Ultrathin IBAD MgO films for epitaxial growth on amorphous substrates and sub-50  nm membranes

A fabrication process has been developed for high energyion beam assisted deposition (IBAD) biaxial texturing of ultrathin ( ∼1 nm) MgOfilms, using a high ion-to-atom ratio and post-deposition annealing instead of ahomoepitaxial MgO layer. Thesefilms serve as the seed layer forepitaxialgrowth of materials on amorphous substrates such as electron/X-ray transparent membranes or nanocalorimetry devices. Stress measurements andatomic force microscopy of the MgOfilms reveal decreased stress andsurface roughness, whileX-ray diffraction ofepitaxial overlayers demonstrates the improved crystal quality offilmsgrown epitaxially on IBAD MgO. The process simplifies the synthesis of IBAD MgO, fundamentally solves the “wrinkle” issue induced by thehomoepitaxial layer on sub-50  nm membranes, and enables studies ofepitaxial materials in electron/X-ray transmission and nanocalorimetry.

Source: Applied Physics Letters - November 9, 2016 Category: Physics Authors: Siming Wang, C. Antonakos, C. Bordel, D. S. Bouma, P. Fischer and F. Hellman Source Type: research