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The electrical and patterning properties of direct imprinted indium oxide (In2O3) and indium tin oxide (ITO) precursor gel films have been studied. The electrical properties of the imprinted films have also been compared with the electrical properties of non-imprinted films. In2O3 and ITO have almost the same type of solutes in solution but In2O3 shows better patterns than ITO, that is, the addition of tin to In2O3 causes the patterns to degrade because ITO has a lower tan d during viscoelastic measurements than In2O3. In addition, the electrical properties (i.e. Hall mobility and carrier concentration) of In2O3 were affected by the direct imprinting process while the effects were not pronounced for ITO films.

We report on a new fabrication process for thin-film transistors (TFTs) with a new structure and a new operation principle. In this process, both the channel and electrode (source/drain) are formed simultaneously, using the same oxide material, using a single nano-rheology printing (n-RP) process, without any conventional lithography process. N-RP is a direct thermal imprint technique and deforms oxide precursor gel. To reduce the source/drain resistance, the material common to the channel and electrode is conductive indium-tin-oxide (ITO). The gate insulator is made of a ferroelectric material, whose high charge density can deplete the channel of the thin ITO film, which realizes the proposed operation principle. First, we have examined the n-RP conditions required for the channel and source/drain patterning, and found that the patterning properties are strongly affected by the cooling rate before separating the mold. Second, we have fabricated the TFTs as proposed and confirmed their TFT operation.