Non-Stoichiometric Layers of III/IV Semiconductors

摘要

The objective of this research project was the control of defect formation andthermal stability in non-stoichiometric GaAs thin layers. As rich GaAs offers unique device applications in layer isolation and optoelectronics because of its insulating capabilities after a thermal annealing and ultrafast time response in the THz range. The introduction of an optical temperature measurement, utilizing the diffuse reflectance spectroscopy enhanced the accuracy of the growth parameter determination, leading to a fairly reproducible growth. This enabled us to determine the limits of the low temperature growth, a saturation of the lattice dilation at low growth temperatures and/or high BEP ratios, and the onset of polycrystallinity and epitaxial columnar growth as is usually observed in the epitaxial growth of ceramics.