| Summary: | We present a novel, laser-based microstructuring technique for the etching and deposition of solid materials. This technique, which we call laser-induced solid etching (LISE), utilises the absorption of femtosecond duration laser pulses in a constrained metal film between two bulk substrates, at least one of which is transparent to the laser wavelength. The very rapid pressure increase in the metal film following irradiation is believed to initiate crack-propagation in one or other of the bulk substrates. By spatially shaping the laser beam, the cracking process can be controlled to etch solid chunks of material from the substrates. Using LISE we have etched smooth, micron-scale pits and trenches in silicon and silica. The results will be compared to etched features produced using conventional techniques. A unique feature of LISE is that the material etched from the bulk substrate is removed as a single solid piece and is not shattered, melted, or vaporised by the process. Hence, the etched material can be collected on the other bulk substrate used in the process. In this way, we have deposited micron-scale dots and lines of silica onto silicon and vice-versa. The deposited structures obtained using LISE compare well with those obtained with conventional laser forward transfer techniques. Minimal evidence of melting during the process has been observed, suggesting that LISE may be a useful technique for the forward transfer direct-write of intact solid materials
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