A Flexible Chip-Film Patch and a Flexible Strain Gauge Sensor Suitable for a Hybrid System-in-Foil Integration

Flexible Ultrathin Chip-Film Patch for Electronic Component Integration and Encapsulation using Atomic Layer-Deposited Al2O3–TiO2 Nanolaminates

“…Flexible ultrathin systems with integrated electronics are arousing considerable interest not only for use in the automotive sector and IoT (internet of things) but also in the healthcare and medical fields. − With the help of surface systems, monitoring of vital parameters such as blood pressure and temperature, ions in sweat, as well as electrical signals will support point-of-care diagnosis and 24/7 monitoring for personalized medicine. − Combining diverse miniaturized sensors in an ultrathin device, the flexible film system is preferable but a technological challenge due to the variety of materials that are required. The chip-film patch (CFP) technology can be employed for this purpose as it encompasses ultrathin silicon chips and sensors embedded in a flexible polyimide film, namely, the polyimide PI-2611. , It provides suitable material and physical properties which makes it useful for the fabrication of such systems. The barrier properties of the films, however, are not sufficient, leading to a rapid failure of the embedded electronics when applied in harsh environments.…”

“…The chip-film patch (CFP) technology can be employed for this purpose as it encompasses ultrathin silicon chips and sensors embedded in a flexible polyimide film, namely, the polyimide PI-2611. 9 , 10 It provides suitable material and physical properties which makes it useful for the fabrication of such systems. The barrier properties of the films, however, are not sufficient, leading to a rapid failure of the embedded electronics when applied in harsh environments.…”

Flexible and Transparent Polymer-Based Optical Humidity Sensor

“…A variety of materials can be used for deposition on flexible substrates [3][4][5][6] but the ones that stands out due to easy deposition in the form of thin films, relatively low cost, tailored functionality and fast response are polymers [7]. A number of different polymers, suitable for use as flexible substrates for sensor applications, are reported in the literature, including polyethylene naphthalate (PEN) [8,9], polyethylene terephthalate (PET) [10][11][12][13][14], polydimethylsiloxane PDMS [15,16], polyimide PI [17][18][19][20], polyvinyl alcohol (PVA) [21][22][23][24], polylactide (PLA) [25,26], polyurethane (PU) [27,28], polysulfone (PSU) [29], polyetheretherketone (PEEK) [30,31] and polycarbonate (PC) [32], along with other materials such as common paper [33,34], flexible glass [35] and last, but not least, composite [36] and multilayer substrates [37]. Among the most commonly used flexible substrates, PI provides a great solution for devices with higher annealing temperatures; however, its amber color makes it unsuitable for devices that require transparency.…”