The annealing temperature effect on the electrical properties of boron-doped hydrogenated amorphous silicon a-Si:H(B)

• Published in: Physica status solidi. C Vol. 7; no. 3-4; pp. 679 - 682
• Main Authors: Khelifati, N., Tata, S., Rahal, A., Cherfi, R., Fedala, A., Kechouane, M., Mohammed-Brahim, T.
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01.04.2010; WILEY‐VCH Verlag; Wiley
• Subjects: 61.43.Dq; 61.72.uf; 72.80.Ng; 73.61.Jc; 78.66.Jg; 81.40.Ef; Amorphous silicon; Annealing; Boron; Electrical conductivity; Electrical resistivity; Hydrogen storage; Resistivity; White light
• ISSN: 1862-6351; 1610-1642; 1610-1634; 1610-1642
• DOI: 10.1002/pssc.200982718

The effects of the boron incorporation on the physico‐chemical, optical and electric properties of hydrogenated amorphous silicon (a‐Si:H) films are presented. Boron‐doped hydrogenated amorphous silicon (a‐Si:H(B)) thin films were deposited by DC magnetron sputtering where silicon and boron are co‐pulverized. They are characterized by infrared, optical absorption and electrical conductivity measurements. The boron concentration varies between 1.3 1017 cm‐3 and 1.6 1022 cm‐3. The boron incorporation induced an increase in the refractive index and a decrease in the optical gap. This incorporation is followed by a decrease of the hydrogen film content, an improvement of the electrical conductivity under darkness (σd) with a decrease of its activation energy. These results can be related to the shift of the Fermi level towards the valence band due to boron doping, but then to a significant change of structural properties. The electrical measurements under white light showed that the incorporated boron conducts to a degradation of the light sensitivity of the films. Effect of annealing temperature on electrical conductivity also shows that boron atoms passivated by hydrogen can be activated from the annealing temperature through bridging Si‐H‐‐‐B bonds dissociation (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)