PROPER SOLDER PROFILE SET-UP DUE TO PCB CONTAMINATION REDUCTION

Kód výsledku v IS VaVaI

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Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

PROPER SOLDER PROFILE SET-UP DUE TO PCB CONTAMINATION REDUCTION

Popis výsledku v původním jazyce

This article will present the results of testing of ionic cleanliness of PCB in dependence on a soldering profile. Implementation of lead-free solder alloys changed the soldering process. Higher soldering temperatures are used due to higher melting points of alloys. Therefore it was necessary to use another types of fluxes (mostly with higher activity) in order to remove oxides during the soldering process. Fluxes are more aggressive and their residues after soldering can cause undesired issues in electronic assemblies. The largest database of soldering defects (Soldering Defects Database) states that the influence of fluxes and residues causes a quarter of all defects in soldering. The most common defects are dendrites and corrosion resulting from external influences (increased humidity, temperature, voltage) on active flux residues after the soldering process. These defects can be prevented by implementing of PCB cleaning in the production and measurement of ionic cleanliness. One of the important questions is to determine how to measure board cleanliness reliably and which "clean" PCB can be truly considered as clean. International Standard IPC-TM-650 specifies that the allowable level of PCB pollution after soldering is 1.56 ?g NaCl/cm2, but this standard was published in a time when electronic assemblies did not contain so many components and were not as complicated as it is nowadays. Therefore, it is important to realize whether this value is still suitable for "modern" electronic assemblies.

Název v anglickém jazyce

PROPER SOLDER PROFILE SET-UP DUE TO PCB CONTAMINATION REDUCTION

Popis výsledku anglicky

This article will present the results of testing of ionic cleanliness of PCB in dependence on a soldering profile. Implementation of lead-free solder alloys changed the soldering process. Higher soldering temperatures are used due to higher melting points of alloys. Therefore it was necessary to use another types of fluxes (mostly with higher activity) in order to remove oxides during the soldering process. Fluxes are more aggressive and their residues after soldering can cause undesired issues in electronic assemblies. The largest database of soldering defects (Soldering Defects Database) states that the influence of fluxes and residues causes a quarter of all defects in soldering. The most common defects are dendrites and corrosion resulting from external influences (increased humidity, temperature, voltage) on active flux residues after the soldering process. These defects can be prevented by implementing of PCB cleaning in the production and measurement of ionic cleanliness. One of the important questions is to determine how to measure board cleanliness reliably and which "clean" PCB can be truly considered as clean. International Standard IPC-TM-650 specifies that the allowable level of PCB pollution after soldering is 1.56 ?g NaCl/cm2, but this standard was published in a time when electronic assemblies did not contain so many components and were not as complicated as it is nowadays. Therefore, it is important to realize whether this value is still suitable for "modern" electronic assemblies.

Druh

D - Stať ve sborníku

CEP obor

JA - Elektronika a optoelektronika, elektrotechnika

OECD FORD obor

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Projekt

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Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2014

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Electronic devices and systems : IMAPS CS international conference : proceedings

ISBN

978-80-214-4985-5

ISSN

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e-ISSN

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Počet stran výsledku

6

Strana od-do

54-59

Název nakladatele

Vysoké učení technické

Místo vydání

Brno

Místo konání akce

Brno

Datum konání akce

25. 6. 2014

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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