Mixed organic−inorganic halide perovskite solar cells (PSCs) are of interest for space photovoltaic applications due to their apparent tolerance to high-energy proton radiation. Here, the use of a more stable wide-bandgap FA 0.8 Cs 0.2 PbI 2.4 Br 0.6 Cl 0.02 perovskite with thin encapsulation enables, for the first time, the detailed dependence of fluence and energy of energetic protons on device performance. Energies were chosen to provide the highest concentration of displacements within the active region, and therefore the highest amount of degradation. Not only are these devices tolerant when compared to conventional technologies, but an unexpected increase in open circuit voltage and power density is observed for increased electronic ionization when the proton energy is increased. This study aims to expand the description of the proton radiation tolerance to include not only nonionizing nuclear energy losses that are most detrimental to current technologies, but electronic ionization, which is shown to yield benefits in PSCs.

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Low dimensional systems, nanowires (NWs), in particular, have exhibited excellent optical and electronic properties. Understanding the thermal properties in semiconductor NWs is very important for their applications in electronic devices. In the present study, the thermal conductivity of a freestanding silicon NW is estimated by employing Raman spectroscopy. The advantage of this technique is that the excitation source (laser) acts as both the heater and probe. The variations of the first-order Raman peak position of the freestanding silicon NW with respect to temperature and laser power are recorded. From the analysis of effective laser power absorbed by exposed silicon NW and a detailed Raman study along with the concept of longitudinal heat distribution in silicon NW, the thermal conductivity of the freestanding silicon NW of ∼112 nm diameter is estimated to be ∼53 W m−1 K− 1.

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Electron-beam deposited films of phosphosilicate (PSG) have been investigated as dielectrics for the encapsulation of Si-implanted GaAs for the purpose of post-implant annealing. The processing parameters that were optimized included the thickness of PSG film, the substrate temperature, and the annealing time and temperature. PSG films deposited at temperatures ≥300 °C showed no signs of deterioration up to temperatures in excess of 900 °C for 30-min anneals carried out in a forming gas and/or nitrogen ambient. Depth profiles in excellent agreement with the Lindhard–Scharff–Schiott curves were obtained with 1000-Å-thick films when annealed at 850 °C for 30 min. The diffusion coefficient of implanted silicon was found to be an order of magnitude smaller for the PSG films than that for the conventional plasma assisted chemical vapor deposited SiO2 films at 850 °C.