Multi-wavelength micromachining of silicon and glass by Q-switched short pulsed lasers

Abstract

Laser micromachining of semiconductor materials, silicon wafers glass and quartz are experimentally investigated using the Spectra Physics diode pumped solid state (DPSS) laser. The Q-switched Nd:YVO4 DPSS laser having a fundamental wavelength of 1064 nm with high pulsing frequencies (15 – 300 kHz) and a short pulse duration (10 ns) is used for micromachining. The laser drilling of an array of holes, machining of micro-channels, micro-milling, cutting and dicing of wafers and micro texturing are performed with frequency – doubled (II), - tripled (III), and –quadrupled (IV) harmonic generations (HG). A high resolution optical microscope and optical profiler are used to characterize the microstructures of the various features formed. The laser threshold fluence for the ablation of silicon for different wavelengths is numerically determined.Laser micromachining of semiconductor materials, silicon wafers glass and quartz are experimentally investigated using the Spectra Physics diode pumped solid state (DPSS) laser. The Q-switched Nd:YVO4 DPSS laser having a fundamental wavelength of 1064 nm with high pulsing frequencies (15 – 300 kHz) and a short pulse duration (10 ns) is used for micromachining. The laser drilling of an array of holes, machining of micro-channels, micro-milling, cutting and dicing of wafers and micro texturing are performed with frequency – doubled (II), - tripled (III), and –quadrupled (IV) harmonic generations (HG). A high resolution optical microscope and optical profiler are used to characterize the microstructures of the various features formed. The laser threshold fluence for the ablation of silicon for different wavelengths is numerically determined.