Integration of Biaxially Aligned Conducting Oxides with Silicon using Ion-Beam Assisted Deposited MgO Templates

摘要

Two conducting oxides, La_(0.5)Sr_(0.5)CoO_3(LSCO) and SrRuO_3, were deposited by pulsed laser ablation onto silicon substrates coated with biaxially textured MgO on an amorphous silicon nitride isolation layer. Comparison is made between templates using just 10 nm of ion-beam assisted deposited (IBAD) MgO and substrates with an additional 100 nm of homoepitaxial MgO. Both of these conducting oxide layers exhibited in-plane and out-of-plane texture, on the order of that obtained by the underlying MgO. The SrRuO_3 was c-axis oriented on both substrates, but exhibited a slightly sharper out-of-plane texture when the homoepitaxial MgO layer was included. On the other hand, the LSCO showed only (100) orientation when deposited directly on the IBAD-MgO templates, whereas a significant (110) peak was observed for films on the homoepitaxial MgO. A simple calculation of the distribution of grain boundary angles, assuming a normal distribution of grains, is also presented.