Nano structured sensing surface: Significance in sensor fabrication

Trend of using miniaturized sensors in various fields is rapidly growing. Related sensing surface topology can crucially affect the performance of a sensor by affecting various sensing characteristics. Effect of probe dimensions on sensing performance is discussed in context to various kind of sensors employed in different applications. Modification of conventional techniques and development of modern approaches have helped researchers to fabricate at sub micro and Nano level. Contrary, manufacturing of such high performance surface with desired topology remains challenge in certain cases. Conventional material removing method like dry and wet etching and material deposition methods like physical vapor deposition (PVD), chemical vapor deposition (CVD) and atomic layer deposition (ALD) are elaborated in a context to modern trend and challenges it presents for the fabrication of micro and nano structured sensing surfaces. Modern and inexpensive approach of laser ablation for fabrication of porous and fibrous thin-film, mainly for silicon, is discussed along with the effect of various control parameter on porous silicon surface topology including theoretical limitation for minimum diameter of nanofibers for sensing applications.