ملخص: In this work, we have fabricated a gas-sensing device based on hydrocarbon groups (CHx)/porous silicon (PS) structure. The porous layer was prepared electrochemically from p-type silicon. The porous samples were coated with hydrocarbons groups (CHx) deposited by plasma of methane under argon atmosphere.We found that heterojunction fabricated from thin CHx layer shows a good rectifying behaviour. This property, correlated with the porous silicon sensitivity to the gas environments, can be effectively used to realise heterojunction diodes whose current-voltage (I-V) characteristics are modified by the gas reactivity on the porous surface.Sensitivity of those devices, response time and impedance response to different gas exposure (ethylene, ethane and propane) have been investigated.FT-IR spectroscopy measurements in different gas environments show a reversible free-carrier detrapping in the IR region.

لغة: إنجليزية