Claims
- 1. In a green light emitting device comprising an n-type GaP substrate, an n-type GaP layer formed on the substrate and a p-type GaP layer formed on the n-type GaP layer, the improvement wherein said n-type GaP layer includes a first layer formed on the GaP substrate and a second layer directly formed on the first layer, said second layer being closer to the p-type GaP layer, the net donor concentration in said first layer being higher than the net donor concentration in said second layer, the donor concentration in said first layer being abruptly decreased to that of said second layer, and said second layer containing nitrogen at a higher concentration than in said first layer.
- 2. A green light emitting device according to claim 1, wherein the net donor concentration in said first layer is at least twice the net donor concentration in said second layer.
- 3. A green light emitting device according to claim 1, wherein the net donor concentration of said first layer is lower than that of the n-type GaP substrate.
- 4. A green light emitting device according to claim 2, wherein the nitrogen concentration in the second layer is at least 1.times.10.sup.18 /cm.sup.3.
- 5. A green light emitting device according to claim 2 or 4, wherein the thickness of the first layer is at least 10 .mu.m and that of the second layer is 10 to 35 .mu.m.
- 6. A green light emitting device according to claim 2 or 4, wherein the ratio of the net donor concentration of the first layer to that of the second layer falls within 3 to 20.
- 7. A green light emitting device according to claim 2 or 4, wherein a major donor impurity of the first layer is silicon and a major donor impurity of the second layer is one of sulfur and tellurium.
- 8. A green light emitting device according to claim 1, 2, 3, or 4, wherein the first and second layers, and the p-type GaP layer are liquid-phase epitaxial layers, respectively.
- 9. A green light emitting device according to claim 8, wherein the first and second layers are liquid-phase epitaxial layers formed by dissolving a portion of the substrate and recrystallizing the dissolved portion of the substrate.
- 10. A green light emitting device according to claim 5, wherein the ratio of the net donor concentration of the first layer to that of the second layer falls within 3 to 20.
- 11. A green light emitting device according to claim 5, wherein a major donor impurity of the first layer is silicon and a major donor impurity of the second layer is one of sulfur and tellurium.
- 12. A green light emitting device according to claim 6, wherein a major donor impurity of the first layer is silicon and a major donor impurity of the second layer is one of sulfur and tellurium.
- 13. A green light emitting device according to claim 5, wherein the first and second layers, and the p-type GaP layer are liquid-phase epitaxial layers, respectively.
- 14. A green light emitting device according to claim 13, wherein the first and second layers are liquid-phase epitaxial layers formed by dissolving a portion of the substrate and recrystallizing the dissolved portion of the substrate.
- 15. In a green light emitting device comprising an n-type GaP substrate, an n-type GaP layer formed on the substrate and a p-type GaP layer formed on the n-type GaP layer, the improvement wherein said n-type GaP layer includes a first layer formed on the GaP substrate and a second layer directly formed on the first layer, said second layer being closer to the p-type GaP layer, the net donor concentration in said first layer being between 1.times.10.sup.17 /cm.sup.3 and 5.times.10.sup.16 /cm.sup.3, the net donor concentration in said second layer being between 1.times.10.sup.16 /cm.sup.3 and 5.times.10.sup.16 /cm.sup.3, the donor concentration in said first layer being abruptly decreased to that of said second layer, and said second layer containing nitrogen at a higher concentration than in said first layer.
Priority Claims (2)
Number |
Date |
Country |
Kind |
52-120037 |
Oct 1977 |
JPX |
|
52-120039 |
Oct 1977 |
JPX |
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CROSS REFERENCE TO THE RELATED APPLICATION
This application is a continuation-in-part of application Ser. No. 169,612, filed on July 17, 1980 which is a continuation application Ser. No. 950,049, filed on Oct. 10, 1978.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4101920 |
Nagasawa |
Jul 1978 |
|
Continuations (1)
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Number |
Date |
Country |
Parent |
950049 |
Oct 1978 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
169612 |
Jul 1980 |
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