{"id":422610,"date":"2024-10-20T06:42:03","date_gmt":"2024-10-20T06:42:03","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/bsi-pd-iec-tr-61191-72020-2\/"},"modified":"2024-10-26T12:33:36","modified_gmt":"2024-10-26T12:33:36","slug":"bsi-pd-iec-tr-61191-72020-2","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/bsi\/bsi-pd-iec-tr-61191-72020-2\/","title":{"rendered":"BSI PD IEC TR 61191-7:2020"},"content":{"rendered":"

This part of IEC 61191 serves as a Technical Report and provides information, how technical cleanliness can be assessed within the electronics assembly industry. Technical cleanliness concerns sources, analysis, reduction and control as well as associated risks of particulate matter, so-called foreign-object debris, on components and electronic assemblies in the electronics industry.<\/p>\n

PDF Catalog<\/h4>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
PDF Pages<\/th>\nPDF Title<\/th>\n<\/tr>\n
2<\/td>\nundefined <\/td>\n<\/tr>\n
4<\/td>\nCONTENTS <\/td>\n<\/tr>\n
10<\/td>\nFOREWORD <\/td>\n<\/tr>\n
12<\/td>\nINTRODUCTION <\/td>\n<\/tr>\n
13<\/td>\n1 Scope
2 Normative references
3 Terms and definitions
4 Technical cleanliness
4.1 What is technical cleanliness? <\/td>\n<\/tr>\n
14<\/td>\n4.2 History \u2013 standardisation of technical cleanliness
4.3 Technical cleanliness in the electronics industry
4.4 Potential particle-related malfunctions <\/td>\n<\/tr>\n
15<\/td>\n5 Technical cleanliness as a challenge for the supply chain
5.1 General <\/td>\n<\/tr>\n
16<\/td>\n5.2 Contamination
5.2.1 Definition of particles
5.2.2 Definition of fibres <\/td>\n<\/tr>\n
17<\/td>\n5.3 Test procedure to determine technical cleanliness
5.3.1 Fundamentals <\/td>\n<\/tr>\n
18<\/td>\n5.3.2 Clarification form
Figures
Figure 1 \u2013 Test method as per VDA 19 Part 1 <\/td>\n<\/tr>\n
20<\/td>\n5.3.3 System technology
Figure 2 \u2013 Examples of extraction systems <\/td>\n<\/tr>\n
21<\/td>\n5.3.4 Process parameters for pressure rinsing extraction
5.3.5 Pressure rinsing process <\/td>\n<\/tr>\n
22<\/td>\n5.3.6 Preparing membrane filters for measurement analysis
Figure 3 \u2013 Component holder during manual pressure rinsing <\/td>\n<\/tr>\n
23<\/td>\nFigure 4 \u2013 Examples of different options for drying membrane filters
Figure 5 \u2013 Slide frame with membrane filter <\/td>\n<\/tr>\n
24<\/td>\n5.4 Measurement analysis
5.5 Evaluating the results of cleanliness analyses
5.5.1 Overview <\/td>\n<\/tr>\n
25<\/td>\n5.5.2 Particle count relative to component surface <\/td>\n<\/tr>\n
26<\/td>\n5.5.3 Procedure for violation of action control limits
Figure 6 \u2013 Example procedure if specifications are exceeded
Tables
Table 1 \u2013 Influence of the blank value on the measurement results for different material surfaces (examples for a blank value fraction of 2,2 % and above) <\/td>\n<\/tr>\n
27<\/td>\n5.6 Extended risk assessment
5.6.1 General
5.6.2 Example <\/td>\n<\/tr>\n
28<\/td>\nFigure 7 \u2013 Particle size distribution and corresponding process capability <\/td>\n<\/tr>\n
29<\/td>\n5.7 Component cleanliness \u2013 Data management and visualization
5.7.1 Component cleanliness analysis \u2013 flow diagram
Figure 8 \u2013 Flow diagram for component cleanliness analysis
Figure 9 \u2013 Scope of analytical report <\/td>\n<\/tr>\n
30<\/td>\n5.7.2 Explanation of SCI (Surface Cleanliness Index)
Figure 10 \u2013 Derivation of Illig value <\/td>\n<\/tr>\n
31<\/td>\nFigure 11 \u2013 Derivation of SCI <\/td>\n<\/tr>\n
32<\/td>\nFigure 12 \u2013 Evaluation of 7-pin HV strip connector
Figure 13 \u2013 Graph showing cleaning effect based on SCIs <\/td>\n<\/tr>\n
33<\/td>\n5.7.3 Creating a database
Figure 14 \u2013 Comparison of the three largest particles <\/td>\n<\/tr>\n
34<\/td>\nFigure 15 \u2013 Structural levels of a database
Figure 16 \u2013 Option A \u2013 Evaluation of the largest particles by length and width <\/td>\n<\/tr>\n
35<\/td>\nFigure 17 \u2013 Option B \u2013 Extension to include the degree of contamination \u2013 SCI
Figure 18 \u2013 Option C \u2013 Extension to include a separate data sheet “direct comparison of test series” <\/td>\n<\/tr>\n
36<\/td>\n5.7.4 Summary
Figure 19 \u2013 Option D \u2013 Extension of the database “to include’comparison with customer standards'” <\/td>\n<\/tr>\n
37<\/td>\n6 State of the art \u2013 Technical cleanliness in the electronics industry
6.1 Process flow (per cluster)
6.1.1 General
6.1.2 Electronics manufacturing cluster
Table 2 \u2013 Electronics manufacturing cluster process flow <\/td>\n<\/tr>\n
38<\/td>\n6.1.3 Passive components cluster (e.g. for inductors and aluminium electrolytic capacitors)
Table 3 \u2013 Process flow for inductors <\/td>\n<\/tr>\n
39<\/td>\n6.1.4 Electromechanical components cluster
Table 4 \u2013 Aluminium electrolytic capacitors <\/td>\n<\/tr>\n
40<\/td>\nTable 5 \u2013 Stamped contact production\/plastic production (housing) process flow
Table 6 \u2013 Housing assembly process flow <\/td>\n<\/tr>\n
41<\/td>\n6.1.5 PCB cluster
6.2 Technical cleanliness in the electronics industry \u2013 current situation
6.2.1 General
Table 7 \u2013 PCB cluster process flow <\/td>\n<\/tr>\n
42<\/td>\n6.2.2 Electronics manufacturing
Table 8 \u2013 Empirical data from electronics manufacturing cluster <\/td>\n<\/tr>\n
43<\/td>\n6.2.3 Electronic components
Table 9 \u2013 Empirical data from inductors
Table 10 \u2013 Empirical data from aluminium electrolytic capacitors <\/td>\n<\/tr>\n
44<\/td>\nTable 11 \u2013 Empirical data from tantalum capacitors
Table 12 \u2013 Empirical data from chip components <\/td>\n<\/tr>\n
45<\/td>\nTable 13 \u2013 Empirical data from shunts
Table 14 \u2013 Empirical data from quartz <\/td>\n<\/tr>\n
46<\/td>\n6.2.4 Electromechanical components
Table 15 \u2013 Empirical data from semiconductors
Table 16 \u2013 Empirical data from metallic components \u2013stamping from pre-treated strip stock <\/td>\n<\/tr>\n
47<\/td>\nTable 17 \u2013 Empirical data from metallic components \u2013 stamping of contact from untreated strip stock and subsequent electroplating process
Table 18 \u2013 Empirical data from metallic components \u2013 turning of pins andsubsequent electroplating process <\/td>\n<\/tr>\n
48<\/td>\nTable 19 \u2013 Empirical data from pure plastic parts
Table 20 \u2013 Empirical data from joined strip connectors <\/td>\n<\/tr>\n
49<\/td>\nTable 21 \u2013 Empirical data from high-voltage connectors (typically shielded)
Table 22 \u2013 Empirical data from the assembly process of non-metallic components <\/td>\n<\/tr>\n
50<\/td>\n6.2.5 Metal housings
Table 23 \u2013 Empirical data from die-cast aluminium housing <\/td>\n<\/tr>\n
51<\/td>\n6.2.6 Packaging
6.2.7 Printed circuit boards (PCBs)
Figure 20 \u2013 Flexible circuit board
Table 24 \u2013 Empirical data from deep-drawn trays (new) <\/td>\n<\/tr>\n
52<\/td>\nFigure 21 \u2013 Rigid circuit board
Table 25 \u2013 Empirical data from flexible PCBs without cleaning step <\/td>\n<\/tr>\n
53<\/td>\nTable 26 \u2013 Empirical data from bare, flexible PCBs with cleaning step
Table 27 \u2013 Empirical data from bare, rigid PCBs <\/td>\n<\/tr>\n
54<\/td>\n6.3 Determining potential particle sources in production areas
6.3.1 General
6.3.2 Particle generation
6.3.3 Electronics manufacturing cluster <\/td>\n<\/tr>\n
55<\/td>\n6.3.4 Passive components cluster <\/td>\n<\/tr>\n
56<\/td>\nFigure 22 \u2013 Burr formation on copper wire (D = 2,25 mm) after use of wire-cutter
Figure 23 \u2013 Particles generated by wire cutting D = 1,8 mm (tinned copper) <\/td>\n<\/tr>\n
57<\/td>\nFigure 24 \u2013 Particles generated by wire cutting D = 1,8 mm (tinned copper)
Figure 25 \u2013 Particle (tin) adhering to a tinned copper wire D = 2,25 mm <\/td>\n<\/tr>\n
58<\/td>\nFigure 26 \u2013 Hair-like particle (tin whiskers) chipped off a tinned wire (655 \u00b5m long)
Figure 27 \u2013 Milled enamel wires <\/td>\n<\/tr>\n
59<\/td>\nFigure 28 \u2013 Molten solder balls fused to plastic housings <\/td>\n<\/tr>\n
60<\/td>\nFigure 29 \u2013 Ferrite particle, identified as metallic (419 \u00b5m)
Figure 30 \u2013 Ferrite particle, identified as non-metallic (558 \u00b5m) <\/td>\n<\/tr>\n
61<\/td>\n6.3.5 Electromechanical components cluster
Figure 31 \u2013 Non-metallic particle, probably burr or plastic residue (217 \u00b5m)
Figure 32 \u2013 Non-metallic particle, probably pink polystyrene packaging material <\/td>\n<\/tr>\n
62<\/td>\nFigure 33 \u2013 Shielding plate <\/td>\n<\/tr>\n
63<\/td>\nFigure 34 \u2013 Stamped contacts
Figure 35 \u2013 Connector pin <\/td>\n<\/tr>\n
64<\/td>\nFigure 36 \u2013 Connector housing
Figure 37 \u2013 58-pin connector housing <\/td>\n<\/tr>\n
65<\/td>\n6.3.6 PCB cluster
Figure 38 \u2013 12-pin connector with bridged contacts <\/td>\n<\/tr>\n
66<\/td>\nFigure 39 \u2013 Plastic particles + fibres
Figure 40 \u2013 Plastic particles
Figure 41 \u2013 Metallic particle <\/td>\n<\/tr>\n
67<\/td>\nFigure 42 \u2013 Milling crosses V-scoring line <\/td>\n<\/tr>\n
68<\/td>\nFigure 43 \u2013 V-scoring line on milling edge
Figure 44 \u2013 Chip formation in milled hole <\/td>\n<\/tr>\n
69<\/td>\nFigure 45 \u2013 Edge plating
Figure 46 \u2013 Connections for electroplated gold areas <\/td>\n<\/tr>\n
70<\/td>\nFigure 47 \u2013 Deep milling
Figure 48 \u2013 Chip formation caused by stamping <\/td>\n<\/tr>\n
71<\/td>\nFigure 49 \u2013 Flexible circuit board with undercut
Figure 50 \u2013 Punching burr in hole <\/td>\n<\/tr>\n
72<\/td>\nFigure 51 \u2013 Punching burr
Figure 52 \u2013 Damaged metallic stiffener <\/td>\n<\/tr>\n
73<\/td>\nFigure 53 \u2013 Stamping residue along stamped edge
Figure 54 \u2013 Stamping residue loosened by pickling bath <\/td>\n<\/tr>\n
74<\/td>\n6.4 Cleanliness-controlled design and process selection
6.4.1 Aspects of cleanliness-controlled design\/production with regard to metallic particles
Figure 55 \u2013 Plastic element with burr
Figure 56 \u2013 Particles on externally supplied plastic elements <\/td>\n<\/tr>\n
76<\/td>\n6.4.2 Environmental cleanliness and internal production processes <\/td>\n<\/tr>\n
77<\/td>\nFigure 57 \u2013 Process chain analysis as per VDA 19 Part 2 <\/td>\n<\/tr>\n
78<\/td>\n6.5 Environmental cleanliness analysis and visualisation
6.5.1 General
6.5.2 Procedure for environmental analysis
Figure 58 \u2013 Cleanroom production <\/td>\n<\/tr>\n
79<\/td>\nFigure 59 \u2013 Example particle trap
Figure 60 \u2013 Position of particle trap <\/td>\n<\/tr>\n
80<\/td>\nFigure 61 \u2013 Database \u2013 Visualisation
Figure 62 \u2013 Illustration of the Illig value with max. three particles <\/td>\n<\/tr>\n
81<\/td>\nFigure 63 \u2013 Airborne dispersion diagram
Figure 64 \u2013 Analysis results in the cleanroom <\/td>\n<\/tr>\n
82<\/td>\n6.5.3 Conclusions:
Figure 65 \u2013 Analysis results in the area not governed by VDA 19
Figure 66 \u2013 Weighting of factors influencing technical cleanliness <\/td>\n<\/tr>\n
83<\/td>\n6.6 Cleaning tips
6.6.1 General
6.6.2 Washing
6.6.3 Brushing <\/td>\n<\/tr>\n
84<\/td>\n6.6.4 Suction-cleaning
Figure 67 \u2013 Manual cleaning with brush and illuminated magnifier
Figure 68 \u2013 ESD brush <\/td>\n<\/tr>\n
85<\/td>\n6.6.5 Blowing
6.6.6 Reducing carry-over and controlling cleanliness in workplace design
Figure 69 \u2013 Workstations designed for cleanliness control <\/td>\n<\/tr>\n
86<\/td>\n6.6.7 Adhesive methods
6.7 Packaging and logistics requirements
7 Why do metallic particles in assemblies so rarely cause short circuits?
7.1 General
Figure 70 \u2013 Adhesive roller system for PCB contact cleaning <\/td>\n<\/tr>\n
87<\/td>\n7.2 Probability of contact
7.2.1 Introduction and theory
Figure 71 \u2013 Diagram showing failure risks based on metallic particles on assemblies <\/td>\n<\/tr>\n
88<\/td>\nFigure 72 \u2013 Sketch of electrical arrangement (particle forming “bridge” between two conductors) <\/td>\n<\/tr>\n
89<\/td>\nFigure 73 \u2013 Diagram showing contact point of a particle on a conductor \u2013nickel-gold conductor and copper particle <\/td>\n<\/tr>\n
90<\/td>\n7.2.2 Testing the probability of contact
Table 28 \u2013 List of materials used in the test <\/td>\n<\/tr>\n
91<\/td>\nFigure 74 \u2013 SIR test circuit boards (interleaving comb pattern layout)
Figure 75 \u2013 Voltage source that measures current with an analogue picoamperemeter <\/td>\n<\/tr>\n
92<\/td>\n7.2.3 Results
Figure 76 \u2013 Automated current measurement with software <\/td>\n<\/tr>\n
93<\/td>\nFigure 77 \u2013 Comparison of CU particles in three conditions on SAC305 PCBs
Figure 78 \u2013 Overview of all metals in the voltage classes, rounded <\/td>\n<\/tr>\n
94<\/td>\n7.3 Rinsing extraction versus actual mobility
7.4 Particle sinks <\/td>\n<\/tr>\n
95<\/td>\n7.5 Effect of short circuits on ICs
7.6 Tool for estimating the risk of short circuit
7.6.1 Overview <\/td>\n<\/tr>\n
96<\/td>\n7.6.2 Model hypotheses
Figure 79 \u2013 Functional structure of risk assessment tool <\/td>\n<\/tr>\n
97<\/td>\n7.6.3 Calculation methods
7.6.4 Orientation factor <\/td>\n<\/tr>\n
98<\/td>\n7.6.5 Critical area
Figure 80 \u2013 Geometric constraints at a contact pair <\/td>\n<\/tr>\n
99<\/td>\n7.6.6 Number of particles per size class
Figure 81 \u2013 Clearance areas up to 400 \u00b5m (in white)
Figure 82 \u2013 Clearance areas up to 600 \u00b5m (in white)
Figure 83 \u2013 Clearance areas up to 1000 \u00b5m (in white) <\/td>\n<\/tr>\n
100<\/td>\n7.6.7 Weighting factors <\/td>\n<\/tr>\n
101<\/td>\n7.7 Example use of the risk assessment tool
7.7.1 Example use of the risk assessment tool for calculating failure rate
Figure 84 \u2013 Example calculation 1 \u2013 Calculating an absolute probability of failure <\/td>\n<\/tr>\n
102<\/td>\n7.7.2 Example use of the risk assessment tool for design changes
Figure 85 \u2013 Example calculation 2 \u2013 Calculating probabilities of failurefor layout changes e.g. for a new generation component <\/td>\n<\/tr>\n
103<\/td>\n7.7.3 Example use of the risk assessment tool for specification violations
Figure 86 \u2013 Example calculation 3 \u2013 Optimising the main variables
Figure 87 \u2013 Example calculation 3 \u2013 Calculating the changed probabilityof failure in the event of specification violation <\/td>\n<\/tr>\n
104<\/td>\n8 Summary
9 Outlook <\/td>\n<\/tr>\n
105<\/td>\n10 Related topics
10.1 Filmic contamination
10.1.1 General
10.1.2 Biological films
10.1.3 Chemical films
10.2 Whiskers <\/td>\n<\/tr>\n
106<\/td>\nFigure 88 \u2013 Whiskers growth of > 8 mm over a period of 10 years <\/td>\n<\/tr>\n
107<\/td>\nFigure 89 \u2013 Whiskers growth of > 2 mm over a period of 6 months <\/td>\n<\/tr>\n
108<\/td>\nAnnex A (informative)Determining the surface area of componentsand assembled circuit boards
Figure A.1 \u2013 Dimensions of cuboid components <\/td>\n<\/tr>\n
109<\/td>\nFigure A.2 \u2013 Dimensions of cylindrical components <\/td>\n<\/tr>\n
110<\/td>\nTable A.1 \u2013 Sample values of standard components to determinethe component surface area <\/td>\n<\/tr>\n
111<\/td>\nAnnex B (informative)Examples of cleanliness clarification forms
Figure B.1 \u2013 Ambient cleanliness clarification form <\/td>\n<\/tr>\n
112<\/td>\nFigure B.2 \u2013 Ambient cleanliness clarification form <\/td>\n<\/tr>\n
113<\/td>\nFigure B.3 \u2013 Component cleanliness clarification form <\/td>\n<\/tr>\n
114<\/td>\nFigure B.4 \u2013 Component cleanliness clarification form <\/td>\n<\/tr>\n
115<\/td>\nFigure B.5 \u2013 Component cleanliness clarification form <\/td>\n<\/tr>\n
116<\/td>\nBibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

Printed board assemblies – Technical cleanliness of components and printed board assemblies<\/b><\/p>\n\n\n\n\n
Published By<\/td>\nPublication Date<\/td>\nNumber of Pages<\/td>\n<\/tr>\n
BSI<\/b><\/a><\/td>\n2020<\/td>\n118<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":422618,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[2641],"product_tag":[],"class_list":{"0":"post-422610","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-bsi","8":"first","9":"instock","10":"sold-individually","11":"shipping-taxable","12":"purchasable","13":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/422610","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/422618"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=422610"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=422610"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=422610"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}