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• Does your sensor convert the stimulus directly into electric output?

The best energy resolution in modern radiation detectors can be achieved in semiconductorsemiconductor materials, where a comparatively large number of carriers for a given incidentincident radiation event occurs. In these materials, the basic information carriers are electron–hole pairs created along the path taken by the charged particle through the detector. The charged particle can be either primary radiation or a secondary particle. TheThe electron–hole pairs in some respects are analogous to the ion pairs produced in thethe gas-filled detectors. When an external electric field is applied to the semiconductivesemiconductive material, the created carriers form a measurable electric current. The detectors operatingoperating on this principle are called a solid-state or semiconductor diode detectors . The(Figure 1). The operating principle of these radiation detectors is the same as that of the semiconductorsemiconductor light detectors. It is based on the transition of electrons from one energy levellevel to another when they gain or lose energy.[1].

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• What steps are required to transform the signal into electric output?

To fabricate a solid-state detector, at least two contacts must be formed across
a across a semiconductor material. For detection, the contacts are connected to the voltage
sourcevoltage source, which enables carrier movement. The use of a homogeneous Ge or Si, however,
would  would be totally impractical. The reason for that is in an excessively high leakage current caused by the material’s relatively low resistivity (50 kcm kΩ for silicon).When
When applied to the terminals of such a detector, the external voltage may cause a current
current which is three to five orders of magnitude greater than a minute radiation-induced
induced electric current. Thus, the detectors are fabricated with the blocking junctions, which
which are reverse biased to dramatically reduce leakage current. In effect, the detector is
is a semiconductor diode which readily conducts (has low resistivity) when its anode
anode (p side of a junction) is connected to a positive terminal of a voltage source and the
the cathode (an n side of the junction) to the negative. The diode conducts very little (it
it has very high resistivity) when the connection is reversed; thus, the name reverse
reverse biasing is implied. If the reverse bias is made very large (in excess of the manufacturer
manufacturer specified limit), the reverse leakage current abruptly increases (the breakdown
breakdown effect), which often may lead to a catastrophic deterioration of detecting properties
properties or to the device destruction.[1].

• What types of physical effects and energies are involved in the sensing and in transformation?

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