High-performance ITO-AlAs/GaAs based resonant cavity enhanced Schottky photodiodes

The fabrication of ITO (indium tin oxide)-AlAs-based resonant cavity enhanced Schottky photodiodes was examined. The device structure was designed to achieve a low-loss cavity around a 840 nm optical communication window. The layers were grown by molecular beam epitaxy on a GaAs substrate. Photoresponse measurements were carried out in 750-900 nm wavelength range using a tungsten-halogen projection lamp as the light source and single pass monochromator. Although the discrepancy between the experiment and theory was quite large, a nearly parallel enhancement of the initial efficiency values was observed as a function of the top distributed Bragg reflector pair

High-speed widely-tunable >90% quantum-efficiency resonant cavity enhanced p-i-n photodiodes

Widely-tunable high-speed resonant cavity enhanced p-i-n photodiodes were designed, fabricated and tested for operation around 820 nm. The structure was grown by solid-source MBE on GaAs substrates and features high-reflectivity Bragg mirrors made of quarter-wave Al0.20Ga0.80As/AlAs stacks. Photoresponse and photospectral measurements were carried out. The tuning of the resonance wavelength within the Bragg mirror's upper and lower edges was observed. Quantum efficiency greater than 90% was demonstrated

High-speed high-efficiency resonant cavity enhanced photodiodes

In this paper, we review our research efforts on RCE high-speed high-efficiency p-i-n and Schottky photodiodes. Using a microwave compatible planar fabrication process, we have designed and fabricated GaAs based RCE photodiodes. For RCE Schottky photodiodes, we have achieved a peak quantum efficiency of 50% along with a 3-dB bandwidth of 100 GHz. The tunability of the detectors via a recess etch is also demonstrated. For p-i-n type photodiodes, we have fabricated and tested widely tunable devices with near 100% quantum efficiencies, along with a 3-dB bandwidth of 50 GHz. Both of these results correspond to the fastest RCE photodetectors published in scientific literature

High-speed 1.3 μm GaAs internal photoemission resonant cavity enhanced photodetector

Photoresponse measurements were carried out in the 1100-1500 nm range by using a single-pass monochromator and a tungsten-halogen projection lamp as the light source. Further, high-speed measurements were made with an optical parametric oscillator (OPO). In general, the results correspond to the first high-speed internal photoemission photodetectors