Low Temperature Solution-Based Fabrications of Metal Oxide Semiconductor Films by Mechanical Sintering

ABSTRACTVarious flexible electronic devices have been intensively studied and developed in this decade. Most of consumers expect to obtain these flexible electronic devices in the next decade. The spread of flexible electronic devices depends on the process costs and material costs. Today prices of materials and energy sources are continuously increasing. Therefore, using of expensive materials and wasteful processes for fabricating electronic devices should be reconsidered. Printing techniques, a representative solution process, are inexpensive and very effective for mass production of electronic devices. We have developed a low-temperature process for fabricating flexible printed patterns of metals and semiconductors by using relatively inexpensive commercial pastes. A characteristic of our process is to utilize mechanical energies for sintering particles contained in pastes. In our process, the precise three-dimensional pressure control brings about the improvement of electrical properties in the printed patterns, the preservation of pattern accuracy and the mechanical durability of the printed patterns. In our experiment, we have already fabricated very low resistivity metal patterns (about 6×10−6Ω·cm) at ca.120°C without using any kinds of nano-particle paste, and also fabricated metal oxide semiconductor patterns.