Comprehensive analysis of blue diode laser-annealing of amorphous silicon films

ABSTRACTThe deposition temperature of hydrogenated amorphous silicon films deposited by dc glow discharge was found to affect the photoresponse (ratio of the photo to dark conductivity) after crystallization of the film. This effect depended on the crystallization technique. For crystallization by laser annealing, the photoresponse (0.15 - 1.5) increased with increasing deposition temperature (150 - 300 °C) due to the increase in SiH and SiH2 bonding, as shown by infrared spectroscopy. For crystallization by furnace annealing (e.g. 650 °C, 50 h), the photoresponse (0.08 - 0) decreased with increasing deposition temperature (150 - 300 °C) due to the decrease in grain size and crystallinity as shown by x-ray diffraction; the complete loss in hydrogen during furnace annealing made the photoresponse low and the silicon-hydrogen bonding effect immaterial. Thus, laser crystallization at the highest deposition temperature gave the highest photoresponse.

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Structural change induced by laser annealing in hydrogenated amorphous silicon films

Journal of Non-Crystalline Solids ◽

10.1016/0022-3093(89)90499-7 ◽

1989 ◽

Vol 112 (1-3) ◽

pp. 85-89

Author(s):

Boqiang Zhong ◽

Zhongqian Lu ◽

Renye Tang

Keyword(s):

Structural Change ◽

Amorphous Silicon ◽

Laser Annealing ◽

Hydrogenated Amorphous Silicon ◽

Silicon Films ◽

Hydrogenated Amorphous

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Laser-induced graphitization of polydopamine leads to enhanced mechanical performance while preserving multifunctionality

Nature Communications ◽

10.1038/s41467-020-18654-8 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Kyueui Lee ◽

Minok Park ◽

Katerina G. Malollari ◽

Jisoo Shin ◽

Sally M. Winkler ◽

...

Keyword(s):

Mechanical Properties ◽

Diode Laser ◽

Laser Annealing ◽

Mechanical Performance ◽

Conformal Coating ◽

Inorganic Substrates ◽

High Roughness ◽

Functional Versatility ◽

Blue Diode Laser ◽

Better Than

Abstract Polydopamine (PDA) is a simple and versatile conformal coating material that has been proposed for a variety of uses; however in practice its performance is often hindered by poor mechanical properties and high roughness. Here, we show that blue-diode laser annealing dramatically improves mechanical performance and reduces roughness of PDA coatings. Laser-annealed PDA (LAPDA) was shown to be >100-fold more scratch resistant than pristine PDA and even better than hard inorganic substrates, which we attribute to partial graphitization and covalent coupling between PDA subunits during annealing. Moreover, laser annealing provides these benefits while preserving other attractive properties of PDA, as demonstrated by the superior biofouling resistance of antifouling polymer-grafted LAPDA compared to PDA modified with the same polymer. Our work suggests that laser annealing may allow the use of PDA in mechanically demanding applications previously considered inaccessible, without sacrificing the functional versatility that is so characteristic of PDA.

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