The analysis of the grain size (GS) vs. energy density of silicon films irradiated with long pulse (LP) (150-200 ns) excimer laser has revealed that the maximum GS achievable is limited to 250-350 nm. In general, maximum GS occurs when the so-called super lateral growth (SLG) mechanism is triggered (almost complete melting) and in short-pulse (30 ns) irradiated films the maximum GS can be well above 1 μm. In order to clarify this discrepancy between the SLG regimes observed with short and LP irradiations, we performed an experiment with a LP (170 ns) excimer laser (HERCULES), having opportunely profiled the energy density to a 'ramp' distribution. In this way it was possible to have a continuous energy distribution and by analysing the structural (SEM) and topographical (AFM) properties it was possible to produce an accurate picture of their dependence upon the laser energy density. We were able to identify the SLG regime, with GS up to 1.5 μm and energy window ΔE/E = 0.002, pointing out the difficulties in observing SLG in LP irradiations. © 2002 Elsevier Science B.V. All rights reserved.
All Science Journal Classification (ASJC) codes
- Surfaces, Coatings and Films
- Condensed Matter Physics
- Surfaces and Interfaces
Pecora, A., Carluccio, R., Mariucci, L., Fortunato, G., Murra, D., Bollanti, S., & Di Lazzaro, P. (2003). Observation of super lateral growth in long pulse (170 ns) excimer laser crystallization of a-Si films. Thin Solid Films, 427(1-2), 319 - 323. https://doi.org/10.1016/S0040-6090(02)01164-1