Choice of Optimum Photodetector

As expected, the overview of the existing photodetector types shows that none can satisfy in full the requirements listed in Table 1.2. Therefore, we proceed by the method of elimination. 

A comparison of the remaining two classes, photonic and thermal detectors, shows that their performance is similar from the point of view of the criteria presented in Table 1.2. The main advantage of photonic detectors is their response speed, and in the case of thermal detectors their room-temperature operation and relatively lower price. This means that each of these detector types can find a share of market where its will dominate. 

From the point of view of the D f parameter, not taking into account the other criteria, photonic detectors appear as a better choice. To be sure, microsystem technologies enable a simultaneous increase of both the speed and the detectivity of thermal detectors, but only up to a certain point. According to [6], not only that the maximum specific detectivity and the bandwidth of these devices are inversely proportional, but also the maximum attainable specific detectivity at room temperature is limited by integral radiation of the background, not only by its part covered by spectral sensitivity range of the detector, as is the case with photonic devices. The conclusion is that a photonic detector without cooling requirements would have a chance to approach nearer to the idealized device described in Sect. 1.3. 

This work is dedicated to an analysis of the possible improvements of the performance of photonic detectors with a goal to use them at room temperature and to approach them as much as possible to the previously described idealized IR detector element. The presentation is limited to photoconductive and photovoltaic intrinsic detectors, although for the most part it can be generalized to any type of 

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