We report, for the first time, a MEMS fabrication process for building atomically smooth, symmetric 3-D wineglass and spherical shell structures, using low internal loss materials, namely fused quartz and ultra low expansion titania silicate glass (ULE TSG). The approach consists of three major steps: (1) a deep fused quartz cavity etch, (2) plasma activated bonding of fused quartz to fused quartz or TSG and (3) a high temperature (up to 1700 • C) micro-glassblowing process. An in-house process capability of 1800 • C glassblowing with a rapid cooling rate of 500 • C/min was developed. Feasibility of the process has been demonstrated by fabrication of fused quartz and TSG micro-glassblown structures. Spherical and inverted-wineglass shells with self-aligned stem structures were fabricated using this process. The approach may enable new classes of TSG and fused quartz MEMS devices with extremely low surface roughness (0.23 nm surface average), intrinsically low thermoelastic dissipation (QTED > 5E+10), and highly symmetric structures (radial error < 500 ppm).

We demonstrate a new platform, convex lens-induced nanoscale templating (CLINT), for dynamic manipulation and trapping of single DNA molecules. In the CLINT technique, the curved surface of a convex lens is used to deform a flexible coverslip above a substrate containing embedded nanotopography, creating a nanoscale gap that can be adjusted during an experiment to confine molecules within the embedded nanostructures. Critically, CLINT has the capability of transforming a macroscale flow cell into a nanofluidic device without the need for permanent direct bonding, thus simplifying sample loading, providing greater accessibility of the surface for functionalization, and enabling dynamic manipulation of confinement during device operation. Moreover, as DNA molecules present in the gap are driven into the embedded topography from above, CLINT eliminates the need for the high pressures or electric fields required to load DNA into direct-bonded nanofluidic devices. To demonstrate the versatility of CLINT, we confine DNA to nanogroove and nanopit structures, demonstrating DNA nanochannel-based stretching, denaturation mapping, and partitioning/trapping of single molecules in multiple embedded cavities. In particular, using ionic strengths that are in line with typical biological buffers, we have successfully extended DNA in sub-30-nm nanochannels, achieving high stretching (90%) that is in good agreement with Odijk deflection theory, and we have mapped genomic features using denaturation analysis.single-molecule manipulation | polymer confinement | genomic mapping | CLIC imaging | nanotechnology N anoconfinement-based manipulation is a powerful approach for controlling the conformation of single DNA molecules on chip. When single polymer chains are squeezed into environments confined at length scales below their diameter of gyration in free solution, the polymer equilibrium conformation will be molded by the surrounding nanoscale geometry. Nanochannel arrays can be used for massively parallel extension of DNA across an optical field, serving as the basis for a highthroughput optical mapping of genomes (1, 2). More varied manipulations can be performed based on the design of the surrounding nanotopology, such as using nanocavities embedded in a nanoslit to trap single DNA molecules (3). Nanoconfinementbased manipulation, compared with competing techniques for single-molecule manipulation such as tweezer technology and surface/hydrodynamic-based stretching, has three key advantages (4): (i) It is highly parallel, providing the high throughput essential for mapping gigabase-scale mammalian genomes (1); (ii) it can be efficiently integrated with microfluidics to rapidly cycle molecules through the channel arrays for upstream/downstream pre-and postprocessing of DNA; and (iii) it does not require applied flow or electric force to maintain the DNA extension.Nanoconfinement-based approaches have, however, a key difficulty inherent to the use of nanoscale dimensions: the need to bridge length scales differing by up to 5 orders...

In this work, a facile and simple yet effective method to generate intrinsic autonomous self-healing polymers was developed, leading to new materials that can be easily fine-tuned both mechanically and chemically.

In this paper, we report Q-factor over 1 million on both n = 2 wineglass modes, and high-frequency symmetry ( f/ f ) of 132 ppm on wafer-level microglassblown 3-D fused silica wineglass resonators at a compact size of 7-mm diameter and center frequency of 105 kHz. In addition, we demonstrate for the first time, out-of-plane capacitive transduction on microelectromechanical systems wineglass resonators. High Q-factor is enabled by a high aspect ratio, self-aligned glassblown stem structure, careful surface treatment of the perimeter area, and low internal loss fused silica material. Electrostatic transduction is enabled by detecting the spatial deformation of the 3-D wineglass structure using a new out-of-plane electrode architecture. Out-of-plane electrode architecture enables the use of sacrificial layers to define the capacitive gaps and 10 μm capacitive gaps have been demonstrated on a 7-mm shell, resulting in over 9 pF of active capacitance within the device. Microglassblowing may enable batch-fabrication of high-performance fused silica wineglass gyroscopes at a significantly lower cost than their precision-machined macroscale counterparts.[ 2014-0251]Index Terms-Micro-glassblowing, 3-D MEMS, wineglass resonator, degenerate mode gyroscope, fused silica.

We demonstrate, for the first time, sub-1 Hz frequency symmetry in micro-glassblown wineglass resonators with integrated electrode structures. A new fabrication process based on deep glass dry etching was developed to fabricate microwineglasses with self-aligned stem structures and integrated electrodes. The wineglass modes were identified by electrostatic excitation and mapping the velocity of motion along the perimeter using laser Doppler interferometry. A frequency split ( f ) of 0.15 and 0.2 Hz was demonstrated for n = 2 and n = 3 wineglass modes, respectively. To verify the repeatability of the results, a total of five devices were tested, three out of five devices showed f < 5 Hz. Frequency split stayed below 1 Hz for dc bias voltages up to 100 V, confirming that the low frequency split is attributed to high structural symmetry and not to capacitive tuning. High structural symmetry (<1 Hz) and atomically smooth surfaces (0.23 nm Sa) of the resonators may enable new classes of high performance 3-D MEMS devices, such as rate-integrating MEMS gyroscopes.

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We demonstrate a lab-on-a-chip that combines micro/nano-fabricated features with a Convex Lens-Induced Confinement (CLIC) device for the in situ analysis of single cells. A complete cycle of single cell analysis was achieved that includes: cell trapping, cell isolation, lysis, protein digestion, genomic DNA extraction and on-chip genomic DNA linearization. The ability to dynamically alter the flow-cell dimensions using the CLIC method was coupled with a flow-control mechanism for achieving efficient cell trapping, buffer exchange, and loading of long DNA molecules into nanofluidic arrays. Finite element simulation of fluid flow gives rise to optimized design parameters for overcoming the high hydraulic resistance present in the micro/nano-confinement region. By tuning design parameters such as the pressure gradient and CLIC confinement, an efficient on-chip single cell analysis protocol can be obtained. We demonstrate that we can extract Mbp long genomic DNA molecules from a single human lybphoblastoid cell and stretch these molecules in the nanochannels for optical interrogation.

Confinement of single molecules within nanoscale environments is crucial in a range of fields, including biomedicine, genomics, and biophysics. Here, we present a method that can concentrate, confine, and linearly stretch DNA molecules within a single optical field of view using dielectrophoretic (DEP) force. The method can convert an open surface into one confining DNA molecules without a requirement for bonding, hydrodynamic or mechanical components. We use a transverse DEP field between a top coverslip and a bottom substrate, both of which are coated with a transparent conductive material. Both layers are attached using double-sided tape, defining the chamber. The nanofeatures lie at the “floor” and do not require any bonding. With the application of an alternating (AC) electric field (2 Vp-p) between the top and bottom electrodes, a DEP field gradient is established and used to concentrate, confine and linearly extend DNA in nanogrooves as small as 100-nm in width. We also demonstrate reversible loading/unloading of DNA molecules into nanogrooves and nanopits by switching frequency (between 10 kHz to 100 kHz). The technology presented in this paper provides a new method for single-molecule trapping and analysis.