Structure and Optical Properties of Silicon Nanocrystals Embedded in Amorphous Silicon Thin Films Obtained by PECVD
Por:
Monroy B.M., Remolina Millán A., García-Sánchez M.F., Ponce A., Picquart M., Santana G.
Publicada:
1 ene 2011
Resumen:
Silicon nanocrystals embedded in amorphous silicon matrix were obtained by plasma enhanced chemical vapor deposition using dichlorosilane as silicon precursor. The RF power and dichlorosilane to hydrogen flow rate ratio were varied to obtain different crystalline fractions and average sizes of silicon nanocrystals. High-resolution transmission electron microscopy images and RAMAN measurements confirmed the existence of nanocrystals embedded in the amorphous matrix with average sizes between 2 and 6 nm. Different crystalline fractions (from 12% to 54%) can be achieved in these films by regulating the selected growth parameters. The global optical constants of the films were obtained by UV-visible transmittance measurements. Effective band gap variations from 1.78 to 2.3 eV were confirmed by Tauc plot method. Absorption coefficients higher than standard amorphous silicon were obtained in these thin films for specific growth parameters. The relationship between the optical properties is d
Filiaciones:
Monroy B.M.:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Coyoacan 04510, DF, Mexico
Remolina Millán A.:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Coyoacan 04510, DF, Mexico
García-Sánchez M.F.:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Coyoacan 04510, DF, Mexico
Ponce A.:
Centro de Investigación en Química Aplicada, Boulevard Enrique Reyna Hermosillo no.140, Saltillo, 25290, Coahuila, Mexico
Picquart M.:
Departamento de Física, Universidad Autónoma Metropolitana Iztapalapa, A.P. 55-534, 09340 Iztapalapa, DF, Mexico
Santana G.:
Univ Nacl Autonoma Mexico, Inst Invest Mat, Coyoacan 04510, DF, Mexico
All Open Access, Gold
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