Dear Yogendra, a former colleague of mine used porous Si thin layer, porous poly-Si, or porous Si-C for humidity sensor, and also for other gas sensor. Perhaps you can try it. Please have a look at: http://scholar.google.com/scholar?hl=en&lr=&cluster=1649166982137917822 regards, Dedy Yogendra Yadav_04322601 wrote: > Dear All, > I am working on microcantilvere based humdity sensor. i have made the > device i.e microcantilver of nitride and oxide. for sensing film i > want to use polyimide but i have not been able to get for long time. > it is because the polyimide now a days has been made to have less > water absorbing capacity. the earlier series which i want to use is > not availabale anywhere. > > I request plz anyone can help me in finding option for polyimide which > i can use as sensing film on my cantilever to detect the moisture.