The B-tip will provide similar advantages for AFM as the ball probe does for CMM metrology. It has a form that can enter the narrowest trenches or holes and probe both sidewalls. The extent of overhang or the degree of re-entrance that it can probe, however, is not as large as for the J-tip. The J-tip, on the other hand, is designed to probe one sidewall only, and cannot image the opposite one. It does, however, have a more effective geometry for imaging the bottom corner region—since the end is oriented at nearly normal to the local surface at the corner transition region—and in lithometrology applications, this region is of considerable interest. The J-tip provides a small vertical edge height (VEH), equal to the end radius of the CNT. This might be an advantage for some applications if the radius can be measured a priori. The J-tip may also be useful for experimental line-width measurement procedures in which two images taken in opposite sample orientation are stitched together to form a composite image.28