Analysis of heteroepitaxial germanium on gallium arsenide grown by pulsed laser deposition

Interest in the pulsed laser deposition (PLD) technique now extends far beyond growth of multiple component oxides, the area in which it first proved itself. In particular, it shows promise as a viable technique for high-quality crystalline thin films on substrates with low thermal tolerance. In this paper, we report the PLD growth of single-crystal Ge on (100) GaAs substrates in the temperature range of 150-550 °C. In situ reflection high-energy electron diffraction shows the formation of a reconstructed surface after as few as two laser pulses, corresponding to approximately 4% monolayer coverage. Transmission electron microscopy confirms heteroepitaxial growth with good quality interfaces and smooth surfaces, despite the presence of oxygen and carbon impurities.