Methods and Apparatus for Nanolapping
A lapping system for lapping portions of a workpiece. The lapping system includes, a lap that is defined by a surface. Portions of the surface are a lapping surface. The lapping surface has a coating that enhances material removal from a workpiece in a lapping process. The lapping system further includes, a scanning probe microscope having a tip and a substrate. The scanning probe microscope controls lapping motion of the lap and workpiece.
1 . In an atomic force microscopy system, a method for identifying structural features of a scanning tip disposed at a free end of a cantilever comprising:
scanning the tip across a reference surface having a knife edge with predetermined dimensions and protruding from the reference surface at a non-orthogonal angle, the scanning including disposing the tip sufficiently proximate the reference surface so that interactions due to atomic forces between the tip and knife edge occur during scanning;
measuring the interactions to produce scan data;
producing information relating to the tip based on the scan data and on the known dimensions of the knife edge.
2 . The method of claim 1 wherein the information is an image of the tip.
3 . The method of claim 1 wherein the scanning is an atomic force microscopy (AFM) type of scan.
4 . The method of claim 1 wherein the scanning is a scanning tunneling microscopy (STM) type of scan.
5 . The method of claim 1 wherein the interactions are deflections of the free end of the workpiece as the tip is scanned across the reference surface.
6 . The method of claim 1 wherein the interactions are changes in a tunneling current flowing between the tip and the reference surface and the reference structures.
7 . The method of claim 1 further including subjecting the scanning tip to a lapping operation, the lapping operation being performed in a manner dependent on the information relating to the scanning tip.
8 . The method of claim 1 wherein the scanning tip is formed by lapping a shape into a portion of a workpiece with a lap, the shape constituting the scanning tip, a remaining portion of the workpiece being the cantilever, the lap having a lapping surface, the lapping surface being bounded a space defined by a 200 micrometers×200 micrometers×200 micrometers cube.
9 . The method of claim 8 wherein the lapping surface is non-planar.
10 . The method of claim 8 wherein the lapping surface comprises a plurality of surface segments.
11 . The method of claim 10 wherein the surface segments define a connected set.
12 . The method of claim 10 wherein the surface segments define a disconnected set.
13 . In an atomic force microscopy system, a method for identifying structural features of a scanning tip disposed at a free end of a cantilever comprising:
scanning the tip across a reference surface, the scanning tip sufficiently proximate the reference surface so that atomic interactions between the scanning tip and the reference surface deflect the cantilever, the reference surface having a knife edge protruding from the reference surface at a non-orthogonal angle, the reference surface and the knife edge having predetermined dimensions;
producing deflection signals indicative of deflections of the cantilever; and
producing information relating to the scanning tip based on the deflection signals and on the predetermined dimensions of the reference surface and the knife edge.
14 . The method of claim 13 wherein scanning includes moving the reference surface.
15 . The method of claim 13 wherein the reference surface includes a conical-shaped structure and/or a mushroom-shaped structure.
16 . The method of claim 13 further including subjecting the scanning tip to a lapping operation, the lapping operation being performed in a manner dependent on the information relating to the scanning tip.
17 . The method of claim 13 wherein the scanning tip is formed by lapping a shape into a portion of a workpiece with a lap, the shape constituting the scanning tip, a remaining portion of the workpiece being the cantilever, the lap having one or more lapping surfaces bounded by a space defined by a cube having dimensions of about 200 micrometers×200 micrometers×200 micrometers cube.