Hot Wire CVD for thin film triple junction cells and for ultrafast deposition of the SiN passivation layer on polycrystalline Si solar cells

• Published in: Thin solid films 2008-01, Vol.516 (5), p.496-499
• Main Authors: Schropp, R.E.I., Franken, R.H., Goldbach, H.D., Houweling, Z.S., Li, H., Rath, J.K., Schüttauf, J.W.A., Stolk, R.L., Verlaan, V., van der Werf, C.H.M.
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Efficiency; Energy; Exact sciences and technology; HWCVD; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Multijunction; Natural energy; Photovoltaic conversion; Physics; Silicon nitride; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy; Stability; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Theory and models of film growth; Thin film structure and morphology
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2007.06.052

We present recent progress on hot-wire deposited thin film solar cells and applications of silicon nitride. The cell efficiency reached for μc-Si:H n–i–p solar cells on textured Ag/ZnO presently is 8.5%, in line with the state-of-the-art level for μc-Si:H n–i–p's for any method of deposition. Such cells, used in triple junction cells together with hot-wire deposited proto-Si:H and plasma-deposited SiGe:H, have reached 10.5% efficiency. The single junction μc-Si:H n–i–p cell is entirely stable under prolonged light soaking. The triple junction cell, including protocrystalline i-layers, is within 3% stable, due to the limited thicknesses of the two top cells. The application of SiN x :H at a deposition rate of 3 nm/s to polycrystalline Si wafer solar cells has led to cells with 15.7% efficiency. We have also achieved record high deposition rates of 7.3 nm/s for transparent and dense SiN x ;H. Hot-wire SiN x :H is likely to be the first large commercial application of the Hot Wire CVD (Cat-CVD) technology.