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Billions of light emitting diodes ͑LEDs͒ are used today in traffic control, automotive headlights, flat panel display technology, mobile devices, back lighting, projection, and general illumination applications. With the dramatic growth in LEDs, manufacturers are looking for technologies to increase production yield and decrease cost. Sapphire wafer singulation into miniature dies is one of the critical steps used in blue LED manufacturing. Typical dicing techniques used in wafer singulation process include laser dicing, laser scribing and breaking, mechanical scribing and breaking, and diamond blade sawing. In recent years, laser scribing and breaking has proven to be very efficient for volume LED manufacturing. In this paper, we have characterized the effect of 355 nm Q-switched diode-pumped solid-state ͑DPSS͒ laser parameters such as fluence, pulse width, and repetition rate on laser scribing process by measuring sapphire wafer cutting depth and scribe kerf width. Furthermore, we have also explored the techniques to increase process efficiency while maintaining quality of scribes using different laser sources.

In the manufacture of thin‐film photovoltaic (TFPV) solar panels, Q‐switched diode‐pumped solid‐state (DPSS) lasers are routinely used for “laser scribing” – the selective removal of thin‐film materials. These lasers are available at various wavelengths (266–1064nm), output powers (0.5–34W), repetition rates (up to 500KHz) and pulse durations (<10 to greater than 100ns).Developing the ideal laser scribe process – that is, one that removes only the desired material leaving the adjacent material unaffected – can be a challenge. In a non‐ideal scribe process, not only can there be leftover material, but also high ridges can form along the scribe line. Additionally, the supportive glass substrate can develop micro‐cracks that can then cause lift‐off of the thin‐film material. Because these unwanted ridges and burrs interfere with subsequent thin‐film layers, these non‐uniformities can lead to electrical shorts that reduce TFPV efficiencies and yields.This article addresses the various ways in which pulse duration affects the laser scribe process – specifically thin‐film removal thresholds, scribe quality and substrate quality. It is shown that laser systems with shorter pulse durations will generally result in a laser scribe process that has lower material removal thresholds, cleaner scribes and minimal damage to glass substrates, ultimately leading to higher yields and lower overall manufacturing costs of TFPV panels.

Laser scribing of various thin film materials is a key process in manufacturing of thin film photovoltaic (PV) panels. In recent years, PV industry has adopted the use of high-power nanosecond-pulse diode pumped solid state (DPSS) Q-switch lasers to increase precision and throughput of scribe processes. A major push for the use of lasers is made in order to increase the quality of scribes and hence the efficiency of a solar cell while reducing fabrication costs. This paper focuses on identifying advantages of using a Gaussian shaped laser beam from a DPSS Q-switch laser for thin film scribe processes. In particular, scribing with a Gaussian laser beam and a flattop shaped laser beam has been evaluated and compared. From a laser scribing system design perspective, the effect of beam intensity distribution on the process depth of focus has been characterized. In addition, scribing with a high quality low M 2 Gaussian beam from a DPSS q-switch laser and a beam from a high M 2 fiber laser has been compared. Again from a laser scribing design perspective, the effect of each laser on process depth of focus has been characterized.

Diode pumped solid state (DPSS) Q-switched nanosecond pulsed lasers are becoming the laser of choice for a wide variety of processes in printed circuit board (PCB) manufacturing. Lasers are being used today in PCB manufacturing for via drilling, depaneling, profiling (cutting), laser direct imaging (LDI), repair, trimming, marking, skiving and other processes. The majority of these processes are practiced today using a 10.6 μm CO 2 or 355nm ultraviolet (UV) laser. In this study we have investigated the use of our new generation of Qswitched DPSS nanosecond pulsed 532 nm green laser for PCB processing. We demonstrate this green laser is a good candidate for processing some thin PCBs.

Majority of high volume laser manufacturing processes require high throughput, improved accuracy, and minimal thermal damage to the target material. Diode pumped solid state (DPSS) Qswitched nanosecond pulsed lasers are routinely being used today in the manufacture of semiconductor, microelectronics and solar cells. They offer low noise, high stability, and reliability required for a robust manufacturing process. Over the past few years the energy available per pulse and the repetition frequency of such lasers have increased dramatically. In this paper we describe three different fluence management techniques to effectively use the high energy and repetition frequency available from a short pulse width 355 nm DPSS Q-switched laser to maximize the material removal rate and maintain the highest possible quality. Experimental data for ceramic scribing is presented to demonstrate the advantages offered by the proposed techniques.

Billions of LEDs are used today in traffic control, automotive headlights, flat panel display technology, mobile devices, back lighting, projection and general illumination applications. With the dramatic growth in LEDs, manufacturers are looking for technologies to increase production yield and decrease cost. Sapphire wafer singulation into miniature dies is one of the critical steps used in blue/green LED manufacturing. Typical dicing techniques used in wafer singulation process include laser dicing, laser scribing and breaking, mechanical scribing and breaking, and diamond blade sawing. In recent years, laser scribing and breaking has proven to be very efficient for volume LED manufacturing. In this paper we have characterized the effect of 355nm Qswitched DPSS laser parameters such as fluence, pulse width and repetition rate on laser scribing process by measuring sapphire wafer cutting depth and scribe kerf width. Furthermore we have also explored the techniques to increase process efficiency while maintaining quality of scribes using different laser sources.