• Korean Journal of Materials Research
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• v.18 no.5
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• pp.247-252
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• 2008

A laser glass cutting system using a femto-second laser was evaluated for Flat Panel Display (FPD) glass. A theoretical analysis of the ablation threshold and depth is described using an explicit analytic form. Experiments for clean and deep grooves were performed using a 3W femto-second laser, and the relationships between the input energy and the scribing depth as well as the threshold energy are presented. Mechanical breaking after the scribing process was carried out and the results are compared with a theoretical method. It was found that a two-sided LCD panel glass can be cut clearly using the laser cutting method. The methodology was found to be very effective as a mass-production cutting system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1319-1324
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• 2007

Accurately controlling the shape of the read/write head structure is critical in the performance of a modem hard disk drive. The sliders investigated are composed of alumina and titanium carbide(AITiC) and act as an air bearing when passing over the disks. Controlling the curvature of the slider is of primary importance. A laser scribing system that produces curvature by inducing residual stress into the slider can be utilized. Predicting the curvature created by a pattern of scribes is of great importance to increase the control over the sliders' shape. The force system that produces stresses similar to the laser scribing is applied to the finite element analysis model. The curvatures created by the force system are calibrated to experimental measurements.

• Proceedings of the Korean Society of Laser Processing Conference
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• 2005.06a
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• pp.15-20
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• 2005

• Proceedings of the Korean Society of Laser Processing Conference
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• 1999.11a
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• pp.33-35
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• 1999

• Korean Journal of Materials Research
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• v.27 no.5
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• pp.248-254
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• 2017

In the present work, graphene powder was synthesized by laser scribing method. The resultant flexible light-scribed graphene is very appropriate for use in micro-supercapacitors. The effect of the laser scribing process in reducing graphene oxide (GO) was investigated. GO was synthesized using a chemical mixture of GO solution; then, it was coated onto a LightScribe DVD disk and laser scribed to reduce GO and create laser-scribed graphene (LSG). The CV curves of pristine rGO at various scan rates showed that the ultimate product possesses the ability to store energy at the supercapacitor level. Charge-discharge curves of pristine rGO at two different current densities indicated that the specific capacitance ($C_m$) increases due to the reduction of the discharge current density. Finally, the long-term charge-discharge stability of the LSG was plotted and indicates that the specific capacitance decreases very slightly from its primary capacitance of ${\sim}10F\;cm^{-3}$ and that the cyclic stability is favorable over 1000 cycles.

• Journal of the Korean Magnetics Society
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• v.15 no.6
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• pp.320-324
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• 2005

The core loss of $3\%$ SiFe is strongly dependent on silicon content, impurities, permeability, and domain structure of the SiFe. Domain refining has been proved to be very good method for reduction of core loss in high permeability grain oriented SiFe, and laser scribing is well-blown as an effective and industrially important method of domain refinement. In this work, magnetic domain refinement has been carried out by using a pulsed Nd : YAG laser, and the core losses have been measured and analyzed to and optimal parameters of the laser treatment. The laser hem was focused with a spot size of $100{\mu}m$ and pulse energy of 10${\~}$35mJ and the lines were scribed with a period of ${\~}$5mm. The core loss was improved up to $17\%$ with 30 ns-Nd : YAG laser beam in $3\%$ SiFe.

• Current Photovoltaic Research
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• v.12 no.2
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• pp.37-40
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• 2024

One of the current innovation trends in the solar industry is the increase in the size of silicon wafers. As the wafer size increases, the series resistance of the module rises, highlighting the need for research on methods for cutting and bonding solar cells. Among these, the Infrared (IR) laser scribing technique has been extensively researched. However, there is still insufficient optimization research regarding the thermal damage caused by lasers on the Transparent Conductive Oxide (TCO) layer of Heterojunction (HJT) solar cells. Therefore, in this study, we systematically varied conditions such as IR laser scribing speed, frequency, power, and the number of scribes to investigate their impact on the performance of cut cells under each condition. Additionally, we conducted a comparative analysis of thermal damage effects on the TCO layer based on varying scribing depths.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.11a
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• pp.106-106
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• 1998

• Proceedings of the Korean Vacuum Society Conference
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• 2008.08a
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• pp.330-330
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• 2008

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.224-225
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• 2000

Transparent and hard materials such as sapphire are used for many industrial applications as optical windows, hard materials on mechanical contact against abrasion, and substrate materials for opto-electronic semiconductor devices such as blue LED and blue LD etc. The materials should be cut along the proper shapes possible to be used for each application. In case of blue LED, the blue LED wafer should be cut to thousands of blue LED pieces at the final stage of the manufacturing process. The process of cutting the wafer is usually divided into two steps. The wafer is scribed along the proper shapes in the first step. It is inserted between transparent flexible sheets for easy handling. And then, it is broken and split in the next step. Harder materials such as diamonds are usually used to scribe the wafer, while it has a problem of low depth of scribing and abrasion of the harder material itself. The low depth of scribing can induce failure in breaking the wafer along the scribed line. It was also known that the expensive diamond tip should be replaced frequently for the abrasion. (omitted)