Large low-field magnetoresistance observed in twinned La2∕3Ca1∕3MnO3 thin films epitaxially grown on yttria-stabilized zirconia-buffered silicon on insulator substrates

Abstract

La 2 ∕ 3 Ca 1 ∕ 3 MnO 3 thin films have been grown on yttria-stabilized zirconia (YSZ) buffered silicon-on-insulator (SOI) substrates by the pulsed laser deposition technique. While full cube-on-cube epitaxy was achieved for the YSZ layer, the top manganite layer was multioriented in plane, with a coexistence of cube-on-cube and cube-on-diagonal epitaxial structures. Due to a combined influence from the magnetocrystalline, shape, and stain-induced magnetic anisotropy, in zero field and low temperatures the local spin orientation varies across the large-angle grain boundaries. As a result, a quite large low-field magnetoresistance (LFMR) based on spin-dependent tunneling was observed. The film shows a resistance change of ∼20% in a magnetic field <1000Oe at 50K, which is promising for real applications.

Effect of in situ stress on grain growth and texture evolution in sputtered YSZ/Si films

“…16 YSZ is stable against the formation of native oxide of silicon 17 and hence had been chosen as a buffer layer for the integration of lms of different oxides. 18,19 It is very important to note that most of the properties of oxides are anisotropic in nature. 20,21 As a result, highly oriented polycrystalline lms exhibit better physical parameters than their randomly oriented counterpart.…”

“…Oriented or textured YSZ buffer layers are achieved either by pulsed laser deposition, or by modied sputtering such as ultra-high vacuum ion sputtering and metallic target sputtering. 18,19,[22][23][24][25][26] However, the sputtered YSZ lms are in general polycrystalline and there are few reports of textured YSZ lms on Si by sputtering. 16,[27][28][29][30][31] Additionally, there are very few reports to the best of our knowledge on the quality of textured YSZ lms on Si as determined by using rocking curve.…”

“…Films with FWHM as low as 1 have been obtained by pulsed laser deposition. 18,34 However, in comparison to sputtering, it is more difficult to deposit uniform thin lms over large areas by PLD. Though the effect of stress on grain growth has been studied for metals, this is the rst report on correlation between stress, grain-growth and texture-evolution in oxide lm.…”

Growth of YBa2Cu3O7−δ and La0.67Ca0.33MnO3 thin films on silicon-on-insulator substrates

“…3. The resistance change is about 20% at 50 K in a magnetic field $700 Oe, which is promising for real applications [5]. The inset shows the SEM photograph of the LCMO thin film with a coexistence of cube-on-cube and cube-on-diagonal epitaxial structures in plane.…”

Nonlinear current-voltage behavior and giant positive magnetoresistance in nonmagnetic Au/Yttria-stabilized zirconia/Si heterostructures

“…YSZ film was grown on the Sb heavily doped n-type ͑100͒ silicon substrate ͑0.02 ⍀ cm and 1 ϫ 10 17 cm −3 ͒ by pulsed laser deposition. 8 The oxygen pressure was set to 5 ϫ 10 −4 Pa and the substrate temperature was kept at 820°C during deposition. The energy density of the laser pulse was about 1.5 J / cm 2 and the repetition rate was 7 Hz.…”