R. Hanfoug - Academia.edu (original) (raw)

Papers by R. Hanfoug

2009 Third International Conference on Quantum, Nano and Micro Technologies, 2009

... Whole fabrication was carried out on standard 4 inch glass wafers in the clean room 10000 and... more ... Whole fabrication was carried out on standard 4 inch glass wafers in the clean room 10000 andMEMS lab of Delft University of Technology. ... The wafers were cleaned and transferred to MEMSlab where TMMF S2030 (Japan) dry film resist of 20µm thick was applied. ...

Integrated Photonics Research and Applications/Nanophotonics for Information Systems, 2005

A compact, ultra short, integrated polarization converter has been fabricated by optical lithogra... more A compact, ultra short, integrated polarization converter has been fabricated by optical lithography. Length of the converter is 125 µm, and 325 µm including tapers. Conversion efficiency is higher than 95% and loss is less than 1 dB.

Applied Surface Science, 2000

This paper compares the results obtained from wet oxidation in vapor mixture of methanol-water wi... more This paper compares the results obtained from wet oxidation in vapor mixture of methanol-water with those from wet oxydation water vapor of AlAs Sb layers in arsenic based structures matched on InP and on InAs subtrates. All the x 1-x Ž. structures have been made by molecular beam epitaxy. The quality of the resulting oxide layers AlOx were examined by Ž. Ž. means of scanning electron microscopy SEM , secondary ions mass spectrometry SIMS and resistance measurements of the structures. The results described in this report demonstrate that the addition of methanol into water vapor reduces the amount of antimony and arsenic in the oxidized layers of n-type structures.

A new design for a passive polarisation splitter is presented. The device consists of a di-rectio... more A new design for a passive polarisation splitter is presented. The device consists of a di-rectional coupler with tapered waveguides. The modal birefringence for 3rd order modes for TE and TM polarisations is employed to selectively couple one polarisation. Tapered waveguides in combination with a tapered coupling region are used to create more tol-erant designs. Because of the tapered region, the coupling condition is met for a larger width span, compatible with standard optical lithography. BPM simulations show a width deviation of 150 nm still yields a splitting better than 95%.

A tolerant single etch-step passive polarization split- ter on InP/InGaAsP is designed and fabric... more A tolerant single etch-step passive polarization split- ter on InP/InGaAsP is designed and fabricated. The device con- sists of a directional coupler with a wide and a narrow waveguide. Modal birefringence of the third-order modes for transverse electric (TE) and transverse magnetic (TM) polarizations is em- ployed to selectively couple one polarization. Tapering is applied to increase the tolerances. The devices are characterized, and the measurement results show good agreement with the beam- propagation-method simulations: a splitting ratio larger than 95% for a width range of around 100 nm and over a large wavelength range, covering at least the C-band.

The shortest integrated polarization converter realized by a fully optical lithography is reporte... more The shortest integrated polarization converter realized by a fully optical lithography is reported. It uses a single waveguide with one slanted side and one vertical wall. An optical 5x reduction wafer stepper with high numerical aperture (≥ 0.48) is used for exposure at 365 nm wavelength. Specified resolution is 0.4μm and overlay-accuracy is ≤60 nm. Vertical side of the converter is realized by reactive ion etching and slanted side by wet chemical etching. The polarization converter length is 125 μm and conversion efficiency is higher than 95%, which is better than the best known polarization converters on InP/InGaAsP until now.

VPI-simulation of a new all-optical wavelength converter is presented. It is based on interferome... more VPI-simulation of a new all-optical wavelength converter is presented. It is based on interferometric effects in two Mach-Zehnder interferometers (MZI), parallel connected by polarization components (PLCs). The PCs provide filtering between probe and control wavelengths, and polarization-insensitive operation

An array of integrated all-optical SOA-Mach-Zehnder switches is demonstrated. The alloptical swit... more An array of integrated all-optical SOA-Mach-Zehnder switches is demonstrated. The alloptical switches consist of MZIs with SOAs in the arms. For packaging a number of additional features are implemented: Spotsize converters are integrated to achieve a good overlap with cleaved fibers. For vertical alignment of the chips in the package, recesses are etched till a well defined level. For sub-micron horizontal alignment, cleave openings are lithographically defined and deeply wet-etched. First tests on chips packaged P-sideup, show large static extinction ratios (ER) and switching up to 40 Gb/s with an ER of more than 9 dB.

VPI-simulation of a new all-optical wavelength converter is presented. It is based on interferome... more VPI-simulation of a new all-optical wavelength converter is presented. It is based on interferometric effects in two Mach-Zehnder interferometers (MZI), parallel connected by polarization components (PCs). The PCs provide filtering between probe and signal wavelengths, and polarization-insensitive operation. Different efficiency values for PCs are supposed. Simulation shows wide operational range (10 dB) for the input power. Results obtained are also suitable for cascading these devices in optical networks (extinction ratio >10 dB, isolation >20 dB).

A designed 3 dB Multimode Interference (MMI) coupler optimized for low reflections is presented. ... more A designed 3 dB Multimode Interference (MMI) coupler optimized for low reflections is presented. The MMI is designed, processed and measured. For comparison purposes, MMIs with an original non-optimized layout are included on the same wafer. The measured results from both devices are compared. The results show reflection suppression in the case of the optimized MMI of more than 10 dB. In the same way a design for lx2 3 dB MMI is tested. The measured results also show reduced reflections.

In this paper, the effect on the optical bandwidth of couplers and the current settings used in S... more In this paper, the effect on the optical bandwidth of couplers and the current settings used in SOA-MZI WLC is presented. The optical bandwidth is found from the extinction ratio versus the wavelength. The bandwidth limitation found experimentally from an SOA-MZI with 1x2 couplers is in good agreement with the simulated bandwidth. The simulation shows that this limitation disappears in case 2x2 couplers are used.

Integrated Photonics Research and Applications/Nanophotonics, 2006

ABSTRACT A novel passive polarization splitter is fabricated, based on a tapered directional coup... more ABSTRACT A novel passive polarization splitter is fabricated, based on a tapered directional coupler. Modal birefringence is employed to selectively couple one polarization. The fabricated device shows splitting ratio larger than 95% in agreement with simulations.

A new design for an integrated passive polarization splitter and converter is presented. The devi... more A new design for an integrated passive polarization splitter and converter is presented. The device consists of a Mach-Zehnder Interferometer with polarization converters in both arms. The position of the converters is such that a phase difference of π radians occurs between TE and TM. This results in polarization splitting in the output coupler. The device is analyzed using the transfer matrix method and fabricated on InP/InGaAsP. First measurement results show a splitting ratio of approximately 10 dB and a conversion of >90 %. This device can be monolitically integrated with passive and active components.

The shortest integrated polarization converter realized by a fully optical lithography is reporte... more The shortest integrated polarization converter realized by a fully optical lithography is reported. It uses a single waveguide with one slanted side and one vertical wall. An optical 5x reduction wafer stepper with high numerical aperture (≥ 0.48) is used for exposure at 365 nm wavelength. Specified resolution is 0.4µm and overlay-accuracy is ≤60 nm. Vertical side of the converter

Emerging Lithographic Technologies XII, 2008

Semiconductor Science and Technology, 2001

ABSTRACT Low-threshold laser emission at room temperature of a GaSb-based quantum well structure ... more ABSTRACT Low-threshold laser emission at room temperature of a GaSb-based quantum well structure is reported in this paper. The optical and electrical confinement of the structure have been improved by inserting an aluminium oxide layer obtained by wet oxidation of AlAs in the upper confinement layer. The strains between the oxide layer and the contiguous layers (GaAs and GaSb) are compensated by an AlAs/GaAs superlattice. The resulting morphology of the oxidized AlAs layers is presented.

2009 Third International Conference on Quantum, Nano and Micro Technologies, 2009

... Whole fabrication was carried out on standard 4 inch glass wafers in the clean room 10000 and... more ... Whole fabrication was carried out on standard 4 inch glass wafers in the clean room 10000 andMEMS lab of Delft University of Technology. ... The wafers were cleaned and transferred to MEMSlab where TMMF S2030 (Japan) dry film resist of 20µm thick was applied. ...

Integrated Photonics Research and Applications/Nanophotonics for Information Systems, 2005

A compact, ultra short, integrated polarization converter has been fabricated by optical lithogra... more A compact, ultra short, integrated polarization converter has been fabricated by optical lithography. Length of the converter is 125 µm, and 325 µm including tapers. Conversion efficiency is higher than 95% and loss is less than 1 dB.

Applied Surface Science, 2000

This paper compares the results obtained from wet oxidation in vapor mixture of methanol-water wi... more This paper compares the results obtained from wet oxidation in vapor mixture of methanol-water with those from wet oxydation water vapor of AlAs Sb layers in arsenic based structures matched on InP and on InAs subtrates. All the x 1-x Ž. structures have been made by molecular beam epitaxy. The quality of the resulting oxide layers AlOx were examined by Ž. Ž. means of scanning electron microscopy SEM , secondary ions mass spectrometry SIMS and resistance measurements of the structures. The results described in this report demonstrate that the addition of methanol into water vapor reduces the amount of antimony and arsenic in the oxidized layers of n-type structures.

A new design for a passive polarisation splitter is presented. The device consists of a di-rectio... more A new design for a passive polarisation splitter is presented. The device consists of a di-rectional coupler with tapered waveguides. The modal birefringence for 3rd order modes for TE and TM polarisations is employed to selectively couple one polarisation. Tapered waveguides in combination with a tapered coupling region are used to create more tol-erant designs. Because of the tapered region, the coupling condition is met for a larger width span, compatible with standard optical lithography. BPM simulations show a width deviation of 150 nm still yields a splitting better than 95%.

A tolerant single etch-step passive polarization split- ter on InP/InGaAsP is designed and fabric... more A tolerant single etch-step passive polarization split- ter on InP/InGaAsP is designed and fabricated. The device con- sists of a directional coupler with a wide and a narrow waveguide. Modal birefringence of the third-order modes for transverse electric (TE) and transverse magnetic (TM) polarizations is em- ployed to selectively couple one polarization. Tapering is applied to increase the tolerances. The devices are characterized, and the measurement results show good agreement with the beam- propagation-method simulations: a splitting ratio larger than 95% for a width range of around 100 nm and over a large wavelength range, covering at least the C-band.

The shortest integrated polarization converter realized by a fully optical lithography is reporte... more The shortest integrated polarization converter realized by a fully optical lithography is reported. It uses a single waveguide with one slanted side and one vertical wall. An optical 5x reduction wafer stepper with high numerical aperture (≥ 0.48) is used for exposure at 365 nm wavelength. Specified resolution is 0.4μm and overlay-accuracy is ≤60 nm. Vertical side of the converter is realized by reactive ion etching and slanted side by wet chemical etching. The polarization converter length is 125 μm and conversion efficiency is higher than 95%, which is better than the best known polarization converters on InP/InGaAsP until now.

VPI-simulation of a new all-optical wavelength converter is presented. It is based on interferome... more VPI-simulation of a new all-optical wavelength converter is presented. It is based on interferometric effects in two Mach-Zehnder interferometers (MZI), parallel connected by polarization components (PLCs). The PCs provide filtering between probe and control wavelengths, and polarization-insensitive operation

An array of integrated all-optical SOA-Mach-Zehnder switches is demonstrated. The alloptical swit... more An array of integrated all-optical SOA-Mach-Zehnder switches is demonstrated. The alloptical switches consist of MZIs with SOAs in the arms. For packaging a number of additional features are implemented: Spotsize converters are integrated to achieve a good overlap with cleaved fibers. For vertical alignment of the chips in the package, recesses are etched till a well defined level. For sub-micron horizontal alignment, cleave openings are lithographically defined and deeply wet-etched. First tests on chips packaged P-sideup, show large static extinction ratios (ER) and switching up to 40 Gb/s with an ER of more than 9 dB.

VPI-simulation of a new all-optical wavelength converter is presented. It is based on interferome... more VPI-simulation of a new all-optical wavelength converter is presented. It is based on interferometric effects in two Mach-Zehnder interferometers (MZI), parallel connected by polarization components (PCs). The PCs provide filtering between probe and signal wavelengths, and polarization-insensitive operation. Different efficiency values for PCs are supposed. Simulation shows wide operational range (10 dB) for the input power. Results obtained are also suitable for cascading these devices in optical networks (extinction ratio >10 dB, isolation >20 dB).

A designed 3 dB Multimode Interference (MMI) coupler optimized for low reflections is presented. ... more A designed 3 dB Multimode Interference (MMI) coupler optimized for low reflections is presented. The MMI is designed, processed and measured. For comparison purposes, MMIs with an original non-optimized layout are included on the same wafer. The measured results from both devices are compared. The results show reflection suppression in the case of the optimized MMI of more than 10 dB. In the same way a design for lx2 3 dB MMI is tested. The measured results also show reduced reflections.

In this paper, the effect on the optical bandwidth of couplers and the current settings used in S... more In this paper, the effect on the optical bandwidth of couplers and the current settings used in SOA-MZI WLC is presented. The optical bandwidth is found from the extinction ratio versus the wavelength. The bandwidth limitation found experimentally from an SOA-MZI with 1x2 couplers is in good agreement with the simulated bandwidth. The simulation shows that this limitation disappears in case 2x2 couplers are used.

Integrated Photonics Research and Applications/Nanophotonics, 2006

ABSTRACT A novel passive polarization splitter is fabricated, based on a tapered directional coup... more ABSTRACT A novel passive polarization splitter is fabricated, based on a tapered directional coupler. Modal birefringence is employed to selectively couple one polarization. The fabricated device shows splitting ratio larger than 95% in agreement with simulations.

A new design for an integrated passive polarization splitter and converter is presented. The devi... more A new design for an integrated passive polarization splitter and converter is presented. The device consists of a Mach-Zehnder Interferometer with polarization converters in both arms. The position of the converters is such that a phase difference of π radians occurs between TE and TM. This results in polarization splitting in the output coupler. The device is analyzed using the transfer matrix method and fabricated on InP/InGaAsP. First measurement results show a splitting ratio of approximately 10 dB and a conversion of >90 %. This device can be monolitically integrated with passive and active components.

The shortest integrated polarization converter realized by a fully optical lithography is reporte... more The shortest integrated polarization converter realized by a fully optical lithography is reported. It uses a single waveguide with one slanted side and one vertical wall. An optical 5x reduction wafer stepper with high numerical aperture (≥ 0.48) is used for exposure at 365 nm wavelength. Specified resolution is 0.4µm and overlay-accuracy is ≤60 nm. Vertical side of the converter

Emerging Lithographic Technologies XII, 2008

Semiconductor Science and Technology, 2001

ABSTRACT Low-threshold laser emission at room temperature of a GaSb-based quantum well structure ... more ABSTRACT Low-threshold laser emission at room temperature of a GaSb-based quantum well structure is reported in this paper. The optical and electrical confinement of the structure have been improved by inserting an aluminium oxide layer obtained by wet oxidation of AlAs in the upper confinement layer. The strains between the oxide layer and the contiguous layers (GaAs and GaSb) are compensated by an AlAs/GaAs superlattice. The resulting morphology of the oxidized AlAs layers is presented.