Les photodiodes Si sont les diodes pin à polarisation inverse. Elles détectent la lumière dans une gamme de 250 nanomètres à 1,1 µm. Le rayonnement incident est transformé en photo-courant mesurable.
Silicon photodiodes and arrays with scintillators for X-ray applications in medical technology.
With the increasing importance of passenger safety in air and train transportation, X-ray detectors are in more and more demand for inspection of cargo. Among other things, silicon line detectors are used to record the contents of passing, illuminated luggage as quickly and reliably as possible.
The X-ray beam emitted is highly energetic. Therefore, standard Si photodiodes cannot be used for detection. The beam would pass through the diodes without being able to be absorbed.
In order to successfully detect the beam, manufacturers rely on scintillators. Scintillators are crystals made of materials such as, for example, Tl-doped CsI. They are applied to photodiode surfaces and convert incident X-ray beams into visible light (565 nm) that can be detected by a Si photodiode.
A typical example of this technology is the PDB-C216, a Si-PIN array with 16 elements which is available with a CsI (Tl) scintillator. Thanks to their borderless design, these arrays can be infinitely strung together and the detector surface is thus as long as necessary. In addition to such standard products offered by Advanced Photonix, they also have a variety of custom-made components available, naturally including X-ray detectors for applications in medical technology.