Technical Library | 2023-11-09 08:53:45.0
Crafting an Efficient SMT Conformal Coating Line for Double-Sided PCBA In the intricate realm of electronics manufacturing, selecting the ideal SMT conformal coating line can seem like a challenging quest. The pursuit of a solution that seamlessly integrates efficiency, reliability, and performance is the ultimate goal. In this article, we embark on a journey to unravel the secrets of a standard SMT conformal coating line, using a captivating visual guide as our compass. The Symphony Of Components In An SMT Conformal Coating Line Picture a finely orchestrated symphony, with each instrument playing a unique role in this PCB coating process. The star performers in this lineup include: Transfer Conveyor: These act as the stage where the PCB's journey begins. Think of them as the entry and exit points for your precious boards, allowing a smooth, choreographed dance through the line. 1st Coating Machine: As the first movement in this musical journey, this machine, partnered with the initial curing station, lays down the foundation – applying adhesive to one side of the PCB. Inspection Conveyor: After the initial curing, our inspectors take center stage, using these transfer stations to carefully evaluate the coating's quality. 1st Curing Oven: This is where the magic happens. The first curing oven solidifies the adhesive applied in the previous act, setting the tone for a flawless performance. Flipper Machine: The flipper machine takes the spotlight, gracefully turning the PCB to reveal its other side, ensuring both faces receive their share of adhesion. 2nd Coating Machine: With a newfound perspective, the second coating machine takes the stage, applying adhesive to the reverse side of the PCB. 2nd Curing Oven: The grand finale! The second curing oven brings our symphony to a breathtaking close, solidifying the adhesive applied in the second act, creating a harmonious, dual-sided masterpiece. Efficiency Meets Dual-Side Coating This SMT conformal coating line is like a well-choreographed ballet that requires at least two dancers. One stands at the front, carefully loading PCBs onto the stage, guiding them through the first act. After the flip, the second dancer carries them through the second act, with both sides perfectly coated, ensuring a flawless performance for applications requiring dual-sided adhesion. UV Curing Oven For Illuminating Results For applications that embrace UV-curable adhesives, our line includes UV curing ovens, adding a layer of brilliance to the process and ensuring an efficient solidification of adhesives. Transfer Stations With A Touch Of Magic Within this symphony, the transfer stations wear a touch of magic – the second and fourth stations feature enchanting blue glass covers illuminated by embedded LED lights. These stations offer operators a clear view of the adhesive quality, allowing for meticulous inspections. The blue glass covers also act as protective shields, guarding freshly coated PCBs from the ever-present dust fairies. Certified Excellence: European Standards And CE Certification Ensuring that our performance meets the highest standards, our entire ensemble adheres to stringent European safety standards and proudly boasts CE certification, a testament to compliance with safety, health, and environmental protection requirements. A Variety Of Coating Machines For Your Unique Needs Our lineup doesn't just feature one star, but an ensemble of coating machines, including models like I.C.T-T550, I.C.T-T550U, I.C.T-T600, and I.C.T-T650. For an encore performance with detailed specifications of each model, please refer to our dedicated article. Additionally, for a captivating exploration of the right coating valve for your adhesive, please visit our comprehensive guide. Single-Sided PCB Coating For those who prefer a single board, our dedicated article on single-sided PCB coating is a spotlight on this specialized process. In the dynamic world of electronics manufacturing, our SMT conformal coating line stands as a versatile and reliable performance. With dual-sided coating capabilities, adherence to European safety standards, and CE certification, we offer a comprehensive platform for your coating needs. Join us in this symphony and explore our range of coating machines and accessories to enhance your conformal coating process. It's a performance that promises to leave you in awe!
Technical Library | 2012-12-26 20:18:50.0
①Single side The basic flexible printed circuit board is used of substrate of single side pcb materials and coated coverlay after finishing printed. ②Double sided That is made of substrates of double sided printed circuit board with double surface coated coverlays after finishing printed. ③Single copper foil with double coverlays Single copper foil coated different coverlays with double surface after finishing printed. ④Air gap Laminating two single printed circuit board together with no glue and bare design to meet high flexibility requirements. ⑤Multilayer That is designed for three and above circuit layers by laminating single side printed circuit board or double sided printed circuit board. ⑥COF IC chips and electronic components are installed on the flexible circuit board directly. ⑦Rigid-Flexible PCB Combined to rigid PCB with supporting and flexible PCB with high flexibility.
Technical Library | 2015-03-19 20:33:34.0
Silicon is arguably the best electronic material, but it is not a good optoelectronic material. By employing first-principles calculations and the cluster-expansion approach, we discover that hydrogenated bilayer silicene (BS) shows promising potential as a new kind of optoelectronic material. Most significantly, hydrogenation converts the intrinsic BS, a strongly indirect semiconductor, into a direct-gap semiconductor with a widely tunable band gap. At low hydrogen concentrations, four ground states of single- and double sided hydrogenated BS are characterized by dipole-allowed direct (or quasidirect) band gaps in the desirable range from 1 to 1.5 eV, suitable for solar applications. At high hydrogen concentrations, three well-ordered double-sided hydrogenated BS structures exhibit direct (or quasidirect) band gaps in the color range of red, green, and blue, affording white light-emitting diodes. Our findings open opportunities to search for new silicon-based light-absorption and light-emitting materials for earth-abundant, high efficiency, optoelectronic applications.Originally published by the American Physical Society
Technical Library | 2016-08-04 10:34:35.0
With the onset of 1900’s, the novelty of printed circuits boards got started with a profound concept of constructing an electrical path on an isolated surface of a board. The initial trend of printed circuit board got into a vain to develop and upgrade the radios and gramophones. Gradually the notion of ‘Through Hole Technique’ came into picture to produce a double sided PCB. In mid 1990’s the idea of auto assembly process was introduced by PCB Manufacturer USA. This was a point of modern touch to enhance the fabrication process with automated soldering technique. The research and development picked up a pace for end to end electronic solutions for defense and US army.
Technical Library | 2013-06-13 15:31:24.0
Electromigration (EM) is a mass transportation mechanism driven by electron wind force, thermal gradient, chemical potential and stress gradient. According to Moore’s law, number of transistors on integrated circuits (ICs) doubles approximately every 2 years. Moore’s law holds true since its introduction in 1970s. This insatiable demand for smaller ICs size, larger integration and higher Input/Output (IO) count of microelectronics has made ball grid array (BGA) the most promising connection type in electronic packaging industry. This trend, however, renders EM reliability of solders joints a major bottleneck to hinder further development of electronics industry...
Electronic Packaging Laboratory, State University of New York
Technical Library | 2023-02-13 18:56:42.0
This paper describes the results of an intensive whisker formation study on Pb-free assemblies with different levels of cleanliness. Thirteen types of as-received surface-mount and pin-through-hole components were cleaned and intentionally contaminated with solutions containing chloride, sulfate, bromide, and nitrate. Then the parts were assembled on double-sided boards that were also cleaned or intentionally contaminated with three fluxes having different halide contents. The assemblies were subjected to high-temperature/high-humidity testing (85_C/85% RH). Periodic examination found that contamination triggered whisker formation on both exposed tin and solder fillets. Whisker occurrence and parameters depending on the type and level of contamination are discussed. Cross-sections were used to assess the metallurgical aspects of whisker formation and the microstructural changes occurring during corrosion.
Technical Library | 2017-10-16 15:03:32.0
The miniaturization and advancement of electronic devices have been the driving force of design, research and development, and manufacturing in the electronic industry. However, there are some issues occurred associated with the miniaturization, for examples, warpage and reliability issues. In order to resolve these issues, a lot of research and development have been conducted in the industry and university with the target of moderate melting temperature solder alloys such as m.p. 280°C. These moderate temperature alloys have not resolve these issues yet due to the various limitations. YINCAE has been working on research and development of the materials with lower temperature soldering for higher temperature application. To meet this demand, YINCAE has developed solder joint encapsulant paste to enhance solder joint strength resulting in improving drop and thermal cycling performance to eliminate underfilling, edge bonding or corner bonding process in the board level assembly process. This solder joint encapsulant paste can be used in typical lead-free profile and after reflow the application temperature can be up to over 300C, therefore it also eliminates red glue for double side reflow process. In this paper, we will discuss the reliability such as strength of solder joints, drop test performance and thermal cycling performance using this solder joint encapsulant paste in detail.
Technical Library | 2023-07-25 16:50:02.0
Some of the new handheld communication devices offer real challenges to the paste printing process. Normally, there are very small devices like 01005 chip components as well as 0.3 mm pitch uBGA along with other devices that require higher deposits of solder paste. Surface mount connectors or RF shields with coplanarity issues fall into this category. Aperture sizes for the small devices require a stencil thickness in the 50 to 75 um (2-3 mils) range for effective paste transfer whereas the RF shield and SMT connector would like at least 150 um (6 mils) paste height. Spacing is too small to use normal step stencils. This paper will explore a different type of step stencil for this application; a "Two-Print Stencil Process" step stencil. Here is a brief description of a "Two-Print Stencil Process". A 50 to 75 um (2-3 mils) stencil is used to print solder paste for the 01005, 0.3 mm pitch uBGA and other fine pitch components. While this paste is still wet a second in-line stencil printer is used to print all other components using a second thicker stencil. This second stencil has relief pockets on the contact side of the stencil any paste was printed with the first stencil. Design guidelines for minimum keep-out distances between the relief step, the fine pitch apertures, and the RF Shields apertures as well relief pocket height clearance of the paste printed by the first print stencil will be provided.
Technical Library | 2020-09-23 21:37:25.0
The need to minimise thermal damage to components and laminates, to reduce warpage-induced defects to BGA packages, and to save energy, is driving the electronics industry towards lower process temperatures. For soldering processes the only way that temperatures can be substantially reduced is by using solders with lower melting points. Because of constraints of toxicity, cost and performance, the number of alloys that can be used for electronics assembly is limited and the best prospects appear to be those based around the eutectic in the Bi-Sn system, which has a melting point of about 139°C. Experience so far indicates that such Bi-Sn alloys do not have the mechanical properties and microstructural stability necessary to deliver the reliability required for the mounting of BGA packages. Options for improving mechanical properties with alloying additions that do not also push the process temperature back over 200°C are limited. An alternative approach that maintains a low process temperature is to form a hybrid joint with a conventional solder ball reflowed with a Bi-Sn alloy paste. During reflow there is mixing of the ball and paste alloys but it has been found that to achieve the best reliability a proportion of the ball alloy has to be retained in the joint, particular in the part of the joint that is subjected to maximum shear stress in service, which is usually the area near the component side. The challenge is then to find a reproducible method for controlling the fraction of the joint thickness that remains as the original solder ball alloy. Empirical evidence indicates that for a particular combination of ball and paste alloys and reflow temperature the extent to which the ball alloy is consumed by mixing with the paste alloy is dependent on the volume of paste deposited on the pad. If this promising method of achieving lower process temperatures is to be implemented in mass production without compromising reliability it would be necessary to have a method of ensuring the optimum proportion of ball alloy left in the joint after reflow can be consistently maintained. In this paper the author explains how the volume of low melting point alloy paste that delivers the optimum proportion of retained ball alloy for a particular reflow temperature can be determined by reference to the phase diagrams of the ball and paste alloys. The example presented is based on the equilibrium phase diagram of the binary Bi-Sn system but the method could be applied to any combination of ball and paste alloys for which at least a partial phase diagram is available or could be easily determined.
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