Reflectively Coupled Waveguide Photodetector for High Speed Optical Interconnection

Abstract

To fully utilize GaAs high drift mobility, techniques to monolithically integrate In0.53Ga0.47As p-i-n photodetectors with GaAs based optical waveguides using total internal reflection coupling are reviewed. Metal coplanar waveguides, deposited on top of the polyimide layer for the photodetector’s planarization and passivation, were then uniquely connected as a bridge between the photonics and electronics to illustrate the high-speed monitoring function. The photodetectors were efficiently implemented and imposed on the echelle grating circle for wavelength division multiplexing monitoring. In optical filtering performance, the monolithically integrated photodetector channel spacing was 2 nm over the 1,520–1,550 nm wavelength range and the pass band was 1 nm at the −1 dB level. For high-speed applications the full-width half-maximum of the temporal response and 3-dB bandwidth for the reflectively coupled waveguide photodetectors were demonstrated to be 30 ps and 11 GHz, respectively. The bit error rate performance of this integrated photodetector at 10 Gbit/s with 27-1 long pseudo-random bit sequence non-return to zero input data also showed error-free operation.

Recent Progress on Photomultiplication Type Organic Photodetectors

“…Photodetectors, as a converter from optical signal into electrical signal, possess wide applications in various fields: image sensing, optical communication, safety/environmental monitoring, chemical/biological detection, and so on. [1][2][3][4][5][6][7][8][9][10][11] The photodetectors based on a variety of inorganic photoactive materials generally show excellent performances, for example, fast response speed, high gain-bandwidth product, and high stability. [12][13][14][15][16] The commercial photo-detection market is dominated by inorganic photodetectors prepared with silicon (Si), germanium (Ge), or their compounds.…”

Recent advances in solution-processed inorganic nanofilm photodetectors

“…Up to now, there have been many original and review articles devoted to nanostructured materials and set-ups used in photodetectors, these include quantum-dots, [44][45][46][47] quantum-well, [48][49][50][51] 1D nanostructures, [52][53][54][55] Ge-on-Si, 56 ZnO, 57 organic thin-film, 58 Si, 59 lnP, 60 wide-bandgap semiconductors for ultraviolet light detection, 61 gaseous 62 and other kinds. [63][64][65][66][67] However, there have been a very few comprehensive reviews focusing on a variety of solutionprocessed techniques used for inorganic nanofilm photodetector fabrication. This critical review highlights a selection of important topics pertinent to this field over the last 5 years.…”

Metal-assisted chemical etching beyond Si: applications to III–V compounds and wide-bandgap semiconductors

“…GaAs possesses high electron mobility (8500 cm 2 V −1 s −1 ), good thermal characteristics (conductivity 0.55 W cm −1 °C−1 , diffusivity 0.31 cm 2 s −1 , linear expansion 5.73 × 10 −6 °C−1 ) and a zinc blende configuration. 49,50 Optical sensitivity in the near-infrared region, along with the stable crystal structure make GaAs ideal for many optoelectronic [51][52][53] and photovoltaic 54,55 devices, including near-IR photodetectors 31,56 and optical waveguides [57][58][59][60] operating at high enough temperatures to generate thermal carriers. The fabrication of GaAs nanoscale structures is regularly achieved with wet or dry etch techniques; however, there are advantages to MacEtch processing of GaAs for specific applications.…”