Studies On The Synthesis And Properties Of Silicon Nanowire Heterojunction And Silicon Nanowire/Organic Hybrid Solar Cell

Silicon nanowire (SiNW) array based radial p-n junction solar cells havepotential advantages due to the light trapping effects of SiNWs and quickcharge collection of core-shell structure based radial p-n junction, which hasbeen one of the most attractive projects in the photovoltaic field.In this work,silicon nanowire arrays were successfully prepared through the metal-assistedchemical etching technique. The influences of the process conditions on theparameters of light-trapping structure and the antireflection properties werestudied.； Moreover, Ag/AZO/(n+)/(i)/c-Si(p)NW and SiNWs/PEDOT:PSShybrid radial p-n junction silicon nanowires solar cells were fabricated andthe effect of preparation processes on the performance of obtained cells werediscussed。The main contents and results are as follows：1) silicon nanowire arrays were successfully prepared by the metalassisted chemical etching technonogy. The impact of AgNO3concentration inthe etching solution and etching time on the distribution parameters of SiNWswere considered, silicon nanowire arrays with2.5%average reflectivity of inthe range of300-1100nm was obtained for the AgNO3concentration of0.02M and the etching time of10min.2) α-Si:H passivation layers were deposited on silicon nanowire arraysby PECVD method, and the effect of deposition time and plasma power onthe passivation quality was discussed. Furthermore, Si nanowire-based solarcells were fabricated, and the influence of α-Si:H passivation process on theefficiency of cells was studied. The results demonstrated that the highest opencircuit voltage of0.50V was obtained when deposited α-Si:H passivationlayers with the power of15W for30min on0.51μm-long nanowires.3) The n-type Si:H layers with different microstructures were preparedby PECVD. Then a ultrathin layer of Al2O3was deposited between n-typeSi:H and AZO to fabricate Si nanowire array-based solar cells with AZO/Si:H(n)/a-Si:H/c-Si(p) radial structures. When the phase of n-type Si:H layerstranslated from amorphous to a double phase structure, the short circuit current density was increased by16.2%. With0.77-nm-thick Al2O3, the shortcircuit current density and power efficiency increased by10.2%and6.8%,respectively.4) SiNWs/PEDOT:PSS hybrid solar cells were fabricated by spincoating.The influencing factors on the cells performance, including touch statusbetween SiNWs and PEDOT:PSS, annealing process of PEDOT:PSS andproperty of carrier collected layers, were initially investigated. Thoughfabricated cells had a relatively low efficiency, about0.24%, the conclusionsobtained would have some reference value for hybrid solar cells achievinghigher efficiency in the future.