Synthesis And Characterization Of Alpha-Alumina Films Via Combustion Chemical Vapor Deposition

alpha -Alumina films are useful for high-temperature, wear, and semiconductor device applications because of their good oxidation resistance, high hardness values, and electrical properties, a-Alumina films have been previously synthesized using techniques such as chemical vapor deposition, sol-gel, physical vapor deposition, and plasma spraying. This paper presents an alternative approach for producing high quality dense a-alumina coatings using a flame-assisted process called combustion chemical vapor deposition (CCVD). This process is an open atmosphere technique that does not require the use of a reaction chamber. In this work alumina films were grown on YSZ at temperatures ranging from 900 to 1500 degrees C. At lower temperatures only amorphous alumina was grown, but as the deposition temperature increased different alumina phases were formed. At 1100 degrees C, a thin highly crystalline phi -Al2O3 coating was formed. At temperatures higher than 1100 degrees C thick alpha -Al2O3 coatings were deposited on the YSZ. Coatings were characterized by scanning electron microscopy (SEM) and x-ray diffraction (XRD).