Micromachining compatible metal patterning technique using localized decomposition of an organometallic compound by laser irradiation

Abstract

Spin coated palladium acetate film was decomposed locally using argon ion laser irradiation and palladium thin film with a line pattern was formed. We studied the effects of the process parameters, such as laser power density and scan rate, on line pattern features and the basic characteristics of the formed palladium thin film. The film had a fine polycrystalline structure with a grain size of up to 100 nm, and high chemical purity, resulting in a low electrical resistivity of the order of cm. The formed line patterns had a smooth surface and flat features. Their thickness was 12% of that of the coated palladium acetate film. The width of the formed palladium line patterns was 100-200% of the spot size of the laser beam, depending on irradiation conditions, due to thermal conduction. This metal pattern deposition technique is not only very simple and flexible, but is also compatible with micromachining processes, since it is a maskless process and is easy to apply to three dimensional structures.

Self-Assembly of Metallic Nanowires from Aqueous Solution

“…Soaking an array for 10 min in a reducing aqueous environment (25 gL -1 sodium citrate, 25 gL -1 85% lactic acid solution, and 2.5 gL -1 dimethylamine borane, pH 7.4) or annealing it for 2 h in a vacuum at 400 °C gave no obvious change in electrical resistance. Because palladium acetate reacts rapidly with a reducing agent 2,3 and decomposes at 220 °C, 21 the data prove that the wires were made largely, if not exclusively, of palladium. It remains to be determined whether our approach will be suitable for other metals.…”

<title>Laser fabrication and assembly processes for MEMS</title>

“…Various other laser-assisted deposition processes have been reported, including processes based on: deposition from spincoated precursors [30], transfer of material from a carrier ribbon to an adjacent substrate [31], and deposition from aerosols [32]. All of these processes are potentially useful for direct write in MEMS applications, although they are not as flexible as LCVD in terms of 3D processing.…”