Method and system for determining key dimension of low-dimensional materials by optical scattering

A method for determining a key dimension of low-dimensional materials by optical scattering, comprising:

• controlling a light source to be obliquely incident onto a low-dimensional material to be observed and a substrate at a set angle, wherein the set angle is able to enable a light receiving device located above or below the low-dimensional material to be observed to only receive light scattered by the low-dimensional material to be observed;
• converting the received scattered light into an optical image;
• obtaining a brightness value of each pixel in the optical image, and establishing a correspondence relationship between a position and brightness;
• using a difference value between brightness of the low-dimensional material to be observed and brightness of the substrate as a contrast, wherein the brightness of the low-dimensional material to be observed is a maximum brightness value of a low-dimensional material region;
• the brightness of the substrate is an average brightness value of a region beyond the low-dimensional material to be observed;
• and
• calculating a contrast based on the correspondence relationship between the position and the brightness, and determining the key dimension of the low-dimensional material to be observed by using a pre-calibrated correspondence relationship between the contrast and the key dimension of the low-dimensional material to be observed.