Title of article :
Laser crystallization of amorphous SiC thin films on glass
Author/Authors :
S. Urban، نويسنده , , Adam F. Falk، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2001
Pages :
6
From page :
356
To page :
361
Abstract :
Usually, crystalline SiC films are produced by high-temperature processes such as chemical vapor deposition combined with the conventional thermal annealing. These processing technologies have the disadvantage that large area low-cost materials such as glass cannot be used as substrates. Long-term high-temperature annealing, however, can be avoided by laser irradiation of amorphous SiC films. Amorphous SiC films 50–500 nm thick deposited by laser ablation were crystallized by a single shot of a KrF excimer laser (248 nm wavelength, 25 ns pulse duration). As observed by transmission electron microscopy (TEM), polycrystalline SiC with a grain size of 10–20 nm resulted. During laser annealing, the crystallization process was studied by time resolved reflection (TRR) measurements by means of a cw-He–Ne laser (633 nm wavelength). The TRR results lead to the conclusion that above a threshold of 250 mJ/cm2 amorphous SiC is melted during the laser irradiation. After approximately 50 ns, the melt solidifies to crystallites. This observation is in contradiction to the equilibrium-phase diagram of SiC in which no liquid phase occurs at ambient pressure. The observed melt may be a metastable phase with respect to the SiC crystal at any temperature under consideration.
Keywords :
Metastable phases , Silicon carbide , Laser crystallization
Journal title :
Applied Surface Science
Serial Year :
2001
Journal title :
Applied Surface Science
Record number :
997481
Link To Document :
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