Vertical-cavity surface-emission type laser diode and fabrication process thereof

A method of fabricating a vertical-cavity, surface-emission-type laser diode, said vertical-cavity, surface-emission-type laser diode comprising:

• a semiconductor substrate;
• and
• an optical cavity structure provided on or above said semiconductor substrate, said optical-cavity structure comprising an active region containing at least one active layer that produces a laser beam, and upper and lower reflectors sandwiching said active region to form said optical cavity, said lower reflector including a semiconductor distributed Bragg reflector having a refractive index that changes periodically, said lower reflector reflecting an optical beam incident thereto by diffraction, said semiconductor distributed Bragg reflector comprising a low-refractive-index layer of AlxGa1-xAs (0<x≦1) and a high-refractive-index layer of AlyGa1-yAs (0≦y<x≦1), a layer of GaxIn1-xPyAs1-y (0<x≦1, 0<y≦1) being provided between said active layer and said lower reflector, said method comprising the steps of:
• forming said lower reflector by depositing one or more layers containing Al;
• forming said layer of GaxIn1-xPyAs1-y (0<x≦1, 0<y≦1), and
• forming said active layer containing nitrogen on said lower reflector,
• wherein there is provided a step of removing a residual material containing Al such as an Al source or Al reactant or Al compound or Al, from a site in which the residual material makes a contact with a nitrogen source material or an impurity contained in the nitrogen source material, after growth of said layer containing Al but before the end of growth of said layer of GaxIn1-xPyAs1-y (0<x≦1, 0<y≦1).

A vertical-cavity, surface-emission-type laser diode comprising:

• a semiconductor substrate;
• and
• an optical cavity structure provided on or above said semiconductor substrate,
• said optical-cavity structure comprising an active region containing at least one active layer that produces a laser beam, and upper and lower reflectors sandwiching said active region to form said optical cavity,
• said lower reflector including a semiconductor distributed Bragg reflector having a refractive index that changes periodically, said lower reflector reflecting an optical beam incident thereto by diffraction,
• said semiconductor distributed Bragg reflector comprising a low-refractive-index layer of AlxGa1-xAs (0<x≦1) and a high-refractive-index layer of AlyGa1-yAs (0≦y<x≦1),
• wherein a GaxIn1-xPyAs1-y (0<x≦1, 0<y≦1) layer is provided between said active layer and said lower reflector including an interface between said lower reflector and said active region.