Synthesis and white photoluminescence of porous polysilicon

• Published in: Materials letters 2016-11, Vol.182, p.102-105
• Main Authors: Song, Yue Li, Sun, Xiao Jun, Li, Yong, Ji, Peng Fei, He, Jin Na, Tian, Ming Li, Zhou, Feng Qun
• Format: Article
• Language: English
• Subjects: Chromaticity; Color temperature; Emission; Fittings; Luminescence; Nanocrystal silicon (nc-Si); Photoluminescence; Porous polysilicon; Rendering; Semiconductor; Silicon; White light; White light emission
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2016.06.098

Porous polysilicon is fabricated through hydrothermally etching polysilicon in the solution of hydrofluoric acid containing ferric nitrate, which is characterized by the pores with ~40nm and silicon nanocrystals (nc-Si) with an average size of ~4.1nm. Compared with the polysilicon, the reflectance of porous polysilicon is rather low. Using the Kubelka-Munk method, the band gap with ~3.35eV can be calculated. Under the excitation of 270nm, the white photoluminescence, which chromaticity coordinate, correlative color temperature and color rendering index are (0.36, 0.32), ~4185K and ~83.4, respectively, can be observed. Utilizing Gauss-Newton fitting method, white light can be decomposed into ultraviolet emission, blue emission and orange-red emission. Three peaks are attributed to the band gap emission of nc-Si, the luminescence centers formed in the silicon oxide layer and in the surface of nc-Si or in the silicon suboxidation layer encapsulating nc-Si, respectively. It is indicated that porous polysilicon might be a potential material in the white light emission field. [Display omitted] •Porous polysilicon is fabricated by hydrothermally etching polysilicon in the solution of HF and Fe(NO3)3.•The porous polysilicon is characterized by the pores and nc-Si with an average size of ~40nm and ~4.1nm, respectively.•White light emission can be obtained from two wider emission bands of porous polysilicon.