Semiconducting nanowires rarely develop a protective coating in situ, leaving the surface vulnerable to defects and contaminants. By encapsulating them in the growth chamber with a stable compound, not only is the surface protected from environmental contaminants, but deleterious surface electronic states are minimized.
The invention involves a method for encapsulating semiconductor nanowires with inert carbon shells without modifying the nanowires’ electrical and optical properties, and the resulting structures. Key to the formation of ordered graphite shells is the presence of nanoclusters of metal on the surface of the nanowires. These metal clusters induce local formation of graphitic carbon in well-defined layers. The local carbon nuclei then continue to grow, spreading to uniformly cover the entire nanowire. The process takes place at moderate temperatures, 400?500°C, in the presence of sufficient carbon.
Applications and Industries
This process can be applied to any semiconducting nanostructure deposited in vacuum. The resulting passivated nanostructures can be used in electronic, optical, and mechanical devices.
The passivating layer reduces surface states that adversely affect semiconductor performance.