The VLS (vapor-liquid-solid) method is one of the promising techniques for growing vertical III-V compound semiconductor\r\nnanowires on Si for application to optoelectronic circuits. Heterostructures grown in the axial direction by the VLS method and\r\nin the radial direction by the general layer-by-layer growth method make it possible to fabricate complicated and functional threedimensional\r\nstructures in a bottom-up manner. We can grow some vertical heterostructure nanopillars with flat tops on Si(111)\r\nsubstrates, and we have obtained core-multishell Ga(In)P/GaAs/GaP nanowires with flat tops and their air-gap structures by using\r\nselective wet etching. Simulations indicate that a high-Q factor of over 2000 can be achieved for this air-gap structure. From\r\nthe GaAs growth experiments, we found that zincblende GaAs without any stacking faults can be grown after the GaP nanowire\r\ngrowth. Pillars containing a quantum dot and without stacking faults can be grown by using this method. We can also obtain\r\nflat-top pillars without removing the Au catalysts when using small Au particles.
Loading....