利用氧化鋅奈米結構作為光電元件之抗反射層

Abstract

由於一維奈米結構具有組成光電元件的可能性，近來此類結構吸引了廣大的興趣。此外，氧化鋅由於電性與光性的特殊性質誠為了近來研究的重要材料之一。但是，對於氧化鋅一維奈米結構與反射率之間相關的完整關係還未被清楚的研究。 我們成功控制水熱法中不同的成長參數得到不同形貌之氧化鋅奈米柱陣列，包含不同的長度以及不同的。我們利用此不同形貌之氧化鋅奈米柱陣列成功得到具有梯度變化的折射率的抗反射層。此抗反射層不只具有寬頻譜的良好抗反射特性，也具有全方向性與對於不同偏極化光的良好抗反射特性。最後，我們將此氧化鋅奈米柱陣列抗反射層應用於氧化鋅與矽基所結合的光電元件上，由於氧化鋅奈米柱陣列可以有效的降低表面反射率，所以光電元件無論在正偏壓亦或是負偏壓下都能夠有較高的光響應。

Recently, one-dimensional and quasi-one-dimensional nanostructures have attracted a great deal of attention due to their potential as building blocks for electronic and photonic novel devices. Moreover, ZnO is a potentially important material due to its electrical and optoelectronic characteristics. Nonetheless, the study on the morphologies of ZnO nanorods (NRs) on the reflectance was rarely addressed. In this work, length-controlled and alignment-controlled ZnO nanorod arrays (NRAs) on the Si(100) substrates were synthesized using the hydrothermal method. It was found that the reflectivity of Si substrates with ZnO NRAs was dramatically decreased over a wide range of the incidence wavelength. Besides, ZnO NRAs exhibit omnidirectional and polarization-insensitive AR characteristics. Finally, we apply the ZnO NRAs on the p-Si/n-ZnO photodiode. The responsivity of the Si/ZnO photodiode is enhanced at forward bias and reverse bias, which is considered to be due to reduced surface reflectance and nanostructure morphology.