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Microelectrodes are used in a wide range of applications from analytical electrochemistry and biomolecular sensing to in vivo implants. While a variety of insulating materials have been used to define the microelectrode active area, most are not suitable for nanoscale electrodes (

Specimen preparation remains a practical challenge in transmission electron microscopy and frequently limits the quality of structural and chemical characterization data obtained. Prevailing methods for thinning of specimens to electron transparency are serial in nature, time consuming, and prone to producing artifacts and specimen failure. This work presents an alternative method for the preparation of plan-view specimens using isotropic vapor-phase etching with integrated etch stops. An ultrathin amorphous etch-stop layer simultaneously serves as an electron transparent support membrane whose thickness is defined by a controlled growth process such as atomic layer deposition with sub-nanometer precision. This approach eliminates the need for mechanical polishing or ion milling to achieve electron transparency, and reduces the occurrence of preparation induced artifacts. Furthermore, multiple specimens from a plurality of samples can be thinned in parallel due to high selectivity of the vapor-phase etching process. These features enable dramatic reductions in preparation time and cost without sacrificing specimen quality and provide advantages over wet etching techniques. Finally, we demonstrate a platform for high-throughput transmission electron microscopy of plan-view specimens by combining the parallel preparation capabilities of vapor-phase etching with wafer-scale micro- and nanofabrication.

This paper presents new results from the first thermal accelerometer fabricated using Plasma Enhanced Atomic Layer Deposition. PEALD allows for ultrathin high-density platinum films that deliver excellent stability and accuracy [1]. We offer a 100x cross-section reduction relative to previous thermal accelerometers, thereby increasing the heating efficiency and decreasing thermal time constants [2,3,4,5]. The resistance thermometers and heaters capitalize on the properties provided by PEALD and Pt: extreme stability, high resistivity, and linear temperature coefficient of resistance (TcR) [6]. For a heater temperature rise of 150°C, this device has a raw sensitivity of 54 moC/g, excellent cross-axis isolation, and remarkably low drift.

Laterally actuated polycrystalline silicon nanoelectromechanical (NEM) relays with enhanced electrical properties are presented. Due to surface oxidation of polysilicon in room ambient conditions, the relays have a high contact resistance (> 1 GΩ) that requires high drain bias (3-5 V) to break through. The addition of a platinum sidewall coating reduces the on-resistance and the required drain bias to as low as 3 kΩ and 0.1 V, respectively. The platinum coating's stability is demonstrated by two tests: first, a contact-and-hold test where the relay passes current (~1μA) for up to 155 min and, second, a hot cycling test where the relay survives for over 108cycles . The NEMS relays are simulated using finite-element analysis, and the models are verified against experimental tests. Furthermore, the relays are configured and tested as a 2 : 1 multiplexer to show their potential as a digital logic component.

We demonstrate a temperature sensor consisting of a 2-D, Silicon (Si), Photonic Crystal (PC) attached to the facet of a standard single-mode optical fiber. The 2-D PC sensors are fabricated on standard Si wafers, using a single mask and a combination of isotropic and anisotropic etching, and microassembled onto the facets of the optical fibers by Si-welding. The temperature of the Si-PC sensor is monitored by measuring its reflectance spectrum in the 1250 to 1650 nm wavelength range. The measured reflectivity peak shift is 0.11 nm°C in the 100°C to 700°C temperature range. The observed spectral shift and temperature sensitivity are significantly higher than high-temperature fiber Bragg grating sensors, and comparable to long-period fiber gratings sensors. The high sensitivity, combined with compactness and robust structure, give these sensors strong potential for use in harsh environments.

Fiber optic sensors have applications in the measurement of a wide range of physical properties such as temperature, pressure, and refractive index. These sensors are immune to electromagnetic interference, made of high temperature dielectric materials and hence can be deployed in harsh environments where conventional electronics would fail. Photonic crystal (PC) fiber tip sensors are highly sensitive to changes in the refractive index and temperature while remaining compact and robust. In comparison to conventional fiber sensors such as fiber Bragg gratings (FBG) or long period fiber gratings (LPFG), they are attractive in several aspects. PC fiber tip sensors have better sensitivity to refractive index and temperature than FBG sensors and are have much smaller sensing volumes than FBGs and LPFGs. Their small size allows them to combine high sensitivity and structural robustness. The most attractive feature may be that PC fiber tip sensors also return a spectrally rich signal with independently shifting resonances that can be used to extract multiple physical properties of the measurand and distinguish between them. In this paper, we show that the PC fiber tip sensor is highly sensitive to the refractive index and temperature of the environment and that both parameters can be simultaneously determined using multiple wavelengths.

In this letter, we examine the role of the Ti capping layer in HfO x -based resistive random access memory (RRAM) devices on the memory performance. It is found that with a thicker Ti capping layer, the fresh device initial leakage current increases and as a result, the forming voltage decreases. In addition, with a thin Ti layer of

This paper presents the characterization of sealed microelectromechanical devices and their packaging fabricated in a polycrystalline 3C silicon carbide (poly-SiC) thin-film encapsulation process. In this fabrication technique, devices are sealed with a nominally 2-?m low-pressure chemical vapor deposition poly-SiC, and the device layer is simultaneously coated with a nominally 0.2- ?m poly-SiC thin film. Device characterization includes measurement of the resonant frequency and the quality factor of double-ended tuning-fork micromechanical resonators, which have a Si-SiC composite beam structure. Experimental results show that the pressure inside the packaging can be controlled from 447 Pa to 15.5 kPa with a 400°C annealing process. The frequency drifts of the encapsulated resonators are less than the frequency noise level (±10.6 ppm) measured over 29 days at 84.6°C ±0.1°C, which suggests that the poly-SiC thin-film packaging technique can offer hermetic packaging for various applications in microelectromechanical systems including inertial sensors. In addition to the packaging performance, the temperature coefficient of Young's modulus for poly-SiC is derived from the resonant-frequency change of resonators with temperature. The reduction of the quality factor due to the poly-SiC coating, predicted in the theoretical model, is confirmed by measurements.

Packaging of microelectromechanical systems (MEMS) is a critical step in the transition from development to commercialized product. This paper presents a thin-film encapsulation process that allows varying trench widths suitable for MEMS devices with lateral deflections as large as 20 ?m. The process involves the deposition and planarization of a sacrificial-oxide layer of up to 23 ?m thick, the deposition of a 20 ?m epitaxial-silicon sealing cap, the release of structures using hydrofluoric acid (HF) vapor, and the sealing of the structure at low pressure. Devices produced using this encapsulation method are capable of surviving standard backend processes such as wafer singulation and wire bonding. Among the numerous types of devices encapsulated, two different types of silicon MEMS resonators were fabricated. These functioning resonators demonstrate the ability of the process to successfully encapsulate devices, taking advantage of both large and small trench widths. Such a generalized fabrication platform greatly expands the possibilities of the wafer-scale encapsulation to numerous MEMS devices and retains the robustness necessary for backend processing.

We demonstrate a tunable infrared (IR) filter based on a patterned subwavelength grating in a metal film. The optical properties of the filter, including center wavelength and pass bandwidth, are dependent on the lithographically defined pattern of the grating. Additionally, the transmission intensity is controlled by using electrostatic actuation to bring the metal film into and out of contact with an underlying dielectric film. A maximum transmission of 72% is achieved, with a 4-to-1 rejection ratio at an actuation voltage of 46 V. The device holds promise for application to gas sensors and other IR sensor systems. The operating principle of this device can be extended to other regions of the electromagnetic spectrum beyond the mid-IR

We report on the demonstration of a microfabrication process which allows the release of suspended films or structures of varying sizes in which the release volume is predefined by i) lithographic patterning, ii) etch-stop deposition by atomic layer deposition (ALD), iii) refilling sacrificial layer into the empty volume, and iv) subsequent chemical mechanical planarization (CMP). We refer to this as an “etch sandbox,” which allows the user to process devices on a planarized substrate after completion of the sandbox. We demonstrate micrometer scale Al2O3 suspended membranes utilizing Al 2 O 3 as the etch-stop and polysilicon as the refill/sacrificial etch material. Within a single substrate and single release, defined etch volumes up to differing by up to a factor of 104 can be realized. Considering the flexibility of this process, suspended membranes with more complicated structure and composition could be developed in the future.

Waveguides are ubiquitous in silicon photonics. The density of waveguides is crucial to the integration density. We propose and demonstrate a waveguide superlattice that enables high-density waveguide integration at a half-wavelength pitch with low crosstalk.

Silicon photonics holds great promise for low-cost large-scale photonic integration. In its future development, integration density will play an ever-increasing role in a way similar to that witnessed in integrated circuits. Waveguides are perhaps the most ubiquitous component in silicon photonics. As such, the density of waveguide elements is expected to have a crucial influence on the integration density of a silicon photonic chip. A solution to high-density waveguide integration with minimal impact on other performance metrics such as crosstalk remains a vital issue in many applications. Here, we propose a waveguide superlattice and demonstrate advanced superlattice design concepts such as interlacing-recombination that enable high-density waveguide integration at a half-wavelength pitch with low crosstalk. Such waveguide superlattices can potentially lead to significant reduction in on-chip estate for waveguide elements and salient enhancement of performance for important applications, opening up possibilities for half-wavelength-pitch optical-phased arrays and ultra-dense space-division multiplexing.

We present the design, fabrication, and characterization of high quality factor and small mode volume planar photonic crystal cavities from cubic (3C) thin films (thickness ~ 200 nm) of silicon carbide (SiC) grown epitaxially on a silicon substrate. We demonstrate cavity resonances across the telecommunications band, with wavelengths from 1,250 - 1,600 nm. Finally, we discuss possible applications in nonlinear optics, optical interconnects, and quantum information science., Comment: 7 pages, 6 figures

CuPc-based organic thin-film transistor (OTFT) with high-k dielectric HfAlO as gate dielectric prepared by atomic layer deposition has been fabricated. Experimental results show that the HfAlO-OTFT has higher mobility, smaller sub-threshold slope and larger on/off ratio than the HfO 2 sample. All these should be attributed to the addition of Al into the HfO 2 film confirmed by X-ray photoelectron spectroscopy, resulting in improved dielectric and interfacial properties. Moreover, the reliablity of the device upon exposure to air is investigated.

The continued scaling in transistors and memory elements has necessitated the development of atomic layer deposition (ALD) of silicon nitride (SiNx), particularly for use a low k dielectric spacer. One of the key material properties needed for SiNx films is a low wet etch rate (WER) in hydrofluoric (HF) acid. In this work, we report on the evaluation of multiple precursors for plasma enhanced atomic layer deposition (PEALD) of SiNx and evaluate the film’s WER in 100:1 dilutions of HF in H2O. The remote plasma capability available in PEALD, enabled controlling the density of the SiNx film. Namely, prolonged plasma exposure made films denser which corresponded to lower WER in a systematic fashion. We determined that there is a strong correlation between WER and the density of the film that extends across multiple precursors, PEALD reactors, and a variety of process conditions. Limiting all steps in the deposition to a maximum temperature of 350 °C, it was shown to be possible to achieve a WER in PEALD SiNx of 6.1 Å/min, which is similar to WER of SiNx from LPCVD reactions at 850 °C.

We describe the fabrication of a double-layer silicon photonic crystal using self-aligned CMOS-compatible processes and its assembly on a single mode fiber using a wafer template and epoxy bonding. The fiber sensor has sharper resonances and higher temperature sensitivity than the previously-reported single-layer sensor. The new assembly method facilitates batch-production of the sensor and allows for extension to high temperature measurement.

While the literature is rich with data for the electrical behavior of nanotransistors based on semiconductor nanowires and carbon nanotubes, few data are available for ultrascaled metal interconnects that will be demanded by these devices. Atomic layer deposition (ALD), which uses a sequence of self-limiting surface reactions to achieve high-quality nanolayers, provides an unique opportunity to study the limits of electrical and thermal conduction in metal interconnects. This work measures and interprets the electrical and thermal conductivities of free-standing platinum films of thickness 7.3, 9.8, and 12.1 nm in the temperature range from 50 to 320 K. Conductivity data for the 7.3 nm bridge are reduced by 77.8% (electrical) and 66.3% (thermal) compared to bulk values due to electron scattering at material and grain boundaries. The measurement results indicate that the contribution of phonon conduction is significant in the total thermal conductivity of the ALD films.

We present a sensor capable of detecting solution-based nanoparticles using an optical fiber tip functionalized with a photonic crystal cavity. When sensor tips are retracted from a nanoparticle solution after being submerged, we find that a combination of convective fluid forces and optically-induced trapping cause an aggregation of nanoparticles to form directly on cavity surfaces. A simple readout of quantum dot photoluminescence coupled to the optical fiber shows that nanoparticle presence and concentration can be detected through modified cavity properties. Our sensor can detect both gold and iron oxide nanoparticles and can be utilized for molecular sensing applications in biomedicine., Comment: 13 pages, 5 figures

We describe a double-layer monolithic silicon photonic crystal (PC) fiber tip sensor. The PC is fabricated using wafer-scale Si processing and epoxy bonding to the fiber. The sensor has sharper resonances and higher sensitivity to refractive index than previously-reported single-layer PC fiber tip sensors. The bonding technique enables batch production.

Microfabricated thermionic emitters form a crucial part of thermionic energy converters, which could find applications in future concentrated solar thermal power plants. Here we report a new stress-relieved design for p-doped and n-doped silicon carbide (SiC) emitters, measurements of their thermionic emission and work functions at temperatures of up to 2900K, and the effect of optical irradiation on both types of SiC emitters. We also report the first observation of the photon-enhanced thermionic emission (PETE) in a thin-film microfabricated emitter.

Laterally actuated nanoelectromechanical (NEM) relays are implemented using a polysilicon structural layer with hafnium oxide (HfO 2 ) and platinum dual sidewall layers. Atomic layer deposition (ALD) HfO 2 provides electrical isolation between the polysilicon beam structure and the sputtered platinum conductive channel. Dual sidewall devices are demonstrated using a Y-shaped device with two contacts that connect source and drain upon actuation. Fabricated devices show up to 1µA current passing between source and drain without beam current flow, confirming successful isolation.

Unlike a traditional capacitive pressure sensor, which uses the entire deflectable diaphragm as the electrode, this paper proposes the use of reduced electrode area to increase the fractional capacitance change and reduce the device's sensitivity to package stresses. Therefore, in addition to the low temperature sensitivity inherent in capacitive sensing, the proposed pressure sensor helps relax signal conditioning requirements typically associated with capacitive sensor interface circuitry.

We present a technique to increase carbon nanotube (CNT) density beyond the as-grown CNT density. We perform multiple transfers, whereby we transfer CNTs from several growth wafers onto the same target surface, thereby linearly increasing CNT density on the target substrate. This process, called transfer of nanotubes through multiple sacrificial layers, is highly scalable, and we demonstrate linear CNT density scaling up to 5 transfers. We also demonstrate that this linear CNT density increase results in an ideal linear increase in drain−source currents of carbon nanotube field effect transistors (CNFETs). Experimental results demonstrate that CNT density can be improved from 2 to 8 CNTs/μm, accompanied by an increase in drain−source CNFET current from 4.3 to 17.4 μA/μm.

HfO x /AlO x bi-layer RRAM devices were fabricated with the atomic layer deposition (ALD) method. Compared with the single-layer HfO x devices, the bi-layer devices showed less variation of the switching voltages and resistances. Inspired by the fact that varying reset stop voltage in a DC sweep can achieve multilevel high resistance state, two equivalent pulse programming schemes were proposed: one linearly increases the reset pulse amplitudes; the other exponentially increases the reset pulse width. The transient current response waveform measurement suggests the former scheme is a more energy efficient programming method.

This paper presents an uncooled infrared bolometer using a metal thin film that is formed by atomic layer deposition (ALD). Nanometer-thick freestanding layers enabled by ALD have the potential to improve the performance of bolometers with achieving low thermal conductance and near optimal optical properties. The fabrication and characterization of the first implementation are described as well as the electrical properties of ALD platinum films.

This paper considers the electromechanical response of electrostatic actuators that are driven by both voltage and charge. The model system is an electrostatic actuator in which the suspended electrode is subjected to a driving voltage and the fixed electrode, which is electrostatically floating, is loaded by charge. The response of the system is analyzed using energy methods, and it is shown that the system has two distinct pull-in voltages. It is also shown that the amplitude of charge on the floating electrode is proportional to the average of these two pull-in voltages. Test-actuators were designed, fabricated, and characterized, and their measured response validates the theoretical predictions. A nondisruptive measurement of charge is proposed and demonstrated which enables to monitor charge decay over time.

We demonstrate that monolithic 2-dimensional silicon photonic crystals confined to the facet of single-mode optical fibers are capable of determining refractive index and temperature of a sample simultaneously from reflectivity measured at two different wavelengths.

The use of Photonic Crystals (PCs) to control electromagnetic fields enables unprecedented scaling of low-loss, free-space optical devices. In this paper, we describe the operation, design, and fabrication of PC mirrors, and demonstrate their applications in microoptical systems.

This paper reports on lateral nanoelectromechanical (NEM) relays based on variations of a two- or three-mask titanium nitride (TiN) sidewall stringer process. Electrically isolated TiN perimeter beams are fabricated from stringers formed on the inside walls of polysilicon trenches, yielding 200nm wide TiN fins and 200nm gaps; these dimensions are 3X smaller than the resolution limit of the optical lithography tool (600nm) utilized. The reduction in the operating voltage is about a factor of 5 compared to 600nm wide polysilicon beams. Simple scaling could potentially enable sub-1V operation. Five-terminal NEM relays demonstrate successful switching in both directions over 1000 DC-sweep cycles with low drain bias (100mV).

We demonstrate that monolithic 2-dimensional photonic crystals (PCs) confined to the facet, or tip, of single-mode optical fibers can be designed as highly sensitive temperature sensors. Monolithic 2-D photonic-crystals are fabricated on silicon wafers and subsequently released and micro-assembled onto the tip of optical fibers. The PC's reflection spectrum is modulated by the temperature of the sensor and its environment and shows sensitivity comparable to Fiber Bragg Gratings (FBGs). In contrast to FBGs, the compact sensing element is localized at the tip of the fiber and the active sensor element is a disk of 10µm diameter and 480 nm thickness. The sensor system is made of robust, high-temperature dielectric materials and therefore has the potential to be used for many applications including measurements in harsh environments.

We developed a new process for laser-printing a thin-film magnetic-polymer composite microstructural material directly onto planar silicon substrates and characterized its magnetic and mechanical properties. Using this technique we fabricated cantilever beams 100–2000µm long, 100–500µm wide, and 6–8µm thick. An external magnet was used to demonstrate actuation via magnetic field gradient forces, and a scanner was constructed able to deflect a laser beam 3°. This technique takes advantage of advances in commercial laser printing technology and is suitable for low-cost, low-temperature, large-area MEMS devices and rapid MEMS fabrication on a variety of substrates.

Packaging of microelectromechanical systems (MEMS) is a critical step in the transition from product development to production. This paper presents a robust, hermetically-sealed encapsulation method that can accommodate many traditional MEMS devices by allowing large lateral deflection structures within a clean environment. Using the new technology described in this paper, trench widths ranging from 1?m to 100?m were successfully encapsulated at the wafer level while maintaining devices as thick as 20?m. Devices produced with this method have proven durable enough to withstand harsh post-processing such as dicing and wire bonding. Two different types of MEMS resonators are also discussed, demonstrating the use of both large and small trench widths within the encapsulation.

We report on experimental measurements of the optical properties of thin films of poly-crystalline silicon carbide (poly-SiC) deposited by means of low pressure chemical vapor deposition (LPCVD). Measurements in the mid-IR region of the EM spectrum show strong dependence of both far field transmission and surface modes upon the deposition conditions including doping levels, ratio of dichlorosilane (DCS) to 1,3 disilabutane (DSB), and anneals performed on the film. We observe the link between the relative strength of near field phonon polariton resonances, the appearance of a polariton gap, and the achievement of extraordinary optical transmission (EOT).

This paper describes a microelectromechanical resonator interface to a nanomechanical structure. Our approach to microresonator-nanowire integration employs silicon nanowires as mechanical tuning elements, which perturb the frequency response of the resonator system. Two coupling configurations were designed and tested, the first with a nanowire beam coupled to the maximum displacement points of clamped-clamped microresonators and the second with a coupling beam attached 1.5 mum away from the anchors of the bending mode resonators. A focused-ion-beam (FIB) tool was used to tune the frequency response of the coupled systems. Finally a nanowire coupled bandpass filter with a 3 dB bandwidth about 120 kHz at 17.9 MHz was demonstrated.

The operation and performance of complementary nanoelectromechanical (CNEM) logic gates are investigated. NEMS structures featuring dimensions 2 to 3 orders of magnitude smaller than the present MEMS relays are considered. Various metals are benchmarked to silicon as the cantilever beam material. We show that the CNEM inverters featuring laterally actuated beams, 10 nm gap and low density materials such as Si or Al can achieve nanosecond pull-in delay and sub-0.1 fJ switching energy at VDD = 1.5 V while occupying an area as small as 0.03 mum2.

We report on the experimental observation of the effect of periodic hole arrays in the infrared reflection spectra of suspended polycrystalline silicon carbide (poly-SiC) membranes. The poly-SiC was deposited by low pressure chemical vapor deposition (LPCVD), patterned with contact photolithography, and etched by reactive ion etching (RIE). The spectra are shown to be strongly dependent on the pitch and aperture size of the hole arrays, indicating poly-SiC has promise as a mid-IR optical material.

We report on the effect of stacking a pair of metallic subwavelength hole arrays on the extraordinary transmission spectrum. A novel fabrication process was developed to create a self-aligned vertical stack of subwavelength metal gratings with precise control of the separation between the two metal films. For separations within the coupling region of the evanescent surface modes of the metal films, minor sharpening of the transmission filter characteristics was observed.

This paper reports on the integration of subwavelength metal gratings with surface micro-machined, electrostatic MEMS actuators to produce a tunable electromagnetic filter. Metal films perforated with periodically-spaced subwavelength diameter holes have been shown to transmit light with greater efficiency than predicted by classical models for evanescent propagation. Additionally, the field propagation shows strong dependance on the index of refraction on either surface of the metal. This characteristic performance leads to electric field enhancement at the apertures in the metal, an effect that holds promise for nanoscale optical sensors. We describe our work on the integration of MEMS electrostatic actuators with patterned metal films that were interrogated using infrared (IR) radiation. We report a transmission modulation factor of 7 with an actuation voltage of 46V.

The first reported square array of subwavelength holes patterned with nanoimprint lithography in an aluminum film is presented. Optical modes vary linearly with the refractive index of the fluid in contact with the aluminum grating

Metal films perforated with periodically-spaced subwavelength diameter holes have been shown to transmit light with greater efficiency than predicted by classical models for evanescent propagation. This transmission mechanism is caused either by the coupling of light to surface plasmon polariton modes on the surfaces of the metal film or by diffraction patterns in the lateral evanescent modes of electromagnetic field. Regardless of the root cause, this characteristic performance leads to electric field enhancement at the apertures in the metal, an effect that holds promise for nanoscale optical sensors. In particular, the propagation of these modes is very sensitive to changes in the index of refraction on either surface of the metal. This paper will describe our work on patterned metal films which are interrogated using infrared (IR) radiation. These metal gratings are fabricated using a surface micromachining process, allowing MEMS actuators to be integrated alongside the optically-active surface. The integration of MEMS structures with subwavelength optical structures can be used to create structures whose optical properties are modulated by changes in the position of a MEMS element, resulting in mechanical sensors and tunable optical filters. We will describe structures in which small changes in the separation between the metal film and a dielectric substrate result in large changes in the optical transmission and reflection spectra.

We report on an Optical Add/Drop Multiplexer designed from a single Arrayed Waveguide Grating and a MEMS optical switch. Three different MEMS switches were tested, the most promising being a potentially integrable binary actuator array.

We demonstrate embedding of chiplets into wafers to bypass the monolithic integration challenges of combining micro-mechanical devices with active circuitry. Dry alignment is provided by passive guide tabs, which are created through polysilicon refill of frontside etched trenches. The guide tabs are compatible with further processing on the wafer. Precision chiplets are created by through-wafer etching. After chiplet drop-in, optical detection provides feedback of chiplet jamming, and horizontal driving of the chiplets finishes the zero insertion force assembly process. We demonstrate less than 2.5 µm of chiplet to substrate alignment error. Theoretical scaling of alignment accuracy reaches numbers comparable to photolithography, allowing high density interconnects for heterogeneous integration without precision manipulators.

We demonstrate a simple and rapid epoxy-based method for transferring photonic crystal cavities to the facets of optical fibers. Passive Si cavities were measured via fiber taper coupling as well as direct transmission from the fiber facet. Active quantum dot containing GaAs cavities showed photoluminescence that was collected both in free space and back through the original fiber. Cavities maintain a high quality factor (2000-4000) in both material systems. This new design architecture provides a practical mechanically stable platform for the integration of photonic crystal cavities with macroscale optics and opens the door for novel research on fiber-coupled cavity devices., Comment: 10 pages, 5 figures

This article describes direct laser printing of thin-film polymer onto rigid substrates for use as an etch mask or liftoff layer in patterning on-chip electrical components. Using this technique, the authors fabricated planar spiral inductors of 12×12mm2 with 2.5–5.5 turns producing series inductance Ls=80–180nH as well as planar interdigitated capacitors of 10×10mm2 with two to nine fingers producing series capacitance Cs=100–1600nF. This technique is a low cost, low temperature, rapid turn around, maskless, resist-free means of patterning device features as small as 130μm.

We present high quality factor (Q s 1,000) photonic crystal cavities in cubic silicon carbide (3C-SiC) films grown directly on silicon. We show results in shifted-L3 and nanobeam cavity geometries for applications in nonlinear and quantum photonics.

Single-cell interrogation at the nanoscale can take on many forms—namely, pillars1, tubes2–5, and wires6–8 as probes for gentle insertion into a cell’s interior, allowing for studies on single-cell cargo delivery4, electrochemistry3 or electrophysiology1, and optical signaling9–10. However, optical probes such as nanowires9 or tapered fibers10 are passive in nature and have only served as conduits to guide light into and out of a cell. Here we demonstrate a nanobeam photonic crystal (PC) cavity as an advanced cellular nanoprobe, active in nature, and configurable to provide a multitude of actions for both intracellular sensing and control. Our semiconductor nanocavity probes emit photoluminescence (PL) from embedded quantum dots (QD) and sustain high quality resonant photonic modes inside cells. The beams can be loaded in cells and tracked for days at a time, with cells undergoing regular division with the beams. Furthermore, we present in vitro label-free protein sensing with our probes as a path towards real-time biomarker detection in single cells.