Method of calibrating a plurality of metrology devices

A method comprising:

• (a) positioning, at a first location, n, with respect to a first plurality of targets on a wafer, an array comprising a second plurality of MEMS-based atomic force microscopes (AFMs), each AFM having a cantilever/tip that is actuatable to move in a vertical direction, and wherein:
• (i) the targets have a first pitch, wherein the first pitch defines the separation between the targets,
• (ii) the array of AFMs are fabricated in monolithic silicon, the array having a pitch that is identical to the first pitch,
• (iii) there are more targets in the first plurality than AFMs in the array;
• (b) scanning, with each AFM, at a wide field-of-view (FOV), a number of targets equal to a number of AFMs in the array, wherein the scanning determines a location of respective ones of the targets by respective ones of the AFMs;
• (c) scanning, with each AFM, at a zoom FOV, the first number of targets, thereby obtaining a measurement of the targets;
• (d) advancing the array from location n to location n+1, and repeating (b) and (c);
• and
• (e) repeating (b)-(d) until each AFM in the array has obtained the measurement of each target in the first plurality thereof,
• wherein, since the pitch of the array precisely matches the pitch of the targets, each target will be within the zoom FOV of a respective AFM without having to laterally reposition the tip thereof, which, in the absence of an ability to laterally move the tip of each AFM, otherwise requires disengaging and re-positioning the array of AFMs.