| AVS 61st International Symposium & Exhibition | |
| Scanning Probe Microscopy Focus Topic | Thursday Sessions |
| Session SP+AS+EM+NS+SS-ThP |
| Session: | Scanning Probe Microscopy Poster Session |
| Presenter: | James Su, Instrument Technology Research Center, National Applied Research Laboratories, Taiwan, Republic of China |
| Authors: | J.Y. Su, Instrument Technology Research Center, National Applied Research Laboratories, Taiwan, Republic of China N.N. Chu, Instrument Technology Research Center, National Applied Research Laboratories, Taiwan, Republic of China M.H. Shiao, Instrument Technology Research Center, National Applied Research Laboratories, Taiwan, Republic of China C.N. Hsiao, Instrument Technology Research Center, National Applied Research Laboratories, Taiwan, Republic of China |
| Correspondent: | Click to Email |
Atomic force microscopy (AFM) has an important role in dimensional metrology especially in the nanoscale. The morphology image processed by the AFM is the interaction between the tip and the sample surface. The result of the interaction may cause broadening of peaks and shrinking of valleys in the scanning process caused by tip effects. It would be impossible to differentiate the portion due to the tip and the portion due to the sample surface without determining the tip geometry which is a key role in AFM-image quality. As a case study, AFM measurements of nanowires (NW), carbon nanotubes (CNT) and nano-honeycombs fabricated by nanosphere lithography (NSL) technology are examined. Line width measurement results may expand up to 39.5% by adopting a conventional pyramid-shaped probe and 17.5% by using a conical-shaped one as the dimensions of the scanned features approaches to the order of magnitude of the tip apex. The uncertainty of measurement would expand if tip wear occurs during image scan. Calculation for surface reconstruction has been developed to extract the part related to the tip from the SPM image. The SPM used for these measurements is equipped with a highly accurate scanning system, which employs closed-loop capacitive feedback control to ensure outstanding linearity and position accuracy. To identify the geometry of the tip, a silicon tip characterization grating was imaged between the measurements. Deconvolution process were carried out for topography image corrections, and the results were further compared with the ones measured from the scanning electron microscope (SEM). This process is essential to derive accurate measurement results in the nanoscale region.