Pattern-integrated interference lithography instrumentation

Abstract

Multi-beam interference (MBI) provides the ability to form a wide range of sub-micron periodic optical-intensity distributions with applications to a variety of areas, including photonic crystals (PCs), nanoelectronics, biomedical structures, optical trapping, metamaterials, and numerous subwavelength structures. Recently, pattern-integrated interference lithography (PIIL) was presented as a new lithographic method that integrates superposed pattern imaging with interference lithography in a single-exposure step. In the present work, the basic design and systematic implementation of a pattern-integrated interference exposure system (PIIES) is presented to realize PIIL by incorporating a projection imaging capability in a novel three-beam interference configuration. A fundamental optimization methodology is presented to model the system and predict MBI-patterning performance. To demonstrate the PIIL method, a prototype PIIES experimental configuration is presented, including detailed alignment techniques and experimental procedures. Examples of well-defined PC structures, fabricated with a PIIES prototype, are presented to demonstrate the potential of PIIL for fabricating dense integrated optical circuits, as well as numerous other subwavelength structures.

Modeling of multiple-optical-axis pattern-integrated interference lithography systems

“…With the demand for increasingly smaller components and devices permeating human existence, Pattern-Integrated Interference Lithography (PIIL), was first developed in the Georgia Tech Optics Laboratory in 2012 as a technique to produce, in a rapid, singlestep, interference patterns with integrated functional elements in one, two, and three dimensions [1][2][3][4][5][6][7][8][9][10]. This technique was developed for use in the specific application areas of mirco-and nano-electronics [1,[11][12][13][14], photonic crystals [1,[15][16][17][18][19][20][21][22][23][24], and biomedical structures [1,20,[25][26][27][28][29][30] based upon other interference lithography (IL) techniques that had been used for these applications.…”

“…This technique was developed for use in the specific application areas of mirco-and nano-electronics [1,[11][12][13][14], photonic crystals [1,[15][16][17][18][19][20][21][22][23][24], and biomedical structures [1,20,[25][26][27][28][29][30] based upon other interference lithography (IL) techniques that had been used for these applications. While a prototype system in a single-optical-axis (SOA) configuration has been experimentally demonstrated as a proof-of-concept, PIIL systems are still in a research and development stage [1][2][3][4][5][6][7][8][9][10].…”

“…The primary objective of the research presented in this thesis is to establish a methodology for characterizing, simulating, and optimizing an MOA PIIES using a xiv combination of ray tracing and Fourier analysis applied to the single-element, nonoptimal lenses previously used in an SOA PIIES implementation [1,4,5]. No attempt has been made to start with more appropriate components.…”

“…Interference Lithography (PIIL), first developed in the Georgia Tech Optics Laboratory in 2012, provides an attractive option for a variety of applications as it can produce in a single-step, interference patterns with integrated functional elements in one, two, and three dimensions [1][2][3][4][5][6][7][8][9][10]. While a prototype system in a single-optical-axis (SOA) configuration has been experimentally demonstrated as a proof-of-concept, PIIL systems are still in a research and development stage [1][2][3][4][5][6][7][8][9][10].…”

Pattern-integrated interference lithography: Vector modeling and 1D, 2D, and 3D device structures

“…[25][26][27] This novel microfabrication approach couples interference lithography and imaging lithography simultaneously. As a result, PIIL potentially enables the single-exposure fabrication of 1D, 2D, or 3D periodic microstructures with embedded functional elements.…”