Blind evaluation of AFM tip shape by using optical glass surface with irregular nanostructures as a tip characteriser

Abstract

Atomic-force microscopy (AFM) is a type of scanning probe microscopy. It possesses nano-scale resolution which is >1000 times better than the optical diffraction limit. An image of AFM is the result of interaction between the tip and the sample. The AFM image is not accurate and distorted due to the finite size of the probe tip. To correct the AFM image and acquire accurate sample morphology information, it needs to evaluate the tip shape and status. The shape of the probe tip is calculated to determine the quality of the probe. The optical glass surface fabricated by free abrasive polishing (traditional mechanical polishing) technique is used as a new tip characteriser to calibrate the AFM probe tip. Meanwhile, an improved blind reconstruction algorithm is adopted to calculate the AFM tip shape and size. In the help of matrices, the blind reconstruction algorithm is elaborated clearly. The optical glass surface with irregular nanostructures ensures that the morphology of probe tip can be determined accurately. Without independent knowledge of the sample morphology, the three-dimensional morphology of the AFM tip can be obtained.

Positioning Technology of Tiny Electronic Components Based on Microscope and Computer Vision

“…Experimental results show that the gray system theory is effective, has the function of an adjustable edge detection algorithm, and can more accurately detect the edges of useful information. Has a certain anti-noise ability, can effectively improve the positioning accuracy of BGA chips [1]. Cao inputs the coordinate of the feature point image into the calibrated system to obtain the actual coordinate of the feature point.…”