Laser diode epitaxial wafer and method for producing same
View Patent ↗A laser diode epitaxial wafer includes an n-type GaAs substrate, an n-type cladding layer formed on the n-type GaAs substrate, an active layer formed on the n-type cladding layer, and a p-type cladding layer formed on the active layer. The n-type cladding layer, the active layer, and the p-type cladding layer include an AlGaInP-based material. The p-type cladding layer has carbon as a p-type impurity. The p-type cladding layer has a carrier concentration between 8.0×10 17 cm −3 and 1.5×10 18 cm −3 .
1. A laser diode epitaxial wafer, comprising:
an n-type GaAs substrate;
an n-type cladding layer formed on the n-type GaAs substrate;
an active layer formed on the n-type cladding layer; and
a p-type cladding layer formed on the active layer,
wherein the n-type cladding layer, the active layer, and the p-type cladding layer each comprise an AlGaInP-based material and have a double-hetero structure,
wherein the p-type cladding layer comprises a p-type impurity consisting of carbon,
wherein the p-type cladding layer has a carrier concentration between 8.0×10 17 cm −3 and 1.5×10 18 cm −3 ,
wherein the p-type cladding layer comprises a carrier concentration distribution in a depth direction thereof of within ±5%,
wherein the p-type cladding layer has a thickness of 1.5 μm or more, and
wherein the active layer comprises an undoped active layer and a carrier concentration of not more than 7.0×10 16 cm −3 .
2. The laser diode epitaxial wafer according to claim 1 , wherein the n-type cladding layer comprises silicon as an n-type impurity.
3. The laser diode epitaxial wafer according to claim 1 , wherein the p-type cladding layer has a carrier concentration between 9.0×10 17 cm −3 and 1.2×10 18 cm −3 .
4. The laser diode epitaxial wafer according to claim 1 , further comprising:
a p-type GaAs cap layer doped with Zn and formed on the p-type cladding layer, the p-type GaAs cap layer comprising a carrier concentration of at least 1.0×10 19 cm −3 .
5. The laser diode epitaxial wafer according to claim 1 , wherein the p-type cladding layer is doped with the carbon by using CBr 4 .
6. The laser diode epitaxial wafer according to claim 1 , wherein the p-type cladding layer comprises a single layer.
7. The laser diode epitaxial wafer according to claim 1 , wherein the p-type cladding layer has a uniform carrier concentration distribution.
8. The laser diode epitaxial wafer according to claim 1 , wherein the p-type cladding layer functions as the p-type cladding layer independent of another p-type cladding layer in the laser diode epitaxial wafer.
9. The laser diode epitaxial wafer according to claim 1 , wherein the n-type cladding layer is doped with silicon.
10. The laser diode epitaxial wafer according to claim 1 , wherein the active layer comprises an undoped layer.
11. The laser diode epitaxial wafer according to claim 1 , further comprising:
an undoped guide layer comprising AlGaInP between the active layer and the p-type cladding layer.