Phase diagram and dielectric behavior of Ba0.6Sr0.4TiO3 thin films grown on orthorhombic substrates

The evolution of interfacial microstructure of eutectic SnAgCu and SnPb solders on Al/Ni(V)/Cu thin films was investigated after various heat treatments. In the eutectic SnPb system, the Ni(V) layer was well protected after 20 reflow cycles at 220 °C. In the SnAgCu solder system, after 5 reflow cycles at 260 °C, the (Cu,Ni)6Sn5 ternary phase formed and Sn was detected in the Ni(V) layer. After 20 reflow cycles, the Ni(V) layer disappeared and spalling of the (Cu,Ni)6Sn5 was observed, which explains the transition to brittle failure mode after ball shear testing. The different interfacial reactions that occurred in the molten SnAgCu and SnPb systems were explained in terms of different solubilities of Cu in the two systems. The dissolution and formation of the (Cu,Ni)6Sn5phase were discussed on the basis of a Sn–Ni–Cu phase diagram. In the solid-state aging study of the SnAgCu samples annealed at 150 °C for up to 1000 h, the Ni(V) layer was intact and the intermetallic compound formed was Cu6Sn5 and not (Cu,Ni)6Sn5, which is the same as was observed for the eutectic SnPb system.

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Dielectric tunable characteristics of compositional-gradient BaTi1−xSnxO3 thin films

Journal of Advanced Dielectrics ◽

10.1142/s2010135x21500193 ◽

2021 ◽

Vol 11 (04) ◽

pp. 2150019

Author(s):

Chenjing Wu ◽

Manwen Yao

Keyword(s):

Thin Films ◽

Impedance Matching ◽

Sol Gel ◽

Temperature Stability ◽

Dielectric Behavior ◽

Compositional Gradient ◽

Dielectric Tunability ◽

Temperature Range ◽

Si Substrates ◽

Low Leakage

Compositional-gradient [Formula: see text][Formula: see text]O3 thin films on Pt(100)/Ti/SiO2/Si substrates are fabricated with sol–gel using spin coating. All of the structures of the prepared thin films are of single-phase crystalline perovskite with a dense and crack-free surface morphology. BTS10/15/20 thin film exhibits enhanced temperature stability in its dielectric behavior. The temperature coefficient of capacitance [Formula: see text] in the temperature range from [Formula: see text]C to [Formula: see text]C is [Formula: see text]C and that of [Formula: see text] in the temperature range from [Formula: see text]C to [Formula: see text]C is [Formula: see text]C. Furthermore, the thin films show low leakage current density and dielectric loss. High and stable dielectric tunable performances are found in BTS10/15/20 thin films: the dielectric tunability of the thin films is around 20.1% under a bias voltage of 8 V at 1 MHz and the corresponding dielectric constant is in the range between 89 and 111, which is beneficial for impedance matching in circuits. Dielectric tunability can be obtained under a low tuning voltage, which helps ensure safety. The simulated resonant frequency of the compositional-gradient BTS thin films depends on the bias electric field, showing compositional-gradient BTS thin films could be used in electrically tunable components and devices. These properties make compositional-gradient BTS thin films a promising candidate for dielectric tuning.

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Dielectric and Ferroelectric studies of Pb0.85La0.15TiO3 Thin Films on solution derived RuO2 Bottom Electrodes

MRS Proceedings ◽

10.1557/proc-672-o9.3 ◽

2001 ◽

Vol 672 ◽

Author(s):

S. Bhaskar ◽

S. B. Majumder ◽

P. S. Dobal ◽

S. B. Krupanidhi ◽

R. S. Katiyar

Keyword(s):

Thin Films ◽

Profile Analysis ◽

Sol Gel ◽

Dielectric Behavior ◽

Tangent Loss ◽

Film Electrode ◽

Secondary Phases ◽

Leakage Currents ◽

Low Leakage ◽

Electrode Interface

ABSTRACTSol-Gel derived Pb0.85La0.15TiO3 PLT15) thin films were deposited on solution derived RuO2/Si, RuO2/Pt/Si and Pt bottom electrodes. Dielectric, tangent loss, hysteresis, J-E, measurements were also carried out on these films. X-ray results established the single phase perovskite formation with no secondary phases of PLT15 thin film on these electrodes. PLT15 thin films on RuO2 bottom electrode showed relatively inferior ferroelectric and dielectric behavior as compared to Pt electrode. Low leakage currents (10-8 A/cm2 at 10 kV/cm) and the observed J-E characteristics have been attributed to poor film-electrode interface. Observed electrical and dielectric properties have been correlated with the film-electrode interface. The interface characteristics were further augmented by depth profile analysis using Auger Electron Spectroscopy.

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