Method of fabricating nitride-based compound layer, GaN substrate and vertical structure nitride-based semiconductor light emitting device
View Patent ↗In a method for fabricating a nitride-based compound layer, first, a GaN substrate is prepared. A mask layer with a predetermined pattern is formed on the GaN substrate to expose a partial area of the GaN substrate. Then a buffer layer is formed on the partially exposed GaN substrate. The buffer layer is made of a material having a 10% or less lattice mismatch with GaN. Thereafter, the nitride-based compound is grown laterally from a top surface of the buffer layer toward a top surface of the mask layer and the nitride-based compound layer is vertically grown to a predetermined thickness. Also, the mask layer and the buffer layer are removed via wet-etching to separate the nitride-based compound layer from the GaN substrate.
1. A method for fabricating a nitride-based compound layer, comprising steps of:
preparing a GaN substrate;
forming a mask layer with a predetermined pattern on the GaN substrate to expose a partial area of the GaN substrate;
forming a buffer layer on the partially exposed GaN substrate, the buffer layer made of a material having a 10% or less lattice mismatch with GaN;
laterally growing a nitride-based compound from a top surface of the buffer layer toward a top surface of the mask layer and vertically growing the nitride-based compound layer to a predetermined thickness; and
removing the mask layer and the buffer layer via wet-etching to separate the nitride-based compound layer from the GaN substrate,
wherein the buffer layer is in direct contact with the GaN substrate and made of a material removable together with the mask layer in the wet-etching process.
2. The method according to claim 1 , wherein the buffer layer has a 5% or less lattice mismatch with GaN.
3. The method according to claim 1 , wherein the buffer layer comprises one selected from a group consisting of ZnO, Ga 2 O 3 and ZrB 2 .
4. The method according to claim 1 , wherein the mask layer comprises a silicon oxide film or a silicon nitride film.
5. The method according to claim 1 , wherein a wet-etching solution used in the wet-etching comprises HCl or HF.
6. A method for fabricating a GaN substrate comprising steps of:
preparing a seed GaN substrate;
forming a mask layer with a predetermined pattern on the seed GaN substrate to expose a partial area of the GaN substrate;
forming a buffer layer on the partially exposed seed GaN substrate, the buffer layer made of a material having a 10% or less lattice mismatch with GaN;
laterally growing the GaN from a top surface of the buffer layer toward a top surface of the mask layer and vertically growing the GaN to form the GaN substrate with a predetermined thickness; and
removing the mask layer and the buffer layer via wet-etching to separate the GaN substrate from the seed GaN substrates,
wherein the buffer layer is in direct contact with the GaN substrate and made of a material removable together with the mask layer in the wet-etching process.
7. The method according to claim 6 , wherein the buffer layer has a 5% or less lattice mismatch with GaN.
8. The method according to claim 6 , wherein the buffer layer comprises ZnO, Ga 2 O 3 and ZrB 2 .
9. The method according to claim 6 , wherein the mask layer comprises a silicon oxide film or a silicon nitride film.
10. The method according to claim 6 , wherein a wet-etching solution used in the wet-etching comprises HCl or HF.
11. The method according to 6 , wherein the GaN substrate forming step comprises growing the GaN by HVPE.
12. A method for fabricating a nitride-based compound layer, comprising steps of:
preparing a GaN substrate;
forming a mask layer with a predetermined pattern on the GaN substrate to expose a partial area of the GaN substrate;
forming a buffer layer on the partially exposed GaN substrate, the buffer layer made of Ga 2 O 3 or ZrB 2 ;
laterally growing nitride-based compound from a top surface of the buffer layer toward a top surface of the mask layer and vertically growing the nitride-based compound layer to a predetermined thickness; and
removing the mask layer and the buffer layer via wet-etching to separate the nitride-based compound layer from the GaN substrate.
13. The method according to claim 12 , wherein the mask layer comprises a silicon oxide film or a silicon nitride film.
14. The method according to claim 12 , wherein a wet-etching solution used in the wet-etching comprises HCl or HF.