In situ grown size-controlled silicon nanocrystals: A p type nanocrystalline-Si:H/a-SiCx:H superlattice (p-nc-Si:H/a-SiCx:H) approach

• Published in: Solar energy materials and solar cells 2014-04, Vol.123, p.228-232
• Main Authors: Ma, Jun, Ni, Jian, Zhang, Jianjun, Liu, Qun, Hou, Guofu, Chen, Xinliang, Zhang, XiaoDan, Zhao, Ying
• Format: Article
• Language: English
• Subjects: Amorphous silicon; Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Energy; Exact sciences and technology; In situ grown; Natural energy; Photoelectric conversion; Photovoltaic conversion; Quantum confinement effects; Quantum dot superlattice; Solar cell; Solar cells. Photoelectrochemical cells; Solar energy
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2014.01.031

In situ grown p-nc-Si:H/a-SiCx:H quantum dot superlattice has been prepared by RF-PECVD at a low temperature of 150°C using layer by layer technique. This preparation method for fabricating superlattice allows controlling the properties of Si quantum dots in potential wells and the characteristics of potential barrier without subsequent annealing treatment, which is fully compatible with thin film Si technologies. High resolution transmission electron microscopy investigations confirm the superlattice structure of silicon quantum dots (~2nm diameter) separated by a-SiCx:H matrix (2–3nm thickness) with several periods. Strong room-temperature photoluminescence and the blue-shift of the PL peak position with increasing barrier height are indicative of quantum confinement effects. Applying p-nc-Si:H/a-SiCx:H superlattice as window layers, high open circuit voltage (>0.99V) was achieved for n–i–p type a-Si:H single junction solar cells. •In situ grown p-nc-Si:H/a-SiCx:H quantum dot superlattice has been prepared.•The structural characteristics and quantum confinement effects were investigated.•n–i–p type a-Si:H solar cell with Voc=0.99V was obtained at 150°C.