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Pulsed laser deposition(PLD) 박막 증착법을 이용하여 hexagonal HoMn1 - xFexO3(x = 0.0, 0.05) 물질을 박막으로 Pt/Ti/SiO2/Si 기판 위에 증착하였다. 또한 x-ray diffraction(XRD), atomic force microscopy(AFM), scanning electron microscope(SEM), 및 x-ray photoelectron spectroscopy(XPS)를 통하여 박막의 결정학적 및 미세 구조를 분석하였고, conversion electron Mossbauer spectroscopy(CEMS)를 이용하여 자기적 특성에 관해 연구하였다. 결정구조는 hexagonal 구조로써 space group이 P63cm로 분석되었고, single crystal과는 달리 (110) 방향으로 우선 배향성을 가지고 증착되었다. HoMn0.95Fe0.05O3 박막의 경우 single crystal과 비교했을 때 hexagonal unit cell의 c0 축은 일정하나 a0 축은 다소 감소함으로 분석되었다. 이는 박막 증착에 사용된 Pt/Ti/SiO2/Si 기판과의 lattice mismatch 때문으로 해석된다. Fe가 미량 치환된 HoMn0.95Fe0.05O3 박막을 상온에서 CEMS 측정을 수행한 결과, HoMn0.9557Fe0.05O3 분말의 경우 magnetic TN이 72 K 부근이므로, 상온에서 doublet absorption spectrum이 관측되었고, 전기사중극자 분열값(quadrupole splitting; DEQ)이 1.62±0.01 mm/s로 비교적 큰 값을 가짐을 확인하였다.


The hexagonal HoMn1 - xFexO3 (x = 0.00, 0.05) thin films were prepared using pulsed laser deposition (PLD) method on Pt/Ti/SiO2/Si substrate. The microstructure and magnetic properties have been studied by x-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscope (SEM), x-ray photoelectron spectroscopy (XPS), and conversion electron Mossbauer spectroscopy (CEMS). From the analysis of the x-ray diffraction patterns, the crystal structure for all films was found to be a hexagonal (P63cm), which was preferentially grown along (110) direction. The lattice constant c0 of the film with x = 0.05 was close to that of single crystal, whereas lattice constant a0 with respect to single crystal shows a slight decrease. This difference of lattice parameters between film and single crystal was caused by the lattice mismatch between the film and Pt/Ti/SiO2/Si substrate. Conversion electron Mossbauer spectrum of HoMn0.95Fe0.05O3 thin film shows an asymmetry doublet absorption ratio at room temperature, which is due to the oriented direction of crystallographic domains. This is corresponding with analysis of x-ray diffraction. The quadrupole splitting (DEQ) at room temperature is found to be 1.62 ?0.01 mm/s. This large DEQ was caused by asymmetry environment surrounding Fe ion.