Fabrication of optical mosaic gratings: a self-referencing alignment method.

We propose and demonstrate a self-referencing alignment technique to conveniently enlarge fabricated grating area. The latent image gratings are used as the reference objects to align (adjust and lock) the attitude and position of the substrate relative to the exposure beams between and during consecutive exposures. The adjustment system and the fringe-locking system are combined into the exposure system, eliminating the drift errors between them and making the whole system low-cost and compact. For the fabricated 1 × 4 mosaics of 50 × (30 + 30 + 30 + 30) mm(2) area and 1 × 2 mosaics of 90 × (80 + 80) mm(2) area, the typical peak-valley -1st-order wavefront errors measured by a 100-mm-diameter interferometer are not more than 0.06 λ and 0.09 λ, respectively.

[1]  Steven R. J. Brueck,et al.  Interferometric lithography of sub‐micrometer sparse hole arrays for field‐emission display applications , 1996 .

[2]  Eung-Sug Lee,et al.  The fabrication of a flexible mold for high resolution soft ultraviolet nanoimprint lithography , 2008, Nanotechnology.

[3]  C. Black.  Nanowire arrays build themselves , 2007, Nature Nanotechnology.

[4]  T. Kamiya,et al.  Development of latent images due to transient free carrier electrons by femtosecond laser pulses and its application to grating shape trimming , 2007 .

[5]  H. Sugimura,et al.  Force microscopy imaging of photopatterned organosilane monolayers: application to probe alignment in AFM patterning following photolithography , 1998 .

[6]  Ray M. Sharples,et al.  The optical design of the Southern African Large Telescope high resolution spectrograph: SALT HRS , 2008, Astronomical Telescopes + Instrumentation.

[7]  Lei Shi,et al.  Fabrication of optical mosaic gratings by consecutive holographic exposures employing a latent-fringe based alignment technique , 2010, SPIE/COS Photonics Asia.

[8]  Nicholas J. Phillips,et al.  Use of real-time latent images to write long holographic diffraction gratings in photoresist , 1997, Electronic Imaging.

[9]  D B Tanner,et al.  Phase effects in the diffraction of light: beyond the grating equation. , 2005, Physical review letters.

[10]  D. Clery.  Power. Laser fusion energy poised to ignite. , 2010, Science.

[11]  Jan Scrimgeour,et al.  Three‐Dimensional Optical Lithography for Photonic Microstructures , 2006 .

[12]  Lijiang Zeng,et al.  Fabrication of optical mosaic gratings with phase and attitude adjustments employing latent fringes and a red-wavelength dual-beam interferometer. , 2009, Optics express.