Hybrid Photon Couting Detector Theory


An incoming photon is directly converted into an electrical charge using a detection material such as silicon, gallium arsenide or cadmium telluride. This charge is proportional to the energy of the incoming photon: this is quantum detection.
The resulting charge is collected on each pixels by the way of a Read Out Integrated Component that will count each individual charge that reach a threshold .

Technology benefits  :

Accurate counting : only detected photons or charged particle (electrons or protons) are counted, the electronic noise is totaly eliminated.
Energy Discrimination : the threshold allows for the descimination of Photons based on their energy.
Counting dynamic : The counting dynamic range  is almost limiteless
High Acquisition Rate : This technology is designed to handle
high acquisition rates, reaching frequencies of about kHz.


Xpad 3.2 Read Out Integrated Chip

XPad 3.2 main features
Active detection area 1,5x1cm²
Pixels number 9600
Dynamic Range 12bits+Overflow
Maximum Linear Counting rate 7.105ph/sec/pix
Point-spread function 1 pixel
Optimum Working Energy 7-60KeV
Threshold range 5-35KeV
Frame Rate 800 Hz
The Xpad component project has starded early at the end of th 90s by the Center for Particle Physics of Marseille. This French CNRS Entity of National Institute for Nuclear and Particle Physics In2P3) is one of the hybrid pixel technology precursor involved in detectectors designed for the CERN facilities. The French Synchrotron Soleil, the Neel institut with D2AM ( BM02 beam line at ESRF) and the CRM² (unniversité de Lorraine) where implied as the first users of this technology. Today Cegitek is the unique company offering detectors based on the Xpad 3.2 component for several customers arround the world…

A Look at a real case detection...

Cegitek has rapidly developed specialized expertise in the design and manufacture of small and large surface hybrid pixel photon counting detectors.

crm2_5_v3 (1)

Silicon Pouder difrraction
540 RebirX detector
(Credits CRM² Unniversité de Lorraine 2018)


Electrons direct detection 15x10mm²
detector under Ultra High Vacuum
Atomic Terrases Formation on Silicon
LEEM equipment (Credits CINAM 2017)

Cegitek Xpad detection modules for RebirX detectors

Cegitek RebirX Detection module with no dead zone