RF 마그네트론 스퍼터링을 이용한 Bismuth 박막의 제조와 그 전기적 특성 연구

• Published in: Biuletyn Uniejowski Vol. 38; no. 1; pp. 7 - 13
• Main Authors: 김동호(Dong-Ho Kim), 이건환(Gun-Hwan Lee)
• Format: Journal Article
• Language: Korean
• Published: 한국표면공학회 2005
• Subjects: 기계공학; Bismuth; Hall effect measurement; Thermoelectric thin film; Sputtering
• ISSN: 1225-8024; 2299-8403; 2288-8403

Bismuth thin films were prepared on glass substrate with RF magnetron sputtering and effects of substrate temperature on surface morphology and their electrical transport properties were investigated. Grain growth of bismuth after nucleation and the onset of coalescense of grains at 393 K were observed with field emission secondary electron microscopy. Continuous thin films could not be obtained above 473 K because of grain segregation and island formation. Hall effect measurements showed that substrate heating yields the decrease of carrier density and the increase of mobility. Resistivity of bismuth film has its minimum (about 0.7 x 10/sup -3/ Ωcm) in range of 403～433 K. Annealing of bismuth films deposited at room temperature was carried out in a radiation furnace with flowing hydrogen gas. The change of resistivity was not significant due to cancellation of the decrease of carrier density and the increase of mobility. The abrupt change of electrical properties of film annealed above 523 K was found to be caused by partial oxidation of bismuth layer in x-ray diffraction analysis.