Photovoltaic and optoelectronic properties of InAs(100)-based photoconductive cells with quantum dots and nanopits

Investigation of InAsSbP quantum dot mid-infrared sensors

“…It can obviously be seen that the PCC, in comparison with the TIP, has a photoresponse spectrum extended to longer wavelengths up to 4 µm with a narrow peak at 3.48 µm. As was shown in our previous works, InAsSbP QDs grown on InAs form type-II band alignment (Gambaryan, 2010). The schematic of the band structure of the grown structure used for PCC in this work is presented in Figure 6.…”

“…We as- sume that opposite-directed oscillations revealed on the C-V curve occur due to the structure's total charge oscillations, which are caused by the depletion and occupation of the QDs' energy levels. Detected hysteresis can be explained by the remnant polarization in the structure due to spatial separation of the charge carriers in type-II InAsSbP QDs (Gambaryan et al, 2011) which are conserved after shutting off the voltage. For photoresponse measurements, a testing infrared photodetector (TIP) was fabricated and used.…”

“…In that work the grown structure was characterized by photoluminescence (PL) measurements at 4 K temperature and the PL peak at 1.65 µm was observed. Recently, InAsSbP QDs were successfully grown on InAs substrates as well (Gambaryan, 2010, andGambaryan et al, 2012). It was shown that using InAs substrates leads to the sensitivity in the mid-IR range (Gambaryan et al, 2011, and.…”

“…Recently, InAsSbP QDs were successfully grown on InAs substrates as well (Gambaryan, 2010, andGambaryan et al, 2012). It was shown that using InAs substrates leads to the sensitivity in the mid-IR range (Gambaryan et al, 2011, and. Among quantum-size object fabrication techniques, the self-organized Stranski-Krastanow (S-K) growth mode is an important one by which dislocationfree nanostructures can be produced (Stranski and Krastanov, Published by Copernicus Publications on behalf of the AMA Association for Sensor Technology.…”

“…. Depending on the growth conditions, the elastic strain can be relaxed by the formation of QDs, quantum rings or even unique island-pit pairs (Gambaryan, 2010 andGambaryan et al, 2012). In the S-K method, the last stage of nucleation in solid and liquid solutions is often characterized by the growth of the largest (supercritical) clusters and solving of small (subcritical) ones, which results in the decrease in the density of clusters with the increase in their sizes.…”