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SMTnet Express, January 25, 2024, Subscribers: 25,319, Companies: 12,002, Users: 28,668

█ Electronics Manufacturing Technical Articles

Cracks in ceramic chip capacitors can be introduced at any process step during surface mount assembly. Thermal shock has become a "pat" answer for all of these cracks, but about 75 to 80% originate from other sources. These sources include ...

Credits: AVX Corporation

Flex Crack Mitigation

As part of continuous process improvement at KEMET, most failure modes caused by the capacitor manufacturing process have been systematically eliminated. Today these capacitor manufacturing-related defects are now at a parts per billion (PPB) level. Pareto analysis of customer complaints indicates ...

Credits: KEMET Electronics Corporation

Cracking Problems in Low-Voltage Chip Ceramic Capacitors

Cracking remains the major reason of failures in multilayer ceramic capacitors (MLCCs) used in space electronics. Due to a tight quality control of space-grade components, the probability that as manufactured capacitors have cracks is relatively low, and cracking is often occurs during assembly, handling and the following testing of the systems. Majority of capacitors with cracks are revealed during the integration and testing period, but although extremely rarely, defective parts remain undetected and result in failures during the mission. Manual soldering and rework that are often used during low volume production of circuit boards for space aggravate this situation. Although failures of MLCCs are often attributed to the post-manufacturing stresses, in many cases they are due to a combination of certain deviations in the manufacturing processes that result in hidden defects in the parts and excessive stresses during assembly and use. This report gives an overview of design, manufacturing and testing processes of MLCCs focusing on elements related to cracking problems. The existing and new screening and qualification procedures and techniques are briefly described and assessed by their effectiveness in revealing cracks. The capability of different test methods to simulate stresses resulting in cracking, mechanisms of failures in capacitors with cracks, and possible methods of selecting capacitors the most robust to manual soldering stresses are discussed.

Credit: NASA Office Of Safety And Mission Assurance

Avoidance of Ceramic-Substrate-Based LED Chip Cracking Induced by PCB Bending or Flexing

Printed circuit board (PCB) bending and/or flexing is an unavoidable phenomenon that is known to exist and is easily encountered during electronic board assembly processes. PCB bending and/or flexing is the fundamental source of tensile stress induced on the electronic components on the board assembly. For more brittle components, like ceramic-based electronic components, micro-cracks can be induced, which can eventually lead to a fatal failure of the components. For this reason, many standards organizations throughout the world specify the methods under which electronic board assemblies must be tested to ensure their robustness, sometimes as a pre-condition to more rigorous environmental tests such as thermal cycling or thermal shock.

Credit: Cree Lighting

Effect of PCB cracks on thermal cycling reliability of passive microelectronic components with single-grained solder joints

Lead-free tin-based solder joints often have a single-grained structure with random orientation and highly anisotropic properties. These alloys are typically stiffer than lead-based solders, hence transfer more stress to printed circuit boards (PCBs) during thermal cycling. This may lead to cracking of the PCB laminate close to the solder joints, which could increase the PCB flexibility, alleviate strain on the solder joints, and thereby enhance the solder fatigue life. If this happens during accelerated thermal cycling it may result in overestimating the lifetime of solder joints in field conditions. In this study, the grain structure of SAC305 solder joints connecting ceramic resistors to PCBs was studied using polarized light microscopy and was found to be mostly single-grained. After thermal cycling, cracks were observed in the PCB under the solder joints. These cracks were likely formed at the early stages of thermal cycling prior to damage initiation in the solder. A finite element model incorporating temperature-dependent anisotropic thermal and mechanical properties of single-grained solder joints is developed to study these observations in detail. The model is able to predict the location of damage initiation in the PCB and the solder joints of ceramic resistors with reasonable accuracy. It also shows that the PCB cracks of even very small lengths may significantly reduce accumulated creep strain and creep work in the solder joints. The proposed model is also able to evaluate the influence of solder anisotropy on damage evolution in the neighbouring (opposite) solder joints of a ceramic resistor.

Credit: Research Institutes of Sweden

Solder Crack Counter Measures

This page introduces major causes and countermeasures of solder crack in MLCCs (Multilayer Ceramic Chip Capacitors). Major causes of solder cracks Solder cracks on MLCCs developed from severe usage conditions after going on the market and during manufacturing processes such as soldering. Applications and boards that specially require solder crack countermeasures Solder cracks occur mainly because of thermal fatigue due to thermal shock or temperature cycles or the use of lead-free solder, which is hard and fragile.

Credit: TDK - Lambda Americas

Analysis of Interfacial Cracking in Flip Chip Packages With Viscoplastic Solder Deformation

This paper examines the modeling of viscoplastic solder behavior in the vicinity of interfacial cracking for flip chip semiconductor packages. Of particular interest is the relationship between viscoplastic deformation in the solder bumps and any possible interface cracking between the epoxy underfill layer and the silicon die. A 3-D finite element code, developed specifically for the study of interfacial fracture problems, was modified to study how viscoplastic solder material properties would affect fracture parameters such as strain energy release rate and phase angle for nearby interfacial cracks. Simplified twolayer periodic symmetry models were developed to investigate these interactions. Comparison of flip chip results using different solder material models showed that viscoplastic models yielded lower stress and fracture parameters than time independent elastic-plastic simulations. It was also found that adding second level attachment greatly increases the magnitude of the solder strain and fracture parameters. As expected, the viscoplastic and temperature dependent elastic-plastic results exhibited greater similarity to each other than results based solely on linear elastic properties. !DOI: 10.1115/1.1649242"

Credit: Lehigh University

RESULTS of Searches for related keywords - "chip cracking" (161)

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█ Printed Circuit Board Assembly & PCB Design Forum

Installing tools on a MyData MY12 -- For some reason I cannot load any tools on my MY12 machine. The machine goes through the motions like its loading the tool (grabbing it and putting it back) but at the very end it moves the carriage all the way to the right and wants me to put the tool in manualy (even though its already in the Midas) and it just keeps doing this without installing it. I don't get it. Another problem I have is when I try to install C14, the machine goes to C23 tool. Anyone know why? Thanks in advance.

SPI and AOI IPC Requirements -- Is there any stardarts to help us what tolerance values (max or min. height, weight, volume etc) should we use while programming AOI and SPI.

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█ SMT, PCB Electronics Assembly Manufacturing Industry News

Koh Young Shares Inspection Solutions at the SMTA Wafer-Level Packaging Symposium12 February 2024 Koh Young Technology, the leader in True3D™ measurement-based inspection solutions, will be speaking at the SMTA Wafer-Level Packaging Symposium in Burlingame, California on our Multimodal Phase Shift Optics Approach to revolutionize high-speed 3D reconstruction of semiconductor and advanced packages. In the presentation will highlight how high-speed 3D reconstruction addresses the growing demand for electronic components, which necessitates fast and efficient processing. These advancements in measurement technology and AI integration have paved the way for enhanced packaging applications in the semiconductor industry.... Koh Young America, Inc.
I.C.T. Double-Sided PCBA Coating Line: Enhances Surface Protection, Efficiency for Diverse Industries I.C.T introduces the PCB Double-Sided Coating Line, a cutting-edge solution catering to diverse manufacturing needs. This innovative technology enhances surface coating capabilities for PCBs, addressing the evolving demands of the industry.... I.C.T ( Dongguan ICT Technology Co., Ltd. )
Totech Canada Inc Partners with MP Dry Cabinet Toyo Living authorized dry cabinet distributor Totech Canada inc is proud to announce the sales and after sales service partnership with MP dry cabinets ,we are pleased to offer MP dry cabinet intelligent series dry cabinets to all our clients as a added option to our already well known Toyo living style standalone economically price Totech Dry cabinets in the American markets.. MP Dry cabinets brings a wide range of fully networkable advanced controlled solutions... TOTECH Canada N.A Inc

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█ SMT / PCB Products & Services

NEW SMT / PCB EQUIPMENT & SERVICES - For Sale

PCB INSPECTION

MS-15 High Speed In-Line SPI System

Mirtec

PCB SOFTWARE

ProntoGERBER CONNECTION

Unisoft

PCB ASSEMBLY

PCB Fab & Assembly

Imagineering

PCB REFLOW OVEN

Flux-Free Formic Acid Reflow Oven

Heller

PCB COATING

SimpleCoat Selective Conformal Coating

GPD Global

Reflow

PCB Reflow Oven Machine I.C.T Lyra Series

Dongguan I.C.T

SELECTIVE SOLDERING

Pillarhouse Jade Handex

Pillarhouse USA

VIEW MORE NEW PRODUCTS...

█ SMT / PCB Assembly Equipment Auctions

AUCTION | Surplus to Creation Technologies SMT Facility

AUCTIONEER | The Branford Group

TYPE | Online Auction

SCHEDULE | Mon, Feb 12 to Wed, Feb 14, 2024

Auction Opening: Monday, February 12, 2024 9:00 AM (MST)

Begins Closing: Wednesday, February 14, 2024 10:00 AM (MST)

LOCATION | 1450 Mission Ave NE, Albuquerque, NM 87107 USA

█ Electronic Equipment Market

MARKET - Used Electronic Assembly Machines For Sale

AOI INSPECTION

Viscom S3088 Ultra Chrome 3D AOI

Lewis & Clark Viscom S3088 AOI

Lewis & Clark

Board Cleaners

Aqueous Technologies Trident XLD

Baja Bid

P&P / FEEDERS

Panasonic NPM-W2

SMTUnion - Panasonic NPM-W2 Chipshooter

SMTUnion

PCB LABELING

Coherent Verdi V18 SOLID-STATE Diode-Pumped Laser

World Equipment Source - Coherent Diode-Pumped Laser

World Equipment Source, LLC

Adhesive Dispensers

Musashi FAD2500

KD Electronics Ltd.

MORE EQUIPMENT & PARTS...

SUBMIT YOUR RFQ ....

MARKET - Used PCB Assembly Equipment Wanted To Buy

P&P / FEEDERS

Assembleon MG-1R

World Equipment Source Assembleon MG-1R

World Equipment Source, LLC

PCB TEST

Agilent 3070

Lewis & Clark Agilent 3070

Lewis & Clark

PCB TEST

Agilent 3070

KD Electronics Agilent 3070

KD Electronics

Soldering - Reflow

Vitronics XPM 1240

Baja Bid

SEE Buyers' Used Assembly Equipment Wants

█ Electronics Manufacturing & Assembly Events Calendar

EVENTS

Pan Pacific Strategic Electronics Symposium | January 29 to February 1, 2024

SMTA

Wafer-Level Packaging Symposium | February 14 to 16, 2024

SMTA

█ Electronics Manufacturing Training Courses & PCB Assembly Training

FIND TRAINING FOR:

IPC Certification

Soldering & Rework

PCB Design

Electronics Assembly

Electronics Inspection

Online Training

TRAINING - PCB Inspection Electronics Manufacturing Training Courses

IPC-A-610 Specialist Interactive PCB Inspection Lab (CIS or CIT Option) Certification Training Course

Multiple dates and locations. Check the link for details

EPTAC Corporation

TRAINING - PCB Rework and Hand Soldering Training Courses

Customizable Basic Hand Soldering

Multiple dates and locations. Check the link for details

Blackfox Training Institute, LLC

EPTAC Hand Soldering Certification Training Course

Multiple dates and locations. Check the link for details

EPTAC Corporation

TRAINING - Online Electronics Manufacturing and Assembly Training Courses

Reflow Soldering 101 Training Course

Surface Mount Technology Association (SMTA)

IPC/WHMA-A-620 Expert (CSE) Certification Training Course

EPTAC Corporation

IPC Certified Electronics Program Manager (CEPM) Training and Certification Program

Association Connecting Electronics Industries (IPC)

Component Placement 101 Training Course

Surface Mount Technology Association (SMTA)

ESD Control for Electronics Assembly

Association Connecting Electronics Industries (IPC)

MORE TRAINING COURSES...

█ Electronics Manufacturing & PCB Assembly Career Center

Job Needs & Wants

JOBS

YOUR job openings

Overseas SMT Engineer

All over the world, Alabama, USA

I.C.T ( Dongguan Intercontinental Technology Co., Ltd. )

SMT Engineer, Marketing Representative, Sales Representative, Business Assistant

All over the world, California, USA

I.C.T ( Dongguan Intercontinental Technology Co., Ltd. )

Installation Service Technician

Centennial, Colorado, USA

Vortex Industries

AOI Engineer

Hai Phong, Vietnam

Dongguan RuiHengHuaTai Electronic Co., Ltd

SMT Process Technician III

Racine, Wisconsin, USA

Cree Lighting

Experienced SAKI AOI programmer

All US, USA

AirDataIOT,LLC

Engineering Project Manager

Strongsville, Ohio, USA

Spartronics

Senior Quality Engineer

Williamsport, Pennsylvania, USA

Spartronics

Senior Systems Engineer

Strongsville, Ohio, USA

Spartronics

Procurement Specialist

Brooksville, Florida, USA

Spartronics

Buyer/Planner

Williamsport, Pennsylvania, USA

Spartronics

Corporate Director of Quality

Williamsport, Pennsylvania, USA

Spartronics

Automotive service Technician

Golden, CO, USA

Engage2excel

Program Manager

Williamsport, Pennsylvania, USA

Spartronics

RESUMES

YOUR resumes

POSITION: Equipment Incharge

JOB CATEGORY: Engineering , Production

CURRENT LOCATION: Tirupati, India

WILLING TO RELOCATE?: Not willing to relocate.

SUMMARY OF QUALIFICATIONS: 2 years experience on NeoLync in equipment incharge.

YOUR next job ... YOUR next employee ...

█ PCB Design & Assembly Industry Associations

Surface Mount Technology Association (SMTA)

SMTA is a non-profit international association of companies and individuals (totalling 4,000) involved in all aspects of advanced electronics assembly, surface mount and related technologies.

Membership Info | SMTA Certification | Bookstore | Upcoming Events

Association Connecting Electronics Industries (IPC)

IPC is a US-based trade association dedicated to the competitive excellence and financial success of its nearly 2,600 member companies which represent all facets of the electronic interconnection industry, including design, printed wiring board manufacturing and electronics assembly.

Membership Info | Training & Certification | Online Store | Upcoming Events

Editor - Dave "davef" Fish (submit your technical articles)

SMTnet.com, 98 Elm Street, Portland, Maine 04101 USA, Tel.207-780-0887.

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