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In this paper we demonstrate the use of a CMOS infra-red emitter in a low power Non Dispersive Infra Red (NDIR) based carbon dioxide sensor for application in domestic boilers. Compared to conventional micro-bulbs as IR wideband sources, CMOS IR emitters offer several advantages: They are faster, smaller, have lower power consumption and can have integrated circuitry. The emitter is a 1.16 mm × 1.06 mm chip with an integrated FET drive and consists of a tungsten heater fabricated in a CMOS process followed by Deep Reactive Ion Etching (DRIE) to form a thin membrane to reduce power consumption. The NDIR sensor consists of the emitter and a commercial detector placed 5 mm apart in a simple tube. Operating the emitter at 10 Hz with a power consumption of only 40 mW, the sensor was measured in the range of 6-14% by volume of CO 2 , showing a resolution of 0.5%, a response time of 20 s, and low cross-sensitivity to humidity.

Printed circuit board (PCB) assemblies must fit into unusual spaces for many real-life, high temperature applications such as sensors and actuators. This paper details the design and manufacture of a complex control circuit for a jet engine fuel flow valve. “Origami” was needed to fit this control circuitry into the tight space in the valve, this was achieved using a high temperature flex rigid PCB assembly. The valve was mounted on a hot section of the engine, and the assembly was tested for its capability to operate at 178°C and withstand multiple thermal cycles of −55°C and 175°C during its operational life. Various component joining media were investigated to extend the life of the assembly. The project also developed a one-time programmable (OTP) memory aimed at up to 300°C operation for on board memory to provide calibration data or boot memory for high temperature microcontrollers or processors. The device was based on Micro-Electro-Mechanical Systems (MEMS) technology.

Autonomous systems for healthcare and sports applications benefit largely from a small form factor, as minute dimensions result in maximal mobility and comfort. By embedding a commercially available IC in a flexible circuit board (FCB), the overall size of a system can be reduced. This work presents the process of thinning and packaging an IC in a flexible interposer, and the embedding thereof in a FCB. To illustrate the potential of this technology towards miniaturization, a commercially available RF transceiver ZL70102 was packaged and embedded, thus realizing a volume reduction of 60%. I ntroductionResearch in the field of healthcare and sport monitoring tends to focus on the development of smart devices, where the output of multiple sensors is combined with the functionality of a microcontroller, memory and an RF transceiver for wireless communication to a base station or other nodes in the Body Area Network (BAN). The picture is often completed with a battery or energy harvester, thus providing an autonomous solution which enables the user or patient to monitor his/her health with a higher effectiveness and precision. Conventional technology often results in bulky solutions, and miniaturization of these systems only seems to be possible at the expense of functionality, autonomy and comfort.This paper reports on the development of a versatile packaging technology which allows integrating commercially available ICs into a miniature package by embedding the chip into a flexible circuit board (FCB). This action then allows rerouting the passives on top of the IC, which results in a system with a smaller form factor, breaking the boundaries imposed by SMD technology and fine pitch packages.

A polymer based electronic packaging system has been developed that is capable of operating at temperatures over 175°C and up to 225°C. This system is being developed to be a lead free, non-hermetic and able to deliver miniature or functionally dense circuits. It will be suitable for sensor systems where amplification, signal digitisation and autonomy are important whilst operating in a harsh environment such as high temperature.