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This paper reports the development of a nano-gap vapor sensor that is capable of detecting an airborne target in a repeatable manner in near-zero static power consumption. The nano-gap sensor employed a matching gap distance of 5.8 nm to the lengths of both linkers and targets for selectivity. The nano-gap sensor was fabricated based on deposition and removal of a thin sacrificial layer via atomic-layer-deposition (ALD), and then coated with newly-synthesized linkers. The fabricated vapor sensor demonstrated the detection of a target gas (1, 5-Diaminopentane) or Cadaverine in a concentration of

This paper reports a new class of a gas sensor that utilizes the variation in bubble sizes when different gases are introduced into a liquid flow to identify gas types. The fabricated device enabled the detection of pentane (3μL) by producing the average bubble size of 130μm3, which showed size reduction by 2.4μm (1.7%) from the background bubble sizes (132.4μm) of nitrogen. The measurement also showed a preliminary correlation between the injection volume and the bubble size: increase in the injection volume of pentane from 3μL to 5μL (66.7% increases) resulted in the bubble size reduction from 1.7% to 2.1% (24% decreases) and the time span increase from 5s to 10s (100% increases).

This paper presents the first micro-scale circulatory column system that enables the extension of the effective column length through the circulatory loop without increasing the device volume, thus ultimately achieving ultra-high separation capacity. The circulatory column system consists of two 25-cm micro columns and six mini valves to produce circulatory Chromatographie separation. The fabricated column system (1) demonstrated the highest theoretical plate number per length-pressure of 206plates/m-kPa ever reported, enhancement in the detection capacity by 66% compared to the literature; (2) accomplished the longest effective micro column length of 5 meters ever reported; and (3) demonstrated the first micro-scale circulatory separation of target gas molecules up to 10 turns through a set of two 25-cm micro columns.

This paper presents a new technique for the fabrication of high resolution non-planar precision microshells for hemispherical resonating gyros via a poached-egg micromolding (PEM) method. In PEM, precision ball lenses are used as starting molds. Hemispherical shells are formed on the lenses using five major steps: (1) isotropic coating with sacrificial and shell layers, (2) stencil transfer of coated lenses to substrate, (3) shell top removal by anisotropic etching, (4) sacrificial layer etching and (5) release of the ball lens molds. Using PEM, we fabricated posted sputtered ultra-low-expansion glass hemispherical shells of 1 mm diameter and 1.2 μm thickness. The microshells have better than 120 ppm uniformity in thickness and less than ±0.125 μm deviation from a perfect sphere. The measured microshell resonant frequency at 100 mTorr was 17.32 kHz and the Q was ∼ 20,000.