Scanning force microscopes (SFMs) have become valuable instruments for inspection of surfaces on a submicron scale in the semiconductor industry. Their ability to track the position of a surface with an accuracy of the order of 1 nm opens the door to applications in micro- or nanometrology. Standard SFMs, using a conical shaped tip, are being applied to measurements of the height or depth of shallow features, such as via holes or small lines and trenches, that cannot readily be characterized by scanning electron microscopy or optical techniques. Recent technical developments of the SFM have provided new capabilities for accurate measurement of the line and trench width using a flared tip and an improved scanning and tracking method for the tip. Laboratory tests as well as industrial tests have revealed that repeatability in measuring critical dimensions approaches 1 nm. If careful attention is given to issues of calibration, particularly for the motion of the tip and for dimensioning of the tip itself, SFM techniques may attain accuracies that approach their measurement precision.