Surface emitting semiconductor laser, surface emitting semiconductor laser device, light transmission apparatus, and information processing apparatus
View Patent ↗A surface emitting semiconductor laser includes a substrate, a first semiconductor multi-layer reflector formed on the substrate and including a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a relatively low refractive index which are laminated, a semi-insulating i type AlGaAs layer formed on the first semiconductor multi-layer reflector, an n type semiconductor layer formed on the AlGaAs layer, an active region formed on the semiconductor layer, a p type second semiconductor multi-layer reflector formed on the active region and including a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a relatively low refractive index which are laminated, an n side first electrode electrically connected to the semiconductor layer, and a p side second electrode electrically connected to the second semiconductor multi-layer reflector.
1. A surface emitting semiconductor laser comprising:
a substrate;
a first semiconductor multi-layer reflector formed on the substrate and including a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a relatively low refractive index which are laminated;
a semi-insulating i type AlGaAs layer formed on the first semiconductor multi-layer reflector and having an optical film thickness larger than an oscillation wavelength;
an n type semiconductor layer formed on the AlGaAs layer, not having a deep level due to an impurity, or the deep level being higher than a Γ level, and capable of having a lattice matching with the substrate;
an active region formed on the semiconductor layer;
a p type second semiconductor multi-layer reflector formed on the active region and including a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a relatively low refractive index which are laminated;
an n side first electrode electrically connected to the semiconductor layer; and
a p side second electrode electrically connected to the second semiconductor multi-layer reflector;
wherein
a length of a resonator defined by the first semiconductor multi-layer reflector the AlGaAs layer, the semiconductor layer, the active region, and the second semiconductor multi-layer reflector is greater than the oscillation wavelength,
at least two resonant wavelengths are included in a reflection band of the resonator, and
a selected resonant wavelength is oscillated.
2. The surface emitting semiconductor laser according to claim 1 , wherein the semiconductor layer is made of an n type GaInP.
3. The surface emitting semiconductor laser according to claim 1 , wherein the first semiconductor multi-layer reflector is of a semi-insulating i type.
4. The surface emitting semiconductor laser according to claim 2 , wherein the first semiconductor multi-layer reflector is of a semi-insulating i type.
5. The surface emitting semiconductor laser according to claim 1 , wherein
a columnar structure from the second semiconductor multi-layer reflector to the semiconductor layer is formed,
the second electrode electrically connected to the second semiconductor multi-layer reflector is formed on a top portion of the columnar structure, and
the first electrode electrically connected to the second semiconductor multi-layer reflector is formed on the semiconductor layer which is exposed at a bottom portion of the columnar structure.
6. The surface emitting semiconductor laser according to claim 1 , wherein a current confining layer is formed inside the second semiconductor multi-layer reflector.
7. The surface emitting semiconductor laser according to claim 1 , wherein
the first semiconductor multi-layer reflector includes a pair of an AlGaAs layer having a relatively high Al composition and an AlGaAs layer having a relatively low Al composition, and
the second semiconductor multi-layer reflector includes a pair of an AlGaAs layer having a relatively high Al composition and an AlGaAs layer having a relatively low Al composition.
8. The surface emitting semiconductor laser according to claim 1 , wherein the semiconductor layer is made of n type AlGaInP.
9. The surface emitting semiconductor laser according to claim 1 , wherein the semiconductor layer is made of n type AlGaAsP.
10. A surface emitting semiconductor laser comprising:
a p type semiconductor substrate;
a p type first semiconductor multi-layer reflector formed on the semiconductor substrate and including a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a relatively low refractive index which are laminated;
an active region formed on the first semiconductor multi-layer reflector;
an n type semiconductor layer formed on the active region, not having a deep level due to an impurity, or the deep level being higher than a Γ level, and capable of having a lattice matching with the substrate;
a semi-insulating i type AlGaAs layer formed on the semiconductor layer;
a second semiconductor multi-layer reflector formed on the AlGaAs layer and including a pair of a high refractive index layer having a relatively high refractive index and a low refractive index layer having a relatively low refractive index which are laminated;
an n side first electrode electrically connected to the semiconductor layer; and
a p side second electrode electrically connected to the first semiconductor multi-layer reflector.
11. The surface emitting semiconductor laser according to claim 10 , wherein the semiconductor layer is made of n type GaInP.
12. The surface emitting semiconductor laser according to claim 10 , wherein
a length of a resonator defined by the first semiconductor multi-layer reflector, the active region, the semiconductor layer, the AlGaAs layer, and the second semiconductor multi-layer reflector is greater than the oscillation wavelength,
at least two resonant wavelengths are included in a reflection band of the resonator, and
a selected resonant wavelength is oscillated.
13. The surface emitting semiconductor laser according to claim 10 , wherein
a columnar structure from the second semiconductor multi-layer reflector to the semiconductor layer is formed,
the first electrode electrically connected to the second semiconductor multi-layer reflector is formed on the semiconductor layer which is exposed at a bottom portion of the columnar structure, and
the second electrode electrically connected to the first semiconductor multi-layer reflector is formed on a rear surface of the semiconductor substrate.
14. The surface emitting semiconductor laser according to claim 10 , wherein the semiconductor layer is made of n type AlGaInP.
15. The surface emitting semiconductor laser according to claim 10 , wherein the semiconductor layer is made of n type AlGaAsP.
16. A surface emitting semiconductor laser device comprising:
the surface emitting semiconductor laser according to claim 1 ; and
an optical member to which light from the surface emitting semiconductor laser is incident.
17. A light transmission apparatus comprising:
the surface emitting semiconductor laser device according to claim 16 ; and
a transmission unit that transmits laser light emitted from the surface emitting semiconductor laser device via an optical medium.
18. An information processing apparatus comprising:
the surface emitting semiconductor laser according to claim 1 ;
a condenser that collects laser light emitted from the surface emitting semiconductor laser at a recording medium; and
a mechanism that scans the laser light collected by the condenser on the recording medium.