Electronic structure change with Gd doping of HfO2 on silicon, The
journal contributionposted on 26.09.2007, 00:00 by Ya. B. Losovyj, Ihor Ketsman, A. Sokolov, K. D. Belashchenko, P. A. Dowben, Jinke Tang, Zhenjun Wang
Gd-doped HfO2 films deposited on silicon substrates undergo a crystallographic change from monoclinic to fluorite cubic phase with increasing Gd concentrations. The crystallographic phase change is accompanied by a small increase in the valence bandwidth and in the apparent band offset in the surface region. Electrical measurements show pronounced rectification properties for lightly doped Gd:HfO2 films on p-Si and for heavily-doped Gd:HfO2 films on n-Si, suggesting a crossover from n-type to p-type behavior with increasing doping level.