Recherche

Afficher tous les résultats pour

Accueil

Personne

Toralf Scharf

Cette personne n’est plus à l’EPFL

À propos
Confidentialité
Mentions légales

Graph Chatbot

Publications associées (107)

Mask-aligner lithography using a continuous-wave diode laser frequency-quadrupled to 193 nm

Toralf Scharf, Raoul Kirner, Andreas Vetter

2018

Improving the resolution in mask-aligner lithography

Wilfried Noell, Toralf Scharf, Raoul Kirner, Andreas Vetter

For the back-end microfabrication in integrated circuits and for the manufacturing of light emitting diodes, proximity mask-aligner lithography is still the tool of choice, due to its simplicity and low costs. However, the downscaling of functional element ...

IEEE2018

Design rules for customizable optical materials based on nanocomposites

Toralf Scharf, Friedrich Daniel Werdehausen

Nanocomposites with tailored optical properties can provide a new degree of freedom for optical design. However, despite their potential these materials remain unused in bulk optical applications. Here we investigate the conditions under which they can be ...

OPTICAL SOC AMER2018

Unified rule based correction for corners in proximity lithography mask using high resolution features

Hans Peter Herzig, Toralf Scharf, Krishnaparvathy Puthankovilakam

Printing industry and printing techniques are increasing its market value by new methodologies. The resolution and accuracy of the pattern transfer is always a challenge for the industry, especially for the proximity printing industries which use mask alig ...

Elsevier2017

Scaling effect and its impact on wavelength-scale microlenses

Hans Peter Herzig, Myun Sik Kim, Toralf Scharf

We revisit the scaling laws in micro-optical systems to highlight new phenomena arising beyond a conventional optical regime, especially when the size of the system approaches to the operational wavelength. Our goal is to visualize the impact of the scalin ...

Spie-Int Soc Optical Engineering2017

Light fields behind microstructures: study of the Babinet-principle in the Fresnel regime

Hans Peter Herzig, Myun Sik Kim, Toralf Scharf, Krishnaparvathy Puthankovilakam

The Babinet’s principle is a general theorem that holds for electromagnetic waves and is often applied to diffraction of light. Diffraction pattern of a body and that of the complement body are compared and the sum of both radiation patterns must be the sa ...

Spie-Int Soc Optical Engineering2017

Coherence management in lithography printing systems

Hans Peter Herzig, Toralf Scharf, Johana Bernasconi

In proximity lithography, interference and diffraction effects arise when printing small features because of the proximity gap. Different techniques are used in order to control and take advantage of theses effects. In this paper, the focus is set on the M ...

Spie-Int Soc Optical Engineering2016

Refraction limit of miniaturized optical systems: a ball-lens example

Hans Peter Herzig, Wilfried Noell, Roland Andreas Bitterli, Myun Sik Kim, Toralf Scharf

We study experimentally and theoretically the electromagnetic field in amplitude and phase behind ball-lenses across a wide range of diameters, ranging from a millimeter scale down to a micrometer. Based on the observation, we study the transition between ...

Optical Society of America2016

Intensity and phase fields behind phase-shifting masks studied with high-resolution interference microscopy

Hans Peter Herzig, Myun Sik Kim, Toralf Scharf, Ali Naqavi, Krishnaparvathy Puthankovilakam

We try to find out the details of how light fields behind the structures of photomasks develop in order to determine the best conditions and designs for proximity printing. The parameters that we use approach real situations like structure printing at prox ...

SPIE-Intl Soc Optical Eng2016

Array imaging system for lithography

Wilfried Noell, Toralf Scharf, Raoul Kirner

We present an integrated array imaging system based on a stack of microlens arrays. The microlens arrays are manufactured by melting resist and reactive ion etching (RIE) technology on 8'' wafers (fused silica) and mounted by wafer-level packaging (WLP)(1) ...

Spie-Int Soc Optical Engineering2016

Unconventional Optical Responses of Wavelength-scale Microlenses: beyond Refraction Limit

Hans Peter Herzig, Myun Sik Kim, Toralf Scharf

Miniaturized optical systems show often unconventional responses compare to larger systems of the same design. We investigate such new phenomena using microlenses, and demonstrate characteristics beyond the refraction limit of the micro-optical systems. ...

Ieee2016

Precision glass molding of high-resolution diffractive optical elements

Hans Peter Herzig, Toralf Scharf, Karin Prater

The demand of high resolution diffractive optical elements (DOE) is growing. Smaller critical dimensions allow higher deflection angles and can fulfill more demanding requirements, which can only be met by using electron-beam lithography. Replication techn ...

Spie-Int Soc Optical Engineering2016

Lightfields behind amplitude masks: Creating phase discontinuities

Hans Peter Herzig, Wilfried Noell, Myun Sik Kim, Toralf Scharf, Krishnaparvathy Puthankovilakam

Shaping of light fields behind amplitude and phase masks the basis the lithographic structure reproduction. The aerial image or better the intensity distribution defines the resolution of the structure to be printed. Contrast is the main parameter and to a ...

Ieee2016

Structured amplitude and phase fields behind microstructures: The quest for high contrast modulation at proximity

Hans Peter Herzig, Myun Sik Kim, Toralf Scharf, Johana Bernasconi, Krishnaparvathy Puthankovilakam

Microstructures can be used to realize repetitive and singular high contrast features at different distances behind a structure. For practical applications, the amplitude field needs to be considered. To realize defined amplitude features at long distances ...

Spie-Int Soc Optical Engineering2016

Transition of optical regime in miniaturized optical systems: light interactions beyond the refraction limit

Hans Peter Herzig, Myun Sik Kim, Toralf Scharf

We investigate the transition of optical regimes of miniaturized optical systems using two canonical examples, where the refraction of light limits the system performance. A ball-lens and a solid immersion lens (SIL) are considered, whose refractive respon ...

Spie-Int Soc Optical Engineering2016

Tunable cavity-coupled plasmonic perfect absorber for ultra-compact thermo-optical switching

Olivier Martin, Toralf Scharf, Shourya Dutta Gupta

2015

Multilevel Micro-Structuring of Glassy Carbon Molds for Precision Glass Molding

Hans Peter Herzig, Toralf Scharf, Karin Prater

Replication techniques for diffractive optical elements (DOEs) in soft materials such as plastic injection molding are state of the art. For precision glass molding in glasses with high transition temperatures, molds with extreme thermal resistivity, low c ...

Spie-Int Soc Optical Engineering2015

Interferometric study on Gouy phase anomaly of microlens array

Hans Peter Herzig, Wilfried Noell, Myun Sik Kim, Toralf Scharf

We investigate the Gouy phase anomaly of light in the focus of refractive plano-convex microlens arrays by using longitudinal-differential (LD) interferometry and a finite-difference time-domain (FDTD) simulation. We put emphasis on determining the amount ...

Spie-Int Soc Optical Engineering2015

Optical properties of waveguide-coupled nanowires for sub-wavelength detection in microspectrometer applications

Alessandro Crespi, Toralf Scharf

In this paper we experimentally investigate optical interactions between gold nanowires and fs-laser written waveguides in a view of applications for stationary-wave integrated Fourier-transform spectrometers in a movable mirror configuration. For this pur ...

European Optical Society2015

Multilevel Micro-Structuring of Glassy Carbon for Precision Glass Molding of Diffractive Optical Elements

Hans Peter Herzig, Toralf Scharf, Karin Prater

A consumer market for diffractive optical elements in glass can only be created if high efficient elements are available at affordable prices. In diffractive optics the efficiency and optical properties increases with the number of levels used, but in the ...

Spie-Int Soc Optical Engineering2015

Page 3 sur 6