An oxide-based resistance memory is a leading candidate to replace Si-based flash memory as it meets the emerging specifications for future memory devices. The non-uniformity in the key switching parameters and low endurance in conventional resistance memory devices are preventing its practical application. Here, a novel strategy to overcome the aforementioned challenges has been unveiled by tuning the growth direction of epitaxial brownmillerite SrFeO thin films along the SrTiO [111] direction so that the oxygen vacancy channels can connect both the top and bottom electrodes rather directly. The controlled oxygen vacancy channels help reduce the randomness of the conducting filament (CF). The resulting device displayed high endurance over 10 cycles, and a short switching time of ∼10 ns. In addition, the device showed very high uniformity in the key switching parameters for device-to-device and within a device. This work demonstrates a feasible example for improving the nanoscale device performance by controlling the atomic structure of a functional oxide layer.

No abstract

BiMnO 3 has been a promising candidate as a magnetoelectric multiferroic while there have been many controversial reports on its ferroelectricity. The detailed analysis of its film growth, especially the growth of thin film having monoclinic symmetry has not been reported. We studied the effect of miscut angle, the substrate surface, and film thickness on the symmetry of BiMnO 3 thin film. A flat SrTiO 3 (110) substrate resulted in a thin film with three domains of BiMnO 3 and 1 degree miscut in the SrTiO 3 (110) substrate resulted in dominant domain preference in the BiMnO 3 thin film. The larger miscut resulted in a nearly perfect detwinned BiMnO 3 film with a monoclinic phase. This strong power of domain selection due to the step edge of the substrate was efficient even for the thicker film which showed a rather relaxed growth behavior along the SrTiO 3 [1-10] direction.

No abstract

BiMnO 3 has been assumed to be a very rare example of multiferroic materials. But the growth of BiMnO 3 thin film with high quality itself was very challenging. So physical properties has been studied only marginally for this compound. Here we report the observation of resistance switching for twin free BiMnO 3 thin film which was grown with high quality on the miscut Nb-doped SrTiO 3 (110) substrate.