Influence of a-Si:H deposition temperature on thermal stability of a-Si:H/SiNx:H stacks


By C.C Huang, R&D Division, Motech Industries; Y.T. Huang, Department of Photonics, National Chiao Tung University; Y.W. Tseng, Department of Photonics, National Chiao Tung University; W.H. Chen, Motech Industries; T. Fang, R&D Division, Motech Industries; C.C. Li, R&D Division, Motech Industries; C.C. Tsai, Professor, National Chiao Tung University

A hydrogenated amorphous Si (a-Si:H) film, combined with a silicon nitride (SiNx:H) capping layer and a post-deposition anneal, can hugely enhance the surface passivation on crystalline silicon wafers. In this work, the influence of various deposition temperatures of a-Si:H films on the thermal stability of a-Si:H/SiNx:H stacks and a possible mechanism are discussed. Both minority carrier lifetime measurement and grazing-angle XRD were employed to study the thermal stability of a-Si:H/SiNx:H stacks, and the results are interpreted in terms of dihydrides concentration and epitaxial crystallization. With an appropriate thermal treatment, the a-Si:H film deposited at 130°C and capped by SiNx:H showed better passivation performance than 200°C-deposited a-Si:H/SiNx:H stacks, but under an excessive thermal budget the former showed more severe degradation of carrier lifetime. The more dihydride-rich composition within 130°C-deposited a-Si:H/SiNx:H stacks could be regarded as providing more effective intermediates for hydrogen interchanges, but on the other hand, it is also more susceptible to epitaxial crystallization.

Published In

The tenth edition of Photovoltaics International was published in November 2010. In this edition, Q-Cells SE demonstrates the benefits of laser marking, Fraunhofer IST presents TCO deposition techniques in Thin Films, and we take an in-depth look at the benefits of using selective emitters on an industrial scale with Neo Solar Power.

Read Next

Subscribe to Newsletter

Upcoming Events

Solar Media Events
March 12, 2024
Frankfurt, Germany
Upcoming Webinars
March 13, 2024
9am EDT / 1pm GMT / 2pm CET
Solar Media Events
March 19, 2024
Texas, USA