Structural and dielectric properties of BaTiO₃–Bi(Mg_1/2Ti_1/2)O₃thin films fabricated by chemical solution deposition

Abstract

Thin films of the BaTiO 3 -Bi(Mg 1/2 Ti 1/2 )O 3 (BT-BMT) solid-solution system were fabricated with the aim of achieving a stable temperature coefficient of capacitance (TCC) favorable for high-temperature electronics. A single perovskite phase with pseudocubic symmetry was obtained for the films fabricated by chemical solution deposition on (111)Pt/TiO 2 /(100)Si substrates in the composition range of x = 0-0.80 for (1 % x)BT-xBMT. BMT added to the BaTiO 3 -based films enhanced the crystallinity of the perovskite phase and resulted in saturated P-E hysteresis behavior with remanent polarization of up to 13 µC/cm 2 . BMT addition led to gradual dielectric relaxation, which also resulted in stable TCC behavior with a relative dielectric constant of approximately 400 in the temperature range of RT % 400 °C, especially for the BT-BMT films with x = 0.20-0.40.

Dielectric properties of BaTiO₃–Bi(Mg_1/2Ti_1/2)O₃ films with preferential crystal orientation

“…No drastic variation of the ¾ r and tan ¤ values depending on the temperature was confirmed for these films, while the ¾ r value of conventional BaTiO 3 film without BMT addition decreased drastically with increasing temperature above 100°C. 24), 25) Frequency dependence of the ¾ r value indicated in Fig. 4 was confirmed during the temperature range of R.T. ¹ 400°C, whereas it was also found for the bulk materials 31) especially below the phase-transition temperature.…”

“…Combination with other perovskite compounds, such as SrTiO 3 , revealed the relaxor-type ¾ r ¹ T behavior with higher ¾ r of up to 1500. Also in our research, thin-film capacitors of BTBMT solid solution were fabricated by pulsed laser deposition (PLD) 24) and chemical solution deposition (CSD), 25) which exhibited suppressed TCC behavior together with ¾ r = 4001000. These properties will be more suitable for constructing high-permittivity dielectric capacitors with stable performance against temperature changes, compared with those of conventional materials.…”

Solid-solution thin films of ternary BaTiO3–Bi(Mg1/2Ti1/2)O3–BiFeO3system epitaxially grown on SrRuO3//SrTiO3substrates via chemical solution process

“…The BT solution was prepared using (CH 3 COO) 2 Ba and Ti(O-n-C 4 H 9 ) 4 as starting materials and a mixture of 2-methoxyethanol and acetic acid (with volume ratio of 2-methoxyethanol : acetic acid ¼ 4:0 : 1:0) as a solvent. [12][13][14] The BMT solution was prepared using Bi(O-t-C 5 H 11 ) 3 , Mg(OC 2 H 5 ) 2 , and Ti(O-n-C 4 H 9 ) 4 as starting materi-als and 2-methoxyethanol as a solvent. The BF solution was prepared using Bi(O-t-C 5 H 11 ) 3 and Fe(acetylacetonate) 3 .…”

Crystal structure and polarization hysteresis properties of ferroelectric BaTiO3 thin-film capacitors on (Ba,Sr)TiO3-buffered substrates

“…11,12) The functions of these electronic devices rely primarily on the switching ability of ferroelectric polarization with application of electric fields. The thin-film properties of dielectric, piezoelectric, and polarization switching in perovskite ferroelectrics such as BaTiO 3 (BT), [13][14][15][16][17][18][19][20] Pb(Zr,Ti)O 3 , 2,[21][22][23][24][25][26][27] BiFeO 3 , [28][29][30][31][32][33][34][35][36][37][38][39][40] (K,Na)NbO 3 , [41][42][43][44][45] and their related materials [46][47][48][49][50][51][52][53][54][55] have been intensively studied. For basic research on BT thin films, SrTiO 3 (STO) single-crystal substrates were used to investigate the influence of misfit strain from the substrates.…”