The effect of growth condition on the structure of 2H – AlN films deposited on Si(111) by plasma-assisted molecular beam epitaxy

Abstract

The effects of substrate cleaning, nitridation time, and substrate temperature in the range 800–1000 °C on the microstructure of AlN/Si(111) films grown by simultaneous plasma-assisted molecular beam epitaxy have been investigated. It has been demonstrated, using a combination of conventional and high-resolution transmission electron microscopy, that the interface structure, the film defect structure, and the film surface roughness are strongly related. The formation of single crystal 2H–AlN films with atomically flat surfaces occurs at 800 °C for conditions of 2.5 nm/min growth rate on very pure, atomically flat Si substrates.