Method of making a long wavelength indium gallium arsenide nitride (InGaAsN) active region
View Patent ↗The active region of a long-wavelength light emitting device is made by providing an organometallic vapor phase epitaxy (OMVPE) reactor, placing a substrate wafer capable of supporting growth of indium gallium arsenide nitride in the reactor, supplying a Group III–V precursor mixture comprising an arsenic precursor, a nitrogen precursor, a gallium precursor, an indium precursor and a carrier gas to the reactor and pressurizing the reactor to a sub-atmospheric elevated growth pressure no higher than that at which a layer of indium gallium arsenide layer having a nitrogen fraction commensurate with light emission at a wavelength longer than 1.2 μm is deposited over the substrate wafer.
1. A method of making the active region of a long-wavelength light emitting device, the method comprising:
providing an organometallic vapor phase epitaxy (OMVPE) reactor;
placing in the reactor a substrate wafer capable of supporting growth of indium gallium arsenide nitride;
supplying to the reactor a Group III–V precursor mixture comprising an arsenic precursor, a nitrogen precursor, a gallium precursor, an indium precursor and a carrier gas;
adjusting the flow rate of the arsenic precursor to grow an InGaAsN material having an internal quantum efficiency of radiative recombination approaching 100%; and
pressurizing the reactor to a sub-atmospheric elevated growth pressure no higher than that at which a layer of indium gallium arsenide nitride having a nitrogen fraction commensurate with light emission at a wavelength longer than 1.2 μm is deposited over the substrate wafer.
2. The method of claim 1 , in which the pressurizing comprises pressurizing the reactor to a sub-atmospheric pressure of at least 100 millibars.
3. The method of claim 2 , in which the pressurizing comprises pressurizing the reactor to a sub-atmospheric pressure greater than 200 millibars.
4. The method of claim 1 , wherein the adjusting comprises adjusting the flow rate of the arsenic precursor to provide a partial pressure thereof of approximately 1 millibar.
5. The method of claim 1 , wherein the arsenic precursor comprises one of arsine, tertiarybutylarsine, trimethylarsenic, phenylarsine, trisdimethylaminoarsine, triethylarsenic, monoethylarsine and diethylarsenic hydride.
6. The method of claim 5 , wherein the nitrogen precursor comprises one of hydrazine, dimethylhydrazine, phenylhydrazine, ammonia, tertiarybutylamine nitrogen trifluoride and excited nitrogen.
7. The method of claim 1 , wherein the nitrogen precursor comprises one of hydrazine, dimethylhydrazine, phenylhydrazine, ammonia, tertiarybutylamine nitrogen trifluoride and excited nitrogen.
8. The method of claim 1 , wherein the arsenic precursor consists essentially of tertiarybutylarsine.
9. The method of claim 8 , wherein the nitrogen precursor consists essentially of dimethylhydrazine.
10. The method of claim 1 , wherein the nitrogen precursor consists essentially of nitrogen trifluoride.
11. A method of making the active region of a long-wavelength light emitting device, the method comprising:
providing an organometallic vapor phase epitaxy (OMVPE) reactor;
placing in the reactor a substrate wafer capable of supporting growth of indium gallium arsenide nitride;
supplying to the reactor a Group III–V precursor mixture comprising an arsenic precursor, a gallium precursor, an indium precursor and a carrier gas;
growing a sublayer of InGaAs;
discontinuing supply of the Group III–V precursor mixture; and
supplying to the reactor a Group V precursor mixture comprising an arsenic precursor and a nitrogen precursor in which the concentration of the nitrogen precursor exceeds that of the arsenic precursor.
12. The method of claim 11 , wherein the nitrogen precursor comprises at least one of hydrazine, dimethylhydrazine, phenylhydrazine, ammonia, tertiarybutylamine nitrogen trifluoride and excited nitrogen.
13. The method of claim 11 , wherein the arsenic precursor comprises at least one of arsine, tertiarybutylarsine, trimethylarsenic, phenylarsine, trisdimethylaminoarsine, triethylarsenic, monoethylarsine and diethylarsenic hydride.
14. The method of claim 11 , additionally comprising, between the growing and the discontinuing:
discontinuing supply of the indium precursor; and
growing a monolayer of GaAs on the sublayer.
15. A method of making the active region for a long-wavelength light emitting device, the method comprising:
providing an organometallic vapor phase epitaxy (OMVPE) reactor;
placing a substrate wafer in the reactor;
supplying to the reactor a Group III–V precursor mixture comprising an arsenic precursor, a nitrogen precursor, a gallium precursor, an indium precursor and a carrier gas in which the concentration of the nitrogen precursor exceeds the concentration of the arsenic precursor; and
pressurizing the reactor to a growth pressure of at least 100 millibars but less than 1000 millibars to grow a layer of indium gallium arsenide nitride.
16. The method of claim 15 , wherein the substrate wafer consists essentially of gallium arsenide (GaAs).
17. The method of claim 15 , wherein the pressurizing comprises pressurizing the reactor to a growth pressure no greater than that which ensures that a concentration of nitrogen commensurate with light emission at a wavelength longer than 1.2 μm is extracted from the nitrogen precursor and is deposited on the substrate wafer.
18. The method of claim 15 , wherein the nitrogen precursor comprises one of hydrazine, dimethylhydrazine, phenylhydrazine, ammonia, tertiarybutylamine nitrogen trifluoride and excited nitrogen.
19. The method of claim 15 , wherein the arsenic precursor comprises one of arsine, tertiarybutylarsine, trimethylarsenic, phenylarsine, trisdimethylaminoarsine, triethylarsenic, monoethylarsine and diethylarsenic hydride.
20. The method of claim 15 , wherein the pressurizing comprises pressurizing the reactor to a growth pressure of greater than 200 millibars but less than 1000 millibars to grow the layer of indium gallium arsenide nitride.
21. A method of making the active region of a long-wavelength light emitting device, the method comprising:
providing an organometallic vapor phase epitaxy (OMVPE) reactor;
placing a substrate wafer in the reactor;
supplying to the reactor a Group III precursor mixture and a Group V precursor mixture, the Group III precursor mixture comprising a gallium precursor and an indium precursor, the Group V precursor mixture comprising an arsenic precursor and a nitrogen precursor; and
growing a layer of indium gallium arsenide nitride comprising a nitrogen fraction commensurate with light emission at a wavelength longer than 1.2 μm over the substrate wafer, the growing comprising minimizing the concentration of the arsenic precursor consistent with growth of material of high electro-optical quality by discontinuing the flow of the Group III precursor mixture and reducing the flow of the arsenic precursor during supply of the nitrogen precursor to the reactor, and by maximizing the concentration of the nitrogen precursor in the Group V precursor mixture.
22. The method of claim 21 , wherein the minimizing the concentration of the arsenic precursor comprises pressurizing the reactor to a sub-atmospheric growth pressure of at least 100 millibar.