Laser diode having an active layer containing N and operable in a 0.6 μm wavelength band

A vertical-cavity laser diode, comprising:

• a substrate having a first conductivity type;
• a first optical reflector provided on said substrate;
• a first cladding layer having said first conductivity type on said first optical reflector in an epitaxial relationship with said substrate;
• a first optical waveguide layer formed epitaxially on said first cladding layer;
• an active layer of a group III-V compound semiconductor material formed epitaxially on said first cladding layer;
• a second optical waveguide layer formed epitaxially on said active layer,
• a second cladding layer having a second, opposite conductivity type on said active layer in an epitaxial relationship with said second optical waveguide layer;
• a second optical reflector provided on said second cladding layer;
• a first ohmic electrode provided in ohmic contact with said substrate;
• a second ohmic electrode provided in ohmic contact with said second cladding layer;
• and
• between said first optical waveguide layer and said active layer, an intermediate layer of a group III-V compound semiconductor material substantially free from Al and N in intimate contact with said active layer,
• said active layer having a composition of GaInNP containing therein N as a group V element.

An optical disk drive, comprising:

• a spindle motor adapted to be mounted with an optical disk, said spindle motor rotating said optical disk mounted thereon;
• and
• an optical pickup focusing an optical beam on a recording surface of said optical disk mounted on said spindle motor,
• said optical pickup including a vertical-cavity layer diode comprising:
• a substrate having a first conductivity type;
• a first optical reflector provided on said substrate;
• a first cladding layer having said first conductivity type on said first optical reflector in an epitaxial relationship with said substrate;
• a first optical waveguide layer formed epitaxially on said first cladding layer;
• an active layer of a group III-V compound semiconductor material formed epitaxially on said first optical waveguide layer;
• a second optical waveguide layer formed epitaxially on said active layer;
• a second cladding layer having a second, opposite conductivity type on said second optical waveguide layer in an epitaxial relationship with said active layer;
• a second optical reflector provided on said second cladding layer;
• a first ohmic electrode provided in ohmic contact with said substrate;
• a second ohmic electrode provided in ohmic contact with said second cladding layer;
• and
• between said first optical waveguide layer and said active layer, an intermediate layer of a group III-V compound semiconductor material substantially free from Al and N in intimate contact with said active layer,
• said active layer having a composition of GaInNP containing therein N as a group V element.

An optical transmission system including an optical transmitter and a plastic optical fiber coupled optically with said optical transmitter, said optical transmitter including a vertical cavity laser diode comprising:

• a substrate having a first conductivity type;
• a first optical reflector provided on said substrate;
• a first cladding layer having said first conductivity type on said first optical reflector in an epitaxial relationship with said substrate;
• a first optical waveguide layer formed on said first cladding layer epitaxially;
• an active layer of a group III-V compound semiconductor material formed epitaxially on said, first optical waveguide layer;
• a second optical waveguide layer formed on said active layer epitaxially;
• a second cladding layer having a second, opposite conductivity type on said second optical waveguide layer in an epitaxial relationship with said active layer;
• a second optical reflector provided on said second cladding layer;
• a first ohmic electrode provided in ohmic contact with said substrate;
• a second ohmic electrode provided in ohmic contact with said second cladding layer;
• and
• between said first optical waveguide layer and said active layer, an intermediate layer of a group III-V compound semiconductor material substantially free from Al and N in intimate contact with said active layer,
• said active layer having a composition of GaInNP containing therein N as a group V element.

An optical semiconductor device, comprising:

• a substrate;
• a first layer of a III-V compound semiconductor material formed over said substrate epitaxially, said first layer being substantially free from N;
• an active layer of a III-V compound semiconductor material formed over said first layer epitaxially in intimate contact therewith, said active layer containing N as a group V element;
• a second layer of a III-V compound semiconductor material formed over said active layer epitaxially in intimate contact therewith, said second layer being substantially free from N,
• an interface between said first layer and said active layer contains C with a concentration level exceeding a concentration level of C in any of said first and active layers.