김대형 교수

We report classes of electronic systems that achieve thicknesses, effective elastic moduli, bending stiffnesses, and areal mass densities matched to the epidermis. Unlike traditional wafer-based technologies, laminating such devices onto the skin leads to conformal contact and adequate adhesion based on van der Waals interactions alone, in a manner that is mechanically invisible to the user. We describe systems incorporating electrophysiological, temperature, and strain sensors, as well as trans

We have developed a simple approach to high-performance, stretchable, and foldable integrated circuits. The systems integrate inorganic electronic materials, including aligned arrays of nanoribbons of single crystalline silicon, with ultrathin plastic and elastomeric substrates. The designs combine multilayer neutral mechanical plane layouts and "wavy" structural configurations in silicon complementary logic gates, ring oscillators, and differential amplifiers. We performed three-dimensional ana

A remarkable feature of modern silicon electronics is its ability to remain physically invariant, almost indefinitely for practical purposes. Although this characteristic is a hallmark of applications of integrated circuits that exist today, there might be opportunities for systems that offer the opposite behavior, such as implantable devices that function for medically useful time frames but then completely disappear via resorption by the body. We report a set of materials, manufacturing scheme

Electrochemical analysis of sweat using soft bioelectronics on human skin provides a new route for noninvasive glucose monitoring without painful blood collection. However, sweat-based glucose sensing still faces many challenges, such as difficulty in sweat collection, activity variation of glucose oxidase due to lactic acid secretion and ambient temperature changes, and delamination of the enzyme when exposed to mechanical friction and skin deformation. Precise point-of-care therapy in response

Flexible and stretchable electronics and optoelectronics configured in soft, water resistant formats uniquely address seminal challenges in biomedicine. Over the past decade, there has been enormous progress in the materials, designs, and manufacturing processes for flexible/stretchable system subcomponents, including transistors, amplifiers, bio-sensors, actuators, light emitting diodes, photodetector arrays, photovoltaics, energy storage elements, and bare die integrated circuits. Nanomaterial

Blood glucose concentration is a key indicator of patients' health, particularly for symptoms associated with diabetes mellitus. Because of the large number of diabetic patients, many approaches for glucose measurement have been studied to enable continuous and accurate glucose level monitoring. Among them, electrochemical analysis is prominent because it is simple and quantitative. This technology has been incorporated into commercialized and research-level devices from simple test strips to we

Advances in materials, mechanics, and manufacturing now allow construction of high-quality electronics and optoelectronics in forms that can readily integrate with the soft, curvilinear, and time-dynamic surfaces of the human body. The resulting capabilities create new opportunities for studying disease states, improving surgical procedures, monitoring health/wellness, establishing human-machine interfaces, and performing other functions. This review summarizes these technologies and illustrates

Electronic systems that offer elastic mechanical responses to high-strain deformations are of growing interest because of their ability to enable new biomedical devices and other applications whose requirements are impossible to satisfy with conventional wafer-based technologies or even with those that offer simple bendability. This article introduces materials and mechanical design strategies for classes of electronic circuits that offer extremely high stretchability, enabling them to accommoda

Abstract New electronic materials have the potential to enable wearable computers, personal health monitors, wall‐scale displays and other systems that are not easily achieved with established wafer based technologies. A traditional focus of this field is on the development of materials for circuits that can be formed on bendable substrates, such as sheets of plastic or steel foil. More recent efforts seek to achieve similar systems on fully elastic substrates for electronics that can be stretch

A novel method to produce porous pressure-sensitive rubber is developed. For the controlled size distribution of embedded micropores, solution-based procedures using reverse micelles are adopted. The piezosensitivity of the pressure sensitive rubber is significantly increased by introducing micropores. Using this method, wearable human-machine interfaces are fabricated, which can be applied to the remote control of a robot.

All commercial forms of electronic/optoelectronic technologies use planar, rigid substrates. Device possibilities that exploit bio-inspired designs or require intimate integration with the human body demand curvilinear shapes and/or elastic responses to large strain deformations. This article reviews progress in research designed to accomplish these outcomes with established, high-performance inorganic electronic materials and modest modifications to conventional, planar processing techniques. W

Highly conductive and intrinsically stretchable electrodes are vital components of soft electronics such as stretchable transistors and circuits, sensors and actuators, light-emitting diode arrays, and energy harvesting devices. Many kinds of conducting nanomaterials with outstanding electrical and mechanical properties have been integrated with elastomers to produce stretchable conductive nanocomposites. Understanding the characteristics of these nanocomposites and assessing the feasibility of

An interactive human‐machine interface (iHMI) enables humans to control hardware and collect feedback information. In particular, wearable iHMI systems have attracted tremendous attention owing to their potential for use in personal mobile electronics and the Internet of Things. Although significant progress has been made in the development of iHMI systems, those based on rigid electronics have constraints in terms of wearability, comfortability, signal‐to‐noise ratio (SNR), and aesthetics. Here