Electronics Manufacturing Technical Articles

Papers and articles related to SMT, PCB & EMS industry.

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1802 SMT / PCB Assembly Related Technical Articles

Governing Autonomous Vehicles: Emerging Responses For Safety, Liability, Privacy, Cybersecurity, And Industry Risks

Jul 31, 2023 | Araz Taeihagh and Hazel Si Min Lim

The benefits of autonomous vehicles (AVs) are widely acknowledged, but there are concerns about the extent of these benefits and AV risks and unintended consequences. In this article, we first examine AVs and different categories of the technological risks associated with them. We then explore strategies that can be adopted to address these risks, and explore emerging responses by governments for addressing AV risks. Our analyses reveal that, thus far, governments have in most instances avoided stringent measures in order to promote AV developments and the majority of responses are non-binding and focus on creating councils or working groups to better explore AV implications. The US has been active in introducing legislations to address issues related to privacy and cybersecurity. The UK and Germany, in particular, have enacted laws to address liability issues; other countries mostly acknowledge these issues, but have yet to implement specific strategies. To address privacy and cybersecurity risks strategies ranging from introduction or amendment of non-AV specific legislation to creating working groups have been adopted. Much less attention has been paid to issues such as environmental and employment risks, although a few governments have begun programmes to retrain workers who might be negatively affected....

Publisher: National University of Singapore

National University of Singapore

The National University of Singapore is a national research university based in Singapore. Founded in 1905 as the Straits Settlements and Federated Malay States Government Medical School, NUS is the oldest autonomous university...

Singapore, Singapore

Research Institute / Laboratory / School

A Safety Standard Approach for Fully Autonomous Vehicles

Jul 31, 2023 | Philip Koopman, Uma Ferrell, Frank Fratrik, Michael Wagner

Assuring the safety of self-driving cars and other fully autonomous vehicles presents significant challenges to traditional software safety standards both in terms of content and approach. We propose a safety standard approach for fully autonomous vehicles based on setting scope requirements for an overarching safety case. A viable approach requires feedback paths to ensure that both the safety case and the standard itself co-evolve with the technology and accumulated experience. An external assessment process must be part of this approach to ensure lessons learned are captured, as well as to ensure transparency. This approach forms the underlying basis for the UL 4600 initial draft standard.

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Publisher: Edge Case Research

Edge Case Research

Edge Case is the trusted risk-management partner for companies building self-driving trucks, autonomous robotaxis, and smarter passenger cars. We help developers and operators measure, manage, and insure the risks posed by softwar

Pittsburgh, Pennsylvania, USA

Consultant / Service Provider

High-precision dispensing technology: Potting technology for medical wearables

Jul 27, 2023 | Scheugenpflug

Diabetes affects many millions of people worldwide. New technology for real-time glucose measurement replaces the usual unpleasant pricking of a finger: a sensor located in the subcutaneous tissue of the diabetes patient measures the glucose values and transmits them to a receiver. Production of such medical wearables calls for high-precision dispensing systems for applying very small amounts of UV adhesives to medical PCBs and for integrated system concepts to achieve this. A perfect task for Scheugenpflug....

Publisher: Scheugenpflug Inc.

Scheugenpflug Inc.

Producer of bonding, dispensing and potting solutions with outstanding expertise in automation. As part of the Atlas Copco Group, we have a worldwide sales & service network and access to the Group's extensive technology portfolio

Kennesaw, Georgia, USA

Manufacturer

A Study of the Aperture Filling Process in Solder Paste Stencil Printing

Jul 25, 2023 | Jianbiao Pan, G. Tonkay

Stencil printing has been the dominant method of solder deposition in surface mount assembly. With the development of advanced packaging technologies such as ball grid array (BGA) and flip chip on board (FCOB), stencil printing will continue to play an important role. However, the stencil printing process is not completely understood because 52–71 percent of fine and ultra-fine pitch surface mount assembly defects are printing process related (Clouthier, 1999). This paper proposes an analytical model of the solder paste deposition process during stencil printing. The model derives the relationship between the transfer ratio and the area ratio. The area ratio is recommended as a main indicator for determining the maximum stencil thickness. This model explains two experimental phenomena. One is that increasing stencil thickness does not necessarily lead to thicker deposits. The other is that perpendicular apertures print thicker than parallel apertures....

Publisher: Lehigh University

Lehigh University

Located in Pennsylvania's beautiful Lehigh Valley, Lehigh is one of the nation's most distinguished private research universities. Through academic rigor, an entrepreneurial mindset and collaborative opportunities we challenge our

Bethlehem, Pennsylvania, USA

Research Institute / Laboratory / School

Solder Paste Deposition Project Report

Jul 25, 2023 | Cherie Chen

INTRODUCTION: ...

Publisher: iNEMI (International Electronics Manufacturing Initiative)

iNEMI (International Electronics Manufacturing Initiative)

iNEMI is an industry-led consortium focused on identifying and closing technology gaps, which includes the development and integration of the electronics industry supply infrastructure.

Herndon, Virginia, USA

Step Stencil design when 01005 and 0.3mm pitch uBGA's coexist with RF Shields

Jul 25, 2023 | William E. Coleman Ph.D.

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....

Publisher: Photo Stencil LLC

Photo Stencil LLC

Photo Stencil provides high-performance stencils, squeegee blades, thick film and metal mask screens and tooling for the surface mount technology (SMT) assembly, solar, and semiconductor industries.

Colorado Springs, Colorado, USA

Manufacturer

Stencil Options for Printing Solder Paste for .3 Mm CSP's and 01005 Chip Components

Jul 25, 2023 | William E. Coleman Ph.D. , Chris Anglin

Printing solder paste for very small components like .3mm pitch CSP's and 01005 Chip Components is a challenge for the printing process when other larger components like RF shields, SMT Connectors, and large chip or resistor components are also present on the PCB. The smaller components require a stencil thickness typically of 3 mils (75u) to keep the Area Ratio greater than .55 for good paste transfer efficiency. The larger components require either more solder paste height or volume, thus a stencil thickness in the range of 4 to 5 mils (100 to 125u). This paper will explore two stencil solutions to solve this dilemma. The first is a "Two Print Stencil" option where the small component apertures are printed with a thin stencil and the larger components with a thicker stencil with relief pockets for the first print. Successful prints with Keep-Outs as small as 15 mils (400u) will be demonstrated. The second solution is a stencil technology that will provide good paste transfer efficiency for Area Ratio's below .5. In this case a thicker stencil can be utilized to print all components. Paste transfer results for several different stencil types including Laser-Cut Fine Grain stainless steel, Laser-Cut stainless steel with and w/o PTFE Teflon coating, AMTX E-FAB with and w/o PTFE coating for Area Ratios ranging from .4 up to .69....

Publisher: Photo Stencil LLC

Photo Stencil LLC

Photo Stencil provides high-performance stencils, squeegee blades, thick film and metal mask screens and tooling for the surface mount technology (SMT) assembly, solar, and semiconductor industries.

Colorado Springs, Colorado, USA

Manufacturer

Stencil Print solutions for Advance Packaging Applications

Jul 25, 2023 | Phani Vallabhajosyula, PhD

This paper address two significant applications of stencils in advance packaging field: 1. Ultra-Thin stencils for miniature component (0201m) assembly; 2. Deep Cavity stencils for embedded (open cavity) packaging. As the world of electronics continues to evolve with focus on smaller, lighter, faster, and feature-enhanced high- performing electronic products, so are the requirement for complex stencils to assemble such components. These stencil thicknesses start from less than 25um with apertures as small as 60um (or less). Step stencils are used when varying stencil thicknesses are required to print into cavities or on elevated surfaces or to provide relief for certain features on a board. In the early days of SMT assembly, step stencils were used to reduce the stencil thickness for 25 mil pitch leaded device apertures. Thick metal stencils that have both relief-etch pockets and reservoir step pockets are very useful for paste reservoir printing. Electroform Step-Up Stencils for ceramic BGA's and RF Shields are a good solution to achieve additional solder paste height on the pads of these components as well as providing exceptional paste transfer for smaller components like uBGAs and 0201s. As the components are getting smaller, for example 0201m, or as the available real estate for component placement on a board is getting smaller – finer is the aperture size and the pitch on the stencils. Aggressive distances from step wall to aperture are also required. Ultra-thin stencils with thicknesses in the order of 15um-40um with steps of 15um are used to obtain desired print volumes. Stencils with thickness to this order can be potential tools even to print for RDLs in the package....

Publisher: Photo Stencil LLC

Photo Stencil LLC

Photo Stencil provides high-performance stencils, squeegee blades, thick film and metal mask screens and tooling for the surface mount technology (SMT) assembly, solar, and semiconductor industries.

Colorado Springs, Colorado, USA

Manufacturer

KE-2050/KE-2060 Causes and Countermeasures of Patch Failure

Jul 22, 2023 | KSUNSMT

Patch offset; Uneven patches throughout the substrate (each substrate is offset in a different way); Only part of the substrate is offset; Only certain components are offset; The patch Angle is offset; Component absorption error; Laser identification (component identification) error; Nozzle loading and unloading error; Mark (BOC mark, IC mark) identification error; Image recognition error (KE-2060 only); Analysis of the main reasons for throwing material. More information about KINGSUN please Contact US at jenny@ksunsmt.com or visit www.ksunsmt.com...

Publisher: DONGGUAN KINGSUN AUTOMATION TECHNOLOGY CO.,LTD

DONGGUAN KINGSUN AUTOMATION TECHNOLOGY CO.,LTD

DONGGUAN KINGSUN AUTOMATION TECHNOLOGY CO.,LTD is a company which mainly provide used and new SMT parts, provide repair SMT key parts service,new/used SMT machine trading,SMT consumables and Peripherals equipment,Clean room, ESD..

Dongguan, China

Consultant / Service Provider, Distributor, Equipment Dealer / Broker / Auctions, Manufacturer, Manufacturer's Representative