Crosstalk Analysis for Mesa-based In-device Passivated InGaAs Photodetectors


Conference on Optical Components and Materials XIX at SPIE OPTO Conference, ELECTR NETWORK, 22 January - 28 February 2022, vol.11997 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 11997
  • Doi Number: 10.1117/12.2609730
  • Keywords: Short Wavelength Infrared, InGaAs/InP, mesa type, in-device passivation, dark current reduction, inter-pixel crosstalk suppression, DESIGN, LAYER
  • Middle East Technical University Affiliated: Yes


Electrical crosstalk of in-device passivated mesa-based InGaAs photodetectors has been analyzed by a three-pixel mini array illuminated from the backside. In-device passivation of mesa-based lattice-matched InGaAs photodetectors significantly suppresses the surface-related component of dark current-however, inter-pixel crosstalk increases due to the depletion condition of the in-device passivation layer between the pixels. The inter-pixel crosstalk originates mainly from the high electric field in the in-device passivation layer. Here, in mesa-based in-device passivated InGaAs photodetectors, inter-pixel crosstalk has been significantly improved by adjusting the electric field distribution between the pixels with the inclusion of a thin n-InP crosstalk-block layer without affecting the primary purpose of the detector structure, which is strong resistivity to surface-related dark current increase.