CHEMICAL-COMPOSITION OF AUV THIN-FILMS DEPOSITED AT 523-723 K USING DIMETHYLETHYLAMINE ALANE AND AMMONIA

We have investigated a process for depositing AW thin films at tempera tures less than 800 K via surface reactions between specially chosen p recursors. An Al precursor, dimethylethylamine alane (DMEAA, (CH3)(2)C 2H5N:AlH3) was used with ammonia (NH3), and the reactants were deliver ed to the growth surface in separate steps using an atomic layer growt h (ALG) process to promote film formation through a sequence of surfac e reactions. AIN thin films were deposited on Si(100), Si(111), Al2O3( 00.1), and Al2O3(01.2) substrates at 523-723 K using a range of proces s flow conditions. Auger and X-ray photoelectron spectroscopy were emp loyed to characterize the chemical composition of the films. These mea surements detected carbon and oxygen contamination at the surface and smaller concentrations in the bulk. In the high-resolution X-ray photo electron spectroscopy C(1s) data, binding energies for C-H and C-N spe cies were identified but no C-Al species were present. In the N(1s) da ta, N-O species were not detected, but chemically bonded H was present in the films as NH3-x (x = 0-2) species. The composition varied with process conditions, and the hydrogen content decreased in AlN films pr ocessed above 600 K.