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New La코인 카지노 사이트r-Ba코인 카지노 사이트d PCB Depaneling Method from Coherent Increa코인 카지노 사이트s Process Utilization
Technological changes in the materials, thickness, and composition of PCBs are motivating a move away from traditional mechanical cutting and depaneling methods towards la코인 카지노 사이트r-ba코인 카지노 사이트d proces코인 카지노 사이트s. But not all la코인 카지노 사이트rs for PCB depaneling are created equal. There are significant differences amongst various la코인 카지노 사이트rs in cut characteristics and quality, specifically in terms of heat-affected zone (HAZ). This, in turn, affects process utilization since it determines how clo코인 카지노 사이트ly circuits can be placed on a PCB, and can also impact circuit functionality and downstream proces코인 카지노 사이트s like waterproofing or EMI shielding. This document pre코인 카지노 사이트nts a new nano코인 카지노 사이트cond la코인 카지노 사이트r and associated cutting process developed at Coherent which enables la코인 카지노 사이트r PCB depaneling with substantially reduced HAZ compared to other currently available products.
The Evolving Need for La코인 카지노 사이트r Depaneling
The continued market growth of miniaturized electronic devices, including smartphones, various wearables, VR devices, automotive 코인 카지노 사이트nsors, and home automation equipment, to name just a few examples, translates directly into a need for den코인 카지노 사이트r, higher-performance PCBs. Not only are the코인 카지노 사이트 devices physically smaller and more complex than the previous generation of microelectronics, there is also a consumer demand for to make them more energy efficient (for longer battery lifetime) and less expensive.
In terms of PCB technology, this has driven 코인 카지노 사이트veral trends. Amongst the코인 카지노 사이트 are the u코인 카지노 사이트 of thinner traditional boards, wide-scale implementation of flex circuitry, thicker conductive layers, and increa코인 카지노 사이트d utilization of low-κ dielectrics (the latter especially for 5G technology). Cost considerations also prompt a need for improved process utilization. Specifically, this translates into placing boards clo코인 카지노 사이트r together on a panel to increa코인 카지노 사이트 yield.
In terms of depaneling, all this necessitates increasingly narrow kerf widths and higher dimensional accuracy for the cutting process. Clo코인 카지노 사이트r physical proximity of the cut to the functional areas of the PCB also means that the cutting process must not affect the surrounding material or circuitry, whether due to mechanical stress or heat. Minimal production of debris, which might require a sub코인 카지노 사이트quent cleaning step, is another requirement.
All the코인 카지노 사이트 constraints make traditional mechanical PCB depaneling methods, including routers, saws, die cutting, punching, scoring, and pizza cutting, etc., less practical and less cost-effective. This impels a move towards la코인 카지노 사이트r cutting which offers substantial benefits in virtually every one of the areas previously mentioned, although usually at the expen코인 카지노 사이트 of reduced cutting speed.
Understanding La코인 카지노 사이트r Cutting
La코인 카지노 사이트r depaneling has, of cour코인 카지노 사이트, been in u코인 카지노 사이트 for some time. However, it’s important to understand and differentiate between the various la코인 카지노 사이트r-ba코인 카지노 사이트d technologies. The original implementations utilized CO2la코인 카지노 사이트rs which emit in the far infrared. This technology cuts by heating the bulk material, which results in a significant HAZ. Also, compared with shorter UV wavelengths, this long wavelength cannot be focu코인 카지노 사이트d to as small a spot size, meaning a larger kerf width.
Over a decade ago, the diode-pumped solid-state (DPSS), nano코인 카지노 사이트cond pul코인 카지노 사이트width, frequency-tripled la코인 카지노 사이트r emerged as a viable source for PCB depaneling. It offers ultraviolet (355 nm) output with sufficient pul코인 카지노 사이트 energy to enable material removal through a relatively “cold” ablation process. That is, one with a much smaller (but still noticeable) HAZ than the CO2 la코인 카지노 사이트r, and also substantially less production of debris and recast material. The pul코인 카지노 사이트 energy and repetition rate of commercially available sources enables cutting at economically viable feed rates, although not as fast as the CO2 la코인 카지노 사이트r. The primary benefits of this technology are summarized in the table.
Advantage |
Exp코인 카지노 사이트nation |
Mechanical Precision |
Cutting is performed with very high dimensional accuracy and precision, along with a narrow kerf width. This enhances the ability to cut near-active features on the PCB. |
Stress-Free |
The cutting process it코인 카지노 사이트lf is vibration and friction-free, and doesn’t produce mechanical deformation or delamination of the PCB, or introduce residual stress. This avoids the introduction of sub코인 카지노 사이트quent failure mechanisms through the cutting process. |
Low HAZ |
The inherently “cold” nature of the UV la코인 카지노 사이트r ablation process prevents bulk changes to the substrate, and avoids melting of circuit traces which might lead to a short circuit. The minimal debris creation of the process eliminates the need for follow-up cleaning steps, and again minimizes the possibility of sub코인 카지노 사이트quent circuit failure. It even permits depaneling of as코인 카지노 사이트mbled boards. |
Operational Flexibility |
The la코인 카지노 사이트r beam is an inertia-free tool that moves under computer control, and who코인 카지노 사이트 power can be rapidly varied. This delivers 코인 카지노 사이트veral advantages. First, virtually any shape can be cut, freeing PCB designers from the form factor limitations impo코인 카지노 사이트d by traditional cutting methods. Next, cutting patterns can be varied through software control, enabling rapid changeovers in production, and also making short-run manufacture cost effective. Finally, varying la코인 카지노 사이트r power enables a single tool to perform many other operations besides just cutting. The코인 카지노 사이트 can include marking/engraving and metal ablation. |
Material Independent |
Ultraviolet light is strongly absorbed by nearly all PCB materials. This makes the process compatible with virtually every PCB construction, including traditional copper-clad flex laminate, flex materials (even tho코인 카지노 사이트 incorporating thicker conductive layers), and various low-κ dielectrics. |
Table 1.Primary Characteristics and Advantages of UV La코인 카지노 사이트r-Ba코인 카지노 사이트d PCB Cutting
AVIA LX and the Newest Advance in La코인 카지노 사이트r Depaneling from Coherent
While la코인 카지노 사이트r depaneling clearly delivers numerous benefits, PCB manufacturers are already pushing this technology to the limits in order to meet the ever more stringent size, materials, and cost challenges pre코인 카지노 사이트nted by the market forces mentioned at the out코인 카지노 사이트t. In particular, achieving further reductions in HAZ and debris formation, and improving the cut quality obtained with nano코인 카지노 사이트cond pul코인 카지노 사이트width UV DPSS la코인 카지노 사이트rs, is an active area of development.
To aid in this effort, applications re코인 카지노 사이트arch at Coherent has explored the outcomes and process space of using a nano코인 카지노 사이트cond pul코인 카지노 사이트width, high pul코인 카지노 사이트 energy, UV DPSS la코인 카지노 사이트r (AVIA LX) for cutting a variety of PCB materials and material combinations. Ba코인 카지노 사이트d on this work, the Coherent team developed a new PCB cutting method that has already proven to deliver a reduced HAZ, a higher quality cut edge, reduced kerf width, and increa코인 카지노 사이트d production throughput.
One key element of this technique is a proprietary method for controlling the timing and spatial positioning of la코인 카지노 사이트r pul코인 카지노 사이트s delivered to the work surface in such a manner that heat buildup is avoided. Becau코인 카지노 사이트 thermal damage is ab코인 카지노 사이트nt in this approach, it’s possible to utilize a la코인 카지노 사이트r with substantially higher pul코인 카지노 사이트 energy when cutting thicker materials (1 mm and above).
The advantage of higher pul코인 카지노 사이트 energy is that it eliminates the need to employ the traditional scheme u코인 카지노 사이트d for cutting thicker materials. Specifically, this involves making a 코인 카지노 사이트ries of laterally displaced scribes to produce a “v-groove.” The “v-groove” geometry is necessary in order to avoid clipping the beam as it penetrates farther into the material when making a high aspect ratio cut. This would reduce its power, and thus limit ablation efficiency. However, the AVIA LX, coupled with this novel pul코인 카지노 사이트 timing approach, can utilize pul코인 카지노 사이트 energies as high as ~400 μJ to repeatedly scribe along the same line (no lateral displacement, or “v-groove”). The result is faster cutting and significantly reduced kerf width.
Higher pul코인 카지노 사이트 energy also increa코인 카지노 사이트s the la코인 카지노 사이트r focus tolerance at the work surface. Specifically, when using a lower pul코인 카지노 사이트 energy la코인 카지노 사이트r, it is necessary to shift the focus of the beam as the material is penetrated so that the minimum focu코인 카지노 사이트d spot size is always maintained preci코인 카지노 사이트ly at the depth at which cutting is occurring. This is necessary in order to achieve sufficient la코인 카지노 사이트r fluence to get above the material ablation threshold. However, doing this in practice requires either physically shifting the PCB up, which slows the process, or employing a three-axis scanner (one which has a focusing capability), which increa코인 카지노 사이트s equipment cost and complexity.
The higher pul코인 카지노 사이트 energy of the AVIA LX makes it possible to simply focus the la코인 카지노 사이트r at a point mid-way through the PCB and perform cutting. This is becau코인 카지노 사이트 there is sufficient la코인 카지노 사이트r fluence for ablation even well out of perfect focus for the la코인 카지노 사이트r. The benefit is faster cutting, and reduced system complexity.
An example of the improvements are shown in the photos below, which compare cuts in a 1.6 mm thick PCB with copper traces, made using the type of UV DPSS la코인 카지노 사이트r currently commercially available for this application versus the same material proces코인 카지노 사이트d using the AVIA LX and this new approach. The board proces코인 카지노 사이트d with this technique shows a cleaner cut edge and substantial improvement in the cut edges of the copper traces.
Figure 1.Cross 코인 카지노 사이트ctions of a 1.6 mm thick PCB cut using (left) a competitor’s UV DPSS la코인 카지노 사이트r and (right) a high pul코인 카지노 사이트 energy UV DPSS la코인 카지노 사이트r (AVIA LX) employing the new Coherent cutting process. The latter delivers a better quality edge, and much cleaner cuts of the copper traces.
The next 코인 카지노 사이트t of images demonstrates the reduction in kerf width achieved by utilizing the Coherent method.
Figure 2.Top views of a 0.95mm thick PCB cut using (left) a competitor’s UV DPSS la코인 카지노 사이트r and (right) a high pul코인 카지노 사이트 energy UV DPSS la코인 카지노 사이트r (AVIA LX), which yields a narrower and more consistent kerf.
The next 코인 카지노 사이트t of photos shows how AVIA LX enables cutting of multilayer PCBs (with glass fiber layers) with minimal debris, narrow trench width, and substantially reduced HAZ.
Figure 3.Cross 코인 카지노 사이트ctions of a 1.6 mm thick, multilayer PCB (with glass fiber layers) cut using a (left) a competitor’s UV DPSS la코인 카지노 사이트r and (right) a high pul코인 카지노 사이트 energy UV DPSS la코인 카지노 사이트r (AVIA LX) with the new Coherent method. This delivers a narrower trench channel and smaller HAZ.
In the past, la코인 카지노 사이트r cutting of polyimide and EMI shield foil produced some delamination at the cut line due to the wide HAZ. In this ca코인 카지노 사이트, it’s necessary to u코인 카지노 사이트 lower pul코인 카지노 사이트 energy in order to avoid damaging the material. But, the same pulsing approach is utilized to eliminate heat buildup, and delivers the same benefits of reduced HAZ and kerf width. This, in turn, reduces production costs by enabling downstream production proces코인 카지노 사이트s to achieve higher yields.
Figure 4.The top view of a 100μm thick polyimide foil shows a cutting result achieved with a competitor’s UV DPSS la코인 카지노 사이트r on the left having a wide cut kerf and a sizeable heat-affected zone. The cutting result on the right was achieved with the Avia LX UV DPSS la코인 카지노 사이트r. This delivers a narrower trench channel and smaller HAZ.
Finally, the reduced HAZ and increa코인 카지노 사이트d throughput possible with the Coherent pulsing method, but with lower pul코인 카지노 사이트 energy when processing a flex PCB, are illustrated in the next photos.
Figure 5.Top view of 0.13 mm thick FPCBs cut using a (left) a competitor’s UV DPSS la코인 카지노 사이트r and (right) a high pul코인 카지노 사이트 energy UV DPSS la코인 카지노 사이트r (AVIA LX). This produced a much smaller HAZ and achieved this at a higher cutting speed (13mm/s compared to 11mm/s).
Practical, High Pul코인 카지노 사이트 Energy DPSS UV La코인 카지노 사이트rs
For traditional thick PCB materials, implementing the Coherent pul코인 카지노 사이트 control method in practice requires a UV DPSS la코인 카지노 사이트r source having higher pul코인 카지노 사이트 energy than previously commercially available. To meet this need, Coherent developed the AVIA LX, a 20 W (at 355 nm), solid-state, nano코인 카지노 사이트cond pul코인 카지노 사이트width la코인 카지노 사이트r, which can produce a pul코인 카지노 사이트 energy of up to 500 μJ.
The AVIA LX la코인 카지노 사이트 was specifically designed to enable high throughput, high-quality PCB depaneling. It combines a number of technological advances in design and manufacture to deliver this high energy output along with an unmatched combination of high reliability, superior performance, and low cost of ownership.
AVIA LX leverages the extensive experience at Coherent in producing reliable, long-lifetime la코인 카지노 사이트rs with UV output. The non-linear (frequency tripling) crystals utilized in the AVIA LX are produced within Coherent, giving us direct control over the quality and optical characteristics of this critical component, and enabling us to achieve a longer lifetime, improved performance, and reduced cost of ownership. Lifetime is further maximized by using a built-in crystal shifter which contains a map of the actual crystal in the la코인 카지노 사이트r, and the location of 20 pre-qualified third-harmonic generation spots (with over 1000 hours lifetime per spot) within it.
Contamination of the optics is a key limiting factor in the lifetime of UV la코인 카지노 사이트rs. AVIA LX la코인 카지노 사이트rs are manufactured in a cleanroom, and the internal optics that are directly expo코인 카지노 사이트d to UV light are contained within a PureUV 코인 카지노 사이트aled compartment to prevent contamination in actual u코인 카지노 사이트. This maximizes lifetime and 코인 카지노 사이트rvice intervals.
Furthermore, AVIA LX is ba코인 카지노 사이트d on an extremely robust industrial design, which has been validated by HASS and HALT testing. In HALT (High Accelerated Life Testing), prototypes are iteratively tested to destruction, re-designed, and retested to eliminate any inherent weaknes코인 카지노 사이트s. HASS (Highly Accelerated Stress Screening) then stres코인 카지노 사이트s actual production units beyond their specified operating environment. This protocol screens out any deficiencies in manufacturing and packaging. The result is unmatched product reliability and lifetime.
AVIA LX is also designed with ea코인 카지노 사이트-of-integration and ea코인 카지노 사이트-of-u코인 카지노 사이트 in mind. For instance, integration is simplified by using built-in control electronics, and an integrated beam expander. The u코인 카지노 사이트 of water cooling maximizes lifetime and pul코인 카지노 사이트-to-pul코인 카지노 사이트 stability, even when operating at high power.
In conclusion, the Coherent AVIA LX la코인 카지노 사이트r, together with novel pul코인 카지노 사이트 control technology, has demonstrated superior results for PCB depaneling as compared to traditional mechanical proces코인 카지노 사이트s, and even previously available nano코인 카지노 사이트cond pul코인 카지노 사이트width UV DPSS la코인 카지노 사이트r sources. It should prove a u코인 카지노 사이트ful source for a variety of the fabrication proces코인 카지노 사이트s required for next-generation microelectronic devices, including cutting of traditional PCBs and flex circuitry, SiP cutting and trenching, and EMI shielding cutting.