This paper presents maps of spatial distributions of the short circuit current Isc(x,y) and the open circuit voltage Uoc(x,y) of the investigated low cost solar cells. Visible differences in values of these parameters were explained by differences in the serial and shunt resistances determined for different points of solar cells from measurements of I–V characteristics. The spectral dependence of the photo voltage of solar cell is also shown, discussed and interpreted in the model of amorphous and crystal silicon.

The method of cleaning the ISFET structures after application of a biological substance was developed. There are few references in the literature to cleaning methods of this type of structure for biological applications, but they are relatively complex and difficult to automate. We decided to use resources commonly available in technological laboratories and methods that could be relatively easily automated, which would enable the full potential of ISFET transistors to be used. During the experiments, both acetone and deionized water were tested. The cleaning method was modified and it was checked whether it is possible to use such a method on one transistor more than once and how it affects the transistor's detection capabilities. We managed to obtain an effective method of cleaning ISFETs from biological substances. This method does not allow for obtaining exactly the same state as the original state of the transistor, but it ensures its correct operation and determining the influence of the tested biological substance on the transistor based on the results.

A theoretical analysis of the mid-wavelength infrared range detectors based on the HgCdTe materials for high operating temperatures is presented. Numerical calculations were compared with the experimental data for HgCdTe heterostructures grown by the MOCVD on the GaAs substrates. Theoretical modelling was performed by the commercial platform SimuAPSYS (Crosslight). SimuAPSYS fully supports numerical simulations and helps understand the mechanisms occurring in the detector structures. Theoretical estimates were compared with the dark current density experimental data at the selected characteristic temperatures: 230 K and 300 K. The proper agreement between theoretical and experimental data was reached by changing Auger-1 and Auger-7 recombination rates and Shockley-Read-Hall carrier lifetime. The level of the match was confirmed by a theoretical evaluation of the current responsivity and zero-bias dynamic resistance area product (R0A) of the tested detectors.

Numerical analysis of the dark current (Jd) in the type-II superlattice (T2SL) barrier (nBn) detector operated at high temperatures was presented. Theoretical calculations were compared with the experimental results for the nBn detector with the absorber and contact layers in an InAs/InAsSb superlattice separated AlAsSb barrier. Detector structure was grown using MBE technique on a GaAs substrate. The k p model was used to determine the first electron band and the first heavy and light hole bands in T2SL, as well as to calculate the absorption coefficient. The paper presents the effect of the additional hole barrier on electrical and optical parameters of the nBn structure. According to the principle of the nBn detector operation, the electrons barrier is to prevent the current flow from the contact layer to the absorber, while the holes barrier should be low enough to ensure the flow of optically generated carriers. The barrier height in the valence band (VB) was adjusted by changing the electron affinity of a ternary AlAsSb material. Results of numerical calculations similar to the experimental data were obtained, assuming the presence of a high barrier in VB which, at the same time, lowered the detector current responsivity.

The mismatch effect of photovoltaic (PV) arrays due to different illumination intensity has a significant impact on the output characteristics and output power of PV arrays, which is crucial to understand the output characteristics of PV arrays and optimize the array configuration in order to improve the value of the maximum power point. This paper illustrates the short-circuit current mismatch of series circuits, and the open-circuit voltage mismatch of parallel circuits and proposes corresponding solutions for each mismatch phenomenon. The output characteristics of multi-stage series PV arrays and multi-stage parallel PV arrays under complex illumination are analyzed by using the peak point approximation calculation method, and the distribution law of peak voltage points as well as the I-V (Current-Voltage) characteristic equation of each operating section are proposed. On this basis, the output characteristics of 3 x 3 centralized PV arrays are analyzed and verified by simulation. By comparing series and parallel PV arrays with the same condition, as well as several groups of centralized PV arrays with the same topology and different types of illumination distribution, this paper proposes a configuration optimization method for PV arrays. Matlab/Simulink simulation results confirm that the output power of parallel arrays is greater than that of series arrays under the same configuration and illuminationt distribution type, and the peak point is less than that of series arrays under the same configuration and lighting conditions; while in centralized PV arrays, the fewer series modules are shaded, the greater the output power and the less the peak point.