Abstract
Well-crystallized ZnO nanoneedles were grown on Au-coated Si(100) substrate by cyclic feeding chemical vapor deposition (CFCVD) process using diethyl zinc and oxygen as precursors for zinc and oxygen, respectively. Morphological investigations revealed that the as-grown nanoneedles exhibited sharpened tips and wider bases, having the typical diameters at their bases and tips, 60 +/- 10 nm and 20 +/- 10 nm, respectively. Detailed structural characterizations confirmed that the as-grown products were single crystalline with a wurtzite hexagonal phase and were grown preferentially along the [0001] direction. The room-temperature photoluminescence (PL) spectrum showed a strong and sharp UV emission at 378 rim with a very weak, suppressed and broad green emission at 520 nm, substantiating good optical properties for the as-grown ZnO nanoneedles.