scispace - formally typeset
Search or ask a question
Author

G. Lang

Bio: G. Lang is an academic researcher. The author has contributed to research in topics: Cladding (fiber optics) & Wetting. The author has an hindex of 2, co-authored 2 publications receiving 48 citations.

Papers
More filters
Journal ArticleDOI
TL;DR: In this article, a flexible approach to produce optical interconnects on 6096 $ast,$6096 mm large-area panels is demonstrated, where waveguide routing design allows optical waveguides on different 1016$ast,$ 1016 mm tiles to be interconnected and four different waveguide connecting geometries in the border region between tiles are fabricated and tested.
Abstract: A flexible approach to producing optical interconnects on 6096 $ast ,$ 6096 mm large-area panels is demonstrated Stepwise projection patterning from 1016 $ast ,$ 1016 mm masks has generated optical waveguide patterns over the whole panel using large-area projection lithography equipment The waveguide routing design allows optical waveguides on different 1016 $ast ,$ 1016 mm tiles to be interconnected Four different waveguide connecting geometries in the border region between tiles have been fabricated and tested Multimode waveguides from inorganic-organic hybrid polymers (ORMOCER) (cross section: $le hbox 50~muhbox mast hbox 10~muhbox m$ ) with refractive index step between core and cladding $Delta n=hbox 001$ were produced The index step was adjusted by mixing two diffrent ORMOCER systems The materials show good adhesion to numerous substrates, such as glass and silicon Application concepts such as flexible manufacturing of optoelectrical hybrid backplanes with two-dimensional interconnect, a three-dimensional optical interconnect with optical vias, and a hybrid backplane with the optical interconnect in a strip-format on a separate plane right above the electrical plane are proposed Promising new technologies are presented along with preliminary demonstrativ viability

45 citations

Journal ArticleDOI
TL;DR: In this paper, a mixture of ORMOCER materials and tuning agents was used as a cladding material for large-area panel (LAP) processing to prevent dewetting effects of the core layer from cladding layer.
Abstract: Upon processing waveguide structures by using the ORMOCER materials ORMOCORE as core material, and a mixture of ORMOCORE and ORMOCER-III (refractive index tuning agent) as cladding material, dewetting effects of the core layer from the cladding layer were observed. A similar phenomenon was observed for a mixture of ORMOCORE and ORMOCLAD which was used as comparative refractive index tuning material. In order to use these material combinations for large-area panel (LAP) processing, a pretreatment or activation of surfaces is necessary but hard to realize. However, the addition of small amounts of ORMOCER-III or ORMOCLAD, respectively, to the core layer material, prevented the dewetting phenomenon. The objective of this, however, is to minimize the content of refractive index tuning agent in the core layer by retaining a good wetting behavior during multilayer processing. Wet film stability tests and contact angle measurements of these ORMOCER systems in various compositions on another ORMOCER surface of a specific cladding material composition were performed on a hotplate. Furthermore, contact angles of droplets formed by deionized water, formamide, and di-iodomethane on cured surfaces of these ORMOCER systems in a wide range of compositions were characterized, and surface tensions were calculated. By adding 0.1 wt% of ORMOCER-III or 5 wt% ORMOCLAD, respectively, to the pure ORMOCORE solution, the dewetting phenomenon was eliminated, while simultaneously the refractive index was affected only to a minor degree and no changes in the optical loss could be detected. It was shown that by adding ORMOCER-III or ORMOCLAD to pure ORMOCORE, the surface tension of the compound system was reduced. In comparison to silanization or gasplasma treatment to overcome dewetting effects in microelectronics multilayer processing, the investigated mixing method eliminates process steps and thus costs, and opens new process routes for LAP processing

3 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: The description and discussion of the major applications of hybrid inorganic-organic (or biologic) materials are the major topic of this critical review.
Abstract: Today cross-cutting approaches, where molecular engineering and clever processing are synergistically coupled, allow the chemist to tailor complex hybrid systems of various shapes with perfect mastery at different size scales, composition, functionality, and morphology. Hybrid materials with organic–inorganic or bio–inorganic character represent not only a new field of basic research but also, via their remarkable new properties and multifunctional nature, hybrids offer prospects for many new applications in extremely diverse fields. The description and discussion of the major applications of hybrid inorganic–organic (or biologic) materials are the major topic of this critical review. Indeed, today the very large set of accessible hybrid materials span a wide spectrum of properties which yield the emergence of innovative industrial applications in various domains such as optics, micro-electronics, transportation, health, energy, housing, and the environment among others (526 references).

1,159 citations

Journal ArticleDOI
TL;DR: In this paper, a simple fabrication method for multimode polymer optical waveguides with graded-index (GI) circular cores is introduced for use in optical printed circuit boards (O-PCBs).
Abstract: A simple fabrication method for multimode polymer optical waveguides with graded-index (GI) circular cores is introduced for use in optical printed circuit boards (O-PCBs). The new method, named “Mosquito method,” utilizes a microdispenser to dispense a viscous monomer directly onto the substrates. By optimizing the dispensing conditions, 12-channel parallel waveguides with circular GI-cores (core diameter of 40 μm) are successfully fabricated using the Mosquito method. The advantages of GI-core waveguides for O-PCB applications are discussed by comparing the optical characteristics of the fabricated waveguides with those of conventional step-index (SI) square-core polymer waveguides, and even with those of silica-based GI multimode fibers (MMFs), as an ideal case. To the best of our knowledge, this is the first comparison of SI- and GI-core multimode polymer waveguides that are composed of the same polymer materials and that have similar core and pitch sizes. We experimentally demonstrate that the GI circular-core polymer waveguides fabricated by the Mosquito method have sufficiently low propagation loss (0.033 dB/cm at 850 nm), low connection loss with GI-MMFs, and low interchannel crosstalk. We observe approximately -50 dB of interchannel crosstalk in the 250-μm pitch GI-core waveguide fabricated, which is almost 10 dB lower than in the SI counterpart. Furthermore, sufficiently low crosstalk is maintained in a half-pitch GI-core waveguide fabricated by the Mosquito method.

108 citations

Journal ArticleDOI
TL;DR: Channel waveguides are fabricated by direct lithographic patterning, photoresist-templated etching, or soft-lithographic approaches, but these techniques are limited either to in-plane confi gurations or require repeated developing or etching steps to produce multiple layers of waveguide.
Abstract: N Integrated optical systems require waveguides that can route light along defi ned pathways with minimal losses and negligible crosstalk. [ 1–3 ] In addition to signal transmission, optical waveguides play an important role in the area of sensing. For example, evanescent fi eld sensors are applied to the detection of analytes in the body, [ 4 ] atmosphere, [ 5 ] and liquid solutions. [ 6 ] Polymeric and hybrid materials are of increasing interest for these applications due to their low temperature processing. [ 7 ] To date, channel waveguides have been fabricated by direct lithographic patterning, [ 8 , 9 ] photoresist-templated etching, [ 10 ] or soft-lithographic approaches. [ 11 , 12 ] However, these techniques are limited either to in-plane confi gurations or require repeated developing or etching steps to produce multiple layers of waveguides. Those processing steps often have a deleterious effect on waveguide performance, leading to rough edges and, hence, higher optical loss. [ 8 , 11 , 13 ]

74 citations

Journal ArticleDOI
TL;DR: A scalable and tolerant optical interfacing method based on flip-chip bonding is developed for silicon photonics packaging and does not exhibit any temperature dependence up to the highest measurement point of 70°C.
Abstract: A scalable and tolerant optical interfacing method based on flip-chip bonding is developed for silicon photonics packaging. Bidirectional optical couplers between multiple silicon-on-insulator waveguides and single-mode polymer waveguides are designed and fabricated. Successful operation is verified experimentally in the 1530-1570 nm spectral window. At the wavelength of 1570 nm, the coupling loss is as low as 0.8 dB for both polarization states and the planar misalignment loss is less than 0.6 dB for TE and 0.3 dB for TM polarization in a lateral silicon-polymer waveguide offset range of ± 2 µm. The coupling loss does not exhibit any temperature dependence up to the highest measurement point of 70°C.

60 citations

Journal ArticleDOI
TL;DR: The reevaluation of the optical power budget for realistic high-speed optical polymer-waveguide links on backplanes showed that signal amplification is necessary to boost the signal, which resulted in an additional literature review on advances in optical amplifiers based on silicon bench technology available.
Abstract: In this paper, recent literature on the discussion on high-speed backplanes with optical, electrical, and mixed solutions, as well as on polymer-waveguide systems suitable for implementation on printed circuit boards (PCBs), is reviewed from the point of view of their optical losses. The reevaluation of the optical power budget for realistic high-speed optical polymer-waveguide links on backplanes showed that signal amplification is necessary to boost the signal, which resulted in an additional literature review on advances in optical amplifiers based on silicon bench technology available. Finally, a concept study of an active optical waveguide amplifier device, based on planar optical waveguide amplifiers and semiconductor optical amplifiers, was performed. The amplification device can be flip-chip mounted on the backplane to compensate for optical losses due to signal routing, which increases the overall degree of freedom in waveguide routing on high-density interconnects for backplanes. The hybrid concept design guarantees compatibility with the processes of the PCB industry.

50 citations