Integration of epitaxial colossal magnetoresistive films onto Si(100) using SrTiO3 as a template layer

Abstract

We report on the integration of epitaxial colossal magnetoresistive La0.67Ba0.33MnO films on Si(100) semiconductor using SrTiO3 template layer by pulsed-laser deposition. X-ray diffraction reveals the superior quality of the manganite film that grows epitaxially on heteroepitaxially grown SrTiO3 template layer on Si substrate. The epitaxial films demonstrate remarkable surface morphology, magnetic transition and hysteresis, magnetoresistance, and ferromagnetic resonance, illustrating the ferromagnetic nature of the film and possible device applications at room temperature.

Magnetic properties of La0.6Sr0.4MnO3 thin films on SrTiO3 and buffered Si substrates with varying thickness

“…The substrate was loaded to the chamber using a load-lock facility attached to the chamber and heated in the chamber at a rate of 20°C / min just after the ultimate base pressure of Ͻ3 ϫ 10 −8 Torr to avoid the oxidation of the Si substrate before depositing STO, as described earlier. 17 The films were cooled at a cooling rate of 10°C / min in O 2 of 500 Torr partial pressure from the growth temperature down to 300°C, and then allowed to cool naturally to room temperature. The thickness of the film was precisely controlled by the number of pulses.…”

Ferromagnetic properties of epitaxial manganite films on SrTiO3∕Si heterostructures

“…X-ray diffraction ͑XRD͒ shows that the RBMO films grow epitaxially on STO buffered Si substrates. 23 The STO thickness was limited to only 20 nm. The film thickness and composition inferred from Rutherford backscattering ͑RBS͒ using 3 MeV He 4+ ions at an angle of 160°.…”

Mecanosíntese do composto BiFeO3

“…No processo de síntese pelo método convencional cerâmico, é comum a ocorrência de fases espúrias com íons Fe 2+ no sistema, tornando as amostras condutoras e as inviabilizando para as caracterizações ferroelétricas necessárias. Alguns estudos indicam que estas fases espúrias podem estar ocorrendo devido à temperatura de volatilização, 825 ºC, do precursor Bi 2 O 3 utilizado na síntese do BFO [9]. Assim, quando o composto é submetido a tratamentos térmicos a temperaturas superiores a 825 ºC [8,9] , com terras raras R = Gd ou Eu, foram sintetizados por moagem em altas energias.…”

“…Alguns estudos indicam que estas fases espúrias podem estar ocorrendo devido à temperatura de volatilização, 825 ºC, do precursor Bi 2 O 3 utilizado na síntese do BFO [9]. Assim, quando o composto é submetido a tratamentos térmicos a temperaturas superiores a 825 ºC [8,9] , com terras raras R = Gd ou Eu, foram sintetizados por moagem em altas energias. As amostras foram analisadas por difração de raios X, microscopia eletrônica de varredura e espectroscopia por energia dispersiva de raios X.…”