Silicon
detectors are commonly used in high-energy physics applications, such as
vertex detectors in colliding particle beams experiments, where ionizing
particle tracks are looked for, or electromagnetic calorimeters, where
one measures the ionizing particle energy loss per unit length of silicon.
In most applications the silicon chip
surface, that is the detector itself , is placed at right angles to the
incoming radiation direction and therefore radiation can be absorbed only
within a few hundred microns of silicon, which is the typical chip thickness.
In medical applications, however, the amount of radiation needed to obtain
a significant image must be minimized and it is essential to extract all
the information contained in the beam used to produce the image. One way
to do this is to maximize detector efficiency.
The
SYRMEP detector achieves a high efficiency, in the
energy interval 15 to 35 keV, thanks to its choice of geometry: the chip
faces the incomimg beam with its side, rather than with its surface, and
impinging photons can be absorbed within the entire chip width, which can
reach a few centimeters. This ensures, in the above energy interval, total
absorption of all incoming photons.