In this project funded by the Advanced Materials Processing Program of the Chemistry Division and the Electronic Materials Program of the Division of Materials Research, Xiaoyang Zhu of Southern Illinois University will study the fundamental reaction dynamics underlying thermal- and laser-assisted/induced atomic-layer epitaxial (ALE) growth of III-V semiconductors, predominantly gallium arsenide (GaAs). Quantum-state resolved distributions of nascent gas-phase products (methyl radicals and molecular hydrogen) formed in situ during laser-ALE growth of GaAs. Experimental techniques include resonance-enhanced multiphoton ionization (REMPI) spectroscopy and time-of-flight mass spectroscopy (TOFMS). The energetic information carried by gas-phase species should help answer such important questions as the molecular basis for the macroscopic kinetics observed in ALE, the effect on growth kinetics of the evolving surface structure, the coupling and redistribution of photon energy, and other ALE pathways involving Ga- and As-containing gas-phase products. The proposed research will also be extended to ALE growth of other III-V compounds. %%% Gallium arsenide (GaAs) based semiconductors play a vital role in the development of the next generation of optoelectronic and digital instruments because of some of their attractive properties, such as high speed, (for example, for computational purposes) and desirable active wavelength (in the case of communications devices). However, the manufacture of GaAs-based semiconductors has been hindered in part by effective methods for forming the electronic devices. This project addresses some of the stumbling blocks in one of the most promising methods of depositing GaAs in order to find resolve some of the problems.
