Method for fabricating a radiation-emitting semiconductor chip based on III-V nitride semiconductor, and radiation-emitting semiconductor chip
View Patent ↗A method for fabricating a radiation-emitting semiconductor chip having a thin-film element based on III-V nitride semiconductor material includes the steps of depositing a layer sequence of a thin-film element on an epitaxy substrate. The thin-film element is joined to a carrier, and the epitaxy substrate is removed from the thin-film element. The epitaxy substrate has a substrate body made from PolySiC or PolyGaN or from SiC, GaN or sapphire, which is joined to a grown-on layer by a bonding layer, and on which the layer sequence of the thin-film element is deposited by epitaxy.
1. A radiation-emmiting semiconductor chip, comprising:
a thin-film element having a plurality of layers formed from a III-V nitride semiconductor material, said thin-film element having an n-conducting side and a p-conducting side;
an electrically conductive carrier, said p-conducting side of said thin-film element applied to said electrically coductive carrier; and
a contact surface applied on said n-conducting side of said thin-film element, said thin-film element containing a buffer layer being an epitaxy layer adjoining said contact surface, said epitaxy layer formed of an AlGaN-based material and having a first side adjoining said contact surface with a lower Al content than a second side of said epitaxy layer remote from said contact surface, said buffer layer having a plurality of electrically conductive regions made from a different III-V nitride semiconductor material than a remainder of said buffer layer.
2. The semiconductor chip according to claim 1 , wherein said plurality of electrically conductive regions is formed from a material selected from the group consisting of an InGaN-based material, InN and GaN.
3. The semiconductor chip according to claim 2 , wherein said electrically conductive regions are formed from a material selected from the group consisting of In 1-x Ga x N,where 0≦x<1, and In 1-x-y Al x Ga y N, where 0≦x<1, 0≦y<1 and x+y<1, with an Al content which is so low that said electrically conductive regions are formed.
4. The semiconductor chip according to claim 1 , wherein said buffer layer is formed from a plurality of individual layers based on AlGaN.
5. The semiconductor chip according to claim 4 , wherein: said thin-film element has a layer sequence adjoining said buffer layer; said plurality of individual layers of said buffer layer includes a first individual layer adjoining said layer sequence, said first individual layer having a higher Al content than a second individual layer following said first individual layer.
6. The semiconductor chip according to claim 1 , wherein said carrier transmit or partially transmit radiation produced.
7. The semiconductor chip according to claim 1 , wherein said carrier has a layer which reflects radiation produced or at least in part is provided with a surface that reflects the radiation produced.