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Large-area, oblique-incidence interferometric nanopatterning using a low-cost multilongitudinal-mode diode laser as the source and a spin-on-glass based diffraction-phase-mask grating beam splitter is demonstrated. The phase mask is engineered to have only two equal intensity orders (0th and −1st), dramatically simplifying the optical arrangement and decreasing the propagation distance between the beam splitter and the sample. The low-cost, high-power (150 mW) TEM00 405-nm diode laser operates with a large number of longitudinal modes, resulting in an impractical mask-to-sample-gap proximity requirement. A dual-grating-mask, achromatic interferometric scheme is introduced to extend this gap dimension to easily accessible scales. Uniform nanopatterns with a periodicity of 600 nm were fabricated over a 1 cm diameter area using this multimode diode laser. This technique is scalable and has the potential for large-area nanopatterning applications. 

Roll-to-roll and other high-speed printing manufacturing processes are increasingly being extended to micro- and nanoelectronics and photonics due to cost and throughput advantages as compared with traditional wafer-scale manufacturing. The extra degrees of freedom associated with a moving web require high speed, in-line metrology to control the manufacturing process. Many state-of-the-art metrology approaches have sub-10 nm resolution but cannot be implemented during real-time fabrication processes because of environmental constraints or contact/cross sectional requirements. Optical angular scatterometry is a non-contact metrology approach that can be implemented at high speed. We demonstrate a system that uses 45° off-axis parabolic mirrors and an 8kHz resonant scanner to vary the incident/reflected angle from ~17° to ~67°, suitable for nanoscale metrology at web speeds of up to 350 cm/s, well-beyond the speed of current manufacturing tools. Scatterometry is sensitive not only to gross defects (missing pattern sections) but also to variations in nanoscale pattern details, offering a pathway to feedback control of the manufacturing process.