Study On Performance Of Alcohol Gas Sensor Based On Semiconductor Nano Thin Films

With the improvement of people's living standards,automobile industry has got rapid development,but that comes with the hazard is obvious,increasing the probability of occurrence of traffic accidents,according to the WHO survey shows that 50 to 60 percent of traffic accidents are caused by drunk driving,a serious threat to our personal safety,so alcohol testing has aroused wide concern.Nanostructured gas sensors with specific surface area,high surface activity,surface gas channel,easy integration and many other advantages,so much favored by researchers,nanometer titanium dioxide film not only inherits the advantages,but also has high sensitivity,low working temperature,quick response,easy preparation,and other unique advantages.Therefore,this paper choose the titanium dioxide nano films as the sensitive material of alcohol gas sensor.In order to further improve the sensing characteristics of the device,this paper introduces the design of laminated composite structure prepared SnO₂ and TiO₂ laminated nanometer thin films,improve the sensitivity of the device;in addition,the substrate is processed,using the method of double tank electrochemical corrosion prepared the porous silicon substrate,in order to improve the specific surface area and improve the sensing properties.The specific research contents are as follows:?1?The Ti electrode was grown on the substrate by electron beam evaporation,and then the TiO₂ nano thin film was deposited by the multi function magnetron sputtering equipment.And to study the effects of growth process of various conditions on the film properties and device sensing performance,get the best technological conditions for oxygen argon ratio2.5:57.5,power 120 W,pressure 0.8pa,the substrate to target distance of 7cm,the substrate temperature 450?.?2?Using magnetron sputtering to prepare TiO₂ and SnO₂ thin film laminated structure,since both have the similar lattice structure,under the condition of high temperature can replace each other particles inside the ion,so the surface activity enhanced,the charge transfer increases,thus device sensitivity has been significantly improved.?3?Etching the p-type silicon by double tank electrochemical corrosion method,corrosion solution to volume ratio 2:1 N,N-dimethyl formamide and hydrofluoric acid mixed solution,when the current is 64 m A,of preparing out of the aperture is about 400 nm porous silicon,nanometer TiO₂ thin films were deposited by,prepared sensor,the sensitivity is increased 2 times,response / recovery time within 10 seconds.