Ultraprecision laser micromachining has excited vivid attention in various industrial fields owing to the rapid progress in laser design capable of emitting powerful pulses with durations of less than 1 ps. Material damage achieved on the targets is determined to a major extent by the heat affected zone (HAZ). Femtosecond laser treatment leads to about one order of magnitude smaller HAZ's compared to nanosecond laser machining. The threshold fluences for ablation decrease significantly and the structuring quality can be enhanced by use of ultrashort laser pulses. This behaviour was investigated for a wide range of different materials, like metals, semiconductors, dielectrics and composites. Especially results of laser ablation of semiconductors with pulses of 300 fs duration at 612-620 nm wavelength and a repetition rate of a few Hertz are reviewed. Further on laser-induced deposition of narrow transition metal traces was studied on cathodically biased p-type single crystalline silicon in aqueous solutions. The metal deposition is characterized by instantaneous 2-D needle growth, respectively, and subsequent 3-D growth followed by coalescence of hemispheres. The mechanism as well as applications will be discussed.
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