Peter Burnley MIT Technology Centre Manager Electronics Yorkshire Eric Hinsley Senior Tutor Electronics Yor

2. Peter Burnley MIT Technology Centre Manager Electronics Yorkshire Eric Hinsley Senior Tutor Electronics Yorkshire

3. Introduction to IPC Overview of IPC Design & Acceptance Standards Implementation of a Manufacturable Design Quality & Inspection Founded in 1957 by six companies, IPC was established as an association to assist the printed circuit board industry in flourishing. Focusing our efforts on design, manufacturing and assembly of printed circuit boards, IPC has grown to over 2300 member companies worldwide. Founded in 1957 by six companies, IPC was established as an association to assist the printed circuit board industry in flourishing. Focusing our efforts on design, manufacturing and assembly of printed circuit boards, IPC has grown to over 2300 member companies worldwide.

4. IPC is a Technical Organization that meets Industry Requirements as it is driven by Industry There are many committees that sit regularly to discuss the changes that are happening in the industry The standards and certifications are updated regularly Founded in 1957 by six companies, IPC was established as an association to assist the printed circuit board industry in flourishing. Focusing our efforts on design, manufacturing and assembly of printed circuit boards, IPC has grown to over 2300 member companies worldwide. Founded in 1957 by six companies, IPC was established as an association to assist the printed circuit board industry in flourishing. Focusing our efforts on design, manufacturing and assembly of printed circuit boards, IPC has grown to over 2300 member companies worldwide.

5. Applicable IPC Standards 4 Design -7351; Land Pattern Considerations (IPC782) -7095; BGA Process Implementation -2315; HDI & Microvia Design Guide -2220; Design for Manufacture -D-279; Design for SMT Reliability J-STD-001; Soldering Requirements -A-610; Assembly Acceptability -6010; Printed Board Series J-STD-004/005; Solder Flux/Paste IPC-1752; Material Declaration

6. International Organizations ISO - International Organization for Standardization Deals mostly with Mechanical Standards IEC - International Electrotechnical Commission Deals mostly with Electrical / Electronic Standards. Both ISO & IEC managed from same location in Geneva, Switzerland Occasional overlap between ISO and IEC programming Both require participating Country support

7. IPC defines 3 levels of product quality for Manufactures to build to and designers to aim for. Class 1 - General Electronic Products Class 2 - Dedicated Service Electronic Products Class 3 - High Reliability Electronic Products There are more defined classifications within the sub categories of IPC standards

8. Overview of IPC Design & Acceptance Standards

9. Design & Acceptance Covers The guidelines are constantly evolving on Rigid, Flex boards and assemblies, pc cards, modules, embedded passive components Other new technologies intended to address tighter tolerances, greater electrical capabilities and increased product performance requirements. Consideration is also given on CAD/CAM capability and data transfer from supply source.

10. Electronic Equipment Design IPC-2221 Generic Standard on Printed Board Design IPC-2222 Sectional Standard on Rigid Organic Printed Boards IPC-2223 Sectional Design Standard for Flexible Printed Boards IPC-2224 Sectional Standard of Design of PWB for PC Cards IPC-2225 Sectional Design Standard for Organic Multichip Modules (MCM-L) and MCM-L Assemblies IPC-2226 Sectional Design Standard Guide for High Density Interconnects & Microvias IPC-2315 Design Guide for High Density Interconnects & Microvias IPC-2316 Design Guide for Embedded Component Technology(will become IPC-2227)

11. What�s Involved in theDocumentation Package Fabrication Drawings Assembly Drawings Bill of Materials Schematic or Logic Diagrams Wiring Diagrams Specification Control Drawings Electronic Data Mechanical Drawings

12. Design Issues Land pattern concepts Component selection Mounting substrate design Assembly methods Method of test Phototool generation Meeting solder joint requirements Stencil fixture requirements Providing access for inspection Access for rework and repair

13. Manufacturing Allowance The courtyard represents the starting point of the minimum area needed for the component and the land pattern Manufacturing allowance must be considered in the design process Manufacturing, assembly and testing representatives should be involved in determining the additional room needed to accommodate placement, testing, modification and rework

14. IPC-7351 Land Pattern Software

15. What�s Next? New Design Standards Major support by CAD tool providers National Institute Standard Technology (NIST) viewer can be used to check data files NIST Gerber to IPC-2581 conversion New tools becoming available daily

16. Material Selection

17. Material Requirements Cover Existing standards New materials being developed to meet higher temperature assembly due to lead free implementation Assembly materials Requirement for halogen free laminate

18. Standards for Laminates Flexible Laminate Rigid and HDI Laminate Foil-Laminate

19. PCB Base Material Base materials for printed board applications are changing faster than at any point in their short 45 year history. FR-4 is improving technically to facilitate Lead-free assembly Halogen-free assembly Global market place requires global specifications With new materials and technologies developed rapidly, governing standards must be generated just as fast in order to maintain a cohesive pattern of control

20. Key Material Properties

21. Solder Alloy Selection

22. Printed Board Process Characteristics 

23. Surface Finish HASL - hot air solder leveling OSP - organic solderability preservative ENIG - electro less nickel immersion gold ImAg - immersion silver ImSn - immersion tin New Developments include DIG Direct Immersion Gold

24. Related Process Issues Solder paste application (volume control) Tented or plugged vias Solder flux removal vs flux residue Impact of wave soldering Partially filled vias

25. Workmanship &Discrimination Standards

26. Standards of Workmanship Any training provided should be across the board and not just to operators so that everyone understands the design and performance intent. Discuss both the mounting structure and the assembly end product characteristics Need for describing the manufacturing target condition Compares acceptable workmanship as well as rejected or process indicator criteria.

27. Acceptance IPC-A-600G Acceptability of Printed Boards IPC-A-610D Acceptability of Electronic Assemblies IPC-WHMA-A-620A Requirements & Acceptance for Cable & Wire Harness Assemblies

28. Workmanship IPC J-STD-001D Requirements for Soldering Electrical & Electronic Assemblies IPC-7711A & IPC-7721A Rework of Electronic Assemblies Repair and Modification of PCB�s and electronic Assemblies

30. Acceptance Acceptance of product for delivery shall be based on product that has passed the testing requirements shown in the applicable Performance Specification and User defined documentation.

31. Quality and Inspection

32. Quality Assessment Covers existing standards Test method and techniques used to evaluate the products that are part of the electronic equipment Addresses techniques for process control, how these should be applied and sampling plan characteristics Industry best practice criteria for the products in question.

33. Process Control Elements Key Process Control Variables Incoming Material Design For Manufacture (DFM) Manufacturing Processes Training Documentation

34. Key Considerations forImproving Yield Finer the pitch, more difficult is the implementation of design & manufacture. With reduced pitch, precision becomes more intense and process windows tighten Lower yield and higher cost if design is not precise and processes are not very tightly controlled With the widespread use of smaller and smaller components with finer and finer pitches, the problem is simply compounded

35. Common Quality Control Techniques: Trial and Error Trial Error methods are expensive, time consuming and can be frustrating. The processes are incredibly high speed. They must be performed by machines. The equipment must be thoroughly characterized. Most large companies have assigned engineers to optimize; small companies �learn as they go�. �Learn as you go� is not a real option, since revenue or product schedule or both may be adversely impacted. Fine pitch, BGA, CSP, 0402, 0201, 01005, thin PCB�s and, no-clean flux compound the yield problems

36. Design to Improve ManufacturingFirst Pass Yield Must understand the interdependency of design, incoming materials and manufacturing processes Then and only then can we achieve higher yield, lower cost and faster time to market This requires considerable investment of engineering resources at all levels in a) Process characterization b) Training not just for ENGINEERS but MANUFACTURING and support staff c) Documentation

37. DFM is one of the key drivers of manufacturing yield

38. DFM is one of the key drivers of manufacturing yield Very few circuit & board designers have a good understanding of manufacturing

39. DFM is one of the key drivers of manufacturing yield Very few circuit & board designers have a good understanding of manufacturing So it is common to blame manufacturing for all the yield problems since that is where defects are discovered

40. Incoming Materials Quality �Garbage in = garbage out� There is no way to improve manufacturing yield if Boards and components have poor solderability Paste is susceptible to slumping & solder balling Flux is not compatible with the process, boards or components Purchasing are unaware of the requirements of the above issues. Must communicate clearly with suppliers on specific process requirements. Remember: Industry standards are not procurement specs Demand materials meet your requirements for which you are paying.

41. Manufacturing Processes & Equipment Once the problems in design and incoming materials have been addressed, it is time to focus on the manufacturing processes and equipment to improve yield and expenses How should one go about identifying the key manufacturing process issues? First characterize the process Document the details of equipment and non-equipment dependent variables that control yield. This document serves as the process �recipe� Ensure staff are properly trained and competent on the use equipment

42. ISO 9000 and Quality Most companies claim to have process recipe since most of them are now ISO certified Unfortunately most ISO 9000 documents do not even come close to defining what variables are important for yield ISO certification is a good thing but very often it is more of a marketing tool and not very helpful for building products with high yield ISO requirement: �say what you do and do what you say� as a result most companies don�t say much! Need detailed recipe to produce quality product

43. Meeting ISO but not Quality Requirements Use one profile for all products. This is OK for ISO but you really need a unique profile for each product Even an unique profile is not going to help if cause is Poor solder paste Mis-registration or misplacement of components Poor handling of components and boards Poor solderability The process document needs to address all these issues in specific detail, even though this is more than required for ISO certification

44. Training & Documentation Having the right design, good quality incoming materials and an in-house process document are necessary but not sufficient to achieve high yield on a consistent basis Training of personnel at all levels, from senior managers to engineers, operators and support staff (i.e. purchasing) is critical for addressing all the issues needed to improve yield and then profitability

45. Quality Assessment Process control is a way of life Use of statistics and process control Documented expectation and implementation Sampling plans for best practice criteria Keep operators involved in the process Develop meaningful design of experiments

46. SMT Materials & Process Specification * SMT Design For Manufacturability (DFM)* Surface Mount Equipment Characterization (IPC-9850-Not released yet) SMT Land Pattern Specification (IPC - 782) Adhesive Specification (IPC - 817) Solderability Specification (ANSI/J-Std .002/003) * Need to be developed in-house

47. Solder Fluxes (J-Std -004) Solder Paste Specification (J-Std -005) Stencil Design Guidelines (IPC 7525) Guidelines for Temperature Profiling (IPC-7530) Component Handling Series IPC-M-109 (Includes J-STD-020/33/35; and IPC-9501/02/03). Formerly IPC-786 SMT Workmanship Standard (J-Std 001/IPC-A- 610)

48. Our thanks go to IPC for providingthe base material forthis presentation