Simplifying the ternary phase diagram of a GaAsM (M:Au,Ag,Cu) system to pseudo binary phase diagrams allows for an analysis of necessary growth conditions for NW production.\cite{Duan_2000}\cite{Panish_1967} Conditions for growth using laser ablation were found to be \(800-1030^{\circ}C\), \(100-500\) Torr, \(Ar:H_{2} (95:5)\) with laser specifications of (\(\lambda\) = 1064nm; 10Hz pulse; 2.5 W power). GaAs have been synthesized with radius as small as \(1.5 nm\) using this laser ablation method.\cite{Duan_2000}

MOCVD is a technique that is very similar to the VLS described above. Au nanoparticles are deposited onto a semiconductor substrate surface to alloy and initiate growth of vapor phase group (III) and group (V) precursors, such as Ga(CH\(_{3}\))\(_{3}\) and AsH\(_{3}\). These precursors are used to decompose to the elements necessary to make the GaAs NW.\cite{Joyce_2011} \cite{Stringfellow_1999} After annealing the substrate to rid it of impurities it is cooled to between 350 and \(550^{\circ}C\). The group V flow rate is adjusted for growth and the group III precursors are fed to the reaction chamber to initiate growth. Growth times are generally between 30 seconds and 120 minutes, chosen according to the growth rate and the desired nanowire length. Upon completion of growth, the samples are cooled under group V overpressure.\cite{Joyce_2011}