Deconvolution of local surface response from topography in nanometer profilometry with a dual-scan method

In profilometric measurements, by scanning the sample twice with a fixed ve rtical offset, one can separate the signal that comes from surface heteroge neity from the topographic signal. Using differential confocal microscopy, a newly developed open-loop nanometer profilometric technique, we demonstra ted this dual-scan method on composite samples and obtained 10-nm depth res olution. This technique can also be applied to other profilometric techniqu es such as atomic force microscopy and scanning tunneling microscopy. (C) 1 999 Optical Society of America.