# name
Geiger-Mode Avalanche Photodiodes in Standard CMOS Technologies

# metadata.dc.description.abstract[].value
Photodiodes are the simplest but most versatile semiconductor optoelectronic devices. They
can be used for direct detection of light, of soft X and gamma rays, and of particles such as
electrons or neutrons. For many years, the sensors of choice for most research and industrial
applications needing photon counting or timing have been vacuum-based devices such as
Photo-Multiplier Tubes, PMT, and Micro-Channel Plates, MCP (Renker, 2004). Although
these photodetectors provide good sensitivity, noise and timing characteristics, they still
suffer from limitations owing to their large power consumption, high operation voltages
and sensitivity to magnetic fields, as well as they are still bulky, fragile and expensive. New
approaches to high-sensitivity imagers tend to use CCD cameras coupled with either MCP
Image Intensifiers, I-CCDs, or Electron Multipliers, EM-CCDs (Dussault & Hoess, 2004), but
they still have limited performances in extreme time-resolved measurements.
A fully solid-state solution can improve design flexibility, cost, miniaturization, integration
density, reliability and signal processing capabilities in photodetectors. In particular, Single-
Photon Avalanche Diodes, SPADs, fabricated by conventional planar technology on silicon
can be used as particle (Stapels et al., 2007) and photon (Ghioni et al., 2007) detectors with
high intrinsic gain and speed. These SPAD are silicon Avalanche PhotoDiodes biased above
breakdown. This operation regime, known as Geiger mode, gives excellent single-photon
sensitivity thanks to the avalanche caused by impact ionization of the photogenerated
carriers (Cova et al., 1996). The number of carriers generated as a result of the absorption of
a single photon determines the optical gain of the device, which in the case of SPADs may
be virtually infinite.
The basic concepts concerning the behaviour of G-APDs and the physical processes taking
place during their operation will be reviewed next, as well as the main performance
parameters and noise sources.

# metadata.dc.rights[].value
cc by (c) Vilà i Arbonès, Anna Maria et al., 2012

# metadata.dc.source[].value
Llibres / Capítols de llibre (Enginyeria Electrònica i Biomèdica)

# metadata.dc.title[].value
Geiger-Mode Avalanche Photodiodes in Standard CMOS Technologies