The versatile surface reconstruction mechanisms, tunable surface properties, and exceptional electron emission characteristics of SrTiO3 films have garnered significant research interest. In this study, SrTiO3 films were synthesized on n-Si(100) substrates via radio frequency magnetron sputtering. To evaluate the impact of thermal annealing, the as-deposited films underwent post-deposition annealing in an oxygen ambient at 600 °C, 800 °C, and 1000 °C for a duration of 2 h each. The structural, chemical, and secondary electron emission (SEE) characteristics of the SrTiO3 films were characterized as a function of their high thermal process. Post-deposition annealing induced a significant improvement in crystallinity, which directly correlated with a heightened SEE yield (SEY). Furthermore, composition analysis revealed a marked stoichiometric reconfiguration at the surface, with the Sr:Ti:O ratio evolving from 1:0.32:1.14 to 1:0.22:0.94, suggesting a move toward an Sr-O terminated surface. The Sr-O terminated surface inherent to these SrTiO3 films promotes efficient electron escape due to its reduced work function. Following a 1000 °C annealing process, the peak SEY undergoes a significant shift from 2.11 to 2.76, representing a thermal optimization of the SEE performance by approximately 30.8%. High-temperature annealing enhances the SEE performance of SrTiO3 films, validating their significant potential for electron multiplication applications. This study provides a scalable pathway for developing highly efficient SEE materials with optimized crystalline and surface properties.
Li et al. (Fri,) studied this question.