Cataloged from PDF version of article.The increasing demand for telecommunication systems resulted in production
of high performance components. Photodetectors are essential components of
optoelectronic integrated circuits and fiber optic communication systems. We
successfully used resonant cavity enhancement technique to improve InGaAs
based p-i-n photodetectors. The detectors had 66% peak quantum efficiency at
1572 nm which showed 3 fold increases with respect to similar photodetector
without resonant cavity. The detectors had 28 GHz 3-dB bandwidth at the same
time. The bandwidth efficiency product for these detectors was 18.5 GHz, which is
one of the best results for InGaAs based vertical photodetector.
The interest in high speed photodetectors is not limited to fiber optic networks.
In the recent years, data communication through the air has become popular due to ease of installation and flexibility of these systems. Although the current systems
still operate at 840 nm or 1550 nm wavelengths, the advantage of mid-infrared
wavelengths will result in the production of high speed lasers and photodetectors.
InSb based p-i-n type photodetectors were fabricated and tested for the operation
in the mid-infrared (3 to 5 µm) wavelength range. The epitaxial layers were grown
on semi-insulating GaAs substrate by molecular beam epitaxy method. The
detectors had low dark noise and high differential resistance around zero bias.
Also the responsivity measurements showed 49% quantum efficiency. The
detectivity was measured as 7.98×109
cm Hz1/2/W for 60 µm diameter detectors.
Finally the high speed measurements showed 8.5 and 6.0 GHz bandwidth for 30
µm and 60 µm diameter detectors, respectively.Kimukin, İbrahimPh.D