The BTO thin films grown with layer-by-layer annealing method sho

The BTO thin films grown with layer-by-layer annealing method show a preferential <100> orientation. The films annealed at both 650°C and 700°C show strong diffraction peaks along the <100> and <200> directions, with no sign of this website the secondary-phase silicate formation. It is evident from Figure 2b that the BTO films that are annealed after deposition of 120 nm of BTO (prepared by two to three spin coating and pyrolysis steps) show a stronger diffraction peak along the <110> direction (compared to the <100> direction). A comparison of the lattice parameters of the BTO film deposited on different buffer layers with bulk BTO crystal

is mentioned in Table 1. Table 1 Comparison of the BTO thin films deposited on different buffer layers with the bulk material Phase Source Method a = b (Å) c (Å) c/a ratio Tetragonal (p4mm) Our work Sol–gel 3.994 4.038 1.011 Tetragonal On MgO buffer layer [18] MOCVD 3.990 4.04 1.012 Tetragonal BTO ceramic [19] Chemical processing 3.998 4.022 1.0058 Tetragonal BTO single histone deacetylase activity crystal [20] Chemical processing 3.992 4.036 1.011 Microstructure and roughness measurements The SEM images of BTO thin films grown on silicon <100> substrates with selleck kinase inhibitor different thicknesses of the lanthanum oxynitrate buffer layer are presented in Figure 3. The films annealed

at 600°C (not shown) with buffer layers of different thickness are amorphous, and no distinct crystal grains are visible from the SEM measurements. Figure 3 SEM top view and cross-section images of BTO thin films. SEM top view of BTO films annealed at 700°C, with buffer layers of (a) 6 nm and (b) 7.2 nm. Cross-section images of the BTO film deposited at 700°C (c) deposited with a buffer layer of 6 nm as shown in (a) and (d) prepared with layer-by-layer annealing for each 30-nm layer, with a

buffer layer of 8.9 nm. Figure 3a,b shows the top surface view of BTO films annealed at 700°C, with buffer layers of thickness 6 and 7.2 nm, respectively. The presence of the well-defined polygonal crystal grains is visible, and it shows the complete transformation of the amorphous films into a perovskite phase. The presence of the intercrystal Urocanase voids in the BTO films (approximately 150 nm) deposited with buffer layers less than 6 nm is visible in Figure 3a,c. This increases the chance of electrical short circuit between the bottom ITO and the top evaporated Cr contact as we also experienced in the electrical measurements. However, the present work shows that the density of the intercrystal voids can be decreased to a great extent by increasing the thickness of the buffer layer to 7.2 nm. The films deposited with BTO seeding layers have further improved quality and appear to have a dense structure without the presence of pin holes (Figure 3d).

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