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Articles you may be interested inEffect of oxygen on growth and properties of diamond thin film deposited at low surface temperature Effect of high-voltage sheath electric field and ion-enhanced etching on growth of carbon nanofibers in highdensity plasma chemical-vapor deposition J. Appl. Phys. 98, 044313 (2005);

In this paper, the infrared optical properties of diamond films grown on silicon substrates by means of the microwave plasma chemical vapour deposition (MPCVD) method were first studied by infrared spectroscopic ellipsometry in the photo energy range of 0.1–0.4 eV. Using the effects of annealing treatment on the extinction coefficient k and refractive index n of diamond films, the infrared optical quality of the diamond film can be significantly improved by thermal annealing treatment in N2 atmosphere. After annealing the value of k was about 10−12–10−15. However, for the non-annealed diamond film, the value of k varied in a large range, about 10−3–10−14. After annealing the refractive index n of the diamond film increased and was close to that of a single crystal, Type IIa natural diamond. The graphite on the diamond surface can be removed to some extent after surface oxidizing treatment of the diamond film in a solution of H2O2 and H2SO4, which causes the obvious decrease of the leakage current of the CVD diamond detector. Based on these diamond films, diamond x-ray detectors with a response time of about 3 ns were fabricated. From the temperature behaviour and the time response of the CVD diamond detector to x-ray irradiation, we find that the various defects or impurities that exist in the film may be responsible for the long fall time.

A hydrogel film of chitosan/poly(acrylic acid) (CS/PAAc) copolymer with the property of pH sensitivity, was prepared by irradiating the chitosan film, which was then swelled by aqueous AAc solutions of different concentrations. The effects of the feed ratio of chitosan and AAc on the properties of the hydrogels, such as swelling ratio and pH‐sensitivity, were determined. Fourier transform infrared (FT‐IR) spectroscopy was applied in the attenuated total reflectance (ATR) mode for analyzing the structure change of the hydrogels after the treatment in buffer solutions of different pHs.

An n-ZnS/p-Si heterojunction was fabricated by using the rf magnetron sputtering method. The band gap of the ZnS film is about 3.63 eV. Current-voltage (𝐼-𝑉 ) characteristics of the ZnS/Si heterojunction are examined and the results show the distinct rectifying characteristics with a turn-on voltage of about 1.8 V. The UV (330 nm) and visible (450 nm) photoresponse properties of the heterojunction are also investigated, which demonstrates the potential of such an n-ZnS/p-Si heterojunction for detecting both UV and visible light.