Now showing items 1-10 of 10

    • Development of New No-Flow Underfill Materials for Both Eutectic Sn-Pb Solder and a High Temperature Melting Lead-Free Solder 

      Wong, C. P.; Li, Haiying; Johnson, Ashanti (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2003-06)
      In recent years, no-flow underfill technology has drawn more attention due to its potential cost-savings advantages over conventional underfill technology, and as a result several no-flow underfill materials have been ...
    • Development of Reworkable Underfill From Hybrid Composite of Free Radical Polymerization System and Epoxy Resin 

      Wong, C. P.; Fan, Lianhua (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2002-03)
      The application of the underfill encapsulant is to enhance the solder joint fatigue life in the flip chip assembly, typically up to an order of magnitude, as compared to the nonunderfilled devices. Most of the current ...
    • Double-Layer No-Flow Underfill Process for Flip-Chip Applications 

      Zhang, Zhuqing; Lu, Jicun; Wong, C. P. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2003-03)
      No-flow underfill technology shows potential advances over the conventional underfill technology toward a low-cost flop-chip underfill process. However, due to the filler entrapment in between solder bumps and contact pads ...
    • Effect of UV/Ozone Treatment on Surface Tension and Adhesion in Electronic Packaging 

      Wong, C. P.; Luo, Shijian (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2001-03)
      Surface tension of material surfaces and interfaces is an important parameter that affects wetting and adhesion. Surface tension can be divided into three components: Lifshitz–van der Waals component, acid component, ...
    • An Improved Methodology for Determining Temperature Dependent Moduli of Underfill Encapsulants 

      Wong, C. P.; Rao, Yang; Shi, Songhua (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2000-09)
      Finite element analyses (FEAs) have been widely used to preventively predict the reliability issues of flip-chip (FC) packages. The validity of the simulation results strongly depends on the inputs of the involved ...
    • Moisture Absorption in Uncured Underfill Materials 

      Wong, C. P.; Luo, Shijian (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2004-06)
      This paper presents a systematic study on moisture absorption in uncured underfill based on epoxy cured with acid anhydride [methylhexahydrophthalic anhydride (MHHPA)] and epoxy cured with non-acid anhydride curing ...
    • Novel Reworkable Fluxing Underfill for Board-Level Assembly 

      Wong, C. P.; Zhang, Zhuqing; Li, Haiying (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2004-09)
      Underfills are traditionally applied for flip-chip applications. Recently, there has been increasing use of underfill for board-level assembly including ball grid arrays (BGAs) and chip scale packages (CSPs) to enhance ...
    • Recent Advances in Flip-Chip Underfill: Materials, Process, and Reliability 

      Wong, C. P.; Zhang, Zhuqing (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2004-08)
      In order to enhance the reliability of a flip-chip on organic board package, underfill is usually used to redistribute the thermomechanical stress created by the coefficient of thermal expansion (CTE) mismatch between ...
    • Study on Effect of Coupling Agents on Underfill Material in Flip Chip Packaging 

      Wong, C. P.; Luo, Shijian (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2001-03)
      Coupling agents are widely used in order to improve the adhesion property of underfill. In this study, three different silane coupling agents, two titanate coupling agents, and one zirconate coupling agent were added ...
    • Study on Underfill/Solder Adhesion in Flip-Chip Encapsulation 

      Wong, C. P.; Fan, Lianhua; Tison, Christopher K. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2002-11)
      Underfill materials are employed in flip-chip assemblies to enhance solder joint reliability performance. The adhesion of underfills with solders is important to the integrity of the flip-chip structure. We have studied ...