WO2017178467A1

WO2017178467A1 - Light-emitting component

Info

Publication number: WO2017178467A1
Application number: PCT/EP2017/058640
Authority: WO
Inventors: David Racz; Ulrich Streppel
Original assignee: Osram Opto Semiconductors Gmbh
Priority date: 2016-04-13
Filing date: 2017-04-11
Publication date: 2017-10-19
Also published as: DE102016106851A1

Abstract

The invention relates to a light-emitting component (1) having a substrate (2), wherein a light-emitting semiconductor chip (3) is arranged on a first side of the substrate, wherein the substrate is transparent, wherein a reflecting layer (6) is provided on a second side, which is arranged to be located opposite the first side, wherein the reflecting layer (6) leads the light emitted by the semiconductor chip (3) at least partly back into the substrate (2), wherein a conversion layer (9) is provided at least on a part of a side surface of the substrate which is arranged between the first and the second side.

Description

LIGHT-EMITTING COMPONENT

DESCRIPTION

The invention relates to a light-emitting element ge ^¬ Mäss claim. 1

This patent application claims the priority of German patent application DE 10 2016 106 851.9, which is dependent Offenbarungsge ^¬ hereby incorporated by reference.

In the prior art it is known to provide light-emitting construction ^¬ elements comprising a support and a light-emitting semiconductor chip. The light emitting devices are used, for example, to enable display backlighting. This requires a broad-beam secondary optics.

The object of the invention is to provide an improved light emitting device.

The object of the invention is achieved by the device according to Pa ^¬ tentanspruch 1. Further advantageous embodiments of the component are specified in the dependent claims.

A light-emitting component with a carrier is proposed, wherein a light-emitting semiconductor chip is arranged on the carrier. Opposite the semi-conductor chip ^¬, the support has a reflective layer that is re-directed light emitted by the semiconductor chip light incident via the carrier to the reflecting layer, at least partially ^stabilized back into the carrier. Furthermore, a conversion layer is provided at least at a partial area of the side surface of the carrier. The conversion layer is formed to the laterally emitted light from the semiconductor chip at least partially ben in the wavelength to various ^¬. Thus, a desired color mixture, in particular a white light can be generated. With the help of the proposed ^¬ nen component a low height is achieved, wherein In addition, a good lateral radiation of the light is possible.

In one embodiment, the reflective layer is formed as a mirror layer. Thereby, a high proportion of the light incident on the layer, reflected back into the Trä ^¬ ger. Thus, a high efficiency for a ^¬ since Liche emission of light is achieved. Under a seitli ^¬ chen radiation, the radiation is understood to mean a side surface of the component. In addition, the mirror layer has the advantage that the layer thickness is very thin. Thus, a particularly low overall height of the component is made ^¬ light. For example, the overall height of the component may be in the range of less than 10 mm, in particular in the range of 2 mm and smaller.

In addition, due to the proposed arrangement, no secondary optics is required to direct the light generated by the semiconductor chip in a desired lateral direction. Since the secondary optics can be dispensed with, no effort is required to place the lenses.

In addition, due to the proposed arrangement, good color uniformity of the emitted over the side surface of the component light with respect is he ^¬ reaches a beam angle.

In a further embodiment, the reflective layer is formed as a light-scattering layer. Although the light-scattering layer builds slightly higher than the mirror ^¬ layer, but has the advantage that a diffuse light scattering and reflection of the light back into the carrier takes place. Depending on the selected embodiment, the mirror layer and / or the light-scattering layer can extend into the lateral region of the conversion layer and can also be formed on the conversion layer.

The semiconductor chip is formed, for example, in the form of epitaxially grown semiconductor layers. Especially For example, the semiconductor layers may be grown on the carrier.

Depending on the chosen embodiment, the conversion layer surrounds the carrier on the entire side surface. In addition, the conversion layer can at least partially or completely limit not only the side surface of the carrier, but also the side surface of the semiconductor chip. In this way, a homogeneous light is radiated from the component over the entire side surface. In the arrangement of Konversi ^¬ onsschicht also on the side of the semiconductor chip, a further improvement in the homogeneity of the emitted light is achieved, since also the laterally emitted from the semiconductor chip light is emitted through the conversion layer.

In one embodiment, the carrier is formed with a rectangular contour. In contrast, the conversion layer in the proposed embodiment has an at least partially rounded outer contour. Thus, a more uniform light emission can be achieved.

In a further embodiment, the conversion layer surrounds the carrier completely and has a rounded rectangular outer contour or a polynomial rounded outer contour or an elliptical outer contour. The shape of the outer contour may be formed in a manner to achieve a desired color mixing of the emitted light in seitli ^¬ cher direction. In addition, the shape of the outer contour can be used to produce regardless of the direction of the light emission of an approximately equal wavelength of the light, ie light of the same color.

In one embodiment, the component has a rectangular area, that is to say a rectangular outer contour. The conversion layer completely surrounds the carrier in the lateral direction and has four rounded bulges. From ^¬ pending chosen from the embodiment, it may be advantageous to arrange the protrusions in each case centrally in relation to a Be ^¬ tenfläche of the rectangular carrier. In a In another embodiment, it may be advantageous to arrange the rounded bulges respectively centrally with respect to a corner of the carrier. In another embodiment, a side surface of the component is assigned a light guide, wherein light is coupled into the light guide via the Be ^¬ tenfläche of the device. In this way, an improved guidance of the light in a desired direction can be achieved with the aid of the light guide.

In a further embodiment, the light guide is designed as a housing, wherein the component is at least partially disposed in a recess of the housing. Thus, a compact structure of the device can be achieved, at the same time a light-conducting function of the radiated light from the component is achieved by means of the housing. In addition, the housing can protect in the form of the light guide the Bauele ^¬ ment to damage. Furthermore, with the help of the housing, a desired light pipe, in particular a light pipe in the lateral radiation direction, can be achieved.

In a further embodiment, the light guide has scattering structures on a first side. Thus, an improved light guide can be achieved in a desired Auskoppelrichtung.

The scattering structures can be arranged in a uniform grid with a predetermined distance from each other. In addition, the scattering structures may have the same size areas. Thus, a homogeneous radiation of the light in the area of the scattering structures can be achieved. Another IMPROVE ^¬ tion of the scattering structures can be achieved by the diffusing structures comprise a light diffusing material. The light-scattering material may be formed, for example, in the form of a color. For example, a white color can be used that reflects 70% of the light and 30% lets through the light. The scattering structure may comprise, for example, titanium oxide.

In a further embodiment, the recess counter to the component lying on a bottom surface, said bottom surface having a light-scattering ^¬ end or a light reflective layer at least in a partial area. On the ^¬ se, a further improvement of the side exhaust radiation of light can be achieved. This embodiment is particularly advantageous when the device has no reflective layer, but a scattering layer or no scattering or reflective layer opposite to the semi ^¬ conductor chip. Depending on the chosen embodiment, the housing may have a light reflecting layer at least on a second side, which is opposite to a first side. The light-reflecting layer is in particular ^¬ sondere disposed opposite to the side having the scattering structures.

The above-described characteristics, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following description of the exemplary embodiments, which will be explained in more detail in conjunction with the drawings. Show it

FIG. 1 shows a schematic cross section through an embodiment of the component,

FIG. 2 shows a schematic view of an embodiment of the component with an angular support and with a conversion layer with a round outer contour,

FIG. 3 shows a schematic plan view of a component with an angular support with a conversion layer with an angular outer contour, Figure 4 is a schematic plan view of a further exporting ^¬ approximate shape of a component with a conversion layer having a rounded rectangular outer contour,

FIG. 5 shows a schematic plan view of a further embodiment of the component with a conversion layer with a rounded free form as the outer contour,

Figure 6 is a plan view of a further embodiment ei ^¬ nes component with a conversion layer having a abge ^¬ rounded asymmetrical outer contour,

Figure 7 is a schematic plan view of a further exporting ^¬ approximate shape of a component with a conversion layer having an elliptical outer contour,

8 shows a schematic cross section through a further embodiment of the component, which is arranged in a housing ^¬ , and

9 shows a schematic cross section through FIG. 8 perpendicular to the cross section of FIG. 9.

FIG. 1 shows, in a schematic cross section, a component 1 which has a carrier 2. On a lower side of the carrier 2, a semiconductor chip 3 is arranged. The half ^¬ semiconductor chip 3 has a layered structure including semiconductor layers comprising an active region for generating electromagnetic radiation ^¬ shear. In addition, electrical connections 4, 5 for operating the semiconductor chip 3 are provided on the underside of the semiconductor chip. The electrical connections 4, 5 are, for example, designed in the form of soldering pads and connected in an electrically conductive manner to a p-side or to an n-side of the layer structure. The semiconductor chip 3 may be formed in the form of epitaxially grown on the support semiconductor layers with an active zone for generating electromagnetic radiation. In addition, the semiconductor chip may be formed as a sapphire flip-chip. Of the Semiconductor chip 3 may also have other forms of training.

Opposite to the semiconductor chip 3, the carrier 2 has a reflective layer 6 on an upper side. The re ^¬ inflectional layer 6 is formed to light incident from the semiconductor chip 3 by the support 2 to the reflective layer 6, at least partially to steer back to the carrier. 3 Under light becomes electromagnetic

Understood radiation, wherein the wavelength can also be outside the visible range. The reflective layer 6 may be formed, for example, as a mirror layer or as a scattering layer. The mirror layer can be formed, for example, of silver or aluminum or in the form of dielectric layers. Furthermore, in the embodiment, the reflective layer 6 may be formed as a scattering layer as a white light-scattering layer. The diffusing layer 6 may, for example, a Trägermateri ^¬ al eg silicone and scattering particles have, for example of titanium oxide and / or barium sulfate.

The carrier 2 is formed of a material that substantially transmits light, which is generated by the semiconductor chip 3, and absorbs it only to a small extent. For example, the carrier 2 can be made of sapphire. However, other materials such. As glass can be used. The Trä ^¬ ger 2 is covered at side surfaces 7,8 with a conversion material 9. The conversion material 9 can luminescent Ma ^¬ materials such. B. phosphor, the light emitted from the semiconductor chip 3 light at least partially in the

Wavelength shifts. In particular, the Konversionsma ^¬ TERIAL 9 can be used to produce a light having a desired wavelength and a desired wavelength range. For example, with the aid of a semiconductor chip that generates blue light and a corresponding Konversi ^¬ onsmaterial 9 total white light emitted sideways. The reflective layer 6 is disposed in the illustrated example exporting ^¬ approximately on an upper side of Konversionsmateri ^¬ as. 9 In addition, depending on the selected embodiment, the reflective layer 6 may be arranged only on the carrier 2. The conversion material 9 can cover all Be ^¬ tenflächen the wearer second The conversion material 9 may additionally, as shown also cover the entire Seitenflä ^¬ surfaces of the semiconductor chip. 3 The formation of the reflective layer 6 as a mirror layer can be done by depositing metal or dielectric materials, for example by means of a sputtering method. The conversion material 9 can be formed laterally on the carrier 2 and the semiconductor chip 3, for example with the aid of a mold process. In addition, for the formation of the conversion material 9 and mold method can be used. The formation of the reflective layer 6 as the diffusion layer can be carried out, for example, by means of a molding process.

In the preparation of the component 1, a plurality of components with the carrier and the semiconductor chip may be disposed, which are subsequently converted with conversion material 9 ^¬ ben. Thereafter, the reflective layer is placed ^¬ on the plurality of carriers, and the conversion material. 6 Subsequently, the components are separated for example by means of sawing process or by means of Laserschnei ^¬ de-method. The reflective layer 6 may have a thickness in the range of 50 ym to 500 ym, depending on the chosen embodiment. The carrier 2 with the semiconductor chip 3 may have a thickness in the range of 100 ym to 1000 ym, depending on the selected embodiment.

Figure 2 shows a schematic cross section through an embodiment of the device 1, which is constructed substantially in accordance with FIG. The carrier 2 is rectangular in shape and the conversion material 9 has circular Au ßenkontur on. Depending on the particular embodiment, the semiconductor chip 3 may cover the entire underside of the carrier 2 or only part of the underside of the carrier 2. The reflective layer 6 preferably covers an entire top side of the carrier 2 and an entire top side of the conversion material 9 and thus has the outer contour of a circular disk in the exemplary embodiment shown.

Figure 3 shows a further embodiment of a device 1 in cross-section, substantially in accordance with FIG. Ausgebil ^¬ det 1. The carrier 2 is rectangular in shape, wherein the conversion material 9 has a rectangular outer contour. Thus, in this embodiment, the reflective layer 6, which is not shown, has a rectangular, in particular square shape. Figures 2 and 3 each show a component which is constructed substantially in accordance with Figure 1, but with the outer contours of the conversion material 9 differ. Figure 4 shows a schematic cross section through a further embodiment of the device 1, which is constructed substantially in accordance with Figure 1, wherein the carrier 2 has a quadra ^¬ table shape. The conversion material 9 has a rounded outer contour 10. The outer contour 10 has a first distance A in the region of the side surfaces 7, 8, 11, 12. In the region of corners 13 of the carrier 2, the outer ^¬ contour 10 at a distance B on. Temptations have shown that a more homogeneous color of light over the entire Be ^¬ tenflächen of the device 1 can be achieved when the second distance B is in the range of 0.2 to 0.8 times the first distance A.

Figure 5 shows a further embodiment of a device 1 with a schematic cross-section, wherein the device 1 is constructed substantially in accordance with Figure 1, except that the conversion material 9 has an outer contour 10 having a SYMMETRI ^¬ rule polynomial free-form. In this embodiment, the outer contour has 10 rounded bulges 14, 15, 16, 17, the center region in each case in a middle a side surface 7, 8, 11, 12 of the carrier 2 are arranged. The bulges have a convex outer contour in cross section. The bulges 14, 15, 16 each have a first distance A, which is the same for all bulges. In addition, the outer contour 10 in the region of the corners 13 of the carrier 2 to a second distance B, which is in the range between 0.2 and 0.8 times the first distance A.

FIG. 6 shows a diagrammatic cross section through a further embodiment of the component 1, the component being constructed substantially in accordance with FIG. 1, wherein, however, the conversion material 9 has an outer contour 10 which has a non-symmetrical polynomial freeform. The second spacing B in the areas of the corners 13 of the carrier 2 are formed to be larger than the first distances A to Be ^¬ area of the side surfaces 7, 8, 11, 12 of the carrier. 2

FIG. 7 shows a further embodiment of the component 1 in a schematic cross section. The component 1 is constructed essentially according to FIG. 1, but the conversion material 9 has an outer contour 10 which has an elliptical shape.

Figure 8 shows a further embodiment of the device 1 in cross-section, the device 1 is constructed substantially in accordance with Figure 1 and is arranged in a recess 18 of a Gehäu ^¬ ses 19th In this case, the recess 18 has a Bo ^¬ denfläche 20, which faces the reflective layer 6 of the component 1. Between the reflective layer 6 of the device 1 and the bottom surface 20, a free space 25 is formed.

On the bottom surface 20, a second stray or spat ^¬ terrain layer may be provided 21st The housing 19 receives the device 1 at least partially. The housing 19 is we ^¬ nigstens partially of a light-conducting material gebil ^¬ det, which leads the light of the semiconductor chip 3 and is transparent to the light. Thus, the housing 19 is a light guide. In addition, depending on the selected output Guidance form a reflector layer 22 may be formed on a bottom of the housing 19. The reflector layer 22 can cover the entire housing surface. In addition, the re ^¬ flektorschicht 22 also covers the region of the recess 18th The reflector layer 22 serves to reflect light which falls from the housing 19 or from the component 1 onto the reflector layer 22, back to ^¬ . The reflector layer may be formed, for example, as a mirror layer or as a scattering layer. Depending on the selected embodiment, the housing 19 may have scattering structures 24 on an upper side 23. The scattering structures 24 serve to better decouple light from the housing 19. The scattering structures 24 may have a round or angular surface in the plane of the upper side 23 of the housing 19. The scattering structures 24 may be in the form of a coating or in the form of a mechanical structure of the upper side 23 of the housing 19. The Streustruktu ^¬ ren 24 may be arranged a fixed grid at fixed intervals. The housing 19 may be made of a light-conducting material such. As PMMA or polycarbonate Herge ^¬ provides. The housing 19 may have a thickness in a Y direction perpendicular to the plane of the carrier 2 in the range of 1500 to 3000 microns. FIG. 9 shows a schematic cross section through FIG. 8 in the plane of the carrier 8, wherein a part of the scattering structures 24 is shown in dashed lines. In this view, the regular arrangement of the scattering structures 24 can be detected in a grid with equal intervals. In addition, the scattering structures 24 are identical in the example chosen.

In the illustrated embodiment, the scattering structures 24 are formed in the form of circular surfaces. However, any other type of surface can be used. In addition, Kings ^¬ NEN the scattering structures 24 in an irregular grid, that is, be located at different distances. The scattering structures 24 may be made of silicon, for example. kon with titanium oxide on the top 23 of the housing 19 is ^¬ forms.

The scattering structures can be formed from highly reflective, diffuse scattering material. Thus, an off ^¬ coupling is avoided over the top of the housing 19 and the light emitted substantially over side surfaces of the housing 19. As a result, a desired lateral radiation of the light from the housing 19 is achieved. Use of the scattering structure, a desired radiation over the upper side 23 or on other side faces 26,27,28,29 of the Gehäu ^¬ ses 19 can be achieved.

Depending on the chosen embodiment, the housing 19 may also have other shapes. In particular, other forms of light guides to be coupled to a side surface of the construction element 1 at least ^¬.

With the aid of the proposed component 1 or with the aid of the component 1 with the housing 19, in particular a ver ^¬ improved display backlighting can be achieved, which provides a high homogeneity of light. In addition, with the aid of the proposed components, backlighting of LCD displays, in particular in LCD televisions, can be provided, the components being distributed behind the display surface. Specifically, each semiconductor device may be formed separately ansteu ^¬ Erbar and dimmable. Thus, a homogeneous ^¬ re image illumination with improved contrast and black levels can be achieved.

Although the invention in detail by the preferred embodiment has been illustrated and described in detail, the invention is not limited ^¬ by the disclosed examples and other variations can be derived therefrom by the skilled artisan without departing from the scope of the invention. LIST OF REFERENCE NUMBERS

1 component

2 carriers

3 semiconductor chip

4 First electrical connection

5 Second electrical connection

6 reflective layer

7 First side surface

8 Second side surface

9 conversion material

10 outer contour

11 Third side surface

12 Fourth side surface

13 corner

14 First bulge

15 Second bulge

16 Third bulge

17 Fourth bulge

18 recess

19 housing

20 floor space

21 Second reflective layer

22 reflector layer

23 top

24 scattering structure

25 free space

26 more first side surface

27 more second side surface

28 more third side surface

29 more fourth side surface

Claims

PATENTA'S TEST

1. A light-emitting component (1) having a carrier (2), wherein a light-emitting semiconductor chip (3) is arranged on a first side of the carrier (2), wherein the carrier (2) is translucent, wherein on a second side, which is arranged opposite the first side, a reflective layer (6) is provided, wherein the reflective layer (6) the light emitted from the semiconductor chip at least partially in the

Carrier (2) deflects, wherein at least on a part of a side surface (7, 8, 11, 12) of the carrier (2), which is arranged between the first and the second side, a conversion layer (9) is provided.

2. The component according to claim 1, wherein the reflective

Layer (6) is formed as a mirror layer.

3. The component according to claim 1, wherein the reflective

Layer (6) is designed as a light-scattering layer.

4. The component according to one of the preceding claims, wherein the conversion layer (9) surrounds the carrier (2) on all Be ^¬ tenflächen (7, 8, 11, 12).

5. The component according to one of the preceding claims, wherein the conversion layer (9) surrounds the semiconductor chip (3) on al ^¬ len side surfaces. 6. The component according to claim 4 or 5, wherein the carrier (2) has a rectangular outer contour, and wherein the conversion layer (9) has an at least partially abgerun ^¬ finished outer contour (10).

Component according to one of claims 4 to 6, wherein the conversion layer (9) has a rounded rectangular outer contour (10) or a rounded polinomiale Au ^¬ ßenkontur (10) or an elliptical outer contour.

8. The component of claim 7, wherein the carrier (2) has a rectangular outer contour, wherein the conversion ^¬ layer (9) of the support (2) surrounds, and wherein the convergence immersion layer (9) has four rounded lobes (14, 15,

16, 17), wherein the bulges (14, 15, 16, 17) are each arranged centrally with respect to a length of a side surface ^¬ (7, 8, 11, 12) of the carrier. 9. The component according to claim 7, wherein the carrier (2) has a

has rectangular outer contour, wherein the conversion ^¬ layer (9) surrounds the carrier (2), and wherein the Konver ^¬ sion layer (9) has four rounded protrusions (14, 15, 16, 17), wherein the bulges (14, 15, 16, 17) in each case centrally with respect to a corner (13) of the Trä ^¬ gers (2) are arranged.

10. The component according to one of the preceding claims, wherein a side surface (7, 8, 11, 12) of the carrier (2) is associated with a light guide (19), wherein over the side surface ^¬ (7, 8, 11, 12) of the Carrier (2) light is coupled into the light ^¬ conductor.

11. The component according to claim 10, wherein the light guide is formed as a housing (19), wherein the component (1) in a recess (18) of the housing (19) is arranged.

12. The component according to one of claims 10 or 11, wherein the light guide (19) on a top (23) scattering structures (24).

13. The component according to claim 12, wherein the scattering structures

(24) are arranged in a uniform grid with a predetermined distance from each other, wherein the Streustru tures (24) have the same areas, and / or wherein the

Scattering structures have a light-scattering material.

14. The component according to one of claims 11 to 13, wherein the recess (18) has a bottom surface (20), wherein the Floor surface (20) above the component (1) is arranged, and wherein the bottom surface (20) at least in a partial area a light-scattering and / or lichtreflektie- rende layer (21)

15. The component according to any one of claims 10 to 14, wherein the housing (19) on a second side which is disposed opposite to lie quietly ^¬ a first side, has a lichtre ^¬ inflectional layer (22).