title: Characterization of doped amorphous silicon thin films through the investigation of dopant elements by glow discharge spectrometry: a correlation of conductivity and bandgap energy measurements.
abstract: The determination of optical parameters, such as absorption and extinction coefficients, refractive index and the bandgap energy, is crucial to understand the behavior and final efficiency of thin film solar cells based on hydrogenated amorphous silicon (a-Si:H). The influence of small variations of the gas flow rates used for the preparation of the p-a-SiC:H layer on the bandgap energy, as well as on the dopant elements concentration, thickness and conductivity of the p-layer, is investigated in this work using several complementary techniques. UV-NIR spectrophotometry and ellipsometry were used for the determination of bandgap energies of four p-a-SiC:H thin films, prepared by using different B(2)H(6) and SiH(4) fluxes (B(2)H(6) from 12 sccm to 20 sccm and SiH(4) from 6 sccm to 10 sccm). Moreover, radiofrequency glow discharge optical emission spectrometry technique was used for depth profiling characterization of p-a-SiC:H thin films and valuable information about dopant elements concentration and distribution throughout the coating was found. Finally, a direct relationship between the conductivity of p-a-SiC:H thin films and the dopant elements concentration, particularly boron and carbon, was observed for the four selected samples.
authors: Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, Julian Clavería, 8 33006 Oviedo, Spain; E-Mails: pascal@itma.es (P.S.); mrpereiro@uniovi.es (R.P.).
authors: Pascal
authors: P
authors: Sánchez
authors: Olaya
authors: O
authors: Lorenzo
authors: Armando
authors: A
authors: Menéndez
authors: Jose Luis
authors: JL
authors: Menéndez
authors: David
authors: D
authors: Gomez
authors: Rosario
authors: R
authors: Pereiro
authors: Beatriz
authors: B
authors: Fernández
mesh_terms: D001880:Boranes / Q000737:chemistry; D004553:Electric Conductivity; D005740:Gases / Q000737:chemistry; D006865:Hydrogenation; D008567:Membranes, Artificial; D012825:Silicon / Q000737:chemistry*; D012993:Solar Energy; D013056:Spectrophotometry, Ultraviolet; D019265:Spectroscopy, Near-Infrared
chemical_list: D001880:Boranes; D005740:Gases; D008567:Membranes, Artificial; D012825:Silicon