The feasibility of graphoepitaxial growth of compound semiconductors has been studied. Two kinds of substrates were prepared: a flat substrate, and a substrate with a periodic structured substrate. ZnO crystals were formed on both substrates by using thermal evaporation of elemental Zn and natural oxidation. Thermal treatment was performed to form large single-crystal domains. $X$-ray diffraction (XRD), atomic force microscope (AFM), and photoluminescence (PL) were used to characterize the samples. The periodic structure was found to have a strong influence on the size of the single-crystal domains in terms of the restriction of the surface migration length. Also, crystallographic orientations were affected by the periodic structure because both the sidewall and the bottom influenced the orientations of the single-crystal domains. A remarkable improvement in the crystallization was observed in terms of the PL linewidth, However, in the case of substrates with a periodic structured, interdiffusion of impurity the substrate was enhanced due to large surface area.
격자구조를 형성시킨 Si 기판상에 ZnO 박막을 graphoepitaxy 법으로 형성시켜 광학적인 특성과 구조적 특성을 평가하였다. 먼저 Si(100) 기판상에 노광작업을 이용하여 요철구조를 형성시켰다. 제작된 요철구조 위에 열증착 법으로 Zn를 증착시킨 후, 이를 산화시켜서 ZnO 박막을 형성시켰다. 또한 열처리에 의한 결정성의 변화를 관찰하기 위하여 700 $\sim$ 800 $^\circ$C에서 열처리를 하였다. 제작된 시료는 $X$ 선 회절법으로 ZnO 결정이 성장되었음을 알 수 있었고, Atomic Force Microscope (AFM)로 표면을 관찰한 결과 직육면체 형상의 ZnO결정이 관찰되었고, Photoluminescence (PL)을 이용하여 양호한 결정성을 가지고 있음을 확인하였다.
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