Emission wavelength tuning of porous silicon with ultra-thin ZnO capping layers by plasma-assited molecular beam epitaxy

다공성 실리콘 기판위에 Plasma-assisted molecular beam epitaxy으로 성장한 산화아연 초박막 보호막의 발광파장 조절 연구

Porous silicon (PS) was prepared by electrochemical anodization. Ultra-thin zinc oxide (ZnO) capping layers were deposited on the PS by plasma-assisted molecular beam epitaxy (PA-MBE). The effects of the ZnO capping layers on the properties of the as-prepared PS were investigated using scanning electron microscopy (SEM) and photoluminescence (PL). The as-prepared PS has circular pores over the entire surface. Its structure is similar to a sponge where the quantum confinement effect (QCE) plays a fundamental role. It was found that the dominant red emission of the porous silicon was tuned to white light emission by simple deposition of the ultra-thin ZnO capping layers. Specifically, the intensity of white light emission was observed to be enhanced by increasing the growth time from 1 to 3 min.