Electrical Properties of RF-Sputtered FeSix Films and Their Relationship to Phase Transition from Im-FeSi to I2-FeSi2 during Post-Annealing

FeSix films were deposited on Si (100) substrates by RF-sputtering method using an FeSi2 target and post-annealing was carried out at temperatures in the range of 400-900 degree C for 1~h in Ar ambient. Sheet resistance of the deposited films was measured by four-point probe method and crystallinity of the films was analyzed by X-ray diffraction (XRD) measurement. Sheet resistance and XRD measurements revealed that the Fe atoms near the FeSix/Si interface were diffused towards Si substrate and the bottom of the deposited film gradually transformed to I2-FeSi2 with increasing the annealing temperatures although the FeSix films annealed at temperatures from 500 degree C to 800 degree C contained both Im-FeSi and I2-FeSi2. The film annealed at 900 degree C was completely transformed I2-FeSi2. [DOI: 10.1380/ejssnt.2012.190]