Influence of discrete drop locations on film thickness uniformity in UV- nanoimprint lithography

• Published in: Microelectronic engineering Vol. 164; pp. 139 - 144
• Main Authors: Singhal, Shrawan, Sreenivasan, S.V.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2016
• Subjects: Correlation; Film thickness; Inkjetting; Jet and Flash Imprint Lithography; Lithography; Lubrication theory; Mathematical models; Nanoimprint lithography; Placement; Residual layer thickness uniformity; Thickness; Tolerances; Variability; Lubrication theory; Nanoimprint lithography; Residual layer thickness uniformity; Inkjetting; Jet and Flash Imprint Lithography
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2016.07.014

Multi-nozzle inkjetting is the material deposition approach for a variant of UV-nanoimprint lithography called Jet-and-Flash Imprint Lithography (J-FIL). J-FIL has several advantages with respect to addressing pattern density variations in the template as well as achieving low material waste when compared with spin-coating. In this work, the influence of discrete drop placement in J-FIL on residual layer thickness uniformity has been investigated with the help of a novel nonlinear lubrication theory model, which takes into account the compliant nature of the template in the presence of a moving contact line. This work is directed at thin residual layers (sub-20nm), where a correlation exists between minimum drop resolution, inkjet nozzle pitch and residual layer thickness uniformity. Numerical simulations reveal that the non-uniformity resulting from discrete drop placement can exceed desired process tolerances when low film thicknesses are desired with relatively larger drop volumes. The results have been verified experimentally to reveal the same trend. This work can be useful in determining the correlation of inkjet drop resolution with inkjet nozzle pitch to meet process tolerances in the J-FIL process. [Display omitted] •Inkjet drop pitch affects residual layer thickness uniformity in J-FIL.•Thin films can suffer from undesirable non-uniformity with large drop volumes.•Inkjet nozzle pitch can be optimized based on results from this work.