Defocused Ion Beam Etching of the Silicon Probes for High Resolution Atomic-force Microscopy

Atomic force microscopy is one of the most popular method of investigation of samples surface at nanoscale. The most common problem of atomic force microscopy (AFM) is the obtaining real geometrical parameters during the studing of nano scale objects. Actually obtained AFM image is a “convolution” of images of the cantilever tip and the investigated object. This effect, called “image convolution” limits the resolution of AFM. Thus one of the most important task for researchers is to minimize this effect by reducing tip size. Classic microelectronic batch process allows to create hundreds AFM cantilevers simultaneously with tip curvature radius from 10 nm and more. Individual process methods (for example focused ion beam) allows to reduce tip radius down to several nanometers but for one cantilever per time only. Authors developed technology to reduce probes curvature radius by using defocused ion beam. The method could be used for both individual and batch processes. Basic principles of technology and results of its implementation are showed in this paper.