Adoption of wide-bandgap microcrystalline silicon oxide and dual buffers for semitransparent solar cells in building-integrated photovoltaic window system. Issue 8 (August 2019)

• Record Type: Journal Article
• Authors: Yang, Johwa; Jo, Hyunjin; Choi, Soo-Won; Kang, Dong-Won; Kwon, Jung-Dae
• Is Part Of: Journal of materials science & technology. Volume 35:Issue 8(2019)
• Page Start: 1563
• Page End: 1569
• Publication Date: 2019-08
• Subjects: a-Si:H amorphous hydrogenated Si -- a-SiOx:H amorphous hydrogenated SiOx -- AZO aluminum-doped zinc oxide -- BIPV building-integrated photovoltaics -- DSSC dye-sensitized solar cell -- Eg bandgap energy -- EQE external quantum efficiency -- FF fill factor -- FOM figure of merit -- FTO fluorine-doped tin oxide -- Jsc short-circuit current density -- PCE photoconversion efficiency -- PE-CVD plasma-enhanced chemical vapor deposition -- p-μc-SiOx:H p-type microcrystalline hydrogenated SiOx -- R flow rate ratio of CO2/SiH4 -- RF radio-frequency -- Rs series resistance -- Rsh sheet resistance -- STSC semitransparent solar cell -- TCO transparent conducting oxide -- UV ultraviolet -- Voc open-circuit voltage -- Xc crystalline volume fraction; Microcrystalline silicon oxide -- Building-integrated photovoltaics -- Semitransparent -- Thin film -- Solar cells; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2019.03.041
• Languages: English
• ISSNs: 1005-0302

Abstract

Abstract: We focused on developing penetration-type semitransparent thin-film solar cells (STSCs) using hydrogenated amorphous Si (a-Si:H) for a building-integrated photovoltaic (BIPV) window system. Instead of conventional p-type a-Si:H, p-type hydrogenated microcrystalline Si oxide (p-μc-SiO x :H) was introduced for a wide-bandgap and conductive window layer. For these purposes, we tuned the CO2 /SiH4 flow ratio ( R ) during p-μc-SiO x :H deposition. The film crystallinity decreased from 50% to 13% as R increased from 0.2 to 1.2. At the optimized R of 0.6, the quantum efficiency was improved under short wavelengths by the suppression of p-type layer parasitic absorption. The series resistance was well controlled to avoid fill factor loss at R = 0.6. Furthermore, we introduced dual buffers comprising p-a-SiO x :H/i-a-Si:H at the p/i interface to alleviate interfacial energy-band mismatch. The a-Si:H STSCs with the suggested window and dual buffers showed improvements in transmittance and efficiency from 22.9% to 29.3% and from 4.62% to 6.41%, respectively, compared to the STSC using a pristine p-a-Si:H window.