CMOS-Compatible PureGaB Ge-on-Si APD pixel arrays

A Sammak, Mahdi Aminian, LK Nanver, E Charbon

Research output: Contribution to journalArticleScientificpeer-review

7 Citations (Scopus)
39 Downloads (Pure)


Pure gallium and pure boron (PureGaB) Ge-on-Si photodiodes were fabricated in a CMOS compatible process and operated in linear and avalanche mode. Three different pixel geometries with very different area-to-perimeter ratios were investigated in linear arrays of 300 pixels with each a size of 26 × 26 μm2. The processing of anode contacts at the anode perimeters leaving oxide covered PureGaB-only light-entrance windows, created perimeter defects that increased the vertical Ge volume but did not deteriorate the diode ideality. The dark current at 1 V reverse bias was below 35 μA/cm2 at room temperature and below the measurement limit of 2.5 × 10-2 μA/cm2 at 77 K. Spread in dark current levels and optical gain, that reached the range of 106 at 77 K, was lowest for the devices with largest perimeter. All device types were reliably operational in a wide temperature range from 77 K to room temperature. The spectral sensitivity of the detectors extended from visible to the telecom band with responsivities of 0.15 and 0.135 A/W at 850 and 940 nm, respectively.
Original languageEnglish
Pages (from-to)92-99
Number of pages8
JournalIEEE Transactions on Electron Devices
Issue number1
Publication statusPublished - 2016


  • Photodiodes
  • Silicon
  • Temperature measurement
  • Optical device fabrication
  • Optical imaging
  • CMOS integrated circuits
  • Optical sensors

Fingerprint Dive into the research topics of 'CMOS-Compatible PureGaB Ge-on-Si APD pixel arrays'. Together they form a unique fingerprint.

Cite this