AVS 53rd International Symposium
    Nanometer-scale Science and Technology Thursday Sessions
       Session NS-ThP

Paper NS-ThP16
Evaluation of Pattern Profiles Replicated by Nanoimprint Using AFM with Carbon Nanotube Tip

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: Nanoscale Science and Technology Poster Session
Presenter: J. Igaki, University of Hyogo, Japan
Authors: J. Igaki, University of Hyogo, Japan
K. Nakamatsu, University of Hyogo, Japan
K. Tone, Meisyo Co., Japan
T. Nishimura, SII NanoTechnology Inc., Japan
S. Matsui, University of Hyogo, Japan
Correspondent: Click to Email
Nanoimprint lithography (NIL) is a very useful technique to make nanostructure devices with low cost and high throughput. A various resist polymers such as PMMA are used as replicated materials for NIL. The observation of replicated pattern profile is usually carried out after cleaving a pattern by scanning electron microscopy (SEM). However, it is difficult to use this method to accurately position the cleavage for a cross-section of a specific pattern with nano dimensions. In contrast, atomic force microscope (AFM) evaluation enables non-destructive measurement without contamination or irradiation damage inevitable in SEM evaluation. Therefore, evaluation of replicated pattern using AFM has potential advantages. In this paper, we evaluated profiles of SiO2 mold (200 nm-thick SiO2 on Si) and PMMA replicated pattern on a Si substrate by AFM using carbon nanotube (CNT) as a probe. By using carbon nanotube as a probe, it enables obtaining a high resolution and high aspect pattern profile. First, a SiO2 pattern as a thermal NIL mold was fabricated by EB lithography and dry etching process. Next, PMMA patterns were replicated by thermal NIL process using SiO2 mold. SiO2 mold was pressed into PMMA layer at 120°C at a set press-pressure of 20 MPa. Finally, the shapes of SiO2 mold and PMMA replicated pattern were evaluated by AFM with CNT tip (L-trace, SII NanoTechnology Inc.). The pitch, line width, height and angle of gradient of the SiO2 mold were 600 nm, 221 nm, 198 nm and 82°, respectively. The pitch, line width, height and angle of gradient of the PMMA replicated pattern pressed at 120 °C were 604 nm, 226 nm, 194 nm and 82°, respectively. In this way, the shapes of SiO2 mold and the PMMA replicated pattern were well evaluated by AFM with CNT tip.