| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor waveguide type photodetector which is small in its coupling loss and high in its sensitivity. SOLUTION: The semiconductor waveguide type photodetector 10 is of a laminated structure which includes a substrate 12 of n-InP, a first light confinement layer 14 of n-AlGaInAs having a thickness of about 3μm and a carrier concentration of about 1×10<18> cm<-3> and an energy band wavelength of about 1.25μm, a non-doped light absorbent layer 16 of AlGaInAs having a thickness of about 0.4μm and an energy band wavelength of about 1.40μm, a second light confinement layer 18 of p-AlGaInAs having a thickness of about 3μm and a carrier concentration of about 1×10<18> cm<-3> and an energy band wavelength of about 1.25μm, a cladding layer 20, and a substrate 22 of p-GaInAs, a sequentially formed on the substrate. With such a structure. the photodetector has a mode field diameter of about 3μm of more which is substantially equal to the mode field diameter of such an optical component as optical fiber coupled with the photodetector and also has a large axis bias tolerance, whereby the element can receive light with a high sensitivity.
|
