Observatorio de I+D+i UPM

Memorias de investigación
Ponencias en congresos:
Analysis of wavelength influence on a-Si crystallization processes with nanosecond laser sources
Año:2012
Áreas de investigación
  • Ingenierías
Datos
Descripción
Laser assisted crystallization and annealing, as a process to produce polycrystalline thin films from amorphous-silicon (a-Si), has been the preferred method for polycrystalline thin-film formation for a number of relevant applications in microelectronics including thin film transistor fabrication. Additionally this topic has emerged again, hand in hand with the impressive growth of laser market in photovoltaic, as a potential solution for polysilicon formation in photovoltaic applications, due of course to the well known effect that grain size has been shown to have on the efficiency of polycrystalline cells. In this particular application, the wide range of different conditions (laser source type, wavelength, pulse width) in which good results in laser annealing of amorphous silicon has been proved, open the door of additional fundamental research of this topic, specially if this research is focused on developing useful information ready to be implemented in production plants. In this sense, laser pulsed annealing using DPSS lasers in the ns range is ideally suited for this purpose bearing in mind the intrinsic advantages that these lasers present for industrial production if compared with other alternatives as excimer or ultrafast lasers sources. In this work we present a detailed study of the wavelength influence in pulsed laser annealing of amorphous silicon thin films, comparing the results for material modification at different fluence regimes in the three fundamental harmonics of standard DPSS laser sources, UV (355 nm), visible (532 nm) and IR (1064 nm). For this study we have irradiated samples of amorphous silicon on glass (deposited by PCVD) and characterized them with MicroRaman techniques for assessing the structural changes induced in the material and the spatial distribution of the different material phases. In order to understand completely the physical mechanisms involved in the process of pulsed laser annealing in the ns regime, a finite element numerical model (FEM) has been developed in COMSOL to simulate the process, and results of the numerical model are presented together with the experimental results, proving that the process can be easily predicted, with an essentially physical model based on heat transport, at different wavelengths and fluence regimes.
Internacional
Si
Nombre congreso
E-MRS Spring 2012 Symposium V. Laser materials processing for micro and nano applications.
Tipo de participación
960
Lugar del congreso
Estrasburgo (Francia)
Revisores
Si
ISBN o ISSN
CDP08UPM
DOI
Fecha inicio congreso
14/05/2012
Fecha fin congreso
18/05/2012
Desde la página
1
Hasta la página
1
Título de las actas
E-MRS Spring 2012 Full Program Symposium V. Laser materials processing for micro and nano applications. Publicación electrónica en la web del congreso http://www.emrs-strasbourg.com/
Esta actividad pertenece a memorias de investigación
Participantes
  • Autor: Oscar Garcia Garcia (UPM)
  • Autor: Juan José García-Ballesteros . (UPM)
  • Autor: Sara Núñez Sánchez (UPM)
  • Autor: Miguel Morales Furio (UPM)
  • Autor: Carlos Luis Molpeceres Alvarez (UPM)
Grupos de investigación, Departamentos, Centros e Institutos de I+D+i relacionados
  • Creador: Grupo de Investigación: Grupo de Investigación en Ingeniería y Aplicaciones del Láser
  • Centro o Instituto I+D+i: Centro Laser
  • Departamento: Física Aplicada a la Ingeniería Industrial
S2i 2021 Observatorio de investigación @ UPM con la colaboración del Consejo Social UPM
Cofinanciación del MINECO en el marco del Programa INNCIDE 2011 (OTR-2011-0236)
Cofinanciación del MINECO en el marco del Programa INNPACTO (IPT-020000-2010-22)