NUV/VIS sensitive multicolor thin film detector based on a-SiC:H/a-Si:H/¦Ìc-SiGeC:H alloys with an in-situ structured transparent conductive oxide front contact without etching

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• 作者：A. Bablich ; M. Boehm
• 关键词：Amorphous silicon ; Photonic device ; Reflectance measurement ; Color detection ; Photovoltaics ; Imaging ; Chemical analysis
• 刊名：Thin Solid Films
• 出版年：2012
• 出版时间：1 October, 2012
• 年：2012
• 卷：520
• 期：24
• 页码：7189-7194
• 全文大小：1551 K

文摘

An innovative family of hydrogenated amorphous silicon (a-Si:H) multicolor p-i-n photo sensors, sensitive in the VIS and the near UV spectrum, is presented. Typical values of the quantum efficiency at 350 nm and 580 nm are 5.4 % and 54.7 % , respectively, with ? 0.4 V and ? 12 V bias. Electro-optical studies were performed to explore the effect of combining linearly graded a-SiGe:H/¦Ìc-SiGeC:H layers with linearly graded a©\SiC:H-layers. The devices presented additionally contain a buried a-Si:H region. Low-reflective aluminum doped zinc oxide (ZnO:Al) back contacts improve the spectral color separation. ¦Ì¦Ó-products and absorption coefficients of graded absorbers were determined. Discrete absorbers were substituted by a linear graded a-SiC:H absorption zone in the top structure, an interior a-Si:H region and a graded a-SiGe:H/a-SiC:H alloy combination. In this paper we demonstrate a reduction of interference fringes and operation at low bias voltages, combined with a highly precise adjustment of the spectral sensitivity, even in the near UV-spectrum. The device dynamic range exceeds 50 dB at 1000 lx white-light illumination. As the deposited upper layers adopt the roughness of ¦Ìc-SiGeC:H clusters in the rear absorber, we present an in-situ structured front contact without etching ZnO:Al.