Root Cause Failure Analysis of Printed Circuit Board ... - SMTA

More documents

Recommendations

Info

Lead To Hole Clearance • Lead Lead Lead Free Free Soldering Soldering Soldering – Lead Clearance Minimum May Increase – Increasing <strong>Board</strong> Thickness May Further Increase Lead To Hole Clearance (Aspect Ratio) – Larger Holes Create Less Voids • Smaller Smaller Lead Lead To To Hole Hole Clearance Clearance Clearance Decreases Decreases Shrinkage Shrinkage Holes Holes / / Hot Hot Tear Tear Joints Joints IPC-A-610D, Fig. 5.67
Through Hole Pad Design • Square Pads Should Not Be Used On Solder Side – Increased Pad Lifting* – Increased Solder Defect – Bridge/Flag/Web • Decrease Component / Top Side Pad Size** – Reduced Fillet Lifting * Dr. S. Zweiger, Solectron GMBH, Productronica Green Day, November 2005 ** K Puttlitz, K Stalter, “Handbook <strong>of</strong> Lead-Free Solder Technology For Microelectronic Assembly”, pp 628, Fig 48
Page 1 and 2: Root Root Root Cause Cause Failure
Page 3 and 4: Today’s Electronic Designs • Co
Page 5 and 6: Component Issues - Warpage • High
Page 7 and 8: Component Issues - Decreasing Pitch
Page 9 and 10: LGA Pad Design Solder Solder Mask M
Page 11 and 12: % PAD SIZE INCREASE 60 50 40 30 20
Page 13 and 14: Component Pad - Thermal Imbalance
Page 15 and 16: Thick Copper Design A A CTE CTE Mis
Page 17 and 18: Thick Copper Design Lack Lack Of Of
Page 19 and 20: Copper Etch Process • H H = = = H
Page 21 and 22: Pad Size Reduction Current Procedur
Page 23 and 24: • Voids in Solder Joints - Unfill
Page 25 and 26: Stencil Tolerances Artwork Artwork
Page 27 and 28: Offset Paste - Normal Placement Pho
Page 29 and 30: Match Placement To Paste • Slight
Page 31 and 32: Solder Paste Printing Volume Air Bu
Page 33 and 34: Internal PCB Impacts Number Of Laye
Page 35 and 36: Wave Solder & Rework Issues 0.005
Page 37 and 38: PCB Finish Vs Solder Spread - OSP -
Page 39: Defects Caused By Improper Thermal
Page 43 and 44: Effect of Board Thickness On Topsid
Page 45 and 46: Solder Mask Selection Matte Finish
Page 47 and 48: Cleaning Chemistry Compatibility
Page 49 and 50: Inspectability - AOI, AXI, HVI •
Page 51 and 52: Cracked Cap Issue • PCA Is Assemb
Page 53 and 54: Source Of Contamination What is Sou
Page 55 and 56: DFX Software Flexibility • Concur
Page 57 and 58: DFX PCA-PCB Software Systems Mentor
Page 59 and 60: DFX Mechanical Software Systems Ana
Page 61 and 62: Closing Thought “We can’t solve

Root Cause Failure Analysis of Printed Circuit Board ... - SMTA

Create successful ePaper yourself

Delete template?

Save as template?