ABSTRACT

Metalorganic molecular beam epitaxial GaAsN layers grown on (001) GaAs substrates have been investigated by TEM and TED. TEM results show that lateral composition modulation occurs in the GaAs1-xNx layer (x < 6.75%). It is shown that increasing N composition leads to poor crystallinity. AFM results show that the surfaces of the samples experience a morphological change from faceting to islanding, as the N composition increases. Based on the TEM and AFM results, a simple model is given to explain the formation mechanism for the lateral composition modulation.