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Graphene is an extremely promising material for emerging nanoelectromechanical systems (NEMS) and sensors, but the transfer from its growth substrate to silicon substrates remains manual and laborious. We report a novel method for the transfer of large-area chemical vapor deposited (CVD) graphene from copper foil to a target wafer by adhesive wafer bonding using bisbenzocyclobutene (BCB) as an intermediate adhesive layer. The use of conventional wafer bonding equipment enables the scalable transfer of graphene and the realization of both supported and suspended graphene devices on wafer-scale. Our method circumvents manual handling of graphene after release from its growth substrate and avoids polymeric carrier layers, a well-known source of contamination. Hence, the proposed process promises the transfer of graphene with high quality and repeatability., QC 20200909

We present a low-confinement Si waveguide for 4.26 μm wavelength and applyit to sense CO2 concentrations down to 0.1 %. We demonstrate the highest reportedwaveguide sensitivity to CO2: 44% of the free-space sensitivity., QC 20190802

The electrical contact resistance at metal-graphene interfaces can significantly degrade the properties of graphene devices and is currently hindering the full exploitation of graphene's potential. Therefore, the influence of environmental factors, such as humidity, on the metal-graphene contact resistance is of interest for all graphene devices that operate without hermetic packaging. We experimentally studied the influence of humidity on bottom-contacted chemical-vapor-deposited (CVD) graphene-gold contacts, by extracting the contact resistance from transmission line model (TLM) test structures. Our results indicate that the contact resistance is not significantly affected by changes in relative humidity (RH). This behavior is in contrast to the measured humidity sensitivity (0.059 +/- 0.011 %/% RH) of graphene's sheet resistance. In addition, we employ density functional theory (DFT) simulations to support our experimental observations. Our DFT simulation results demonstrate that the electronic structure of the graphene sheet on top of silica is much more sensitive to adsorbed water molecules than the charge density at the interface between gold and graphene. Thus, we predict no degradation of device performance by alterations in contact resistance when such contacts are exposed to humidity. This knowledge underlines that bottom-contacting of graphene is a viable approach for a variety of graphene devices and the back end of the line integration on top of conventional integrated circuits.

A method for fabrication of a device (100) with an elongated structure (5), extending in a length direction (L) in a device layer (2) is described. The method comprises the steps of providing a planar first layer (1) on which the device layer (2) is supported, removing material in the device layer (2) to provide a first set of openings (3) through the device layer (2), and removing material from the planar first layer (1) under the elongated structure (5) through the first set of openings (3), wherein he arrangement of the first set of openings (3) is such that said support structure (4) is formed on which the elongated structure (5) is supported. The method also comprises the step of removing material from the device layer (2) to form the elongated structure (5) delimited by side surfaces (6)., QC 20210209

Silicon photonics is the study and application of integrated optical systems which use silicon as an optical medium, usually by confining light in optical waveguides etched into the surface of silicon-on-insulator (SOI) wafers. The term microelectromechanical systems (MEMS) refers to the technology of mechanics on the microscale actuated by electrostatic actuators. Due to the low power requirements of electrostatic actuation, MEMS components are very power efficient, making them well suited for dense integration and mobile operation. MEMS components are conventionally also implemented in silicon, and MEMS sensors such as accelerometers, gyros, and microphones are now standard in every smartphone. By combining these two successful technologies, new active photonic components with extremely low power consumption can be made. We discuss our recent experimental work on tunable filters, tunable fiber-to-chip couplers, and dynamic waveguide dispersion tuning, enabled by the marriage of silicon MEMS and silicon photonics., QC 20180404, VR-HET, XMEMS, M&M

QC 20190624

In MORPHIC, we are enhancing the capabilities of already established silicon photonics platform with low-power and non-volatile MEMS actuators to achieve programmability and re-configurability of the photonic circuits. The combining of high speed silicon photonics, non-volatile MEMS actuation, electronics controlled reconfigurable connectivity and high level design methodologies and programming interface in a package will lead to a complete Field-Programmable Photonic Integrated Circuits (FP-PIC) platform. Ultimately, technology platforms for both generic FP-PIC and Application-Specific Photonic Integrated Circuits (AS-PIC) with possibility of volume manufacturing will be demonstrated., QC 20190304, MORPHIC

With the progress and industrialization of photonic integrated circuits (PIC) in the past few decades, there is a strong urge towards design and prototyping in a fast, low-cost and reliable manner. In electronics, this demand is met through field programmable gate arrays (FPGA). In the Horizon 2020 MORPHIC (MEMS-based zerO-power Reconfigurable Photonic ICs) project, we are developing a reconfigurable PIC platform to address this demand in the field of photonics and to facilitate the path from idea towards realization for PIC designers and manufacturers., QC 20190312, MORPHIC

We experimentally demonstrate the first MEMS tunable photonic fiber-to-waveguide grating coupler, and apply it to electrostatically optimize the light coupling between an optical fiber and an on-chip silicon photonic waveguide. Efficient and stable fiber-to-chip coupling is vital for combining the high optical quality of silica fibers with the integration density of silicon photonics. Our device has the potential to lower assembly cost and extend device lifetime, by enabling electrical post-assembly adjustments., QC 20170301, VR-HET, CellRing

We demonstrate the first uncooled single-nanowire-based infrared bolometer to detect sub-mW optical signals up to MHz frequencies. The bolometer consists of a Pt nanowire on a suspended silicon hybrid-plasmonic cavity, and exhibits enhanced optical responsivity compared to nanowires on unstructured and non-suspended substrates. Low-cost monolithically integrated infrared detectors are needed for the rapidly growing field of silicon photonic sensors. The high speed of our nanobolometer enables advanced modulation schemes for noise reduction and avoidance of low-frequency thermal cross-talk, as well as power saving by pulsed operation. Furthermore, its simple integration and small footprint make it a cost effective detector for sensing applications., QC 20170124

QC 20180618

We design, fabricate and characterize sidewall corrugated Bragg gratings in a high confinement integrated optics lithium niobate platform, comprising submicrometric photonic wires, tapers and grating couplers to interface off-chip standard telecom optical fibers. We analyze the grating performance as band-rejection filter for TE-polarized signals in the telecom C-band, considering both rectangular and sinusoidal sidewall profiles, and demonstrate record extinction ratios as high as 27 dB and rejection bandwidths as narrow as 3 nm. The results show the potential for an efficient integration of novel photonic functionalities into low-footprint LiNbO3 nonlinear and electro-optical waveguide devices., QC 20180110