Analysis, Optimization, and Design of 2–2.8 Stacked Multiple-Junction PIN GaInAsSb/GaSb Photodetectors for Future O/E Interconnections

摘要

The 2–2.8 $muhbox{m}$ vertically stacked multiple-junction PIN GaInAsSb/GaSb photodetectors are analyzed, optimized, and designed based on an improved general mode to predict the optimal performance of PIN infrared photodetectors arising from nonequilibrium carrier generation, diffusion, and recombination theory. Optimal thickness of intrinsic absorption region $(W_{rm opt})$, response quantum efficiency ( $RQE$), detectivity $(D^{ ast})$, and $-$3-dB cutoff frequency $(f_{-3, {rm dB}})$ are calculated and optimized for a 2–2.8 $muhbox{m}$ room-temperature high-frequency operation. Ways to achieve optimal performance in practice, material, and device structures are proposed. The optimized vertically stacked multiple-junction PIN GaInAsSb/GaSb photodetector structure shows a $D^{ast}$ of $(hbox{1.6}{-} hbox{1.9}) times hbox{10}^{12} hbox{cm}cdot hbox{Hz}^{1/2}/hbox{W}$, an $RQE$ of 52%–69%, and a $f_{-3, {rm dB}} ≫ hbox{20} hbox{GHz}$ with $W_{rm opt} = hbox{3} muhbox{m}$ and junction number $K = hbox{5}$ , effective illumination area $A_{d} = hbox{1000} muhbox{m}^{2}$ , and reverse bias voltage $V_{rm RB} = hbox{0.5} hbox{V}$ . The proposed general model is validated by simulation and measurement data of fabricated single-junction detectors.