Low temperature GaAs has been grown by molecular beam epitaxy at substrate temperatures between 200 degrees C-400 degrees C, and subsequently annealed in the growth chamber at 600 degrees C. These samples have been characterized by X-ray and Raman spectroscopy. From the rocking curve of a high resolution double crystal X-ray diffraction system we observed that GaAs layers grown at low temperatures were highly strained and contained about 1% excess arsenic, These results have been compared with an analysis of LO and TO frequency splitting in the Raman spectra.
