| dc.description.abstract | Quartz is a single-crystal silicon dioxide (SiO2) known for its piezoelectric ef-fects and ability to provide stable frequencies, making it essential for frequency os-cillation components. With ongoing technological advancements and the increasing demand for electronic and optoelectronic devices, the need for frequency oscillation components and their materials is constantly rising. As electronic products continue to shrink in size, components must be miniaturized accordingly. To meet the market demand for quartz wafers, reducing quality and material loss during the cutting pro-cess while improving cutting speed are crucial goals.
Single-crystalline quartz is a transparent, hard, and brittle material. Traditional dicing methods primarily use diamond tools, which can cause a higher proportion of damage to quartz wafers and require wider cutting kerfs, increasing costs. Therefore, non-contact laser processing is a suitable method for cutting quartz wafers. This study investigates laser stealth dicing of quartz wafers with thicknesses of 65 μm and 80 μm using a laser source with a wavelength of 515 nm and a pulse width of 300 fs. Initially, three laser cutting strategies from the literature were attempted: conventional stealth dicing, one-step stealth dicing, and internal modification com-bined with surface ablation cutting methods. By analyzing the different cutting strategies and comparing the results, a wavy scanning path was proposed and opti-mized, the result could achieve a surface roughness of less than 1 μm at an optimal dicing speed of 2 mm/s.
Furthermore, to enable immediate wafer separation after laser cutting, this study employed burst mode in conjunction with the newly designed wavy laser scanning path as a second stage of laser processing, resulting in a two-stage laser dicing strategy. First, internal modification of the quartz wafer was performed using pulse mode along the wavy scanning path, creating a relatively weakened channel. Next, burst mode was employed for a second laser scan at selected local positions along this channel, generating cracks within the material that facilitated wafer sepa-ration along the pre-modified channel without needing external force.
The results showed that this fully laser-based quartz wafer dicing method could achieve a surface roughness of less than 1 μm and did not require external force for wafer separation. | en_US |