Thin Solid Films, Vol.570, 486-489, 2014
Microstructure, crystallization kinetics and recording characteristics of Si/NiSi bilayer for write-once blu-ray disk
In this study, the Si/NiSi (3 nm/16 nm) bilayer was prepared by sputtering at room temperature to employ as the recording film for write-once blu-ray disk. The thermal properties, crystallization mechanisms and recording characteristics were all investigated in detail. The composition of the NiSi alloy layer was fixed at Ni31Si\(69). From the result of reflectivity-temperature measurements, it was found that the Si/NiSi bilayer possessed two temperature ranges of reflectivity change, i.e. 156-200 degrees C and 330-350 degrees C. Microstructural analysis indicated that the NiSi2 nano-crystalline phase was formed in the as-deposited state. After annealing at 270 degrees C, the nano-crystallization Si was formed. Upon further increasing the annealing temperature to 500 degrees C, the crystallinity of Si was enhanced due to its re-crystallization. Dynamic tests reveal that the blu-ray disk with Si/NiSi recording layer has optimum jitter values of 7.5% and 8% at 1x and 2x writing speeds, respectively. This indicates that the Si/NiSi bilayer has high potential for the application of write-once blue laser recording media. (C) 2014 Elsevier B. V. All rights reserved.