Now showing items 1-20 of 61

    • Adhesion Evaluation on Low-Cost Alternatives to Thermosetting Epoxy Encapsulants 

      Wong, C. P.; Fan, Lianhua (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2003-04)
      The thermosetting epoxy curing systems have been widely used as encapsulants in the electronic packaging industry. With the continual evolving of electronic product markets, material suppliers have been challenged to ...
    • Assembly of Lead-free Bumped Flip-Chip with No-Flow Underfills 

      Wong, C. P.; Zhang, Zhuqing (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2002-04)
      Lead-free solder reflow process has presented challenges to no-flow underfill material and assembly. The currently available no-flow underfill materials are mainly designed for eutectic Sn–Pb solders. This paper presents ...
    • Chemical and Mechanical Adhesion Mechanisms of Sputter-Deposited Metal on Epoxy Dielectric for High Density Interconnect Printed Circuit Boards 

      Wong, C. P.; Martin, Lara J. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2001-09)
      Strong chemical reactions between metal and polymer substrates significantly enhance adhesion of the metal to the polymer. This study investigated the adhesion of three types of thin film metals, including Cu, NiCr, and ...
    • Comparative Study of Thermally Conductive Fillers for Use in Liquid Encapsulants for Electronic Packaging 

      Wong, C. P.; Bollampally, Raja Sheker (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 1999-02)
      Thermal management plays a very vital role in the packaging of high performance electronic devices. Effective heat dissipation is crucial to enhance the performance and reliability of the packaged devices. Liquid ...
    • Conductivity Mechanisms of Isotropic Conductive Adhesives (ICA’s) 

      Wong, C. P.; Lu, Daoqiang; Tong, Quinn K. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 1999-07)
      Isotropic conductive adhesives (ICA’s) are usually composites of adhesive resins with conductive fillers (mainly silver flakes). The adhesive pastes before cure usually have low electrical conductivity. The conductive ...
    • Conformal Magnetic Composite RFID for Wearable RF and Bio-Monitoring Applications 

      Yang, Li; Martin, Lara J.; Staiculescu, Daniela; Wong, C. P.; Tentzeris, Manos M. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2008-12-12)
      This paper introduces for the first time a novel flexible magnetic composite material for RF identification (RFID) and wearable RF antennas. First, one conformal RFID tag working at 480 MHz is designed and fabricated as a ...
    • Correlation of Flip Chip Underfill Process Parameters and Material Properties with In-Process Stress Generation 

      Wong, C. P.; Palaniappan, Prema; Baldwin, Daniel F.; Selman, Paul J.; Wu, Jiali (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 1999-01)
      Electronic packaging designs are moving toward fewer levels of packaging to enable miniaturization and to increase performance of electronic products. One such package design is flip chip on board (FCOB). In this method, ...
    • Development of Conductive Adhesives for Solder Replacement 

      Wong, C. P.; Lu, Daoqiang (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2000-12)
      With the phasing out of lead-bearing solders, electrically conductive adhesives (ECAs) have been identified as an environmentally friendly alternative to tin/lead (Sn/Pb) solders in electronics packaging applications. ...
    • Development of Environmental Friendly Non-Anhydride No-Flow Underfills 

      Wong, C. P.; Zhang, Zhuqing; Fan, Lianhua (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2002-03)
      Most no-flow underfill materials are based on poxy/anhydride chemistry. Due to the sensitizing nature, the use of anhydride is limited and there is a need for a no-flow underfill using nonanhydride curing system. This ...
    • Development of High Performance Interfill Materials for System Chips Technology 

      Wong, C. P.; Wu, Jiali; Bhattacharya, Swapan; Lloyd, Courtney; Pogge, H. Bernhard; Tummala, Rao R. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2002-06)
      An innovative precisely interconnected chip (PIC) technology is currently under development at IBM to seek more effective means of creating system chips. The objective of this research is developing fabrication methods to ...
    • Development of New Low Stress Epoxies for MEMS Device Encapsulation 

      Wong, C. P.; Wu, Jiali (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2002-06)
      In this study, a series of new low stress epoxies was introduced as conformal encapsulants, which show a high promise to meet all the requirements for the protection of the pressure sensor system. Mechanical properties ...
    • 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 No-Flow Underfill Materials for Lead-Free Solder Bumped Flip-Chip Applications 

      Wong, C. P.; Zhang, Zhuqing; Shi, Songhua (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2001-03)
      No-flow underfill process in flip-chip assembly has become a promising technology toward a smaller, faster and more cost-efficient packaging technology. The current available no-flow underfill materials are mainly ...
    • 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 Materials and Process 

      Wong, C. P.; Zhang, Zhuqing (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2003-05)
      The no-flow underfill has been invented and practiced in the industry for a few years. However, due to the interfering of silica fillers with solder joint formation, most no-flow underfills are not filled with silica ...
    • 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 Permittivity and Permeability of a Flexible Magnetic Composite Material on the Performance and Miniaturization Capability of Planar Antennas for RFID and Wearable Wireless Applications 

      Martin, Lara J.; Ooi, Sooliam; Staiculescu, Daniela; Hill, Michael D.; Wong, C. P.; Tentzeris, Manos M. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., 2009-12)
      This paper is an investigation of the feasibility of applying a mechanically flexible magnetic composite material to radio frequency identification (RFID) planar antennas operating in the lower ultrahigh-frequency (UHF) ...
    • 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, ...
    • Effective Elastic Modulus of Underfill Material for Flip-Chip Applications 

      Wong, C. P.; Qu, Jianmin (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2000-03)
      In this paper, a micromechanics model based on the Mori–Tanaka method was developed to estimate the elastic modulus of underfill materials. An explicit expression of the underfill modulus was derived as a function of filler ...
    • Electrical Property Improvement of Electrically Conductive Adhesives Through In-Situ Replacement by Short-Chain Difunctional Acids 

      Wong, C. P.; Li, Yi; Moon, Kyoung-Sik (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, Inc., New York, 2006-03)
      To improve the electrical properties of electrically conductive adhesives (ECAs), short-chain difunctional acids, such as malonic acid (acid M), adipic acid (acid A), and terephthalic acid (acid T) were introduced into a ...