Microelectromechanical and microfluidic systems for scanning probe lithography.

摘要

The emerging field of scanning probe lithography (SPL) has enabled scientific research down to an unprecedentedly small scale. Direct write SPL uses the scanning probe in an atomic force microscope (AFM) to generate chemical or biological patterns on a substrate. It offers a unique combination of performance advantages including nanoscale resolution, direct molecular transfer, pattern flexibility, and material versatility. It has been widely used for nanoscopic pattern generation and enabled many exciting nanotechnology applications ranging from molecular assembly to nanomaterial synthesis to nanoelectronic fabrication.; This work addresses two major challenges faced by traditional single-probe SPL technology---lithography throughput and probe coating technique. System-level improvements of SPL have been successfully achieved. First, micromachined, thermally actuated cantilever probe arrays are developed to improve the throughput and flexibility of SPL. Multiple distinct patterns have been generated simultaneously with sub-50-nm line width in dip pen nanolithography (DPN) mode. Then, development of scanning probe contact printing (SPCP) technology and multifunctional probe arrays has expanded the capability of conventional single-functional SPL and demonstrated an excellent example of a highly integrated scanning probe device for pattern generation in DPN and SPCP modes and pattern inspection in AFM and LFM modes. In addition, the development of integrated microfluidic inking chips for chemical ink handling and SPL probe treatment further enhances the power of arrayed scanning probes. The inking chip can potentially coat an array of SPL tips with different inks simultaneously for multi-ink lithography.