Electronics underfill

Rasiah IJ, Ho PS, Manaharan M, Ng CL, Chau M. Rheological analysis of an underfill material. In Proc. 1998 lEEE/CPMT Electronics Packaging Conf. 1998 354—358. Billmeyer FW. Textbook of Polymer Scierwe. New York Interscience, Div. of John Wiley 1962 [chapter 6]. 

Anderson B, Bacher B, Gomez M. Development Methodology for a High Performance Snap-cure, Flip-chip Underfill. Dexter Electronic Materials Technical Paper Mar. 1999. Gilleo K., Blumel D. The great underfill race. In Proc. Int. Microelectronics and Packaging Soc. 1998 701-706. 

Welsh DJ, Pearson RA. Fundamental study on adhesion improvement for underfill using adhesion promoter. In Proc. 51st Electronic Components and Technol. Conf. Orlando, FL May 2001. 

Leong WH. Developing an underfill process for dense flip-chip apphcations. In Proc. 1996 lEEE/CPMT Int. Electronics Mfg. Technol Symp. Oct. 1996 10-17. lost EM, McNeiUy K, Sexton P. Silver flakes for state of the art conductive adhesive apphcations. Proc. Seventh Int. Microelectronics Conf. 1992 442-8. 

No-fiow, fiuxing type underfill Epoxy resin, substituted phthalic anhydride (81-3) and methyUiexahydrophthalic anhydride (2078E), phenolic compound, and liquid rubber component STAYCHIP 2078E and STAYCHIP 81-3 (Cookson Electronics)... 

Flip chip and CSP underfills, die-attach adhesives for advanced electronics and semiconductor packaging... 

Lim R, Duck A. Controlhng process parameters for flip-chip underfill. Electronics Engineer. Jul. 2000. 

Some adhesive materials and processes are used across many apphcations. For example, adhesives are used to attach bare die, components, and substrates in assembling commercial, consumer and aerospace electronic products. Adhesives are also widely used for surface mounting components onto interconnect substrates that serve numerous functions for both low-end consumer products and for high rehability applications. Underfill adhesives are used to provide stress relief and ruggedize the solder interconnects for almost all flip-chip and area-array devices, regardless of their function as integrated circuits. 

Alternate approaches that eUminate the capillary-flow underfill process currently used by electronics assemblers, involve pushing the problem back to the wafer stage. One process, wafer-level underfill (WLU) (Figure 5.12), consists of applying the underfill material to a bumped wafer and then B-staging the underfill. The wafer is then diced and the die are positioned on corresponding connection pads on an interconnect... 

The use of underfill adhesives has resulted in the development of the draft version of J-STD-030, Guideline for Selection and Application of Underfill Material for Flip Chip and Other Micropackages. The guideline covers critical material properties for underfill materials to assure compatibility in underfill applications for reliable electronic assemblies as well as selected process-related qualification tests such as thermal cycling. Table 6.9 summarizes selected materials requirements for underfill adhesives from the proposed JEDEC J-STD-030. ... 

Figure 2.9. Shape factors for underfill fillets. (Source Electronics Engineer, 1998.)...

Leong, W. H., Developing an Underfill Process for Dense Flip-Chip Applications, Proc. 1996 lEEE/CPMT Inti. Electronics Mfg. Technol. Symp., pp. 10-17 (Oct. 1996)... 

Compliant layer and redistribution layer (rigid) No underfill required, JEDEC MSL 1 pBGA (Tessera) Flash memory, SRAM, and DSP for portable electronics, high-reliability automotive, military, and medical applications... 

Anderson, B., Bacher, B., and Gomez, M., Development Methodology fora HighPerformance Snap-Cure, Flip-Chip Underfill, Dexter Electronic Nfaterials Technical Paper (Mar. 1999)... 

Pei-HawTsao, et a/, Underfill Characterization for low-k Dielectric/Cu Interconnect IC, Electronic... 

The synthetic route of sulfite-linked cycloaliphatic epoxy resin is presented in Figure 8.13 [38]. The synthesis of intermediate is achieved via the nucleophilic substitution reaction of thionyl chloride with cyclohex-3-enyl-1-methanol. Subsequently, Epo-S is obtained by epoxidation with OXONE oxidant. Epo-S is liquid at room temperature which is favorable for the underfilling encapsulation for high-density electronic packaging technologies such as flip chip plastic ball grid array (FC-PBGA) and MCM. 

S. Luo, T. Yamashita, C. P. Wong (2000) Study on the property of underfill based on epoxy cured with acid anhydride for flip chip application, J. Electronics Manufacturing 10, 191. 

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