Epitaxial Growth of GaAs Nanowires on Si for Optoelectronics

Keywords:
nanowire, GaAs, optoelectronics

Abstract:
Semiconductor nanowires (NWs) have been intensively studied recently as powerful and versatile building blocks for novel electronics and optoelectronics, while the growth of NWs are virtually substrate free and enables direction integration of III-V optoelectronic devices into CMOS and Si photonic systems. However, understanding the underlying growth mechanism and gaining rational control over the NW morphology and properties are crucial for practical use of NWs in devices and integrated systems. We report here the systematic studies of the dependence of epitaxial growth of GaAs NW on GaAs(111)B and Si(111) substrates as a function of substrate temperature, input precursor (TMG and AsH3) flow rates, V/III precursor ratio, time, etc. using metal organic chemical vapor deposition (MOCVD). GaAs NWs was found linearly dependent to growth time on both GaAs and Si substrates, while the growth rate is faster on Si. Both group III and V precursors flow rates affect the NW growth, while only group III flow rate defines the growth rate at high V/III ratio. Optimized morphology was achievable low temperature and high III/V ratios. Transmission electron microscope, cathodoluminescence, electrical transport, and the correlation will be also discussed.

Nanotech 2008 Conference Program Abstract