Formation of MoSi2 by rapid thermal annealing in vacuum of CVD-Mo films onsilicon substrate

Silicide formation due to thermal treatment of thin (200-1000 Angstrom) mol ybdenum films on single-crystal silicon substrates in the temperature range of 800-1000 degrees C was studied. Rapid thermal annealing (RTA) in vacuum was performed on Mo/Si system to form silicides. Molybdenum films were dep osited on Si (1 0 0) by chemical vapor deposition (CVD), using Mo(CO)(6) (m olybdenum hexacarbonyl) as precursor. The as-deposited films with thickness es of 200 and 1000 Angstrom were heated in vacuum at RTA temperatures of 80 0 and 1000 degrees C for time durations of 15 and 30 s, 1 and 3 min. The re sults from the X-ray diffraction analysis and the Reflection Infrared Spect roscopy measurements show that Mo films after annealing transform into Mo s ilicides, preferably tetragonal MoSi2 crystal phase. The presence of Mo5Si3 formation is also found. There is a change in the electrical resistance of the films before and after annealing, For the molybdenum silicides obtaine d the resistivity is in the range 0.9-9.8 m Omega cm. (C) 2000 Elsevier Sci ence Ltd. All rights reserved.