Nanohole Structuring for Improved Performance of Hydrogenated Amorphous Silicon Photovoltaics
详细信息 查看全文
- 作者：Eric Johlin ; Ahmed Al-Obeidi ; Gizem Nogay ; Michael Stuckelberger ; Tonio Buonassisi ; Jeffrey C. Grossman
- 刊名：ACS Applied Materials & Interfaces
- 出版年：2016
- 出版时间：June 22, 2016
- 年：2016
- 卷：8
- 期：24
- 页码：15169-15176
- 全文大小：454K
- 年卷期：0
- ISSN：1944-8252
文摘
While low hole mobilities limit the current collection and efficiency of hydrogenated amorphous silicon (a-Si:H) photovoltaic devices, attempts to improve mobility of the material directly have stagnated. Herein, we explore a method of utilizing nanostructuring of a-Si:H devices to allow for improved hole collection in thick absorber layers. This is achieved by etching an array of 150 nm diameter holes into intrinsic a-Si:H and then coating the structured material with p-type a-Si:H and a conformal zinc oxide transparent conducting layer. The inclusion of these nanoholes yields relative power conversion efficiency (PCE) increases of ∼45%, from 7.2 to 10.4% PCE for small area devices. Comparisons of optical properties, time-of-flight mobility measurements, and internal quantum efficiency spectra indicate this efficiency is indeed likely occurring from an improved collection pathway provided by the nanostructuring of the devices. Finally, we estimate that through modest optimizations of the design and fabrication, PCEs of beyond 13% should be obtainable for similar devices.