Scanning microscope comprising force-sensing means and position-sensitive photodetector

A near-field scanning optical microscope which comprises an optical fiber having first and second ends and a tapered terminal portion including the first end, means for positioning the first end adjacent a surface of a sample, and means for displacing the first end relative to the sample in a raster pattern lying in a plane, to be referred to as the "scanning plane," substantially parallel to a portion of the surface such that the surface portion is scanned, the microscope further comprising:

• a) means for oscillating the probe tip relative to the surface, the direction of the oscillations lying substantially within the scanning plane;
• b) a position-sensitive photodetector capable of producing an output signal;
• c) means for optically imaging the probe tip onto the position-sensitive photodetector such that at least some changes in the oscillation of the probe will cause changes in the output signal;
• d) means for deriving a feedback signal from the output signal;
• and
• e) means for controlling the distance between the first end and the sample surface such that the feedback signal is maintained substantially constant while the first end is being displaced in a raster pattern.

A method for manufacturing an article, comprising the steps of:

• a) providing a multiplicity of semiconductor bodies, each semiconductor body having a surface to be patterned;
• b) setting at least one process parameter;
• c) processing at least a first semiconductor body according to the process parameter such that a pattern is formed on the surface of the semiconductor body, the pattern having a characteristic dimension;
• d) measuring the characteristic dimension in the first semiconductor body;
• e) comparing the characteristic dimension to a predetermined range of values;
• f) if the characteristic dimension lies outside the predetermined range of values, changing the process parameter to bring the characteristic dimension within the predetermined range of values;
• g) after (f), processing at least a second semiconductor body according to the process parameter;
• and
• h) performing, on at least the second semiconductor body, at least one additional step toward completion of the article, characterized in that
• the measuring step comprises situating, adjacent a portion of the surface, a probe having a tip;
• displacing the probe tip relative to the surface such that a scan pattern is described in a plane, to be referred to as the "scanning plane", which lies substantially parallel to the surface portion;
• oscillating the probe tip, relative to the surface, such that the oscillations lie substantially within the scanning plane;
• optically imaging the probe tip onto a position-sensitive photodetector which produces an output signal;
• and processing the output signal such that changes in the oscillation of the probe tip are detected.