Self-assembly of block-copolymers provides a route to the fabrication of small (size, <50 nm) and dense (pitch, <100 nm) features with an accuracy that approaches even the demanding specifications for nanomanufacturing set by the semiconductor industry. A key requirement for practical applications, however, is a rapid, high-resolution method for patterning block-copolymers with different molecular weights and compositions across a wafer surface, with complex geometries and diverse feature sizes. Here we demonstrate that an ultrahigh-resolution jet printing technique that exploits electrohydrodynamic effects can pattern large areas with block-copolymers based on poly(styrene-block-methyl methacrylate) with various molecular weights and compositions. The printed geometries have diameters and linewidths in the sub-500 nm range, line edge roughness as small as ∼45 nm, and thickness uniformity and repeatability that can approach molecular length scales (∼2 nm). Upon thermal annealing on bare, or chemically or topographically structured substrates, such printed patterns yield nanodomains of block-copolymers with well-defined sizes, periodicities and morphologies, in overall layouts that span dimensions from the scale of nanometres (with sizes continuously tunable between 13 nm and 20 nm) to centimetres. As well as its engineering relevance, this methodology enables systematic studies of unusual behaviours of block-copolymers in geometrically confined films.

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This study presents a 2.16 µW low-power third-order single-bit continuous-time delta-sigma modulator (CTDSM) for electrocardiogram (ECG) signal acquisition application. The proposed CTDSM uses an active-RC (A-RC) integrator as a first integrator and an improved linearized Gm-C integrator for the second and third integrators, respectively. The mixed-integrator structure helps to mitigate the trade-offs between power consumption and resolution. Moreover, a sourcedegenerated auxiliary differential pair circuit is used for the Gm-C integrators to improve their linearity. By using A-RC and Gm-C integrators together along with an improved-linearized Gm block, the total power consumption was measured as 2.16 µW with a peak signal-to-noise ratio of 80.1 dB, signal-to-noise, and distortion ratio of 78.4 dB, and a dynamic range of 81.4 dB with a bandwidth of 250 Hz. Furthermore, a real-time ECG signal was successfully captured in an ECG acquisition system that consisted a heart-rate sensor and a signal acquisition circuit, including the proposed CTDSM.

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Recently, rapid developments of compact mobile and wearable electronics and micro-medical devices are accelerating an increasing demand for miniaturized energy storages such as micro-supercapacitors. Graphene, a representative two-dimensional carbon material, has attracted enormous interest due to its excellent electrical, mechanical, physical and chemical properties. In particular, many efforts have been made to fabricate graphene-based micro-supercapacitors due to its large specific surface area and superior electrical conductivity. However, many of the attempted fabrication processes have drawbacks, such as complicated multiple-step procedures to create micron-sized interdigitated electrodes and usage of harmful or toxic chemicals during the etching process. In addition, high-temperature treatment is demanded to obtain high-quality graphene materials which is suitable for high-performance graphene-based micro-supercapacitors. Therefore, simple, cost effective and energy efficient strategies are still required for the fabrication of graphene-based micro-supercapacitors. Here, we report a simple, agile and facile method for the fabrication of three-dimensionally printed micro-supercapacitors with high-aspect-ratio electrode micro-arrays using a pneumatic printing technique in conjunction with an intense pulsed white light (IPWL) technology. By using this combined method, micron-sized electrode patterns can be easily printed on diverse substrates, and graphene- or metal oxide-based three dimensional micro-patterns can be fabricated within milliseconds by irradiating the IPWL on graphene oxide or metal oxide precursor patterns, which is exceptionally faster and easier than other graphene reduction and metal oxide formation methods. The as-prepared micro-patterns are further utilized as micro-supercapacitor electrodes, and their electrochemical properties and supercapacitive performance are investigated by means of cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy.