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The new-type silicon photomultiplier with high density of cells (HD-SiPM) was developed by DEPHAN for the task of analog detecting of short light pulses. In this work we have tested and compared with known references its responsivity, amplitude and time resolution by short laser pulses (442 nm) in a wide range of signal intensities. The results demonstrate, that the new detector could be interesting for Hi-Res Medical Imaging and other pulse detecting applications in nuclear science, especially those requiring combination of sensitivity, high speed and dynamic range from a small-area detector or an array element.

In this paper, we analyze the influence of the crosstalk level and the dynamic range on the basic characteristics of a silicon solid-state photomultiplier and demonstrate their importance for detecting of optical signals with backlight illumination, in particular, for LIDAR application. Experimental results obtained in the study of threshold and fluctuation parameters of detectors with different levels of crosstalk and dynamic range are presented. It is shown that the detector design combining a high dynamic range with a small crosstalk gives a noticeable advantage in such applications.

The specific aspects of SiGe:C HBT process and device simulation using TCAD are discussed. Cut-off frequency fT and collector junction breakdown voltage BVcbo dependences on carbon concentration in SiGe base area are investigated. The boron and carbon profiles in SiGe base are obtained to provide a trade-off between gain, cut-off frequency and break-down voltage. High values of fT × BVcbo product were achieved.

The modern SiGe HBT structure with shallow and deep trench isolation (STI and DTI) is analyzed from electrothermal standpoint using TCAD system. The electrical parameters β, fT, fmax, maximal temperature Tmax, and thermal resistance RTH are under consideration. TCAD simulation confirms the fact that the presence of STI and DTI in SiGe HBT structures gains the self-heating effect in comparison with traditional Si BJT structures, where DTI is not used. It is shown that for high power regimes (IC = 0.5–3 mA; VCE = 4–5 V) the set of electrical parameters β, fT, fmax significantly degrade, temperature Tmax can reach the critical values about 500 K, and the thermal resistance RTH increases thrice in HBT structure with STI and DTI. These results agree with published experimental data.