2021
Xia, Chun; Kuebler, Stephen M; Martinez, Noel P; Martinez, Manuel; Rumpf, Raymond C; Touma, Jimmy
Wide-band self-collimation in a low-refractive-index hexagonal lattice Journal Article
In: Optics Letters, vol. 46, no. 9, pp. 2228-2231, 2021.
Abstract | Links | BibTeX | Tags: hexagonal, multiphoton lithography, photonic crystals, self-collimation
@article{nokey,
title = {Wide-band self-collimation in a low-refractive-index hexagonal lattice},
author = {Chun Xia and Stephen M Kuebler and Noel P Martinez and Manuel Martinez and Raymond C Rumpf and Jimmy Touma
},
url = {https://www.osapublishing.org/ol/abstract.cfm?uri=ol-46-9-2228},
doi = {10.1364/OL.421860},
year = {2021},
date = {2021-05-01},
urldate = {2021-05-01},
journal = {Optics Letters},
volume = {46},
number = {9},
pages = {2228-2231},
abstract = {Wide-angle, broadband self-collimation (SC) is demonstrated in a hexagonal photonic crystal (PhC) fabricated in a low-refractive-index photopolymer by multiphoton lithography. The PhC can be described as a hexagonal array of cylindrical air holes in a block of dielectric material having a low-refractive index. Optical characterization shows that the device strongly self-collimates light at near-infrared wavelengths that span 1360 to 1610 nm. SC forces light to flow along the extrusion direction of the lattice without diffractive spreading, even when light couples into the device at high oblique angles. Numerical simulations corroborate the experimental findings.},
keywords = {hexagonal, multiphoton lithography, photonic crystals, self-collimation},
pubstate = {published},
tppubtype = {article}
}
Wide-angle, broadband self-collimation (SC) is demonstrated in a hexagonal photonic crystal (PhC) fabricated in a low-refractive-index photopolymer by multiphoton lithography. The PhC can be described as a hexagonal array of cylindrical air holes in a block of dielectric material having a low-refractive index. Optical characterization shows that the device strongly self-collimates light at near-infrared wavelengths that span 1360 to 1610 nm. SC forces light to flow along the extrusion direction of the lattice without diffractive spreading, even when light couples into the device at high oblique angles. Numerical simulations corroborate the experimental findings.
2019
Sharma, Rashi; Kuebler, Stephen M; Grabill, Christopher N; Digaum, Jennefir L; Kosan, Nicholas R; Cockerham, Alexander R; Martinez, Noel; Rumpf, Raymond C
Fabrication of Functional Nanophotonic Devices via Multiphoton Polymerization Presentation
27.02.2019, ISSN: 1947-5918.
Abstract | Links | BibTeX | Tags: multi-photon lithography (MPL), photonic crystals, polymer
@misc{RN143,
title = {Fabrication of Functional Nanophotonic Devices via Multiphoton Polymerization},
author = {Rashi Sharma and Stephen M Kuebler and Christopher N Grabill and Jennefir L Digaum and Nicholas R Kosan and Alexander R Cockerham and Noel Martinez and Raymond C Rumpf},
url = {https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10915/1091502/Fabrication-of-functional-nanophotonic-devices-by-multiphoton-lithography/10.1117/12.2508675.short?SSO=1},
doi = {https://doi.org/10.1117/12.2508675},
issn = {1947-5918},
year = {2019},
date = {2019-02-27},
urldate = {2019-02-27},
journal = {Polymer-Based Additive Manufacturing: Recent Developments},
pages = {151-171},
abstract = {Multi-photon lithography (MPL) is a laser-based method for 3D printing nanoscale devices. Since its introduction in the late 1990's, researchers across many disciplines have made exciting contributions toward its development that include extending the range of material systems available for MPL, improving the achievable resolution, and using it to create functional devices for optics, MEMS, microfluidics, sensing, and bio-engineering. MPL has been used to create conventional micro-optics, like waveguides and micro-lenses. It has also been used to fabricate devices onto novel platforms, such as the tips of optical fibers, which greatly extends the functionality of conventional optics and the range of applications they may serve. MPL is unique among existing fabrication methods in its potential for creating truly 3D structures having arbitrary shape and complexity. This is particularly well illustrated in recent reports of using MPL to create spatially-variant photonic crystals (SVPCs). SVPCs unlock new physical mechanisms to control light, particularly using self-collimation to flow beams through exceptionally sharp bends, which cannot be achieved with waveguides and other technologies based on refraction. MPL and SVPCs open new routes to integrated photonics and opto-electronic circuits.},
keywords = {multi-photon lithography (MPL), photonic crystals, polymer},
pubstate = {published},
tppubtype = {presentation}
}
Multi-photon lithography (MPL) is a laser-based method for 3D printing nanoscale devices. Since its introduction in the late 1990's, researchers across many disciplines have made exciting contributions toward its development that include extending the range of material systems available for MPL, improving the achievable resolution, and using it to create functional devices for optics, MEMS, microfluidics, sensing, and bio-engineering. MPL has been used to create conventional micro-optics, like waveguides and micro-lenses. It has also been used to fabricate devices onto novel platforms, such as the tips of optical fibers, which greatly extends the functionality of conventional optics and the range of applications they may serve. MPL is unique among existing fabrication methods in its potential for creating truly 3D structures having arbitrary shape and complexity. This is particularly well illustrated in recent reports of using MPL to create spatially-variant photonic crystals (SVPCs). SVPCs unlock new physical mechanisms to control light, particularly using self-collimation to flow beams through exceptionally sharp bends, which cannot be achieved with waveguides and other technologies based on refraction. MPL and SVPCs open new routes to integrated photonics and opto-electronic circuits.
2015
Rumpf, Raymond C; Pazos, Javier J; Digaum, Jennefir L; Kuebler, Stephen M
Spatially variant periodic structures in electromagnetics Journal Article
In: Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, vol. 373, no. 2049, pp. 20140359, 2015, ISSN: 1364-503X.
Abstract | Links | BibTeX | Tags: fuctionally graded, metamaterials, metasurfaces, optics, photonic crystals, physiological optics, spatially variant, transformation optics
@article{RN102,
title = {Spatially variant periodic structures in electromagnetics},
author = {Raymond C Rumpf and Javier J Pazos and Jennefir L Digaum and Stephen M Kuebler},
url = {https://royalsocietypublishing.org/doi/full/10.1098/rsta.2014.0359},
doi = {https://doi.org/10.1098/rsta.2014.0359},
issn = {1364-503X},
year = {2015},
date = {2015-08-28},
journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences},
volume = {373},
number = {2049},
pages = {20140359},
abstract = {Spatial transforms are a popular technique for designing periodic structures that are macroscopically inhomogeneous. The structures are often required to be anisotropic, provide a magnetic response, and to have extreme values for the constitutive parameters in Maxwell's equations. Metamaterials and photonic crystals are capable of providing these, although sometimes only approximately. The problem still remains about how to generate the geometry of the final lattice when it is functionally graded, or spatially varied. This paper describes a simple numerical technique to spatially vary any periodic structure while minimizing deformations to the unit cells that would weaken or destroy the electromagnetic properties. New developments in this algorithm are disclosed that increase efficiency, improve the quality of the lattices and provide the ability to design aplanatic metasurfaces. The ability to spatially vary a lattice in this manner enables new design paradigms that are not possible using spatial transforms, three of which are discussed here. First, spatially variant self-collimating photonic crystals are shown to flow unguided waves around very tight bends using ordinary materials with low refractive index. Second, multi-mode waveguides in spatially variant band gap materials are shown to guide waves around bends without mixing power between the modes. Third, spatially variant anisotropic materials are shown to sculpt the near-field around electric components. This can be used to improve electromagnetic compatibility between components in close proximity.},
keywords = {fuctionally graded, metamaterials, metasurfaces, optics, photonic crystals, physiological optics, spatially variant, transformation optics},
pubstate = {published},
tppubtype = {article}
}
Spatial transforms are a popular technique for designing periodic structures that are macroscopically inhomogeneous. The structures are often required to be anisotropic, provide a magnetic response, and to have extreme values for the constitutive parameters in Maxwell's equations. Metamaterials and photonic crystals are capable of providing these, although sometimes only approximately. The problem still remains about how to generate the geometry of the final lattice when it is functionally graded, or spatially varied. This paper describes a simple numerical technique to spatially vary any periodic structure while minimizing deformations to the unit cells that would weaken or destroy the electromagnetic properties. New developments in this algorithm are disclosed that increase efficiency, improve the quality of the lattices and provide the ability to design aplanatic metasurfaces. The ability to spatially vary a lattice in this manner enables new design paradigms that are not possible using spatial transforms, three of which are discussed here. First, spatially variant self-collimating photonic crystals are shown to flow unguided waves around very tight bends using ordinary materials with low refractive index. Second, multi-mode waveguides in spatially variant band gap materials are shown to guide waves around bends without mixing power between the modes. Third, spatially variant anisotropic materials are shown to sculpt the near-field around electric components. This can be used to improve electromagnetic compatibility between components in close proximity.
2014
Pazos, Javier Jair
Digitally manufactured spatially variant photonic crystals PhD Thesis
2014, (960871768 by Javier Jair Pazos. illustrations (mostly color) ; 4 3/4 inches. Vita. Includes bibliographical references. Also available online. CD-ROM requires Adobe Acrobat Reader and CD-ROM drive. University of Texas at El Paso. Doctoral dissertation.).
Links | BibTeX | Tags: dielectric devices, electromagnetic testing, metamaterials, particle size determination, photonic crystals
@phdthesis{RN172,
title = {Digitally manufactured spatially variant photonic crystals},
author = {Javier Jair Pazos},
url = {http://0-search.proquest.com.lib.utep.edu/pqdtglobal/docview/1703031279/32D98817B27C49FBPQ/1?accountid=7121},
year = {2014},
date = {2014-12-04},
urldate = {2014-12-04},
note = {960871768
by Javier Jair Pazos.
illustrations (mostly color) ; 4 3/4 inches.
Vita.
Includes bibliographical references.
Also available online.
CD-ROM requires Adobe Acrobat Reader and CD-ROM drive.
University of Texas at El Paso. Doctoral dissertation.},
keywords = {dielectric devices, electromagnetic testing, metamaterials, particle size determination, photonic crystals},
pubstate = {published},
tppubtype = {phdthesis}
}
2013
Rumpf, Raymond C; Pazos, Javier J
Optimization of planar self-collimating photonic crystals Journal Article
In: JOSA A, vol. 30, no. 7, pp. 1297-1304, 2013, ISSN: 1520-8532.
Abstract | Links | BibTeX | Tags: figure of merit, photonic crystals, self-collimation, silicon photonics, spatially variant photonic crystals
@article{RN73,
title = {Optimization of planar self-collimating photonic crystals},
author = {Raymond C Rumpf and Javier J Pazos},
url = {https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-30-7-1297#articleBody},
doi = {https://doi.org/10.1364/JOSAA.30.001297},
issn = {1520-8532},
year = {2013},
date = {2013-05-01},
journal = {JOSA A},
volume = {30},
number = {7},
pages = {1297-1304},
abstract = {Self-collimation in photonic crystals has received a lot of attention in the literature, partly due to recent interest in silicon photonics, yet no performance metrics have been proposed. This paper proposes a figure of merit (FOM) for self-collimation and outlines a methodical approach for calculating it. Performance metrics include bandwidth, angular acceptance, strength, and an overall FOM. Two key contributions of this work include the performance metrics and identifying that the optimum frequency for self-collimation is not at the inflection point. The FOM is used to optimize a planar photonic crystal composed of a square array of cylinders. Conclusions are drawn about how the refractive indices and fill fraction of the lattice impact each of the performance metrics. The optimization is demonstrated by simulating two spatially variant self-collimating photonic crystals, where one has a high FOM and the other has a low FOM. This work gives optical designers tremendous insight into how to design and optimize robust self-collimating photonic crystals, which promises many applications in silicon photonics and integrated optics.},
keywords = {figure of merit, photonic crystals, self-collimation, silicon photonics, spatially variant photonic crystals},
pubstate = {published},
tppubtype = {article}
}
Self-collimation in photonic crystals has received a lot of attention in the literature, partly due to recent interest in silicon photonics, yet no performance metrics have been proposed. This paper proposes a figure of merit (FOM) for self-collimation and outlines a methodical approach for calculating it. Performance metrics include bandwidth, angular acceptance, strength, and an overall FOM. Two key contributions of this work include the performance metrics and identifying that the optimum frequency for self-collimation is not at the inflection point. The FOM is used to optimize a planar photonic crystal composed of a square array of cylinders. Conclusions are drawn about how the refractive indices and fill fraction of the lattice impact each of the performance metrics. The optimization is demonstrated by simulating two spatially variant self-collimating photonic crystals, where one has a high FOM and the other has a low FOM. This work gives optical designers tremendous insight into how to design and optimize robust self-collimating photonic crystals, which promises many applications in silicon photonics and integrated optics.
2012
Kuebler, Stephen M; Williams, Henry E; Freppon, Daniel J; Rumpf, Raymond C; Melino, Marco A
Creation of three-dimensional micro-photonic structures on the end-face of optical fibers Journal Article
In: Journal of Laser Micro Nanoengineering, vol. 7, no. 3, pp. 293, 2012.
Abstract | Links | BibTeX | Tags: Applied, laser materials processing, micro-optics, microstructure fabrication, Multidisciplinary Optics Physics, nanophotonics, photonic crystals, SU-8
@article{RN60,
title = {Creation of three-dimensional micro-photonic structures on the end-face of optical fibers},
author = {Stephen M Kuebler and Henry E Williams and Daniel J Freppon and Raymond C Rumpf and Marco A Melino},
url = {https://stars.library.ucf.edu/facultybib2010/2890/},
year = {2012},
date = {2012-01-01},
urldate = {2012-01-01},
journal = {Journal of Laser Micro Nanoengineering},
volume = {7},
number = {3},
pages = {293},
abstract = {A process is reported that enables fabrication of truly three-dimensional micro-photonic structures directly onto the end face of an optical fiber by multi-photon direct laser writing in the cross-linkable epoxide SU-8. Solvent-free SU-8 resin is first obtained by heating in vacuo to remove volatiles. The resulting resin solids are then melt-reflowed around an optical fiber in a mold integrated into a sample mount. The resin is allowed to cool and solidify around the optical fiber, so the entire sample mount can be affixed to an optical system for direct laser writing. Using this approach a wide range of refractive and diffractive micro-optical structures can be integrated onto optical fibers that would be difficult, if not impossible, to create by other existing methods. Optical characterization of lens-tipped fibers shows that the approach can be used control the propagation of beams exiting from functionalized fibers, and the performance is reproducible across repeated fabrication of the same device. This work illustrates a new path to fiber-based integrated photonic devices.},
keywords = {Applied, laser materials processing, micro-optics, microstructure fabrication, Multidisciplinary Optics Physics, nanophotonics, photonic crystals, SU-8},
pubstate = {published},
tppubtype = {article}
}
A process is reported that enables fabrication of truly three-dimensional micro-photonic structures directly onto the end face of an optical fiber by multi-photon direct laser writing in the cross-linkable epoxide SU-8. Solvent-free SU-8 resin is first obtained by heating in vacuo to remove volatiles. The resulting resin solids are then melt-reflowed around an optical fiber in a mold integrated into a sample mount. The resin is allowed to cool and solidify around the optical fiber, so the entire sample mount can be affixed to an optical system for direct laser writing. Using this approach a wide range of refractive and diffractive micro-optical structures can be integrated onto optical fibers that would be difficult, if not impossible, to create by other existing methods. Optical characterization of lens-tipped fibers shows that the approach can be used control the propagation of beams exiting from functionalized fibers, and the performance is reproducible across repeated fabrication of the same device. This work illustrates a new path to fiber-based integrated photonic devices.
2009
Srinivasan, Pradeep; Yilmaz, Yigit Ozan; Rumpf, Raymond C; Johnson, Eric G
Micro-optical spatial and spectral elements Journal Article
In: Optical Engineering, vol. 48, no. 11, pp. 110501, 2009, ISSN: 0091-3286.
Abstract | Links | BibTeX | Tags: image filtering, optical filters, photonic crystals, spatial filters
@article{RN57,
title = {Micro-optical spatial and spectral elements},
author = {Pradeep Srinivasan and Yigit Ozan Yilmaz and Raymond C Rumpf and Eric G Johnson},
url = {https://www.spiedigitallibrary.org/journals/optical-engineering/volume-48/issue-11/110501/Micro-optical-spatial-and-spectral-elements/10.1117/1.3258651.full?SSO=1},
doi = {https://doi.org/10.1117/1.3258651},
issn = {0091-3286},
year = {2009},
date = {2009-11-01},
journal = {Optical Engineering},
volume = {48},
number = {11},
pages = {110501},
abstract = {Interference filters have a defect layer incorporated within a photonic crystal structure and generate a narrow transmission notch within a wide stop band. In this paper, we propose and demonstrate wavelength-tunable spatial filters by introducing diffractive optical elements in the defect layer. The spectral transmission through the device was a function of the local defect layer thickness under broadband illumination. For each wavelength, the spatial transmission followed the contours of equal defect layer optical thickness. The devices were implemented by depositing a one-dimensional photonic crystal with a centrally integrated defect layer on a silicon substrate using plasma-enhanced chemical vapor deposition. The defect layer was lithographically patterned with charge 2, 8-level vortex structures. The spectral transmission peak and linewidth was characterized by separately illuminating each zone of diffractive element using a tunable laser source and compared with model simulations. The spatial transmission through the device was imaged onto a CCD camera. Triangular wedge-shaped zones with wavelength-dependent orientations were observed. These novel devices with spectrally tunable spatial transmission have potential applications in pupil filtering, hyperspectral imaging, and engineered illumination systems.},
keywords = {image filtering, optical filters, photonic crystals, spatial filters},
pubstate = {published},
tppubtype = {article}
}
Interference filters have a defect layer incorporated within a photonic crystal structure and generate a narrow transmission notch within a wide stop band. In this paper, we propose and demonstrate wavelength-tunable spatial filters by introducing diffractive optical elements in the defect layer. The spectral transmission through the device was a function of the local defect layer thickness under broadband illumination. For each wavelength, the spatial transmission followed the contours of equal defect layer optical thickness. The devices were implemented by depositing a one-dimensional photonic crystal with a centrally integrated defect layer on a silicon substrate using plasma-enhanced chemical vapor deposition. The defect layer was lithographically patterned with charge 2, 8-level vortex structures. The spectral transmission peak and linewidth was characterized by separately illuminating each zone of diffractive element using a tunable laser source and compared with model simulations. The spatial transmission through the device was imaged onto a CCD camera. Triangular wedge-shaped zones with wavelength-dependent orientations were observed. These novel devices with spectrally tunable spatial transmission have potential applications in pupil filtering, hyperspectral imaging, and engineered illumination systems.
2006
Rumpf, Raymond C
Design and optimization of nano-optical elements by coupling fabrication to optical behavior PhD Thesis
2006.
Abstract | Links | BibTeX | Tags: guided mode resonance (GMR), nanophotonics, photonic crystals
@phdthesis{RN25,
title = {Design and optimization of nano-optical elements by coupling fabrication to optical behavior},
author = {Raymond C Rumpf},
url = {https://stars.library.ucf.edu/cgi/viewcontent.cgi?article=2080&context=etd},
year = {2006},
date = {2006-04-13},
abstract = {Photonic crystals and nanophotonics have received a great deal of attention over the last decade, largely due to improved numerical modeling and advances in fabrication technologies.
To this day, fabrication and optical behavior remain decoupled during the design phase and numerous assumptions are made about "perfect" geometry. As research moves from theory to real devices, predicting device behavior based on realistic geometry becomes critical. In this dissertation, a set of numerical tools was developed to model micro and nano fabrication processes. They were combined with equally capable tools to model optical performance of the simulated structures. Using these tools, it was predicted and demonstrated that 3D nanostructures may be formed on a standard mask aligner. A space-variant photonic crystal filter was designed and optimized based on a simple fabrication method of etching holes through hetero-structured substrates. It was found that hole taper limited their optical performance and a method was developed to compensate. A method was developed to tune the spectral response of guided-mode resonance filters at the time of fabrication using models of etching and deposition.
Autocloning was modeled and shown that it could be used to form extremely high aspect ratio
structures to improve performance of form-birefringent devices. Finally, the numerical tools
were applied to metallic photonic crystal devices.},
keywords = {guided mode resonance (GMR), nanophotonics, photonic crystals},
pubstate = {published},
tppubtype = {phdthesis}
}
Photonic crystals and nanophotonics have received a great deal of attention over the last decade, largely due to improved numerical modeling and advances in fabrication technologies.
To this day, fabrication and optical behavior remain decoupled during the design phase and numerous assumptions are made about "perfect" geometry. As research moves from theory to real devices, predicting device behavior based on realistic geometry becomes critical. In this dissertation, a set of numerical tools was developed to model micro and nano fabrication processes. They were combined with equally capable tools to model optical performance of the simulated structures. Using these tools, it was predicted and demonstrated that 3D nanostructures may be formed on a standard mask aligner. A space-variant photonic crystal filter was designed and optimized based on a simple fabrication method of etching holes through hetero-structured substrates. It was found that hole taper limited their optical performance and a method was developed to compensate. A method was developed to tune the spectral response of guided-mode resonance filters at the time of fabrication using models of etching and deposition.
Autocloning was modeled and shown that it could be used to form extremely high aspect ratio
structures to improve performance of form-birefringent devices. Finally, the numerical tools
were applied to metallic photonic crystal devices.
To this day, fabrication and optical behavior remain decoupled during the design phase and numerous assumptions are made about "perfect" geometry. As research moves from theory to real devices, predicting device behavior based on realistic geometry becomes critical. In this dissertation, a set of numerical tools was developed to model micro and nano fabrication processes. They were combined with equally capable tools to model optical performance of the simulated structures. Using these tools, it was predicted and demonstrated that 3D nanostructures may be formed on a standard mask aligner. A space-variant photonic crystal filter was designed and optimized based on a simple fabrication method of etching holes through hetero-structured substrates. It was found that hole taper limited their optical performance and a method was developed to compensate. A method was developed to tune the spectral response of guided-mode resonance filters at the time of fabrication using models of etching and deposition.
Autocloning was modeled and shown that it could be used to form extremely high aspect ratio
structures to improve performance of form-birefringent devices. Finally, the numerical tools
were applied to metallic photonic crystal devices.
Srinivasan, Pradeep; Rumpf, Raymond C; Johnson, Eric G
Fabrication of 3D photonic crystals by two-step dry etching of layered media Proceedings
International Society for Optics and Photonics, vol. 6110, 2006.
Abstract | Links | BibTeX | Tags: etching, photonic crystals
@proceedings{RN49,
title = {Fabrication of 3D photonic crystals by two-step dry etching of layered media},
author = {Pradeep Srinivasan and Raymond C Rumpf and Eric G Johnson},
url = {https://www.spiedigitallibrary.org/conference-proceedings-of-spie/6110/1/Fabrication-of-3D-photonic-crystals-by-two-step-dry-etching/10.1117/12.646461.short?SSO=1},
doi = {https://doi.org/10.1117/12.646461},
year = {2006},
date = {2006-01-23},
booktitle = {Micromachining Technology for Micro-Optics and Nano-Optics IV},
volume = {6110},
pages = {611006},
publisher = {International Society for Optics and Photonics},
abstract = {Photonic crystals have received growing interest over the past decade on account of their excellent functionality to guiding and manipulating electromagnetic radiation and their diverse applications. Our approach to fabricate crystals is by a two step etching process in a semiconductor hetero-structure of gallium arsenide (GaAs) and aluminum gallium arsenide (AlGaAs) grown using molecular beam epitaxy (MBE). An array of holes was dry etched in Cl 2 /Ar inductively coupled plasma. Etching selectivity between the mask and the substrate was 10:1.2 By using SF 6 Â in addition to the boron-tri-chloride (BCl 3 ) chemistry, the GaAs is etched selectively over the AlGaAs with selectivities over 5:1. Thus a robust two-step etching process has been developed based entirely on dry etching},
keywords = {etching, photonic crystals},
pubstate = {published},
tppubtype = {proceedings}
}
Photonic crystals have received growing interest over the past decade on account of their excellent functionality to guiding and manipulating electromagnetic radiation and their diverse applications. Our approach to fabricate crystals is by a two step etching process in a semiconductor hetero-structure of gallium arsenide (GaAs) and aluminum gallium arsenide (AlGaAs) grown using molecular beam epitaxy (MBE). An array of holes was dry etched in Cl 2 /Ar inductively coupled plasma. Etching selectivity between the mask and the substrate was 10:1.2 By using SF 6 Â in addition to the boron-tri-chloride (BCl 3 ) chemistry, the GaAs is etched selectively over the AlGaAs with selectivities over 5:1. Thus a robust two-step etching process has been developed based entirely on dry etching
2005
Rumpf, Raymond C; Johnson, Eric G
Modeling the formation of photonic crystals by holographic lithography Proceedings
International Society for Optics and Photonics, vol. 5720, 2005.
Abstract | Links | BibTeX | Tags: holographic lithography, photolithography, photonic crystals
@proceedings{RN43,
title = {Modeling the formation of photonic crystals by holographic lithography},
author = {Raymond C Rumpf and Eric G Johnson},
url = {https://www.spiedigitallibrary.org/conference-proceedings-of-spie/5720/1/Modeling-the-formation-of-photonic-crystals-by-holographic-lithography/10.1117/12.601186.short},
doi = {https://doi.org/10.1117/12.601186},
year = {2005},
date = {2005-01-22},
booktitle = {Micromachining Technology for Micro-Optics and Nano-Optics III},
volume = {5720},
pages = {18-26},
publisher = {International Society for Optics and Photonics},
abstract = {An approach is introduced to accurately explore methods of fabricating photonic crystals formed by holographic lithography. Analytical background is given for synthesizing the exposure beam configuration to form the desired lattice. This is combined with a comprehensive model that can predict lattice distortions due to physics of the photolithography process. Simulations are compared to experimental results and to results obtained by conventional intensity threshold methods.},
keywords = {holographic lithography, photolithography, photonic crystals},
pubstate = {published},
tppubtype = {proceedings}
}
An approach is introduced to accurately explore methods of fabricating photonic crystals formed by holographic lithography. Analytical background is given for synthesizing the exposure beam configuration to form the desired lattice. This is combined with a comprehensive model that can predict lattice distortions due to physics of the photolithography process. Simulations are compared to experimental results and to results obtained by conventional intensity threshold methods.
2004
Rumpf, Raymond C; Johnson, Eric G
Fully three-dimensional modeling of the fabrication and behavior of photonic crystals formed by holographic lithography Journal Article
In: JOSA A, vol. 21, no. 9, pp. 1703-1713, 2004, ISSN: 1520-8532.
Abstract | Links | BibTeX | Tags: face-centered-cubic photonic crystal, holographic lithography, optical absorption, photonic crystals
@article{RN23,
title = {Fully three-dimensional modeling of the fabrication and behavior of photonic crystals formed by holographic lithography},
author = {Raymond C Rumpf and Eric G Johnson},
url = {https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-21-9-1703},
doi = {https://doi.org/10.1364/JOSAA.21.001703},
issn = {1520-8532},
year = {2004},
date = {2004-05-01},
urldate = {2004-05-01},
journal = {JOSA A},
volume = {21},
number = {9},
pages = {1703-1713},
abstract = {A comprehensive and fully three-dimensional model of holographic lithography is used to predict more rigorously the geometry and transmission spectra of photonic crystals formed in Epon ®  SU-8 photoresist. It is the first effort known to the authors to incorporate physics of exposure, postexposure baking, and developing into three-dimensional models of photonic crystals. Optical absorption, reflections, standing waves, refraction, beam coherence, acid diffusion, resist shrinkage, and developing effects combine to distort lattices from their ideal geometry. These are completely neglected by intensity-threshold methods used throughout the literature to predict lattices. Numerical simulations compare remarkably well with experimental results for a face-centered-cube (FCC) photonic crystal. Absorption is shown to produce chirped lattices with broadened bandgaps. Reflections are shown to significantly alter lattice geometry and reduce image contrast. Through simulation, a diamond lattice is formed by multiple exposures, and a hybrid trigonal–FCC lattice is formed that exhibits properties of both component lattices.},
keywords = {face-centered-cubic photonic crystal, holographic lithography, optical absorption, photonic crystals},
pubstate = {published},
tppubtype = {article}
}
A comprehensive and fully three-dimensional model of holographic lithography is used to predict more rigorously the geometry and transmission spectra of photonic crystals formed in Epon ®  SU-8 photoresist. It is the first effort known to the authors to incorporate physics of exposure, postexposure baking, and developing into three-dimensional models of photonic crystals. Optical absorption, reflections, standing waves, refraction, beam coherence, acid diffusion, resist shrinkage, and developing effects combine to distort lattices from their ideal geometry. These are completely neglected by intensity-threshold methods used throughout the literature to predict lattices. Numerical simulations compare remarkably well with experimental results for a face-centered-cube (FCC) photonic crystal. Absorption is shown to produce chirped lattices with broadened bandgaps. Reflections are shown to significantly alter lattice geometry and reduce image contrast. Through simulation, a diamond lattice is formed by multiple exposures, and a hybrid trigonal–FCC lattice is formed that exhibits properties of both component lattices.