Research into the process, materials and tool interaction for large area flexible electronics with micron sized features

By taking the advantage of the flexible nature of flexible substrates, roll-to-roll (R2R) flexible electronics manufacturing will eventually lead to continuous production of high quality and flexible thin film devices with a significant cost reduction. In this work, research has been conducted into the interaction of tooling, material and process for large area flexible electronics with micron sized features.;Part one presents the study of precision overlay alignment of micron sized features on unsupported and R2R processed plastic. Azores R2R photolithography tool with dependent materials and processes has been applied to establish the fabrication, registration and overlay on unsupported plastic in pieces and carried by a web. Enabling the use of unsupported plastic film is the first step in understanding the R2R process. Test verniers with up to 0.1 micron measurement precision were used to read the overlay offsets. Micro-sized features with one micron overlay accuracy have been achieved on photoresist coated unsupported 5 mil thick Dupont MelinexRTM ST507 polyethylene terephthalate (PET) substrate. Based on experimental results, a vector model is initially designed to investigate and map the substrate deformation and overlay alignment in R2R photolithography process. The vector model quantifies the significance of elastic deformation caused distortion offsets in the overlay process on R2R based substrates.;Part two presents the fabrication and reliability study of flexible chemical sensors with nanoparticle-structured sensing materials. The substrates of flexible chemical sensor with micron-sized features are fabricated in this work. The mechanical reliability of the flexible chemical sensors is initially investigated to test the functionality of the sensors under different working environments. The Accelerate Thermal Cycling (ATC) test, the Deep Thermal Storage (DTS) test and the Immersion test are conducted on the flexible nanoparticle coated sensors.