The hydrogenated amorphous carbon-silicon alloys [a-SixC1−x(n):Hy] and [a-Six(n):Hy] layers were investigated in order to prove the feasibility to widen the optical band gap in emitters of the heterojunction solar cells. The alloys were fabricated by decomposition of silane (SiH4), phosphine (PH3), methane (CH4), and hydrogen (H2), using a plasma enhanced chemical vapor deposition. Particularly, we focused on the incorporation of hydrogen and carbon within the resulting [a-SixC1−x(n):Hy] and [a-Six(n):Hy] films, which later form the emitter. The corresponding local vibrational modes of Si−Hx, C−H, and the corresponding network have been analyzed by μ-Raman spectroscopy. The addition of carbon degrades the photoelectronic properties in the emitter layer. This deterioration can be minimized by H dilution. The resulting optical band gap EG as well as the thickness of the emitter were determined by spectroscopic ellipsometry. It was confirmed that the band gap EG can be tailored by using an appropriate gas mixture during the decomposition. Furthermore, we analyzed the I−V characteristics of the prepared heterojunction solar cells. A trade-off between the electrical defects density and the optical losses induced an improvement of the I−V characteristics with increasing carbon and hydrogen concentration in the feedstock during the deposition.
A 16.5 megapixel camera lens for a mobile phone is designed. The lens consists of 3 plastic aspheric lenses, one glass spheric lens and an infrared glass filter. CMOS OV16850 with a pixel size of 1.12 micrometers from Omni Vision is used as an image sensor. The lens has an effective focal length of 4.483 mm, a F-number of 2.50, a field-of-view (FOV) of 76.2 degree, and a total length of 5.873 mm. The maximum distortion of the lens is less than 2.0%. The minimum value of all field relative illumination is over 39.8%.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.