Selective area growth of GaInNAs/GaAs by MOVPE

Abstract

Selective area growth (SAG) of GaInNAs/GaAs systems has been studied by metalorganic vapor-phase epitaxy (MOVPE) for the first time. This also includes a comparative study of SAG of the GaInAs/GaAs. The patterns consisted of various filling factors (F). The band gap changes and the growth morphology have been investigated. A red-shift observed for SAG GaInAs is similar to100 nm with respect to the planar GaInAs which can be attributed to both In enrichment and quantum well (QW) thickness enhancement. Selectively grown GaInNAs structures exhibit a maximum wavelength of 1.3 mum, corresponding to a red-shift of similar to80 nm with respect to the planar GaInNAs. Atomic force microscopy (AFM) scans reveal a three-dimensional growth behaviour for SAG GaInNAs unlike SAG GaInAs. This can be related to a certain amount of phase separation or strain that are often the signatures of N incorporation. The cathodoluminescence (CL) intensities (spectral line width) for SAG GaInNAs are larger (smaller) than those for SAG GaInAs at low F's but smaller (larger) at high F's. This indicates that at low F's, GaInAs has degraded due to very high strain but certain amount of strain compensation occurs in GaInNAs.