Radiation-emitting chip and radiation-emitting component
View Patent ↗A radiation-emitting chip ( 2 ) with a radiation-transmissive window ( 5 ), which has a refractive index n F and has a main area ( 19 ), with a multilayer structure ( 9 ), which contains a radiation-active layer ( 10 ) and adjoins the main area ( 19 ) of the window ( 5 ), and with a radiation-transmissive medium surrounding the window ( 5 ) and having the refractive index n 0 , the window ( 5 ) having at least two boundary areas ( 6, 7 ), which form an angle β, for which the relationship 90°−α t <β<2α t where α t =arc sin( n 0 /n F ) is satisfied. A radiation-emitting component contains a chip ( 2 ) of this type.
1. A radiation-emitting chip ( 2 ) with a radiation-transmissive window ( 5 ), which has a refractive index n F and a main area ( 19 ), and with a multilayer structure ( 9 ), which contains a radiation-generating active layer ( 10 ) and is arranged at the main area ( 19 ) of the window ( 5 ),
the window ( 5 ) being surrounded by a radiation-transmissive medium having a refractive index n 0 , which is less than the refractive index n F of the window,
characterized in that
the window ( 5 ) is bounded toward the radiation-transmissive medium at least by two areas ( 6 , 7 ), which form an angle β, for which the relationship
90°−α t <β<2α t
is satisfied, where α t is given by
α t =arc sin ( n 0 /n F ).
2. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the two areas ( 6 , 7 ) are side areas of the window ( 5 ).
3. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the window ( 5 ), parallel to the main area ( 19 ), has a triangular cross section with the internal angles β, γ and δ.
4. The radiation-emitting chip ( 2 ) as claimed in claim 3 ,
characterized in that
the relationship
90°−α t <γ<2α t
is satisfied for γ.
5. The radiation-emitting chip ( 2 ) as claimed in claim 4 ,
characterized in that
the relationship
90°−α t <δ<2α t
is satisfied for δ.
6. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the window ( 5 ) has at least one side area ( 13 a ), which, relative to the multilayer structure ( 9 ), runs obliquely or in curved fashion or is stepped in such a way that the window ( 5 ) tapers as seen from the multilayer structure ( 9 ).
7. The radiation-emitting chip ( 2 ) as claimed in claim 6 ,
characterized in that
the window has a side area ( 13 b ) arranged perpendicular to the multilayer structure ( 9 ), which side area, as seen from the multilayer structure, is arranged downstream of the side area ( 13 a ) which runs obliquely or in curved fashion or is formed in stepped fashion, and in particular adjoins said side area.
8. The radiation-emitting chip ( 2 ) as claimed in claim 6 ,
characterized in that
at least the side area ( 13 a ) which runs obliquely or concavely or is stepped is roughened.
9. The radiation-emitting chip ( 2 ) as claimed in claim 6 ,
characterized in that
the window ( 5 ) has the form of a prism in the region of the side area ( 13 b ) running perpendicularly to the multilayer structure ( 9 ).
10. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the multilayer structure ( 9 ) is fabricated epitaxially and the window ( 5 ) is produced from a substrate used for the epitaxy.
11. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the refractive index n F of the window is greater than the refractive index of the multilayer structure ( 9 ), in particular of the active layer ( 10 ).
12. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
that side of the window ( 5 ) which is opposite to the multilayer structure ( 9 ) is a mounting side of the chip ( 2 ).
13. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the multilayer structure is formed from semiconductor layers.
14. The radiation-emitting chip ( 2 ) as claimed in claim 13 ,
characterized in that
the multilayer structure ( 9 ) contains at least one of the compounds GaN, AlGaN, InGaN or AlInGaN.
15. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the window ( 5 ) contains SiC.
16. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the window ( 5 ) contains sapphire.
17. The radiation-emitting chip ( 2 ) as claimed in claim 1 ,
characterized in that
the medium surrounding the window ( 5 ) is a reaction resin.
18. The radiation-emitting chip ( 2 ) as claimed in claim 17 ,
characterized in that
the reaction resin contains an epoxy resin, a silicone resin, an acrylic resin or a mixture of these resins.
19. A radiation-emitting component,
characterized in that
it contains a radiation-emitting chip ( 2 ) as claimed in claim 1 .
20. The radiation-emitting component as claimed in claim 19 ,
characterized in that
it has a housing basic body ( 24 ), onto which the radiation-emitting chip ( 2 ) is mounted.
21. The radiation-emitting component as claimed in claim 20 ,
characterized in that
a recess ( 23 ) is formed in the housing basic bodywork ( 24 ), the radiation-emitting chip ( 2 ) is arranged in said recess.
22. The radiation-emitting component as claimed in claim 19 ,
characterized in that
the recess is filled with the medium surrounding the chip ( 2 ) or the window ( 5 ).
23. The radiation-emitting component as claimed in claim 22 ,
characterized in that
the recess is filled with a reaction resin.
24. The radiation-emitting component as claimed in claim 23 ,
characterized in that
the reaction resin contains an epoxy resin, a silicone resin, an acrylic resin or a mixture of these resins.