Effect of superlattice-like multilayer structure on ferroelectric BiFe0.97Cr0.03O3/BiFe1-xMnxO3 composite thin films

Pure bismuth ferrate thin films often have a high leakage conductance and low polarization, which has greatly limited the application of bismuth ferrate thin films in electron devices. Here, the low mismatch interface of the BiFe0.97Cr0.03O3/BiFe1-xMnxO3 (x = 0.01-0.09) superlattice-like multilayer composite thin films are constructed, and the high leakage current and false polarization phenomenon of BiFe0.97Cr0.03O3/BiFe1-xMnxO3 superlattice-like multilayer composite thin films are regulated by the interface composite. The BFC0.03O/BFM0.09O sample had the highest rectangles (1.18) with larger residual polarization value (82 mu C/cm(2)), lower coercive field (265.05 kV/cm) and the largest polarization turnover current (0.56 mA). The BFC0.03O/BFM0.09O sample mainly possessed 60 degrees domain structures by piezoresponse force microscopy (PFM). In addition, the relationship between the false polarization and the built-in electric field is analyzed, and the contribution of the built-in electric field caused by defects (E-bi) and the built-in electric field caused by strain gradient (E-flexo) to the total built-in electric field is further studied.

Automated summary

To address the limited application of pure bismuth ferrate thin films in electron devices, researchers constructed BiFe0.97Cr0.03O3/BiFe1-xMnxO3 superlattice-like multilayer composite thin films with a low mismatch interface. The high leakage current and false polarization phenomenon were regulated by the interface composite. The BFC0.03O/BFM0.09O sample exhibited the highest rectangles, larger residual polarization value, lower coercive field, and the largest polarization turnover current.