The effects of ion doses on the properties of boron implanted Si for n-type solar cell application were investigated with doses ranging from 5×10^14cm^-2 to 2×10^15cm^-2 and a subsequent two-step annealing process in a tube furnace.With the help of the TCAD process simulation tool, knowledge on diffusion kinetics of dopants and damage evolution was obtained by fitting SIMS measured boron profiles. Due to insufficient elimination of the residual damage, the implanted emitter was found to have a higher saturation current density（J0e） and a poorer crystallographic quality. Consistent with this observation, V oc, J sc, and the efficiency of the all-implanted p^＋–n–n^＋solar cells followed a decreasing trend with an increase of the implantation dose. The obtained maximum efficiency was 19.59% at a low dose of 5×10^14cm^-2. The main efficiency loss under high doses came not only from increased recombination of carriers in the space charge region revealed by double-diode parameters of dark I–V curves, but also from the degraded minority carrier diffusion length in the emitter and base evidenced by IQE data. These experimental results indicated that clusters and dislocation loops had appeared at high implantation doses, which acted as effective recombination centers for photogenerated carriers.
The influence of sintering temperatures on solution-processed cadmium telluride （CdTe） nanocrys- tal films is studied in order to maximize the performance of CdTe/Al Schottky nanocrystal solar cells. The best overall performance of 2.67% efficiency at air mass 1.5 was achieved from devices with CdTe films sintered at 350 ℃ X-ray diffraction, scanning electron microscopy and UV-vis absorption measurements show that the CdTe nanocrystal grains began to grow remarkably well when sintering temperatures increased to 350 ℃. By analyzing the current-voltage characteristics, we find that the short-circuit current densities of devices increase with sintering temperatures ranging from 200 to 400 ℃, but, the over-sintered （450 ℃） treatment induces the shunting of devices.
