Gallium nitride-based compound semiconductor light-emitting device and production method thereof
The invention provides a gallium nitride based compound semiconductor light emitting device with excellent light extracting efficiency and its production method. A light emitting device, obtained from a gallium nitride based compound semiconductor, includes a substrate; a n-type semiconductor layer 13 , a light emitting layer 14 , and a p-type semiconductor layer 15 , sequentially stacked on a substrate 11 ; a light-permeable positive electrode 16 stacked on the p-type semiconductor layer 15 ; a positive electrode bonding pad 17 provided on the light-permeable positive electrode 16 ; and a negative electrode bonding pad provided 18 on the n-type semiconductor layer 13 , wherein a disordered uneven surface formed at least on a part of the surface 15 a of the p-type semiconductor layer 15.
1. A gallium nitride based compound semiconductor light emitting device production method, for forming an uneven surface at least on a part of the p-type semiconductor layer of the gallium nitride based compound semiconductor device,
comprising:
process 1, stacking an n-type semiconductor layer, a light emitting layer, and a p-type semiconductor layer sequentially to form gallium nitride based compound semiconductor on a substrate;
process 2, forming a mask made of metallic particles on the p-type semiconductor layer; and
process 3, dry-etching p-type semiconductor layer using the mask made of metallic particles as an etching mask to form the uneven surface.
2. A production method of gallium nitride based compound semiconductor light emitting device according to claim 1 , wherein the process 2 comprises a process forming a metallic film on the p-type semiconductor layer and a heat treatment process after the formation of the metallic film.
3. A production method of gallium nitride based compound semiconductor light emitting device according to claim 1 , wherein the metallic particles that form the mask are obtained from Ni or Ni alloy.
4. A production method of gallium nitride based compound semiconductor light emitting device according to claim 1 , wherein the metallic particles that form the mask are obtained from a low melting point metal or a low melting point alloy with a melting point in a range of 100° C. to 450° C.
5. A production method of gallium nitride based compound semiconductor light emitting device according to claim 1 , wherein the metallic particles that form the mask are obtained from a low melting point metal selected from a group consisting of Ni, Au, Sn, Ge, Pb, Sb, Bi, Cd, and In, or obtained from a low melting point alloy comprising at least one of the low melting point metal selected from the same group.