Proposal for new atomic force microscopy (AFM) imaging for a high aspect structure (digital probing mode AFM)

A new imaging technique of digital probing method in atomic force microscop y (AFM) is proposed for the evaluation of high aspect structures. This meth od independently controls the probe in either xy- or Z-directional movement to remove torsion of the probe. The xy-movement only takes place when the probe is separated from the sample surface. During the approach of the prob e to the surface the xy-movement is stopped. This method allows to image th e dry-etched grooves faithfully. Compared with cross-section SEM observatio n with cracking of the sample, it is demonstrated that this method is advan tageous for the evaluation of the cross-section because of the short measur ement time and easy operation. (C) 2001 Elsevier Science BY All rights rese rved.