Growth and Investigation of $p-La_{2//3}Ca_{1//3}MnO_3$/n-Si Heterostructures

We report the fabrication and investigation of p-n diode structures based on thin hole-doped $La_{2//3}Ca_{1//3}MnO_3$ films grown on n-type silicon substrates. $La_{2//3}Ca_{1//3}MnO_3$ films with typical thickness of about 400 nm were prepared using pulsed laser deposition. Reflection high-energy electron diffraction measurements revealed polycrystalline quality of $La_{2//3}Ca_{1//3}MnO_3$ thin films on Si substrates. The surface roughness of $La_{2//3}Ca_{1//3}MnO_3$ films investigated by atomic force microscopy was found to be in the range of 25÷30 nm. Studies of electrical properties showed that $La_{2//3}Ca_{1//3}MnO_3$/Si heterostructures exhibit nonlinear asymmetric I-V characteristics both at room temperature and at 78 K. Furthemore, it was shown that these I-V dependences are sensitive to magnetic field, especially at lower voltages.