基于岛状多晶氧化锌薄膜的电泵浦紫外随机激光

Electrically pumped ultraviolet random lasing from island-like polycrystalline ZnO film

光电子集成是当前光电技术和信息工程领域的新趋势和研究热点,其中光源集成化和工艺相容性已成为制约其进一步发展和应用的关键问题。报道了一种设计简单的、可直接集成在硅衬底上面的激子型激光二极管器件和工艺。基于岛状多晶氧化锌薄膜构建了一个金属/绝缘体/半导体(Au/MgO/ZnO MIS)异质结器件。利用Si衬底与ZnO外延层之间天然的大晶格失配,诱导ZnO薄膜表面形成了高度无序的多晶岛状纳米结构,从而在异质结激活层(ZnO/MgO界面区域)形成了高度无序的折射率随空间变化的散射介质。这极大增强了光学散射,有利于获得低阈值的随机激射。文中这种简单的光源器件结构设计和制备工艺提供了一种自下而上的实现氧化锌基集成光电子器件的新思路。

Currently,optoelectronic integration(OEI)has been new trend and hot topic in the fields of optoelectronics technology and information engineering.Especially,light source integration and technology compatibility have hindered the development and application of OEI.In this work,a simple structure of electrically-pumped excitonic laser diode was rationally designed and fabricated,which could be directly integrated on Si substrate.An Au/MgO/ZnO metal-insulator-semiconductor(MIS)heterojunction device was constructed based on the island-like polycrystalline ZnO film.Ascribed to the large natural lattice mismatch between Si wafer and ZnO epitaxy layer,the heteroepitaxy growth induced highly-disordered polycrystalline island-like nanostructure on the surface of ZnO film.Thence,the active region(nearby ZnO/MgO heterojunction interface)yielded a strong scatter media due to the spatial variation of refractive index.It greatly enhanced optical scattering and favored a low-threshold random lasing.The simple device structure design and fabrication technology provide a feasible way towards the bottom-up ZnO based optoelectronic integration.