Resonant cavity enhanced GaInNAs-based IR photodetector with gain

In this study, quasi-cavity and resonant cavity p-i-n junction Ga_{1-x}In_xN_yAs_{1-y}/GaN_zAs quantum well (QW) photodetectors which have the potential to be used of at 1.3 um window of fibre optical communication have been investigated. Design, fabrication, electrical and optical characterization of photodetectors have been carried out depending on numbers of QWs and Distributed Bragg Reflectors (DBRs), materials of active region and barrier layer.\par In the design stage of the photodetectors, Band Anti-Crossing model, Transfer Matrix Method and Vegard's law utilized. The bandgap energy of the absorption region, lattice match between the layers and the quality of the resonance cavity were taken into account as the design parameters. The photodetectors were grown on 2 inch wafers by using Molecular Beam Epitaxy (MBE) at Optoelectronics Research Centre/Tampere University of Technology (Finland). The photodetectors were fabricated as mesa structure with a diameter of 20-200 um by using facilities of Advanced Lithography Laboratories/Istanbul University Science Faculty Physics Department. Electrical and optical characterization of the photodetectors were carried out at Nano-Optoelectronic Research Laboratories/Istanbul University Science Faculty. Temperature dependency of absorption wavelengths, thermal expansion coefficients and cavity wavelength of the photodetectors were obtained by temperature-dependent photoluminescence and reflectance measurements between 30 and 300K. Dark current, responsivity and quantum efficiencies of the photodetectors were obtained by current-voltage and photocurrent measurements. Bandwidth, detectivity and noise of photodetectors were obtained from the analysis of transient photoconductivity which were carried out at University of Essex (United Kingdom) All obtained results are presented by comparing with the literature. All the best photodetector characteristic has been obtained for resonant cavity 9 QWs Ga_{0.65}In_{0.35}N_{0.02}As_{0.98}/GaAs photodetector with AlAs/AlGaAs 21 periods top and 25 periods bottom DBRs. With this photodetector structure, quantum efficiency (QE) of 43% has been achieved at a very low bias -1 V. To the best of our knowledge which is the highest QE in the dilute nitrogen resonant cavity photodetectors in the literature. This photodetector has been patented as a National Patent by Turkish Patent and Trademark Office with patent number of TR 2015 05193 B.