Plasma CVD of Amorphous AlN from Metalorganic Al Source and Properties of the Deposited Films

Abstract

AlN films have been successfully deposited by plasma CVD for the first time. Al was supplied by trimethyl Al (TMA) with H2 or N2 carrier gas, and N was supplied as NH3 through separate gas lines. The deposition rate depends upon the TMA supply, and is essentially independent of the NH3 flow rate. The composition of the deposited films was almost AlN, although a small amount of oxygen was always detected. A better film was obtained for the H2 carrier gas than for N2 carrier gas. X-ray diffraction profiles of the deposited films exhibited no crystalline AlN diffracting peaks, suggesting that the films are not crystallized, but the infrared and ultraviolet absorption spectra exhibited the presence of the Al–N bond (650/cm) and an optical band gap of 5.55 eV. The refractive index was about 1.9. These results suggest that the plasma-deposited films possess dominant AlN properties even though they are not crystalline.

Atomic Layer Epitaxy Growth of AIN Thin Films

“…Using an analogous etching procedure, results comparable with the present ones were obtained by Hagesawa et al [9] for their AIN films prepared from Al(CH3)3 and NH3 by plasma CVD at 300 "C. On the other hand, Gordon et al [l01 reported that their AlN films prepared from &@(CH3)&, and NH3 by atmospheric CVD in a temperature range 100 -500 "C were dissolved with an approximate rate of 100 nm min-l under identical etching conditions.…”

Structural and chemical analysis of annealed plasma-enhanced atomic layer deposition aluminum nitride films

“…Similar behavior has been demonstrated for sputtered and CVD AlN. 35,36 The change in the oxygen content likely reflects also on the density changes of the samples; the 1:1 flow samples have larger changes in the density. The effects on the refractive index are not as pronounced in either of the sample types and the total changes are in the range of a couple percent.…”

Fourier transform infrared diagnostics of gas phase reactions in the metalorganic chemical vapor deposition of aluminum from dimethylethylamine alane

“…Figure 2 shows the typical IR absorption spectrum of gas phase DMEAA in the cell. The peaks of Al-N (768 cm Ϫ1 ) 18,19 and Al-H (1793 cm Ϫ1 ) 20 are clearly seen in Fig. 2 and several peaks from DMEA are also shown.…”