This paper presents an approach of “film separation” and “transfer” to fabricating functional films or devices on polymeric substrates. For either a ferroelectric La-doped Pb(Zr,Ti)O3, PLZT thin film or a ZnO thin film, using laser lift-off (LLO), film separation from the transparent rigid substrate (sapphire or glass) was achieved. The film transfer to a polymeric receptor substrate was obtained by laminating the polymeric substrate on the film stack prior to LLO. The introduction of a sacrificial layer between the film and the substrate mostly resolved concerns to induce damages during LLO. Electrical testing of the films before and after LLO demonstrated the film properties on the original substrate were satisfactorily retained even for the transferred films on the polymeric substrate.

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Zinc oxide ͑ZnO͒ micropatterns were synthesized site-selectively on photocatalytically activated regions of TiO 2 in an aqueous solution of zinc nitrate and dimethylamine-borane at 55°C by an electroless deposition process. The as-deposited ZnO micropatterns showed a polycrystalline wurtzite structure with a thickness of approximately 0.1 m. The ZnO micropatterns emitted ultraviolet light at 380 nm due to the recombination of bound excitons and broad visible-light luminescence ͑500-800 nm͒. Since the first report of ultraviolet by lazer from zinc oxide ͑ZnO͒, 1,2 substantial effort has been devoted to the development of synthetic methodologies for ZnO films. Among the various techniques described in the literature, evaporation and condensation processes are favored for their simplicity and high-quality products, but these gas-phase approaches generally require economically prohibitive temperatures of 800-900°C.3,4 Despite recent metallorganic chemical vapor deposition ͑MOCVD͒ schemes that reduced the deposition temperature to 450°C by using organometallic zinc precursors, 5 the commercial potential of gas-phase grown ZnO films remains constrained by the size and cost of the vapor deposition systems. Thus, a low-temperature, large-scale, and versatile synthetic process is needed before ZnO can have realistic applications in solar energy conversion, 6 light emission, 7 and other promising areas. [8][9][10] Solution approaches to ZnO films are appealing because of their low growth temperatures and good potential for scale-up. Because of this, Izaki et al. developed an electroless deposition ͑ELD͒ method for polycrystalline particulate ZnO films that is based on the reduction of nitrate ions and that uses dimethylamine borane ͑DMAB͒.11,12 By immersing substrates in an aqueous solution maintained at ϳ60°C, crystalline ZnO particulate films were obtained on the Pd catalyst particles attached to the substrates. However, in spite of the importance of the solution approaches to the fabrication of ZnO films, the chemical deposition mechanism of the ZnO film from aqueous solution is controversial, and several mechanisms have been proposed. Izaki et al. explained that the reduction reaction of the nitrate ion plays an important role in ZnO formation from the solution and is driven by the oxidation reaction of DMAB contained in the solution.11,12 It was also proposed that the deposition mechanism of the ZnO film originates from precipitation of Zn͑OH͒ 2 by the reduction of oxygen, 13,14 and participation of superoxide radicals by the reduction of oxygen. 15Selective ELD has recently become very promising for micro-/ nanostructuring a wide range of materials; that is, a method in which metal is electrolessly plated up from a predetermined pattern. In particular, it is proving increasingly useful in semiconductor and packaging technologies. A major requirement prior to performing selective ELD is the catalytic Pd seed ͑the placement and activation of the seed on the surface͒ and its selectivity: the seed must be confined to sp...

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