Interference lithography: a powerful tool for fabricating periodic structures

• Published in: Laser & photonics reviews 2010-06, Vol.4 (4), p.568-580
• Main Authors: Lu, C., Lipson, R.H.
• Format: Article
• Language: English
• Subjects: Beams (radiation); Data storage; Diffraction and scattering; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Holographic interferometry; other holographic techniques; Holography; Interference; interferometry; Lasers; Lithography; Optical materials; Optics; Periodic structures; phase shifting; Photolithography; Photonic bandgap materials; photoresists; Physics; Unit cell; Wave optics
• ISSN: 1863-8880; 1863-8899
• DOI: 10.1002/lpor.200810061

In this review the basic principles of interference lithography (IL) are described. IL is emerging as one of the most powerful yet relatively inexpensive methodologies for creating large‐area patterns with micron‐ to sub‐micron periodicities. N‐dimensional periodic structures (N ≤ 3) can be obtained by interfering (N + 1) non‐coplanar beams in a photoresist. The symmetry and shape of the “unit cell” can be conveniently controlled by varying the intensities, geometries, polarizations, and phases of the beams involved. IL done with shorter wavelength lasers and/or liquid immersion lithography can create features with sub‐50 nm dimensions. Such periodic structures are beginning to find wide use in photonic crystal science, optical telecommunications, data storage, and the integrated circuit industry. Newer innovations such as diffraction element assisted lithography or DEAL and phase‐controlled IL for making two‐dimensional structures are also discussed. Interference lithography (IL) is emerging as one of the most powerful yet relatively inexpensive methodologies for creating large‐area patterns with micron‐ to sub‐micron periodicities. $N$‐dimensional periodic structures ($N\leqslant 3$) can be obtained by interfering (${N + 1}$) non‐coplanar beams in a photoresist. IL done with shorter wavelength lasers and/or liquid immersion lithography can create features with sub‐50\,nm dimensions. Such periodic structures are beginning to find wide use in photonic crystal science, optical telecommunications, data storage, and the integrated circuit~industry.