Miniaturization Efforts Research Articles

Vacuum levitation and motion control on chip

By isolating from the environment and precisely controlling mesoscopic objects, levitation in vacuum has evolved into a versatile technique that has already benefited diverse scientific directions, from force sensing and thermodynamics to materials science and chemistry. It also holds great promise for advancing the study of quantum mechanics in the unexplored macroscopic regime. However, most current levitation platforms are complex and bulky. Recent efforts in miniaturization of vacuum levitation set-ups have comprised electrostatic and optical traps, but robustness is still a concern for integration into confined settings, such as cryostats or portable devices. Here we show levitation and motion control in high vacuum of a silica nanoparticle at the surface of a hybrid optical–electrostatic chip. By combining fibre-based optical trapping and sensitive position detection with cold damping through planar electrodes, we cool the particle motion to a few hundred phonons. We envisage that our fully integrated platform is the starting point for on-chip devices combining integrated photonics and nanophotonics with precisely engineered electric potentials, enhancing control over the particle motion towards complex state preparation and read-out.

Volatile organic compounds in cancer and exhaled breath detection technology.

The detection of volatile organic compounds (VOCs) in breath has become a potential method for early cancer screening. Although this approach has attracted increasing attention from the both scientific and medical communities, it has not received appreciable traction in the clinical setting. There are two main obstacles. One involves the identification of specific biomarkers or combinations thereof especially in early cancer. The other is the lack the specialized equipment for breath analysis having the appropriate sensitivity and specificity. Using metabolomics, this chapter examines the research strategies involving gas biomarkers in cancer patient breath, cancer cell gas metabolites and synthetic biomarkers. We briefly explore gas biomarkers of seven cancers and introduce principles of detection and clinical application. Large analytical instruments and small sensor technology are highlighted. Challenges to VOC analysis are presented including clinical use, extraction and detection, miniaturization efforts and examination of metabolic VOC pathways. Finally, VOCs in cancer and in exhaled breath detection technology are summarized and future prospects explored.

A Single Oscillator-Excited Piezoelectric Actuator with Internal Contact Teeth.

The tail rotor of a helicopter, a crucial component, traditionally relies on a complex drive mode involving reducers and transmission gears. This conventional setup, with its lengthy transmission chain and numerous components, hinders miniaturization efforts. In response to this challenge, our paper presents a novel piezoelectric drive approach. Our objective was to suggest an innovative design capable of minimizing the components involved in the tail rotor drive. This design can be adjusted in size according to specific requirements and is effective up to a specified speed. Moreover, it facilitates the process of miniaturization and integration. The piezoelectric actuator's stator comprises an ultrasonic amplitude transformer, a ring, and three drive teeth. Utilizing the rod-like structure of the tail brace, the actuator is simplified by adhering ceramic sheets to it. The rotary piezoelectric actuator combines the first longitudinal mode of a rod with torus bending modes. The drive teeth then amplify the ring's displacement, facilitating rotor rotation. The resonant frequency and modal shape of the actuator were determined using the finite element method. Furthermore, an investigation was conducted to analyze the influence of the drive teeth positioning on the motion trajectory at the contact point. Theoretically, we infer that the declination angle of the drive tooth is a crucial parameter for achieving high speeds. To test our idea, we built three prototype stators with different drive tooth declination angles. Our actuator stands out for its cost-effectiveness, structural simplicity, compatibility with harmonic signals, and ease of miniaturization. It can be considered for the drive of the tail rotor of a microhelicopter.

Dengue: A mosquito borne disease

Dengue is a highly infectious disease of the tropical countries. It is caused by any of the 4 serotypes of dengue virus and is transmitted within humans through female Aedes mosquitoes. Dengue disease varies from mild fever to severe conditions of dengue hemorrhagic fever and shock syndrome. The optical, electrochemical, microfluidic, enzyme linked immunosorbent assay (ELISA), and smartphone-based biosensors are the main approaches which developed for detection of different biomarkers and serotypes of Dengue virus. Future efforts in miniaturization of these methods open the horizons for development of commercial biosensors for early-diagnosis of Dengue virus infection.

An Analysis of Miniaturization of 5G Massive MIMO Base Station Antenna

This paper reviews current works and efforts on the miniaturization of the 5G Massive MIMO base station antenna design. This paper first introduces the development of the Massive MIMO, with a proper mathematical illustration. Then, some conventional parameters are introduced to measure the performance of the antenna, with a connection to the miniaturization of the antenna. Specifically, two coefficients: the gain-to-volume ratio and isolation-to-volume ratio are constructed to measure the efforts in miniaturization. Tables that collect works in the literature are presented, with detailed comparisons among working situations. Then a general conclusion and future path of miniaturization are indicated. At last, the paper introduced the challenge and future of the miniaturization of the 5G Massive MIMO base station antenna.

Kendi Kendini Konfigüre Edebilen Robotik Bir Sistem için Mikro Ölçekte Elektromanyetik Dış Eyleyici Tabanlı Hareket Modeli Geliştirilmesi

Self-reconfigurable modular robots (SRMRs) are considered as autonomous kinematic machines that can change their own shape by rearranging the connectivity of their parts to perform new tasks, adapt to new circumstances or recover from damage. One of the main goals in SRMRs field is to reach to a million modules integrated self-reconfigurable systems. However, miniaturization efforts in self-reconfigurable modular robots bring some challenges such as storage and packaging. Developing externally actuated micro-robots can be a good alternative for miniaturization of SRMRs with the help of rapid enhancements in micro-manufacturing technologies encountered in the last decades. In this study a novel self-reconfiguration mechanism for micro-robots that are externally actuated by magnetic actuators is developed. In the study the motion of the magnets inside the microtubes under the effect of external magnetic field is investigated by using finite elements method. Dynamic model of the mechanism is obtained by using finite elements method and its applicability is exhibited by simulations. The results are compared with the theoretical values. It is envisioned that the study will contribute to micro-robotic systems in industry, defense industry and space missions as well as biomedical applications and medical robots.

Enabling point-of-need chemical detection by miniaturizing ion-trap mass spectrometry

There exists a wide-ranging need to provide both qualitative and quantitative chemical information in near-real time outside of the laboratory environment. In response to this need, efforts in recent years have focused on the transition of laboratory-based instruments for chemical analysis into field-portable forms. Of the many techniques for chemical analysis, mass spectrometry has been an active area for miniaturization efforts due to the quality of chemical information the technique can provide and its ability to operate either stand-alone or coupled with additional analytical techniques. In this mini-review, we provide an overview of what we term ‘point-of-need’ chemical measurements and summarize the various means by which they can be generated. We then transition to focus exclusively on the application of mass spectrometry and specifically on the miniaturization of ion-trap mass analyzers to enable this class of measurements. Examples are provided that demonstrate how this technology has been developed and used within the point-of-need application space.

Filter width affects the transmittance of patterned all-dielectric Fabry-Perot filters.

Thin-film all-dielectric Fabry-Perot filters can nowadays be patterned onto pixels of commercial imaging sensors used for spectral imaging. For these patterned filters, standard transfer-matrix thin-film calculations fail to predict their angular dependency. This Letter attributes the discrepancy to the finite filter size and is also, to my knowledge, the first study to analyze this for patterned all-dielectric Fabry-Perot filters. An angular spectrum approach that enables prediction without full knowledge of the filter design is introduced. In addition, the contribution of diffraction at normal incidence is characterized by a single dimensionless parameter. Knowing that patterned filter size matters and having a method to efficiently simulate its effect can guide ongoing miniaturization efforts and filter design.

Captivates

We present Captivates, an open-source smartglasses system designed for long-term, in-the-wild psychophysiological monitoring at scale. Captivates integrate many underutilized physiological sensors in a streamlined package, including temple and nose temperature measurement, blink detection, head motion tracking, activity classification, 3D localization, and head pose estimation. Captivates were designed with an emphasis on: (1) manufacturing and scalability, so we can easily support large scale user studies for ourselves and offer the platform as a generalized tool for ambulatory psychophysiology research; (2) robustness and battery life, so long-term studies result in trustworthy data individual's entire day in natural environments without supervision or recharge; and (3) aesthetics and comfort, so people can wear them in their normal daily contexts without self-consciousness or changes in behavior. Captivates are intended to enable large scale data collection without altering user behavior. We validate that our sensors capture useful data robustly for a small set of beta testers. We also show that our additional effort on aesthetics was imperative to meet our goals; namely, earlier versions of our prototype make people uncomfortable to interact naturally in public, and our additional design and miniaturization effort has made a significant impact in preserving natural behavior. There is tremendous promise in translating psychophysiological laboratory techniques into real-world insight. Captivates serve as an open-source bridge to this end. Paired with an accurate underlying model, Captivates will be able to quantify the long-term psychological impact of our design decisions and provide real-time feedback for technologists interested in actuating a cognitively adaptive, user-aligned future.

Evidence of weak Anderson localization revealed by the resistivity, transverse magnetoresistance and Hall effect measured on thin Cu films deposited on mica

We report the resistivity of 5 Cu films approximately 65 nm thick, measured between 5 and 290 K, and the transverse magnetoresistance and Hall effect measured at temperatures 5 K < T < 50 K. The mean grain diameters are D = (8.9, 9.8, 20.2, 31.5, 34.7) nm, respectively. The magnetoresistance signal is positive in samples where D > L/2 (where L = 39 nm is the electron mean free path in the bulk at room temperature), and negative in samples where D < L/2. The sample where D = 20.2 nm exhibits a negative magnetoresistance at B < 2 Tesla and a positive magnetoresistance at B > 3 Tesla. A negative magnetoresistance in Cu films has been considered evidence of charge transport involving weak Anderson localization. These experiments reveal that electron scattering by disordered grain boundaries found along L leads to weak Anderson localization, confirming the localization phenomenon predicted by the quantum theory of resistivity of nanometric metallic connectors. Anderson localization becomes a severe obstacle for the successful development of the circuit miniaturization effort pursued by the electronic industry, for it leads to a steep rise in the resistivity of nanometric metallic connectors with decreasing wire dimensions (D < L/2) employed in the design of Integrated Circuits.

Retracted] Design and Implementation of SOC‐Based Noncontact‐Type Level Sensing for Conductive and Nonconductive Liquids

In contrast to the existing electromechanical systems, the noncontact‐type capacitive measurement allows for a chemically and mechanically isolated, continuous, and inherently wear‐free measurement. Integration of the sensor directly into the container’s wall offers considerable savings potential because of miniaturization and installation efforts. This paper presents the implementation of noncontact (NC)‐type level sensing techniques utilizing the Programmable System on Chip (PSoC). The hardware system developed based on the PSoC microcontroller is interfaced with capacitive‐based printed circuit board (PCB) strip. The designer has the choice of placing the sensors directly on the container or close to it. This sensor technology can measure both the conductive and nonconductive liquids with equal accuracy.

Recent advances of triboelectric nanogenerator based applications in biomedical systems

AbstractTriboelectric nanogenerators (TENGs) are a promising power and sensing solution for biomedical applications attributed to the high electrical output and sensitivity with low‐cost and widely available materials. Here, the recent developments in TENG‐based biomedical applications with various structures and functionalities are discussed and summarized. Wearable TENGs perform well in motion and respiratory monitoring with excellent flexibility and low bio‐risks. Implantable TENGs enable interactions with the cardio‐cerebral vascular system and nervous system to monitor and treat different diseases with good biodegradability. Furthermore, explorations of TENGs in in vitro systems, including drug delivery, cellular proliferation and differentiation, are reviewed. Perspectives on the biomedical applications of TENGs are proposed based on investigation in this area in the past two decades. With continuous efforts in miniaturization and optimization of robustness, the TENG‐based self‐powered biomedical systems will definitely play an important role in the healthcare market in the future.image

Power Loss Shifted Design of Inductive Energy Transfer Systems

This article proposes a design procedure for power loss shifted inductive energy transfer systems. Based on adequately simplified mathematical circuit models for four different compensation topologies, the load dependent losses of the respective resonant circuits are presented. Power loss shifting is achieved for transfer coils and their compensation capacitors by adjusting the design operating area of the transfer system. As a result, this leads to asymmetrical reactive power and loss distribution on primary and secondary side. Design equations for coil systems and compensation capacitors with predictable transfer and loss behavior are provided. Strategies and equations for the determination of the operating area are given. The procedure can be adapted to many kinds of applications where power losses on either primary or secondary side of an inductive energy transfer system are key to be avoided and further miniaturization needs to be achieved. This strategy offers an additional degree of freedom that can be taken into advantage regarding the reduction of thermal heating or miniaturization efforts. A comparative metrological validation for the application of transcutaneous energy transfer shows that the losses of the secondary implanted components can be drastically reduced with the drawback of a decreased efficiency of the overall system.

Dengue virus: a review on advances in detection and trends - from conventional methods to novel biosensors.

Dengue virus is an important arbovirus infection which transmitted by the Aedes female mosquitoes. The attempt to control and early detection of this infection is a global public health issue at present. Because of the clinical importance of its detection, the main focus of this review is on all of the methods that can offer the new diagnosis strategies. The advantages and disadvantages of reported methods have been discussed comprehensively from different aspects like biomarkers type, sensitivity, accuracy, rate of detection, possibility of commercialization, availability, limit of detection, linear range, simplicity, mechanism of detection, and ability of usage for clinical applications. The optical, electrochemical, microfluidic, enzyme linked immunosorbent assay (ELISA), and smartphone-based biosensors are the main approaches which developed for detection of different biomarkers and serotypes of Dengue virus. Future efforts in miniaturization of these methods open the horizons for development of commercial biosensors for early-diagnosis of Dengue virus infection. Graphical abstract Transmission of Dengue virus by the biting of an Aedes aegypti mosquito, the symptoms of Dengue hemorrhagic fever and the structure of Dengue virus and application of biosensors for its detection.

Experimental Methods in Chemical Engineering: Mass Spectrometry—MS

AbstractMass spectrometry identifies the atomic mass of molecules and fragments in the gas phase. The spectrometer ionizes the molecules that then pass through an electric or magnetic field towards a detector. The field modifies the molecule's trajectory and we infer mass from its direction and velocity in a static field or from the stability of its path in a dynamic field. The electric current is amplified and a mass spectrum is generated from the location or timing of the signal from the detector, translated into a plot of the intensity as a function of the mass‐over‐charge ratio. It is field deployable, measures concentrations in real time with a temporal resolution better than 100 ms, and detection limits of fg. However, the signal drifts with time so we have to calibrate it as frequently as every hour. Calibrating requires multiple mixtures with varying concentrations to map the non‐linear response. The Web of Science Core Collection indexed over 60 000 articles that refer to MS (2016 and 2017) with applications ranging from permanent gas analysis, to identifying protein, forensic science, and natural products. The bibliometric software VOSViewer() identified four clusters of research related to MS: (1) proteomics, proteins, plasma, and metabolomics; (2) solid phase extraction together with gas chromatography; (3) tandem mass spectrometry and liquid chromatography; and (4) waste water and toxicity. We expect that the technique will continue to evolve with increased sensitivity, lower drift, and greater specificity. Miniaturization efforts should also continue in order to develop faster field deployable instruments.

Sharp GaN nanowires used as field emitter on active cantilevers for scanning probe lithography

Field emission scanning probe lithography (FE-SPL), which offers sub-10 nm resolution under ambient conditions, strongly relies on the quality and shape of the applied scanning probe tip. The technological development of AFM systems is also strongly connected to the performance of the cantilever. Thereby, the probes evolved from a simple passive deflection element to a complex MEMS through integration of functional groups, such as piezoresistive detection sensors and bimaterial based actuators. Here, the authors show actual trends and developments of miniaturization efforts for fabrication of active cantilevers with mounted sharp GaN and diamond nanowires. Both materials exhibit a higher mechanical stability than the typically applied silicon, which is supposed to increase tip lifetime and reproducibility of the lithography process. Furthermore, diamond offers a high chemical stability, whereas electrical and optical properties of GaN are tunable. They present preliminary results on the applicability of GaN nanowires and diamond tips, mounted on active scanning probes, as field emitter for FE-SPL. Therefore, field emission measurements, stability of field emission current, and exemplary high resolution features generated with the tested tips are shown.

Continuous extraction of proteins with a miniaturized electrical split-flow cell equipped with suspended splitters fabricated by dry film lamination

This article describes the development of an electrically driven Split-Flow Thin microsystem suitable for continuous-flow protein purification or concentration. We used a technology based on dry film resist, Ordyl SY 355, to realize 3D suspended structures in a microchannel (150 μm), including patterned Cr/Pt electrodes. The device developed for this research is the first electrical miniaturized dry film SPLITT system including suspended splitters and represents a good miniaturization effort of the ideal SPLITT cell, thus expanding the possibilities of realizing split-flow fractionation microfluidic network based on dry film technology. A suitable design and fabrication process for the realization of such a kind of device is reported. The purification/concentration performances of the system have been tested by infusing a Bovine Serum Albumin solution (0.1 wt percentage) through the inlets and evaluating the protein content at the outlets after the application of a pulsed electric potential. Experimental conditions have been changed during the testing phase, by varying the applied potential and the duty cycle of the square wave and the flow rate to find suitable conditions for protein extraction. The best-achieved purification/concentration rate was around 60%, measured as concentration difference between the two output channels normalized on the input concentration, thus confirming the viability of device for protein enrichment or purification for sample preparation. The device has a potential for integration in micro-TAS, thanks to its reduced dimensions, for applications involving protein analysis or bio-sensing in matrices including proteins interfering with the measurement.

Monolithic 300 Gb/s Parallel Transmitter in InP-Based Generic Photonic Integration Technology

In order to meet the constantly rising traffic demands in optical transport systems for data and telecommunications, compact, power efficient, and low-cost optical transmitters are needed that offer easy scalability toward higher transmission capacities. Photonic integrated circuit technology based on the InP material has long enabled the monolithic integration of tunable sources with modulators and opened the way toward large-scale wavelength-division multiplexed parallel transmitters. In this paper, we present the design and performance of a monolithic tunable 8 × 40 Gb/s parallel transmitter chip with more than 220 components and state-of-the-art capacity density metric. A generic photonic integration approach was followed, in which the transmitter is constituted from well-developed subcircuits and building blocks, facilitating its design and manufacturing. With the trend toward large-scale integration with increasing component densities and smaller chip sizes, proximity effects in form of crosstalk are limiting further miniaturization efforts. We analyze electrical, thermal, and optical crosstalk effects that are relevant to the transmitter design, discuss appropriate mitigation techniques, and indicate the limitations of the current technology.

Surface Chemical Tuning of Phonon and Electron Transport in Free-Standing Silicon Nanowire Arrays.

We report electronic and phononic transport measurements of monocrystalline batch-fabricated silicon nanowire (SiNW) arrays functionalized with different surface chemistries. We find that hydrogen-terminated SiNWs prepared by vapor HF etching of native-oxide-covered devices show increased electrical conductivity but decreased thermal conductivity. We used the kinetic Monte Carlo method to solve the Boltzmann transport equation and also numerically examine the effect of phonon boundary scattering. Surface transfer doping of the SiNWs by cobaltocene or decamethylcobaltocene drastically improves the electrical conductivity by 2 to 4 orders of magnitude without affecting the thermal conductivity. The results showcase surface chemical control of nanomaterials as a potent pathway that can complement device miniaturization efforts in the quest for more efficient thermoelectric materials and devices.

Compatibility of Spatially Coded Apertures with a Miniature Mattauch-Herzog Mass Spectrograph.

In order to minimize losses in signal intensity often present in mass spectrometry miniaturization efforts, we recently applied the principles of spatially coded apertures to magnetic sector mass spectrometry, thereby achieving increases in signal intensity of greater than 10× with no loss in mass resolution Chen et al. (J. Am. Soc. Mass Spectrom. 26, 1633-1640, 2015), Russell et al. (J. Am. Soc. Mass Spectrom. 26, 248-256, 2015). In this work, we simulate theoretical compatibility and demonstrate preliminary experimental compatibility of the Mattauch-Herzog mass spectrograph geometry with spatial coding. For the simulation-based theoretical assessment, COMSOL Multiphysics finite element solvers were used to simulate electric and magnetic fields, and a custom particle tracing routine was written in C# that allowed for calculations of more than 15 million particle trajectory time steps per second. Preliminary experimental results demonstrating compatibility of spatial coding with the Mattauch-Herzog geometry were obtained using a commercial miniature mass spectrograph from OI Analytical/Xylem.