2015 Meetings

October Meeting

Agenda

Welcome/Introduction

- By Jim Wilcox

MAT1B : Reworkable Underfills On Demand

- By Pericles Kondos

REL12A : Fine Pitch Copper Pillar Interconnect for 2.5D Packaging On Demand

- By Babak Arfaei

MAT6B : Reliability of Sintered Ag Die Attach On Demand

- By Harry Schoeller

MAT7B : Pre-Aging, Surface Finish and Loading Effects on Isothermal Mechanical Behavior of Pb-free Solder Alloys On Demand

- By Francis Mutuku

MAT7EF : New Pb-free Alloys: Effect of Solder Composition, Volume and PCB Surface Finish on Reliability

On Demand

- By Babak Arfaei

REL11A : Effect of TIM Compression Loads on BGA Reliability

- By Harry Schoeller

REL6A : Solder Paste Print Correlations to Reliability

- By Michael Meilunas

0.3mm Pitch CSP Assembly - Part 2. Assembly and Reliability Results On Demand

- By Jeff Schake

APD1A : Broadband Paste Printing

- By Michael Meilunas

Hot Topics in SMT Assembly Fluxes

- By Brook Sandy-Smith

MAT8C : Conformal Coated Resistor Corrosion

- By Marie Cole

MAT8B : New Conformal Coating Materials

-By Michael Meilunas

Development of Polyurethane-based Conformal Coatings for Pb-free Electronics

-By Suraj Maganty, Junghyun Cho

MAT2A : Effect of Copper Foil Treatment on Pad Strength On Demand

-By Pericles Kondos

BGA Interconnect Stress during SMT Cooldown Simulation Study Free Package Warp Mounted Package Warp

-By Matt Schwiebert

MAT2C : High Tg PCB Laminates - Effect of Multiple Reflows on Pad Strength On Demand

-By Pericles Kondos

MAT6D : Evaluation of Component Terminations for Extended Temperature Applications On Demand

-By Harry Schoeller

MAT8B : Solid State Interfacial Reactions of Pb-free Alloys at Extended Operating Temperatures On Demand

-By Faramarz Hadian, Harry Schoeller

Effect of Ag3Sn Precipitate Morphology on the Creep Resistance of SnAgCu Solder Joints

-By Eric Cotts

June Meeting

(webinar project reports)

Effect of Cu Roughness on Pad Cratering Strength On Demand

- by Pericles Kondos

The possible effect on Cu roughness on pad strength is being investigated by using angled Hot Bump Pull to test pads on coupons made with two different laminates with copper foils of different roughness. The use of a surface treatment (primer) to improve the adhesion of the foil to the laminate complicates the interpretation of the results because it, too, can have an effect on pad strength and even on failure mode. This effect was studied by testing a smooth foil with and without primer.

High Tg PCB Laminates On Demand

- by Pericles Kondos

The first leg of the study of the effect of multiple "hot" reflows on many high-Tg laminates is nearly complete. For each laminate material, resin content and reflow history, 24 pads (from 2 different coupons) are being tested with Cold Bump Pull. This presentation focuses on a detailed discussion of a few cases rather than presenting all the available results. Of interest were not only any changes in strength due to the reflow exposure, but the magnitude of the pad strengths and how these values varied from laminate to laminate. The failure surfaces were also examined in detail.

Paste Print Correlation to Reliability On Demand

-by Michael Meilunas

Through numerous printing trials, the naturally occurring variabiility in paste deposit volumes has been identified for various printing parameters. Instances of 'outlier' low volume deposits typically flagged as printing defects were carefully noted. Such paste print 'defects' have been designed into testable assemblies at high risk solder joint locations using a custom designed stencil. CSP, LGA, SMR and QFN components are being evaluated on TB2015. Assembled boards are in thermal cycle test.

Stencil Printing Considerations for 0.3mm Pitch CSP Assembly On Demand

-by Jeff Schake

A detailed stencil printing optimization study is underway for the assembly of 0.3mm CSP components. Stencil printing factors such as aperture design (squares, circles, rotated squares), aperture size (from 140 mm to 200 mm) and printing process technology (standard squeegees, active squeegees) have been investigated. Detailed results and data analyses will be presented.

Broadband Paste Printing On Demand

-by Michael Meilunas

Complex board designs are increasingly using fine pitch components such as WLCSP in close proximity to much more massive components such as large body BGAs. This study is being defined to evaluate the limits of conventional stencil printing to position fine pitch, high resolution prints adjacent to much coarser print deposits. PCB design considerations such as label ink and top surface traces are considered. The design limitations of stepped stencils, with and without nanocoating is also included.

Progress with Pb-free Solder Alloys On Demand

- by Babak Arfaei

The AREA research portfolio includes multiple studies examining the performance of alternate lead free solder alloys under various conditions. Highlights from these various projects will be presented, including the effects of solder composition, joint volume and PCB surface finish on room temperature shear fatigue and accelerated thermal cycling performance. Additionally, the effects of processing parameters on joint microstructure and resulting mechanical behavior will be discussed. Updates on the status of current projects will be provided.

Brittle to Ductile Transition in Bi-based Solder On Demand

-by Harry Schoeller

One drawback of bismuth-based solders is the brittle nature of bismuth leading to sudden unexpected failures. However at elevated temperature, where slip is more prevalent, bismuth can dynamically recrystallize into a fine grain structure which changes the primary deformation mechanism of the solder, making it much more ductile. This work reports on the brittle to ductile transition in bismuth solder and suggests the responsible mechanism change.

Reliability of Pressureless Sintered-Ag Die Attach On Demand

-by Harry Schoeller

Sintered-Ag technology provides a Pb-free interconnection for high power/temperature applications. Previous consortium research has reported on the reliability of pressureless sintered-Ag joints with thin bondline thicknesses (<1mil). This update looks at the reliability of joints made with thicker bondline thicknesses (3-5mils) in high temperature storage and thermal shock.

March Meeting

Agenda

March AREA Introduction

- By Jim Wilcox

March AREA Introduction

- By Jim Wilcox

MAT6B : Reliability of Sintered Ag Die Attach On Demand

- By Harry Schoeller

REL6A : Paste Print Correlations to Component Reliability:Effect of Print ‘Outliers’ On Demand

- By Michael Meilunas

MAT7F : New Pb Free Alloys: Effect of Solder Composition on ATC Reliability On Demand

- By Babak Arfaei

MAT7F : Lower Melt Solder for High Reliability Electronics

Supplementary Files

- By Thilo Sack

MAT7B : Microstructural Analysis and Isothermal Mechanical Behavior of Microalloyed Pb-free Solder Alloys

On Demand

- By Francis Mutuku

MAT1A : Underfill Projects Update On Demand

- By Pericles Kondos

MAT6G : Solid State Interfacial Reactions of Pb-free Solders in High Temperature Environments On Demand

- By Harry Schoeller

REL12A : Reliability of Cu Pillar Interconnect for Next Generation 2.5D / 3D Packages On Demand

- By Babak Arfaei

REL12A : Cu Pillar Bumping on Silicon and Glass for Packaging Integration

- By Eric Perfecto

Speckle-Free Digital Image Correlation Method for in-situ Warpage Measurements

- By SB Park

APD3A : Large Body BGA Reliability On Demand

- By Harry Schoeller

MAT8B : Conformal Coating: Effects on Solder Joint Reliability On Demand

- By Michael Meilunas

REL3A : Mechanical Response of Solder Joints under Vibration Loading

- By Quang Su

REL11A : Effect of TIM Compression Loads on BGA Reliability On Demand

- By Nick Graziano

MAT2C : Pad Cratering Projects Update On Demand

- By Pericles Kondos

MAT2C : High Tg PCB Laminates: Effect of Multiple Reflows on Pad Strength On Demand

- By Pericles Kondos

APD9A : BGA Warpage: Evaluating JEDEC and JEITA Standards for Allowable Component Warpage On Demand

- By Michael Meilunas

MAT7D : Effect of Solder Composition and PCB Surface Finish on Drop Test Performance On Demand

- By Shaui Shao