Carbon incorporation process in GaAsN films grown by chemical beam epitaxy using MMHy or DMHy as the N source

Crystal quality of GaAsN films can be improved by using CBE for low-temperature growth. However, low-temperature growth increases C incorporation in the films, which degrades their electrical properties. Consequently, C incorporation was investigated in view of the surface reaction of N sources on a substrate surface, and MMHy and DMHy were compared. When MMHy was used as an N source, C concentration in GaAsN drastically increases below 380 °C than that in GaAs due to insufficient CHx desorption. In the case of DMHy, N(CH3)2 is desorbed more readily than CHx, therefore, the C concentration can then be reduced using DMHy.