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As the design rule becomes smaller, meeting the precision metrology demands from the industries is becoming more complex. Traditional tools, such as stylus profiler, optical microscope, and CD-SEM are proving to have insufficient resolution. Atomic Force Microscopes (AFM) have gained attention as a new candidate for nanoscale metrology tool. Most conventional AFM systems used a piezoelectric tube actuator, which has significant background curvature and crosstalk between the x-y-z axes, making them unsuitable for metrology applications. Furthermore, the character of the industrial metrological target is getting more delicate and complex and it becomes more difficult to produce an accurate measurement. In order to overcome these limits, we introduced the XE-series AFM, which has a z-scanner separated from the x-y scanner, but also developed other means to resolve these metrological problems. With this new AFM and methods, we were able to successfully measure the dimensions of Pole-Tip Recession (PTR) in Magneto-Resistance (MR) head, which had been difficult to be measured by conventional AFM in the past. At this time, we present the way to make an accurate measurement on an angled sample and it is gathering much of optical industry (especially in LCD panel production)'s attention. There are several factors to make this measurement difficult with AFM. The half cone angle of the tip, drift of the system, the flattening of the sample tilting, un-orthogonality between XY and Z scanner and nonlinearity of the XY and Z detector are the elements for the difficulties. We emphasized the importance of the separated flexure type X-Y scanner and other means in order to measure such angled samples accurately. |