Speaker
Description
Metal organic vapor phase epitaxy (MOVPE) is commonly used to produce a single crystalline GaAsN thin films by using hydrogen gas as carrier gas, leading precursors to reaction chamber. By the way, hydrogen gas has a possibility to flammable, thus it is need to special treatment to avoid this problem. On the other hand, the nitrogen gas (N${_2}$) is chosen one instead of hydrogen gas because nitrogen gas is safer from flaming and it has lowering thermal conductivity. Structural and vibrational properties of GaAsN (0 < N < 5%) films grown using nitrogen gas as a carrier gas were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM) and Raman spectroscopy. Effects of nitrogen carrier gas on morphologies and nitrogen incorporation of GaAsN films, which have varied two conditions, 100% of hydrogen carrier gas and 50% of hydrogen carrier gas to nitrogen gas. The results show that using nitrogen gas is cause of shifted growth temperature by lowering thermal conductivity. As using hydrogen gas, nitrogen gas needs higher temperature. As a result, we can expand the growth window and establish further incorporation of N in the GaAsN samples.
