element, and it applies d ≥ c, (2), particularly preferred d = 2c, (3), where d is the maximum diameter of the projected perimeter and c is the length of the diagonal of the semiconductor chip. This ensures that the entire radiation emitted by the semiconductor chip enters the sedimentation element and is decoupled from the sedimentation element via the decoupling surface. In particular, the preferred relation d = 2c on the one hand achieves a secure coupling-out of the radiation emitted by the semiconductor chip via the coupling-out surface, on the other hand the dimensions of the optoelectronic component are kept compact.

In one embodiment, the binder has a refractive index that is lower than the refractive index of the semiconductor chip and higher than the refractive index of air. As a result, a gradual transition of the refractive indices of the semiconductor chip to air is achieved, which in turn minimizes total reflection and thus overall improves the optical properties, in particular the efficiency, of the optoelectronic component.

Preferably, the binder is a silicone, polysilane, siloxane, polysiloxane, epoxide, polysilazane or a mixture thereof. The materials mentioned are characterized by easy processability, long durability and very good optical properties. Furthermore, all the materials mentioned have a refractive index which is lower than the refractive index of the semiconductor chip and higher than the refractive index of air, resulting in the advantages already mentioned.

In one embodiment, the optoelectronic component further comprises an optical element arranged downstream of the sedimentation element, in particular a lens.

The optical element preferably bears against the sedimentation element in a form-fitting manner and has a refractive index which is greater than the refractive index of air and less than the refractive index of the sedimentation element. The seamless joining of optical element and Sedimentationselement in combination with the specially selected refractive index of the transition between the refractive indices of semiconductor chip and air is further graduated, which in turn total reflection is reduced. By means of the positive engagement it is avoided that there is another material with a refractive index between the optical element and the sedimentation element, through which the gradual transition could be disturbed.

The solid layer preferably comprises at least one phosphor, at least one heat-conducting filler, scattering particles or a mixture thereof. Depending on the type of solid used, the properties of the optoelectronic component can advantageously be changed. Particularly in the case of the use of light-converting phosphors, the method of application and arrangement of the converter within the optoelectronic component is decisive with regard to the optical and thermal properties, the efficiency, the cost and the service life of the optoelectronic component. When using phosphors as a sedimented solid layer, the phosphor reaches closer to the semiconductor chip, whereby the thermal cooling of the phosphor is improved. The thermal cooling is again improved by the higher packing density, which leads to a higher specific thermal conductivity of the material. Furthermore, by the thus achieved complete and uniform enveloping the semiconductor chip (English "conformal coating") optimized radiation (color over angle) is achieved. By using scattering particles, the color homogeneity with respect to the emission angle can be improved. By heat-conductive fillers, furthermore, an improvement in the thermal conductivity can be achieved.

The present invention furthermore relates to an arrangement comprising a carrier element, a semiconductor chip and a mask, comprising a carrier element, a semiconductor chip mounted on the carrier element and electrically contacted for emission of electromagnetic radiation, and a mask with a recess enclosing the semiconductor chip for receiving a shape to be formed Basic mass, wherein the semiconductor chip facing surface of the recess is curved and / or structured.

The inventive arrangement makes it possible to produce the optoelectronic component according to the invention with the advantages already mentioned. The decoupling surface can be formed by the mask for forming the matrix for the sedimentation element, at the same time the matrix can be stabilized long enough in liquid form to allow sedimentation with the advantages already mentioned.

The present invention furthermore relates to a method for producing an optoelectronic component, comprising the steps of providing a semiconductor chip mounted and electrically contacted on a carrier element for emission of electromagnetic radiation, applying a matrix comprising a binder matrix and solid particles at least to the semiconductor chip and simultaneously forming the matrix, Sedimentation of the solid particles to a solid layer at least on the semiconductor chip, and curing the matrix to a sedimentation, wherein the sedimentation has a decoupling surface for decoupling emitted from the semiconductor chip radiation, and wherein the step of forming comprises forming the decoupling surface, so that the decoupling surface curved and / or structured.

The combination of sedimentation and forms of the decoupling surface in one element, the manufacturing process is simplified, since only one step for forming decoupling element and sedimentation of the solid layer must be provided. The sedimentation process step also simplifies the application of the solid layer and the semiconductor chip is completely covered by the solid layer, which offers the advantages already mentioned, depending on the type of solid used. In other words, the sedimented solid layer and the decoupling element can be produced in one process step, which offers the advantage of cost savings.

Preferably, the step of forming comprises the provision of a mask, in particular the provision of a mask with a recess surrounding the semiconductor chip, wherein the surface of the recess facing the semiconductor chip is curved and / or structured. By providing a mask, the steps of sedimentation and molding can be effectively accomplished in one step, thereby making the manufacturing process more efficient, less expensive and easier.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the solution according to the invention are explained in more detail below with reference to the drawings. In the figures, the first digit (s) of a reference numeral indicate the figure in which the numeral is used first. The same reference numbers are used for similar or equivalent elements or properties used in all figures.

Show it

1 a schematic representation of a cross section of an optoelectronic component according to the invention according to a first embodiment,

2 a schematic representation of a cross section of an optoelectronic component according to the invention according to a second embodiment,

3 a schematic representation of a cross section of an optoelectronic component according to the invention according to a third embodiment,

4 a second schematic representation of a cross section of the optoelectronic component according to the invention according to the first embodiment,

5 a schematic representation of a plan view of the optoelectronic component according to the invention according to the first embodiment,

6 a schematic representation of a cross section of an optoelectronic component according to the invention according to a fourth embodiment,

7 a schematic representation of a cross section of an optoelectronic component according to the invention according to a fifth embodiment,

8th a schematic representation of a cross section of an optoelectronic component according to the invention according to a sixth embodiment,

9a FIG. 2 a schematic representation of a bottom view of a mask for forming a sedimentation element for the optoelectronic component according to the invention, FIG.

9b a schematic representation of a cross section of the mask according to 9a .

9c a schematic representation of a plan view of the mask according to 9a .

10a to 10d a schematic representation of a cross section of an inventive arrangement of carrier element, semiconductor chip and mask during various process steps of the manufacturing method according to the invention, and

11 a flow chart with the process steps of the manufacturing method according to the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

1 shows a schematic representation of a cross section of an optoelectronic component according to the invention 100 according to a first embodiment.

On a support element 101 is a semiconductor chip 102 assembled. At the semiconductor chip 102 it is an optoelectronic semiconductor chip 102 For example, a light emitting diode, OLED or another opto-electronic element that emits or absorbs electromagnetic radiation. The semiconductor chip 102 For example, it may be formed on a semiconductor substrate by a layer sequence generated in a semiconductor process. The semiconductor chip 102 may also have been made by a thin film process. The semiconductor chip 102 can also be substrateless. He has a contact page 104 on, with which he is on the support element 101 by means of known methods (LED attaches) is applied, and over which it has at least one electrical contact. It is conceivable that also a further electrical contact via the contact side to the support element 101 connected. However, any other type of contacting the semiconductor chip is 102 conceivable.

The carrier element 101 may be a leadframe or a substrate, depending on the type of optoelectronic device to be fabricated. It serves, for example, for the mechanical stabilization of the optoelectronic component and / or for the electrical connection of the semiconductor chip 102 with external electrical contacts. The carrier element 101 For example, it may be a ceramic carrier or a semiconductor carrier.

On the contact page 104 opposite side, the semiconductor chip 102 a radiation emission side 108 on. About the radiation emission side 108 becomes one in the semiconductor chip 102 generate radiation decoupled. In order to achieve the most efficient decoupling of the generated radiation, the carrier element 101 a reflective surface, for example a silver coating in the region of the contact side 104 exhibit.

A sedimentation element 200 is the semiconductor chip 102 downstream. That is, the sedimentation element 200 is on the Radiation emission side 108 or in other words provided in the emission direction. The sedimentation element 200 has a binder 220 and a solid layer sedimented in the binder 210 on.

As already explained, sedimentation is a well-known concept. In this case, a suspension of a binder base material and the solid, which is present for example in the form of particles, on the semiconductor chip 102 applied. Subsequently, the solid is due to its higher density within the binder base as a solid layer 210 from what is called sedimentation. By depositing the solid, this gets closer to the semiconductor chip 102 as without sedimentation, which offers various advantages depending on the type of solid used. Particularly when using light-converting phosphors, the method of application and arrangement of the converter within the optoelectronic component is decisive with regard to the optical and thermal properties, the efficiency, the costs and the service life of the optoelectronic component. When using phosphors as a sedimented solid layer, the phosphor reaches closer to the semiconductor chip, whereby the thermal cooling of the phosphor is improved. The thermal cooling is again improved by the higher packing density, which leads to a higher specific thermal conductivity of the material. Furthermore, by the thus achieved complete and uniform enveloping the semiconductor chip (English "conformal coating") optimized radiation (color over angle) is achieved. By using scattering particles, the color homogeneity with respect to the emission angle can be improved. By heat-conductive fillers, furthermore, an improvement in the thermal conductivity can be achieved.

The solid layer 210 is at least on or along the semiconductor chip 102 sedimented. Depending on the shape and dimensions of the sedimentation element 200 and after the construction of the optoelectronic component 100 can the solid layer 210 be sedimented on other components, for example on the support element 101 , on a conductor connection (not shown) or on one or more other components of the optoelectronic component 100 ,

The sedimentation element 200 is thus the result of the sedimentation and comprises the resulting from the binder base binder 220 as well as the sedimented solid layer 210 , which in this embodiment in direct contact with the semiconductor chip 102 stands. The sedimentation process and the materials used will be explained in more detail later. By using sedimentation, there is no interface between the clear area, ie the binder 220 , and the sedimented solid layer 210 to recognize. This distinguishes the sedimentation from other processes in which the decoupling element is manufactured and applied separately from the solid layer, where an interface is recognizable due to the subsequent application. Furthermore, it is possible that isolated sedimented solid particles in the clear area, especially in the transition region, are still present when using the sedimentation. This is also not the case in the case of a subsequently applied decoupling element. Overall, it is thus possible in the absence of an interface and in the presence of individual unsedimentierter particles on the finished sedimentation 200 recognize that it has been produced by sedimentation and not by other methods.

The sedimentation element 200 has a decoupling surface 230 for decoupling the from the semiconductor chip 102 emitted radiation from the sedimentation 200 , In other words, the decoupling surface 230 that side or surface of the sedimentation element 200 , by which essentially the radiation from the sedimentation element 200 exit. The decoupling surface is thus that of the semiconductor chip 102 opposite surface of the sedimentation 200 , The sedimentation element 200 has in the first embodiment according to 1 also a side surface 240 on, which directly to the decoupling surface 230 connects and emerges from the no or only a negligible part of the radiation. The side surface 240 is preferably perpendicular to the plane of the semiconductor chip 102 but may also have an angle different from 90 ° with the plane of the semiconductor chip 102 lock in. Under decoupling surface 230 should therefore a the semiconductor chip 102 opposite surface of the sedimentation 200 along which or through which the entire or at least the essential part of the sedimentation element 200 emerging radiation emerges.

According to the present invention, the decoupling surface 230 curved and / or structured. The decoupling surface 230 is therefore not plan, but rather has a curvature, a structuring or both. This ensures that the radiation from the chip on the decoupling surface 230 impinges at an angle of approximately 90 °, so that total reflection can be avoided or at least reduced. The structuring can be provided in particular in the areas in which the risk for total reflection is increased. The further away from the center of the sedimentation element the radiation strikes the outcoupling surface, the higher the probability of total reflection. Therefore, can either the entire outcoupling surface or only the edge region of the decoupling surface be structured. That is, by a curved and / or structured decoupling surface 230 is at the exit of the radiation from the sedimentation 200 the total reflection is reduced, so that a higher proportion of the radiation from the sedimentation 200 leakage and thereby the efficiency of the optoelectronic device 100 is increased.

A central idea of the present invention is therefore the combination of the sedimentation step or of the element required for sedimentation with a coupling-out structure. Both elements or steps are thus combined in the sedimentation with the decoupling surface according to the invention. The sedimentation element can furthermore be produced in only one process step. In addition, the benefits of sedimentation can be exploited. Overall, the inventive combination of sedimentation and decoupling surface in one element or in a manufacturing step gives a synergistic effect, so that the present invention provides a simplified and less expensive production method and an optoelectronic component, which improves in terms of its optical and thermal properties, in particular in terms of its efficiency is.

In the optoelectronic component 100 according to the first embodiment has the decoupling surface 230 as in 1 represented essentially the shape of a hemisphere.

2 shows a schematic representation of a cross section of an optoelectronic component according to the invention 110 according to a second embodiment. Unless otherwise described, all explanations made for the first embodiment also apply to the second embodiment.

The sedimentation element 201 of the optoelectronic component according to the second embodiment has, after the decoupling surface 230 a page element 241 on, which is from the end of the decoupling surface 230 from the semiconductor chip 102 away in the lateral direction along the carrier element 101 extends. Lateral means in particular along main directions of extension of the semiconductor chip 102 or of the carrier element 101 , In other words, it is the decoupling surface 230 , seen in plan view, from the side member 241 bordered, in particular with a uniform width. Through the side element 241 is due to the larger contact surface of the sedimentation 230 a better adhesion between the sedimentation element 230 and the semiconductor chip 102 or the carrier element 101 guaranteed.

3 shows a schematic representation of a cross section of an optoelectronic component according to the invention 120 according to a third embodiment. Unless otherwise described, all explanations made for the first embodiment also apply to the third embodiment.

In this embodiment, the semiconductor chip 102 laterally or in the lateral direction of a potting compound 300 envelops. Preferably, the potting compound 300 the same height as the semiconductor chip 102 and thus closes flush with the radiation emission side 108 of the semiconductor chip 102 so that the sedimentation element 202 is applied to a flat surface, which is the application of the sedimentation 202 simplified. In the potting compound 300 Reflective particles or scattering particles can be integrated, for example metal oxides, so that laterally out of the semiconductor chip 102 emerging radiation is reflected and along the main emission from the semiconductor chip 102 exit. This also improves the efficiency of the optoelectronic component 120 elevated.

In the optoelectronic component 120 according to the in 3 shown third embodiment, the decoupling surface closes 230 directly to the potting compound 300 and it is not a side surface 240 or page element 241 intended. Alternatively, the potting compound 300 also be combined with the first or second embodiment and the side surface 240 or the page element 241 can on the potting compound 300 rest or connect to them. The potting compound 300 may also be lower or higher than the semiconductor chip 102 ,

As already explained, the core idea of the present invention is to provide a decoupling surface in connection with sedimentation, which is curved and / or structured. The curvature or structuring can also be provided only on parts of the decoupling surface. For example, it may not be possible for production-technical reasons to provide the entire decoupling surface with a curvature and / or structure throughout, and areas may remain un-curved or unstructured. Certain areas may also intentionally remain un-curved or unstructured, for example to facilitate detachment of a forming tool. Such a decoupling surface is nevertheless encompassed by the present invention. Preferably, the curvature and / or structure extends over a large part of the decoupling surface. It is preferred those areas with a curvature and / or a Structuring structured in which at least part of the radiation at an angle greater than the total reflection angle impinges (in each case measured to the solder on the exit surface). The critical total reflection angle (measured perpendicular to the exit surface) is given by Tc = arcsin (n_2) / n_1), where n_1 and n_2 are each the refractive index of the outer and inner materials. In general, n_2> n_1. For example, with a decoupling of silicone (n = 1.41) from air (n ~ 1), this angle is about 45 °. When coupling a silicone with n = 1.53 into a silicone with n = 1.41, the total reflection angle is about 67 ° to the solder. In a preferred embodiment (in order to achieve a shaping of the emission characteristic in addition to the improved decoupling), at least 70% of the exit surface is curved or patterned, preferably at least 80%, particularly preferably at least 90% of the exit surface.

In the following, the feature of the curvature will be discussed in more detail. Under curvature should first be understood any curvature of the decoupling surface through which the decoupling surface is no longer completely flat or flat.

In particular, the decoupling surface is at least in sections a second-order surface. For example, the decoupling surface may have a hemisphere, a semi-ellipsoid or a shape approximated to these shapes. In particular, the decoupling surface can be partially approximated to different shapes and the radius of curvature of the decoupling surface can be constant or variable over the entire surface.

Referring to 4 In the following, an alternative definition for the curvature of the decoupling surface is explained in more detail. 4 again shows a schematic representation of a cross section of the optoelectronic component 100 according to the first embodiment.

The maximum extent of the optoelectronic component 100 is denoted by p. In this case, maximum expansion is understood to mean an expansion in the lateral direction. Under curvature of the decoupling surface 230 According to this definition, the condition should be understood according to which for any two points P1 and P2 on the decoupling surface 230 the maximum height difference h between these two points satisfies the following relation: max (h _{P1, P2} ) ≥ 0.01 p, (1) where max (h _{P1, P2} ) represents the already explained maximum height difference. As a result, the curvature depends on the extent of the optoelectronic component 100 , whereby it is ensured that for each size of the optoelectronic component 100 the decoupling surface 230 is curved so that total reflection is avoided and the efficiency of the optoelectronic device 100 is increased.

Although this relation has been described by way of example with reference to the first embodiment, the relation is not limited to the first embodiment, but is applicable to any other embodiment. As already explained, this relation can only apply in sections for the decoupling surface.

5 shows a schematic representation of a plan view of the optoelectronic component according to the invention 100 according to the first embodiment. On the basis of this plan view, the preferred size ratios between the semiconductor chip 102 and the sedimentation element 200 to be discribed. A on the support element 101 projected scope 209 the decoupling surface 230 is shown circular in this embodiment. The scope 209 in other words, the maximum lateral extent of the decoupling surface 230 The circumference thus does not represent the maximum lateral extent of the entire sedimentation element 200 but only the maximum lateral extent of the decoupling surface 230 in plan view. In the case of the hemispherical decoupling surface 230 is the scope 209 circular, depending on the shape of the decoupling surface, the scope 209 but also have any other shape.

In the 5 is the maximum diameter d of the circumference 209 represented as well as the length c of the diagonal of the semiconductor chip 102 , Preferably, the semiconductor chip is located 102 completely within the decoupling surface 230 ie the relation holds d ≥ c (2)

This has the advantage that essentially the entire of the semiconductor chip 102 over the radiation emission side 108 emitted radiation, the sedimentation 200 through the decoupling surface 230 leaves. As a result, high efficiency of the optoelectronic component is again achieved.

Preferably, the decoupling surface 230 a diameter which is twice the diagonal of the diagonal, ie the relation holds d = 2c (3)

As a result, on the one hand total reflection, for example, in the edge region of the decoupling surface 230 , further reduced, on the other hand still a compact size of the optoelectronic device is guaranteed.

In the case of a decoupling surface 230 , which has the shape of a hemisphere, d corresponds to the diameter of the ball.

Although the size ratios have been described by way of example with reference to the first embodiment, the description is not limited to the first embodiment, but rather applicable to any other embodiment and not shown Auskoppelflächen.

Preferably, according to the present invention, the total reflection or the radiation losses are further reduced by appropriate choice of material, so that a gradual refractive index transition from the semiconductor chip 102 to the air becomes possible. The refractive index of the semiconductor chip 102 , ie in particular the radiation emission side comprising the epi-layer 108 , is very high relative to the refractive index of air. The sedimentation element 200 which is between the semiconductor chip 102 and the air is provided, therefore, ideally has a refractive index which is lower than the refractive index of the semiconductor chip 102 but higher than the refractive index of air, so that a gradual transition between the refractive indices is achieved, thereby further reducing total reflection. In particular, we the refractive index of the sedimentation element 200 chosen as large as possible within the scope of the possible materials, so that it adhere to the refractive index of the semiconductor chip 102 approaches. The refractive index of the sedimentation element is preferably 200 therefore in the range 1.40 to 1.54. The material used is preferably silicone. In particular, for example, a so-called LRI silicone can be used (LRI = low refractive index, ie English for low refractive index) with a refractive index of about 1.41. Non-exhaustive examples of such LRI silicones are methyl-substituted silicones. LRI silicones have the advantage that they are inexpensive and mechanically robust, so they have a long life. It can also be a so-called HRI silicone are used (HRI = high refractive index, ie English for high refractive index) with a refractive index of 1.41 to 1.57, depending on the degree of phenylation. Non-exhaustive examples of such HRI silicones are phenyl-substituted silicones. HRI silicones have the advantage of a very low loss of brightness in the optoelectronic component. Instead of silicone, it is also possible to use epoxides having a refractive index of about 1.5 or polysilazanes having a refractive index of about 1.46.

6 shows a schematic representation of a cross section of an optoelectronic component according to the invention 150 according to a fourth embodiment. The optoelectronic component 150 corresponds to the optoelectronic component 100 according to the first embodiment in 1 , only is in the optoelectronic device 150 according to the fourth embodiment still an optical element 310 intended. Preferably, the optical element 310 a lens or coupling lens.

The optical element 310 is the sedimentation element 200 downstream in the emission direction. As in 6 represented, lies the optical element 310 preferably flush with the decoupling surface 230 on, ie is in direct contact with the decoupling surface 230 , However, it is also conceivable that between the optical element 310 and the decoupling surface 230 partially or completely there is a gap.

The optical element 310 can also rest flush on other components, for example, on the side surface 240 and on the carrier element 101 , The optical element is preferably produced by means of injection molding in a separate step and then into the optoelectronic component 150 integrated.

Preferably, the optical element consists 310 of a material having a refractive index greater than the refractive index of air and less than the refractive index of the sedimentation element 200 , As a result, the refractive index transition from the semiconductor chip 102 further graduated to air, so that is further reduced by the gradation of the refractive index jump and thus total reflection.

7 shows a schematic representation of a cross section of an optoelectronic component according to the invention 130 according to a fifth embodiment. Unless otherwise described, all explanations made for the first embodiment also apply to the fifth embodiment.

In contrast to the exemplary embodiments described so far, in which the sedimentation element comprises a curved or curved outcoupling surface, the sedimentation element has 203 of the optoelectronic component 130 a roughened decoupling surface 233 on, like in 7 shown schematically.

By roughening is also achieved again that total reflection when hitting the semiconductor chip 102 emitted radiation on the decoupling surface 233 is reduced or prevented. As a result, the efficiency of the optoelectronic component 130 be increased. The main extension direction of the roughened decoupling surface 233 is in this case parallel to the semiconductor chip 102 respectively. to the carrier element 101 , Unlike in 7 shown, the main extension direction of the roughened decoupling surface 233 however, it may follow a different shape, for example it may be curved or arched. In other words, a curvature of the decoupling surface can be combined with a roughening.

• (a) der fertigen Linse oder
• (b) des Werkzeugs oder
• (c) einer Folie (welche sich zwischen Werkzeug und

The roughening can be achieved, for example, by an etching process or by mechanical removal. The roughening depth depends on the process selected and can be selected in the range of 2 μm (for example, in the case of chemical roughening) up to 250 μm (for example in the case of sandblasting). This roughening can be done both by roughening

• (a) the finished lens or
• (b) the tool or
• (c) a foil (which is between tool and

Silicone body is located. The processes (a) to (c) may be used singly or in combination. The relation, according to which the d ≥ 40 · T, (4) where d as already explained, the diameter of the decoupling surface 230 and T is the roughness depth.

8th shows a schematic representation of a cross section of an optoelectronic component according to the invention 130 according to a sixth embodiment. Unless otherwise described, all explanations made for the first embodiment also apply to the sixth embodiment.

The sedimentation element 204 of the optoelectronic component 140 has a coupling surface provided with microlenses 234 on, like in 8th shown schematically. Alternatively, microprisms, other microstructures or a moth-eye structure may be used. The decoupling surface 234 thus has a plurality of miniaturized lenses and / or prisms, by which in turn total reflection is reduced or prevented.

The main direction of extension of the micro-lensed decoupling surface 234 is in this case parallel to the semiconductor chip 102 or to the carrier element 101 , Unlike in 8th shown, the main extension direction of the microlensed decoupling surface 233 however, it may follow a different shape, for example it may be curved or arched. In other words, a curvature of the decoupling surface can be combined with microlenses, microprisms or a moth-eye structure.

Referring to the 9a to 9c Now, a mask will be described, which can be used in the production of the optoelectronic component according to the invention.

9a 1 shows a schematic illustration of a bottom view of a mask for forming a sedimentation element for the optoelectronic component according to the invention, 9b a schematic representation of a cross section of the mask according to 9a and 9c a schematic representation of a plan view of the mask according to 9a , Here, by way of example, a mask for producing a sedimentation element 202 for an optoelectronic component 120 according to the third embodiment, but the principle can be applied to the production of each sedimentation element.

The mask 400 has at least one recess 410 on. The recess 410 hereby forms a mold for the sedimentation element to be formed 200 In the present case, the recess has 410 hence the shape of a hemisphere corresponding to the sedimentation element 202 out 3 , Preferably, the mask comprises 400 several recesses 410 which are arranged so that through each recess 410 a sedimentation element 202 on a semiconductor chip 102 can be formed. In other words, the recesses are 410 corresponding to the semiconductor chips 102 arranged on a support element.

A surface 430 the recess 410 is shaped according to the decoupling surface to be reached. In the present example, the surface has 430 a hemispherical shape, so that the sedimentation element formed 202 corresponding to a substantially hemispherical decoupling surface 230 Has. Alternatively, depending on the desired decoupling surface, the surface 430 variously curved, structured or both. All for the decoupling surface 230 made statements thus apply in an analogous manner for the surface 430 the recesses 410 , It can be in a mask 400 also recesses 410 with different surfaces 430 be provided.

Preferably, the mask 400 at the top of each one opening 430 in the area of each recess 410 on. As a result, the material for the sedimentation through the opening 420 into the recess 410 be introduced.

The mask 400 is here preferably made of, for example spring steel, coated steel, coated metal, Teflon, coated plastic or polyetheretherketone (PEEK). In an alternative embodiment, the mask may also be formed without an opening, and accordingly the production method of the optoelectronic component must be adapted accordingly.

10a to 10d show a schematic representation of a cross section of an arrangement according to the invention 500 from carrier element, semiconductor chip and mask during different process steps of the manufacturing method according to the invention. Here, by way of example, the production of a sedimentation element 200 an optoelectronic component 120 is described according to the third embodiment, however, is for simplicity in the 10a to 10d the potting compound 300 omitted.

10a shows a provided carrier element 101 with a semiconductor chip applied and electrically contacted thereon 102 , Other components (such as tracks) are not shown in the figures for simplicity.

The mask 400 is on the carrier element 101 put on so that the recess 410 the semiconductor chip 102 surrounds or encloses. In the preferred embodiments, as already explained, the diameter of the circumference 109 the decoupling surface 230 at least as large as the chip diagonal, so that the semiconductor chip 102 completely within the scope 109 the decoupling surface 230 lies. In this case, the mask lies on the carrier element 101 or on a possibly provided potting compound 300 on. The opening 420 lies here on the semiconductor chip 102 opposite side of the mask 400 ,

In 10a is an example of an arrangement 500 from semiconductor chip 102 , Carrier element 101 and mask 400 shown in which the mask 400 only one recess 410 Has. Alternatively, multiple semiconductor chips 102 be arranged side by side or in a matrix and the mask 400 according to several recesses 410 comprising the multiple semiconductor chip 102 encloses.

As in 10b shown, then becomes a matrix 250 for the sedimentation element to be produced 203 through the opening 420 into the recess 410 introduced, for example by means of a dispensing process (English Dispensing).

The basic mass 250 comprises a binder base 225 and a solid, preferably in the form of solid particles 215 , The solid particles 225 are here in the binder base 225 dispersed.

As binder base 225 For example, a silicone is preferably used. In particular, a polysilane, siloxane and / or polysiloxane can be used as the material. Alternatively, an epoxide or polysilazane can be used. When introducing the basic mass 250 into the recess 410 is the binder base 225 not fully cured and / or not fully crosslinked. In particular, the binder base is 225 flowable or deformable. The curing or crosslinking of the binder base 225 is carried out by known methods, for example thermally, by UV radiation and / or by other methods.

The solid particles 215 may include thermally and / or optically active solids. For example, the solid particles 215 a material for improving the thermal conductivity, which is optically inactive and transparent, for example, SiO ₂ . Another possibility is the use of diffusely scattering particles to improve the color homogeneity with respect to the emission angle. Examples of these are reflective particles and / or scattering particles, in particular metal oxides such as titanium oxide, aluminum oxide, zinc oxide, zirconium oxide or silicon oxide, and barium sulfate, dyes, organic fillers or mixtures thereof.

Another possibility is the use of Leuchststoffpartikel. The phosphor particles may contain one or more phosphor types. The phosphor or the plurality of phosphors are adapted to that of the semiconductor chip 102 emitted electromagnetic radiation from a first wavelength range to at least partially absorb and to convert radiation into a second wavelength range, which is different from the first wavelength range. For example, the phosphor particles are designed to absorb radiation in a wavelength range between 420 nm and 490 nm inclusive and convert it to longer wavelength radiation. That is, the phosphor can convert, for example, blue light into greenish, yellowish and / or reddish light. Non-limiting examples of phosphor particles is a rare earth doped garnet such as YAG: Ce, a rare earth doped orthosilicate such as (Ba, Sr) ₂ SiO ₄ : Eu, or a rare earth doped silicon oxynitride or silicon nitride such as (Ba, Sr) ₂ Si ₅ N ₈ : Eu. These phosphors are given only as illustrative examples, and the present invention is not limited to the phosphors mentioned, but rather includes the use of said phosphors as well as any other phosphors, alone or in combination. The advantages of the process of sedimentation in the application of the phosphor have already been explained.

The solid particles 215 may also comprise a mixture of the above materials. The particle size can vary between d50 = 2μm and d50 = 20μm. The proportion of solid particles 215 and the basic mass 250 can also vary widely, for example, when using phosphor particles, the proportion depends on the desired color location. Preferably, a proportion of the solid particles 215 at the ground 250 between 7% wt and 15% wt.

10c shows the arrangement 500 after the introduction of the basic mass 250 during the sedimentation process. Preferably, the recess 410 complete with matrix 250 filled. The solid particles 215 settled within the binder matrix due to their higher density 225 from. This process can be done solely by using gravity, ie at rest, but it can also be accelerated. For example, the process can be done in a centrifuge. Alternatively or additionally, the process can also be potential-controlled, in which case sedimentation takes place within an electric field. Another possibility is the temperature control of the sedimentation process, in which the curing or crosslinking of the binder base mass via a temperature regulation 225 slows down, causing the sedimentation of the solid particles 215 can be done faster. The methods mentioned can also be used in combination.

There is also the possibility, in the case of the use of phosphors, through the opening 420 carry out an inline control of the color location and if necessary further phosphor particles through the opening 420 if the measured color location deviates from the desired color location.

10d shows schematically the arrangement 500 after sedimentation of the solid particles 215 to the solid layer 210 and with fully cured or crosslinked binder 220 , For the completion of the optoelectronic device only has the mask 400 be removed. For this purpose, it is advantageous if the decoupling surface 203 partially flattened, so that the mask 400 can be easily replaced.

It should be noted that the illustration in 10d as well as not have to be true to scale in the other embodiments. The solid particles 215 can be shown enlarged or reduced in relation to the optoelectronic component, can thus have any size. Also in the figures is the solid layer 210 from only one layer of solid particles 215 shown, which serves only the simplified representation. Notwithstanding the figures, several layers of solid particles 215 be provided, the solid layer 210 especially within the solid layer 210 variable thicknesses, ie at different points a different number of layers of solid particles 215 exhibit. Also, unlike the figures, preferably, there are no voids in the solid layer 210 so that the solid layer 210 the semiconductor chip 102 completely covered.

Because of the opening 420 is the decoupling surface 230 at least in the area of the opening 420 hardly or not curved and not structured. However, since the opening is in the range of a radiation angle of substantially 0 °, occurs at this point little or no total reflection, so that a lack of curvature or structuring here hardly matters.

An alternative manufacturing method, which is not shown in the figures, sees a mask 400 without opening 420 before, ie the recesses 410 are closed at the top. This is the basic mass 250 in the recesses 410 introduced, then the support element 101 with the chip 102 placed over the head on the mask, leaving the semiconductor chip 102 into the matrix 250 dips or rests against this. Subsequently, the entire arrangement 500 turned around, so that then the sedimentation process can proceed. The advantage of this mask and the associated method is that the entire decoupling surface through the surface 430 the recess 410 can be formed because no opening is provided.

Referring to 11 The method steps of the manufacturing method according to the invention are explained below.

The method begins in a first step S0. In step S1 becomes a carrier element 101 with a semiconductor chip mounted thereon and electrically contacted 102 provided.

Subsequently, two alternative processes can be provided.

According to the first alternative, a mask is formed in a step S2 400 with a semiconductor chip 102 enclosing recess 410 and an opening 420 attached, wherein the semiconductor chip 102 facing surface 430 the recess 410 curved and / or structured. In the following step S3 becomes a matrix 250 comprising a binder base 225 and solid particles 215 through the opening 420 into the recess 410 brought in.

According to the second alternative, a mask is formed in a step S4 400 with a recess 410 and a curved and / or textured surface 430 the recess 410 provided. in the The following step S5 becomes a basic mass 250 comprising a binder base 225 and solid particles 215 into the recess 410 brought in. Subsequently, in step S6, the carrier element 101 with the semiconductor chip 102 on the mask 400 placed so that the semiconductor chip 102 in contact with the matrix 250 comes. The semiconductor chip 102 becomes, so to speak, the basic mass 205 immersed. In the following step, the arrangement of carrier element 101 , Semiconductor chip 102 and with groundmass 250 filled mask 400 turned around so that, the mask 400 on the semiconductor chip 102 or on the carrier element 101 is up and not the other way around.

Regardless of the alternatives just mentioned, in each case step S8 follows, in which the solid particles 215 to a solid layer 210 at least along the semiconductor chip 102 be sedimented. By the recess 410 through the groundmass 250 is filled, which takes the semiconductor chip 102 remote surface of the matrix 250 the shape and / or structure of the surface 430 the recess 410 at. In case of an opening 420 in the mask, this part remains the surface of the matrix 250 unstructured or unshaped. The present method therefore includes a step of molding the matrix 250 such that the the semiconductor chip 102 opposite side of the matrix 250 , which later forms the decoupling surface, curved and / or structured. Preferably, molding is accomplished by providing a mask 400 However, other ways of molding are also included in the present invention.

In the following step S9, the basic mass 250 cured or completely crosslinked us thus the sedimentation 200 formed, which has a decoupling surface in the form and / or structure of the surface 430 the recess 410 equivalent.

In the next step S10, the mask becomes 400 away. The process ends in step S11.

FINAL FINDING

The optoelectronic component and the method for producing an optoelectronic component have been described to illustrate the underlying idea based on some embodiments. The embodiments are not limited to specific feature combinations. Although some features and configurations have been described only in connection with a particular embodiment or individual embodiments, they may each be combined with other features from other embodiments. It is also possible to omit or add in individual embodiments illustrated features or particular embodiments, as far as the general technical teaching is realized.

Although the steps of the method of fabricating an optoelectronic device are described in a particular order, it is to be understood that any of the methods described in this disclosure may be performed in any other meaningful order, including but not limited to, method steps. unless deviated from the basic idea of the technical teaching described.

It is according to the present invention, a method for producing an optoelectronic device specified.

For example, one of many possibilities for producing the optoelectronic component described here can be realized by means of the method described here. This means that all features described for the optoelectronic component are also disclosed for the method and vice versa.

LIST OF REFERENCE NUMBERS

100

 Optoelectronic component according to a first embodiment

101

 support element

102

 Semiconductor chip

104

 Contact

108

 Radiation emission side

110

 Optoelectronic component according to a second embodiment

120

 Optoelectronic component according to a third embodiment

130

 Optoelectronic component according to a fifth embodiment

140

 Optoelectronic component according to a sixth embodiment

150

 Optoelectronic component according to a fourth embodiment

200

Sedimentation element of the device 100

201

Sedimentation element of the device 110

202

Sedimentation element of the device 120

203

Sedimentation element of the device 130

204

Sedimentation element of the device 140

209

 outer boundary

210

 Solid layer

215

 Solid particles

220

 binder

225

 Bindmittelgrundmasse

230

 outcoupling

233

 roughened decoupling surface

234

 with microlenses provided decoupling surface

240

 side surface

241

 page element

250

 matrix

300

 potting compound

310

 optical element

400

 mask

410

 recess

420

 opening

430

Surface of the recess 410

500

 arrangement

Claims (15)

Optoelectronic component having a carrier element ( 101 ), one on the carrier element ( 101 ) and electrically contacted semiconductor chip ( 102 ) for emitting electromagnetic radiation, and a the semiconductor chip ( 102 ) downstream sedimentation element ( 200 . 201 . 202 . 203 . 204 ) comprising a binder ( 220 ) and one at least on the semiconductor chip ( 102 ) sedimented solid layer ( 210 ), wherein the sedimentation element ( 200 . 201 . 202 . 203 . 204 ) a decoupling surface ( 230 . 233 . 234 ) for decoupling the from the semiconductor chip ( 102 ) emitted radiation, and wherein the decoupling surface ( 230 . 233 . 234 ) is curved and / or structured. Optoelectronic component according to claim 1, wherein the decoupling surface ( 230 ) is a second order surface. Optoelectronic component according to one of the preceding claims, wherein the decoupling surface ( 230 ) is essentially a hemisphere or a semiellipsoid. Optoelectronic component according to one of the preceding claims, wherein for the maximum height difference max (h _{P1, P2} ) between any two points P1 and P2 on the decoupling surface ( 230 ) the following relation applies max (h _{P1, P2} ) ≥ 0.01 p, (1) where p is the maximum extent of the optoelectronic component ( 100 . 110 . 120 . 150 ). Optoelectronic component according to one of the preceding claims, wherein the decoupling surface ( 233 ) is roughened. Optoelectronic component according to one of claims 1 to 4, wherein the decoupling surface ( 234 ) has a microstructure, in particular microlenses or microprisms. Optoelectronic component according to one of the preceding claims, wherein the semiconductor chip ( 102 ) within one on the support element ( 101 ) projected scope ( 209 ) of the decoupling surface ( 230 . 233 . 234 ) and it applies d ≥ c (2), particularly preferred d = 2c (3), where d is the maximum diameter of the projected perimeter ( 209 ) and c is the length of the diagonal of the semiconductor chip ( 102 ). Optoelectronic component according to one of the preceding claims, wherein the binder ( 220 ) has a refractive index which is lower than the refractive index of the semiconductor chip ( 102 ) and higher than the refractive index of air. Optoelectronic component according to one of the preceding claims, wherein the binder ( 220 ) is a silicone, polysilane, siloxane, polysiloxane, epoxide, polysilazane or a mixture thereof. Optoelectronic component according to one of the preceding claims, further comprising a sedimentation element ( 200 ) subordinate optical element ( 310 ), in particular a lens. Optoelectronic component according to claim 10, wherein the optical element ( 310 ) in a form-fitting manner on the sedimentation element ( 200 ) and the optical element ( 310 ) has a refractive index which is greater than the refractive index of air and less than the refractive index of the sedimentation element ( 200 ). Optoelectronic component according to one of the preceding claims, wherein the solid layer ( 210 ) comprises at least one phosphor, at least one thermally conductive filler, scattering particles or a mixture thereof. Arrangement comprising a carrier element, a semiconductor chip and a mask, comprising a carrier element ( 101 ), one on the carrier element ( 101 ) and electrically contacted semiconductor chip ( 102 ) for the emission of electromagnetic radiation, and a mask ( 400 ) with a semiconductor chip ( 102 ) enclosing recess ( 410 ) for receiving a basic mass ( 250 ), wherein the the semiconductor chip ( 102 ) facing surface ( 430 ) of the recess ( 410 ) is curved and / or structured. Method for producing an optoelectronic component, comprising the steps of providing (S1) one on a carrier element ( 101 ) and electrically contacted semiconductor chips ( 102 ) for the emission of electromagnetic radiation, application (S3, S5) of a matrix comprising a binder base ( 225 ) and solid particles ( 215 ) at least on the semiconductor chip ( 102 ) and simultaneous shaping (S2, S4) of the matrix ( 250 ), Sedimentation (S8) of the solid particles ( 215 ) to a solid layer ( 210 ) at least on the semiconductor chip ( 102 ), and curing (S9) the matrix ( 250 ) to a sedimentation element ( 200 . 201 . 202 . 203 . 204 ), wherein the sedimentation element ( 200 . 201 . 202 . 203 . 204 ) a decoupling surface ( 230 . 233 . 234 ) for decoupling the from the semiconductor chip ( 102 ) and wherein the step of forming (S2, S4) the shaping of the decoupling surface ( 230 . 233 . 234 ), so that the decoupling surface ( 230 . 233 . 234 ) is curved and / or structured. The method of claim 14, wherein the step of forming (S2, S4) comprises providing a mask ( 400 ), in particular the provision of a mask ( 400 ) with a semiconductor chip ( 102 ) enclosing recess ( 410 ), wherein the the semiconductor chip ( 102 ) facing surface ( 430 ) of the recess ( 410 ) is curved and / or structured.

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