Epitaxial growth of aluminum nitride on Si(111) by reactive sputtering

Abstract

We have studied growth of aluminum nitride (AlN) on Si(111) by ultra-high vacuum (UHV) reactive dc-magnetron sputtering under a mixture of Ar and N2 gases. As-grown films have been examined by x-ray diffraction, Auger electron spectroscopy (AES), and transmission electron microscopy (TEM). Results of x-ray diffraction show texturing with AlN [0001]//Si[111]. Complementary TEM examinations observe epitaxy of AlN on Si(111), with AlN[112̄0]//Si[22̄0]. The AlN/Si interface is sharp and flat. The lowest substrate temperature required to achieve epitaxy Tepi has been determined to be ∼600 °C. A dislocation density in AlN film grown at 700 °C has been estimated to be ∼3×1011/cm2.

Structure of AlN on Si (111) Deposited with Metal Organic Vapor Phase Epitaxy

“…Furthermore, the high temperatures allow the nuclei to homogeneously orient themselves with the Si substrate in a low energy configuration. This conclusion accounts for the results obtained with UHV deposition, where a reduction in growth temperature below a critical value produced an identical degradation of crystal structure to wire texture [3]. However, this temperature occurred at 700°C under UHV sputtering instead of the 1100°C found for the MOVPE deposition reported here and also by Watanabe et al [5].…”

“…Much of this work was done in ultra-high vacuum (UHV) using molecular beam epitaxy (MBE) or sputtering to produce the layers [3,4]. Single crystal films could be grown under optimized conditions.…”

In situ stress measurements during the MOCVD growth of AlN buffer layers on (111) Si substrates

“…However, in spite of the fact that buffer layers strongly impact the quality of the epilayers, there are very few studies [5] in the literature on the growth of the AlN buffer layer itself, other than to study its effect on the GaN epilayer. Data on growth stresses in nitrides are also scarce [2,3,[6][7][8][9]. On Si, ex situ post growth studies performed using Xray diffraction showed that the growth stresses are tensile with a value of +0.5 GPa in GaN grown on a high temperature (1100 C) AlN epilayer [9].…”

Growth temperature and N2 ambient pressure-dependent crystalline orientations and band gaps of pulsed laser-deposited AlN/(0001) sapphire thin films

“…Therefore, the fabrication of highquality c-axis-oriented AlN thin films is considered to be of high technological importance. A variety of deposition methods such as conventional chemical vapor deposition (CVD) [7], plasma-enhanced CVD [8], reactive DCmagnetron sputtering [9], metal-organic CVD [10], MBE [11], pulsed laser deposition (PLD) [12][13][14][15][16] etc. have been successfully used to grow AlN thin films.…”