Moisture absorption and diffusion in an underfill encapsulant at T > T g and T < T g

The effect of constant temperature and humidity environments on the durability of interconnects in underfilled Flip-Chip-on-Board (FCOB) assemblies is investigated in this study. Polymeric underfills, used to enhance thermomechanical durability of the interconnects, are found to create new failure modes due to hygromechanical swelling. Based on experimental observations, the failure mechanism is hypothesized to be cracking of intermetallics, which have weakened due to thermal aging. Pseudo 3-D finite element analyses are conducted to quantify the moisture absorption and diffusion through the polymeric underfill, and the resulting hygromechanical viscoplastic stress history. The simulations are combined with accelerated aging tests to assess in-service durability in hot, humid environments. Model predictions are compared with results of accelerated life tests available in the literature.

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Moisture absorption and diffusion of a carbon composite structure

Sustainable Marine Structures ◽

10.36956/sms.v1i2.116 ◽

2020 ◽

Vol 1 (2) ◽

Author(s):

Bing Wang

Keyword(s):

Composite Structure ◽

Moisture Absorption ◽

Resin Composite ◽

Moisture Diffusion ◽

Carbon Composite ◽

Fickian Diffusion ◽

Diffusion Parameters ◽

Gravimetric Data ◽

Marine Applications ◽

And Diffusion

Composite materials are lightweight structures and have been wildly used in marine applications. A carbon composite structure usually absorbs moisture while in-service, which can significantly affect its properties, and detriments the overall performance. We perform a detailed study on moisture absorption and diffusion of a carbon fibre reinforced vinyl ester resin composite system. Composite samples are immersed directly in four different solutions at a temperature of 37±0.5℃ for 1444h. The moisture diffusion is analysed through the Fickian diffusion model; the diffusion parameters are subsequently determined from the gravimetric data. The moisture absorption and interaction with the composite constituents are then discussed. These indicate the fundamentals of the moisture absorption and diffusion within the carbon composite structure.

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Effect of Moisture on Durability of Flip-Chip-on-Board (FCOB) Interconnects

10.1115/imece2000-2256 ◽

2000 ◽

Author(s):

J. H. Okura ◽

A. Dasgupta ◽

J. F. J. M. Caers

Keyword(s):

Flip Chip ◽

Failure Modes ◽

Moisture Absorption ◽

Accelerated Aging ◽

Accelerated Life Tests ◽

Accelerated Life ◽

Model Predictions ◽

Service Durability ◽

Life Tests ◽

And Diffusion

Abstract The effect of constant temperature and humidity environments on the durability of interconnects in underfilled Flip-Chip-on-Board (FCOB) assemblies is investigated in this study. Polymeric underfills, used to enhance thermomechanical durability of the interconnects, are found to create new failure modes due to hygromechanical swelling. Based on experimental observations, the failure mechanism is hypothesized to be cracking of intermetallics, which have weakened due to thermal aging. Pseudo 3-D finite element analyses are conducted to quantify the moisture absorption and diffusion through the polymeric underfill, and the resulting hygromechanical viscoplastic stress history. The simulations are combined with accelerated aging tests to assess in-service durability in hot, humid environments. Model predictions are compared with results of accelerated life tests available in the literature.

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Planarization Materials for Active Matrix Thin Film Transistor Arrays

MRS Proceedings ◽

10.1557/proc-1030-g01-07 ◽

2007 ◽

Vol 1030 ◽

Cited By ~ 1

Author(s):

Ahila Krishnamoorthy ◽

Richard Spear ◽

Amanuel Gebrebrhan ◽

Mehari Stifanos ◽

Hai Bien ◽

...

Keyword(s):

Indium Tin Oxide ◽

Moisture Absorption ◽

Flat Surface ◽

Thin Film Transistor ◽

Dielectric Films ◽

Good Adhesion ◽

Active Matrix ◽

Large Displays ◽

Uniform Liquid ◽

And Diffusion

AbstractTraditional plasma based dielectric films are conformal and cost-prohibitive for large displays. Solution based dielectrics are planarizing in nature and provide a flat surface for indium tin oxide (ITO) layer with the resultant uniform liquid crystal response throughout the pixel. In this paper, we present the display-related material properties and integration results obtained by using a solution-based organosilsesquioxane material. The material exhibits extremely high transmittance and planarization, low outgassing, high resistance to moisture absorption and diffusion, good adhesion to other layers integrated with it and ease of integration.

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Water Absorption and Diffusion in Hollow Glass Microsphere Filled Epoxy Syntactic Foams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.143-144.370 ◽

2010 ◽

Vol 143-144 ◽

pp. 370-374

Author(s):

Xiao Man Liu ◽

Chang Jun He ◽

Hui Jian Li ◽

Hai Yan Peng

Keyword(s):

Environmental Conditions ◽

Water Sorption ◽

Epoxy Resins ◽

Moisture Absorption ◽

Sorption Behavior ◽

Hollow Glass Microsphere ◽

Syntactic Foams ◽

The Subject ◽

Different Content ◽

And Diffusion

The durability is very important in the research and application of polymers and their composites under different environmental conditions. The study of durability of patical filled epoxy resins had absorpted more attension in recently years, and the study of moisture absorption or water diffusion was almost along with the material manufacture. In the present work, the water sorption behavior in a series of different content hollow particle filled syntactic foams was studied by gravimetric measurements. The fashion factors on water sorption were discussed, and the change of density of syntactic foams on the subject was put forward.

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Study on Thermal Comfort Property of Moisture Absorption and Quick Drying Apparel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.332-334.416 ◽

2011 ◽

Vol 332-334 ◽

pp. 416-419 ◽

Cited By ~ 1

Author(s):

Hong Qin Dai

Keyword(s):

Thermal Comfort ◽

High Performance ◽

Moisture Absorption ◽

Obvious Advantage ◽

Comfort Property ◽

And Diffusion

The garment materials are one of important factors of affecting thermal comfort of garment. Moisture absorption & quick dry fiber have high-performance of moisture absorption and diffusion. In the paper, the thermal comfort of garment made from moisture absorption & quick dry fiber is studied by wear trial. The subjective and objective methods were used to evaluation thermal comfort of garment. Experiment shown that Experiment shown that moisture absorption & quick dry garment can improve person’s thermal comfort while the microcliamte of garment is small. The moisture absorption & quick dry garment have no obvious advantage to improve thermal comfort of garment while person is static situation or garment size is much big.

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Meridional Circulation, Turbulence, and Diffusion Processes in Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100080477 ◽

1976 ◽

Vol 32 ◽

pp. 109-116 ◽

Cited By ~ 1

Author(s):

S. Vauclair

Keyword(s):

Convection Zone ◽

Diffusion Processes ◽

Meridional Circulation ◽

Diffusion Time ◽

Work In Progress ◽

First Results ◽

Stellar Envelopes ◽

And Diffusion ◽

Turbulence And Diffusion ◽

Hr Diagram

This paper gives the first results of a work in progress, in collaboration with G. Michaud and G. Vauclair. It is a first attempt to compute the effects of meridional circulation and turbulence on diffusion processes in stellar envelopes. Computations have been made for a 2 Mʘstar, which lies in the Am - δ Scuti region of the HR diagram.Let us recall that in Am stars diffusion cannot occur between the two outer convection zones, contrary to what was assumed by Watson (1970, 1971) and Smith (1971), since they are linked by overshooting (Latour, 1972; Toomre et al., 1975). But diffusion may occur at the bottom of the second convection zone. According to Vauclair et al. (1974), the second convection zone, due to He II ionization, disappears after a time equal to the helium diffusion time, and then diffusion may happen at the bottom of the first convection zone, so that the arguments by Watson and Smith are preserved.

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