Hybrid printed electronic systems
Printed, flexible sensor systems are promising for smart labels and wearable electronics. In certain high performance applications complex computational functionalities are desirable, such as signal processing and high speed wireless communication, which are readily available in conventional silicon devices. In order to combine the benefits of flexible, distributed sensors and the high performance of silicon electronics we have developed a hybrid fabrication platform that allows for organic/printed electronics alongside pre-formed microelectronic devices using digital fabrication. This approach allows for high performance sense-and-transmit systems to be developed incorporating organic devices with little change in mechanical flexibility due to the use of small, low profile integrated circuits. This report describes a hybrid sensing platform which reads in data from multiple printed sensors based either on organic or nanoparticle semiconductors (resistive light and heat sensors in this case), processes that information at high resolution and transmits it wirelessly to a separate reading device. Starting with a flexible PEN substrate, printed components are used for sensing, multiplexing, interconnection, the antenna and ancillary passive elements, with low-profile microelectronic devices used for analogue-to-digital conversion, processing and wireless transmission. As the microelectronic components are driven at a potential less than 5 V it is desirable for all other elements to operate at the same voltage. For example, for multiplexing of multiple sensor signals, we have developed complementary printed field-effect transistors based on organic semiconductors using a high-k composite dielectric. These devices can be operated at low-voltage (complementary inverters show gain > 1 at a 2 V input). Other relevant issues that will be discussed include impedance matching between the sensors and circuits, robust printed interconnection of the chips, interface electronics between printed and discrete components, and power constraints.
Whiting, G. L.; Schwartz, D. E.; Ng, T.; Krivacic, B.; Tuganov, A. V.; Veres, J. Hybrid Printed Electronic Systems. Spring 2014 Meeting of the Materials Research Society.; San Francisco, CA USA. Date of Talk: 4/21/2013