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Hydrogenated amorphous silicon carbide (a-SiC:H) can provide exceptional surface passivation essential for high-efficiency crystalline silicon solar cells. This thesis reports on the fundamental study of a-SiC:H films deposited using a novel deposition technique, DC saddle field PECVD, in contrast to the conventional industrial use of RF-PECVD. The growth conditions were optimized and correlated with passivating, structural, and optical characteristics. The lifetime has a strong dependency on deposition temperature and improves by over two orders of magnitude as the temperature increases; the maximum lifetime achieved in this work reached 0.5 ms. In addition, the Tauc optical gap can be increased from 1.7 eV to 2.3 eV by varying the precursor gas mixture ratio. Post-deposition annealing experiments demonstrate thermal stability of the samples deposited at 250 °C and in some instances shows improvement in passivation quality by a factor of two with a one-step annealing treatment at 300 °C for 15 minutes.

Abstract Silicon carbide is a versatile material amenable to variety of applications from electrical insulation to surface passivation, diffusion-barrier in optoelectronic and high-frequency devices. This research presents a fundamental study of a-SiC:H films with variable stoichiometries deposited using novel technique, DC saddle-field plasma-enhanced chemical-vapour deposition, a departure from conventional RF PECVD commonly used in industry. DCSF PECVD is an alternative technique for low temperature large area deposition. Stoichiometric a-SiC:H obtained by fine-tuning precursor gas mixture. Annealing up to 800oC showed no significant change in elemental composition; particularly indicating thermal stability at stoichiometry. Ellipsometry showed wide range of optical gaps whose maximum surpasses values reported in literature. Refractive index measured and change in values studied as function of increasing carbon content in the films. Also attainment of very smooth surface morphology for stoichiometric a-SiC:H films reported. Surface roughness of 1 nm rms demonstrated for films grown at temperature as low as 225oC.

Hydrogenated amorphous silicon carbide (a-SiC:H) can provide exceptional surface passivation essential for high-efficiency crystalline silicon solar cells. This thesis reports on the fundamental study of a-SiC:H films deposited using a novel deposition technique, DC saddle field PECVD, in contrast to the conventional industrial use of RF-PECVD. The growth conditions were optimized and correlated with passivating, structural, and optical characteristics. The lifetime has a strong dependency on deposition temperature and improves by over two orders of magnitude as the temperature increases; the maximum lifetime achieved in this work reached 0.5 ms. In addition, the Tauc optical gap can be increased from 1.7 eV to 2.3 eV by varying the precursor gas mixture ratio. Post-deposition annealing experiments demonstrate thermal stability of the samples deposited at 250 °C and in some instances shows improvement in passivation quality by a factor of two with a one-step annealing treatment at 300 °C for 15 minutes.

Abstract Silicon carbide is a versatile material amenable to variety of applications from electrical insulation to surface passivation, diffusion-barrier in optoelectronic and high-frequency devices. This research presents a fundamental study of a-SiC:H films with variable stoichiometries deposited using novel technique, DC saddle-field plasma-enhanced chemical-vapour deposition, a departure from conventional RF PECVD commonly used in industry. DCSF PECVD is an alternative technique for low temperature large area deposition. Stoichiometric a-SiC:H obtained by fine-tuning precursor gas mixture. Annealing up to 800oC showed no significant change in elemental composition; particularly indicating thermal stability at stoichiometry. Ellipsometry showed wide range of optical gaps whose maximum surpasses values reported in literature. Refractive index measured and change in values studied as function of increasing carbon content in the films. Also attainment of very smooth surface morphology for stoichiometric a-SiC:H films reported. Surface roughness of 1 nm rms demonstrated for films grown at temperature as low as 225oC.

Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains ix, 69 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 55-63).

Thesis (Ph.D.)--McMaster University, 2004. / Supervisor: D.S. Wilkinson. Includes bibliographical references (leaves 164-170). Also available via World Wide Web.

Dissertation (Ph.D.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.111-116).

Dissertation (Ph.D.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.138-143).

Thesis (M.S.)--Missouri University of Science and Technology, 2008. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed August 27, 2008) Includes bibliographical references.