Temperature Dependence of the Mechanical Properties of GaAs Wafers

1991 ◽  
Vol 113 (4) ◽  
pp. 331-336 ◽  
Author(s):  
Jun Ming Hu ◽  
Michael Pecht
Keyword(s):  
Mechanical Properties ◽  
Material Properties ◽  
Coefficient Of Thermal Expansion ◽  
Critical Value ◽  
Modulus Of Rupture ◽  
Gaas Wafer ◽  
Photovoltaic Conversion Efficiency ◽  
Die Attach ◽  
Different Temperatures ◽  
Fracture Assessment

GaAs is known to have superior electronic properties and greater photovoltaic conversion efficiency compared to elemental semiconductors such as silicon and germaniumn. Mechanical properties of GaAs at different temperatures are now necessary to incorporate into the design models for the GaAs die attach and substrate architecture for microelectronic packages. These properties are also required to aid in defining reliability and screening specifications. This paper presents the experiment results on various material properties of GaAs wafer over the temperature range of − 75°C to 200°C. Material properties determined from testing include the modulus of elasticity, the modulus of rupture, the critical value of stress intensity factor, and the coefficient of thermal expansion. The importance of fracture assessment in semiconductor devices is also discussed.

Experimental Evaluation of Mechanical Behavior of GaAs Wafer Material

1991 ◽  
Vol 226 ◽  
Author(s):  
Jun Ming Hu ◽  
Michael Pecht ◽  
Donald Barker
Keyword(s):  
Stress Intensity Factor ◽  
Thermal Expansion ◽  
Mechanical Behavior ◽  
Material Properties ◽  
Coefficient Of Thermal Expansion ◽  
Critical Value ◽  
Modulus Of Rupture ◽  
Gaas Wafer ◽  
Different Temperatures ◽  
Temperature Ranges

AbstractThe mechanical behavior of non-metalized GaAs wafer material at different temperatures were evaluated. The material properties of GaAs, including the modulus of elasticity, the modulus of rupture, the critical value of stress intensity factor, and the coefficient of thermal expansion, were experimentally determined over various temperature ranges.

scholarly journals Characterizing the Performance of Ternary Concrete Mixtures Involving Slag and Metakaolin

2020 ◽  
Vol 5 (2) ◽  
pp. 14
Author(s):  
Matthew S. Sullivan ◽  
Mi G. Chorzepa ◽  
Stephan A. Durham
Keyword(s):  
Mechanical Properties ◽  
Thermal Expansion ◽  
Fly Ash ◽  
Coefficient Of Thermal Expansion ◽  
Drying Shrinkage ◽  
Chloride Ion ◽  
Cementitious Materials ◽  
Ternary Mixtures ◽  
Modulus Of Rupture ◽  
Ternary Blends

Ternary blends of cementitious materials are investigated. A cement replacement level of 45% is used for all ternary mixtures consisting of 15% metakaolin and 30% slag replacements. Three metakaolin and two blast furnace slag, referred to as ‘slag’ for short, products commercially available are used to compare performance in ternary blends. A mixture with a 45% fly ash replacement is included to serve as a benchmark for performance. The control mixture contains 422 kg of cement per cubic meter of concrete, and a water-to-cementitious material ratio of 0.43 is used for all mixtures with varying dosages of superplasticizer to retain workability. Mixtures are tested for mechanical properties, durability, and volumetric stability. Mechanical properties include compression, split-cylinder tension, modulus of rupture, and dynamic Young’s modulus. Durability measures are comprised of rapid chloride-ion penetrability, sulfate resistance, and alkali–silica reactivity. Finally, the measure of dimensional stability is assessed by conducting drying shrinkage and coefficient of thermal expansion tests. Results indicate that ternary mixtures including metakaolin perform similarly to the control with respect to mechanical strength. It is concluded that ternary blends perform significantly better than both control and fly ash benchmark in tests measuring durability. Furthermore, shrinkage is reduced while the coefficients of thermal expansion are slightly higher than control and the benchmark.

scholarly journals The Use of Recycled Carpet in Low-Cost Composite Tooling Materials

Recycling ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 12 ◽  
Author(s):  
Kunal Mishra ◽  
Sarat Das ◽  
Ranji Vaidyanathan
Keyword(s):  
Mechanical Properties ◽  
Thermal Expansion ◽  
Material Properties ◽  
Coefficient Of Thermal Expansion ◽  
Low Cost ◽  
Value Engineering ◽  
Compressive Properties ◽  
Structural Composites ◽  
Environmental Deterioration ◽  
Composite Tooling

More than 250,000 metric tons (600 million pounds) of carpet are dumped in landfills every year. That creates a significant concern regarding environmental deterioration and economic liability. It is therefore imperative to develop sustainable post-consumer carpet-based products for high-value engineering applications such as composite tooling. To be considered as an acceptable composite tooling material, the composite needs to meet certain required properties such as a low coefficient of thermal expansion, excellent compressive properties, and high a hardness value after repeated exposure to curing cycles. The tooling composites must also exhibit the ability to endure several curing cycles, without deteriorating the mechanical properties. In the present investigation, post-consumer carpet has been recycled in the form of structural composites for tooling applications. The recycled carpet composites have been reinforced with 0.5 wt.% of graphene nanoplatelets to modify the material properties of the carpet composites. The results from compressive and hardness experiments demonstrate that the recycled carpet preserved its mechanical integrity even after several curing cycles. This indicates that recycled carpet composites have the potential to be a low-cost composite tooling alternative for the industry.

Effect of Material Properties and Thickness of Die Attach on Delamination of Die Attach/Die Paddle Interface in Electronic Package

2010 ◽  
Author(s):  
Chia-Lung Chang ◽  
Po-Hsien Li
Keyword(s):  
Material Properties ◽  
Coefficient Of Thermal Expansion ◽  
Damage Parameter ◽  
Stress And Strain ◽  
Thermal Expansion Mismatch ◽  
The Finite Element Method ◽  
Electronic Package ◽  
Die Attach ◽  
Encapsulation Process ◽  
Die Bonding

The electronic package is a multi-layered structure that is consisted of several materials. Under the temperature loadings, the interfacial stresses between layered components are generated due to the CTE (coefficient of thermal expansion) mismatch between different materials. In die bonding process, the void or defect might exist at the die attach/die paddle interface. The void cause further delamination on the interface during the encapsulation process. In this study, the finite element method is used to construct the model of electronic package with a void on the die attach/die paddle interface. The energy release rate based on J integration, which is calculated by the stress and strain around the tip of crack, is used as a damage parameter to predict the tendency of further delamination during encapsulation. Effect of material properties (Young’s modulus and CTE) and die attach thickness on delamination of die attach/die paddle interface in package during encapsulation is studied.

scholarly journals INFLUENCE OF THERMAL MODIFICATION ON THE PHYSICAL AND MECHANICAL PROPERTIES OF Eucalyptus badjensis MIXED PARTICLEBOARD / OSB PANELS

FLORESTA ◽  
2021 ◽  
Vol 51 (2) ◽  
pp. 419
Author(s):  
Giuliano Ferreira Pereira ◽  
Setsuo Iwakiri ◽  
Rosilani Trianoski ◽  
Polliana D'angelo Rios ◽  
Renan Zunta Raia
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Phenol Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Dry Mass ◽  
Thermal Modification ◽  
Modulus Of Rupture ◽  
Thickness Swelling ◽  
Swelling Properties ◽  
Different Temperatures

The objective of this research was to evaluate the effects of thermal modifications, at different temperatures and exposure times, on the technological properties of mixed particleboard / OSB panels made out of Eucalyptus badjensis. Using the wood of Eucalyptus badjensis, Particleboard, OSB and mixed Particleboard/OSB panels (control and thermally modified) were manufactured. The mixed panels’ thermal modification was carried out under three temperatures (180ºC, 200ºC and 220ºC) and two exposure times (10 minutes and 12 minutes). For the panels’ manufacturing, 6% of phenol-formaldehyde adhesive and 1% of paraffin were employed, which was calculated based on the particles’ dry mass. The water absorption and thickness swelling properties were evaluated after 2 and 24 hours of immersion, in addition to the panels’ modulus of elasticity, modulus of rupture and internal bond. Based on the results, we were able to conclude that the thermal modification affected most of the physical properties positively. From the different exposure times studied, the most effective one was the period of 12 minutes, especially for water absorption after 2 hours, which caused a reduction of 11.27%. In turn, the most effective temperature was of 220ºC, highlighting the thickness swelling after 24 hours, which caused a swelling decrease of 23.76% in comparison with the control panels. Regarding the mechanical properties, the thermal modification, in terms of the studied exposure times and temperatures, did not affect the results of the mixed particleboard /OSB panels. 

Investigation of Transfer Mold Process Effects on Semiconductor Package Warpage

2009 ◽  
Author(s):  
Jason M. Brand ◽  
Myung J. Yim ◽  
Ravi Kumar
Keyword(s):  
Solder Joint ◽  
Material Property ◽  
Material Properties ◽  
Coefficient Of Thermal Expansion ◽  
Filler Concentration ◽  
Packaging System ◽  
Property Variation ◽  
Molding Compound ◽  
Fea Model ◽  
Die Attach

In recent years, Package on Package (PoP) is increasingly used for high density package solutions. Generally the top package is a stacked memory packaging system connected to a bottom logic packaging system via solder joint: this is representative of PoP configurations. To guarantee the assembly yield and reliability of the solder joint between the top package and bottom package, mechanical compliance between these two packages is crucial during package stacking. Henceforth package warpage needs to be understood and controlled to meet the assembly yield targets. The complexity of the package configuration increases by thinner package thickness, higher number of stacking dies and large package size. Controlling the warpage within the target requirement is very challenging, especially when the material behaviors of substrate, die, molding compound and die attach film are different and also changing as a function of temperature. Certainly, the material properties of key components in top PoP package plays a crucial role in warpage performance. Among various material properties, the chemical cure shrinkage, coefficient of thermal expansion and storage modulus for the molding compounds are determining factors on the temperature dependant warpage control of top PoP package. Warpage variation still exists within parts processed at the same time mainly due to slight material property variation. In this paper, the cause of the warpage variation is investigated. The main cause was found to be filler migration effect in narrow gaps with in the stacked die package during the mold process, which resulted in different filler concentration and distribution, and finally different local molding compound material property among the package unit location in the substrate strip. The findings indicate that mold pressure is not a major modulator of warpage, while filler distribution can dramatically alter the warpage behavior. FEA model results and warpage data are presented to validate the filler migration phenomena and warpage behavior impact. The findings and results provide some clues and design/process guideline for warpage control in Top PoP package, which influence the PoP assembly yield and reliability.

Effect of Thermal Cycling on the Mechanical Properties of a Continuous Fibre Composite Used for Car Clutch Facings

2014 ◽  
Vol 891-892 ◽  
pp. 42-47 ◽  
Author(s):  
Camille Flament ◽  
Michelle Salvia ◽  
Bruno Berthel ◽  
Gerard Crosland
Keyword(s):  
Mechanical Properties ◽  
Thermal Cycling ◽  
Material Properties ◽  
Coefficient Of Thermal Expansion ◽  
Fibre Composite ◽  
Thermal Ageing ◽  
Effect Of Temperature ◽  
Full Field ◽  
Continuous Fibre ◽  
Mechanical Cycling

In dry clutch systems, the clutch facing is an annular shaped continuous fibre composite with organic matrix (thermo set resins) which transmits the torque from the engine to the wheels. In use it is submitted to thermo-mechanical cycling. Due to the composite fibre organisation, the strain field under thermo-mechanical loading is not homogenous. Full field data is needed to describe the material behaviour. Digital Image Stereo-Correlation (DISC) was used to determine the coefficient of thermal expansion (CTE) of the material. To determine the effect of temperature and cyclic loading on the mechanical properties, the composite was subjected to different thermal cycles. The material properties are modified with increasing temperature and number of cycles. These results were confirmed by dynamic mechanical analysis which showed thermal ageing of the resin. The local information given by the strain fields revealed a non uniform evolution of the material properties with thermal cycling.

Effect of Film Thickness and Cure Temperature on the Mechanical Properties of FOx® Flowable Oxide Thin Films

1999 ◽  
Vol 565 ◽  
Author(s):  
Huey-Chiang Liou ◽  
John Pretzer
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Film Thickness ◽  
Thermal Stresses ◽  
Coefficient Of Thermal Expansion ◽  
Structure Change ◽  
Curing Temperature ◽  
Different Temperatures ◽  
Cure Temperature ◽  
Different Thickness

AbstractThe mechanical properties and thermal stresses of FOx thin films at different thickness and cured at different temperatures have been investigated by a nanoindentor and a profilometer. In this study, the correlation between structure change, thickness, Si-H/Si-O ratio, modulus, hardness, and calculated coefficient of thermal expansion (CTE) of FOx films have been established. The results show that the modulus of 400°C cured FOx film decreases with increasing film thickness while the hardness slightly varies with increasing film thickness. The calculated CTE of FOx film increases with increasing film thickness. In addition, both the modulus and hardness of FOx films increase with increasing curing temperature. However, the calculated CTE of FOx film decreases with increasing curing temperature. The Si-H/Si-O ratio increases with increasing film thickness but decreases with increasing curing temperature. These results indicate that the increase in modulus and hardness and the decreases in CTE for FOx films are either due to the remaining of Si-H bonds in FOx film at different film thickness or the conversion of Si-H into Si-O when forming the network structure in the FOx film at higher curing temperatures.

Investigation of Thermomechanical Properties of Low Temperature Cofired Ceramic

1994 ◽  
Vol 116 (2) ◽  
pp. 148-153
Author(s):  
J. M. Hu ◽  
D. Barker ◽  
R. Ghoshtagore ◽  
M. Pecht
Keyword(s):  
Low Temperature ◽  
Material Properties ◽  
Coefficient Of Thermal Expansion ◽  
Thermomechanical Properties ◽  
Test Methods ◽  
Modulus Of Rupture ◽  
Multichip Modules ◽  
Electronic Packages ◽  
Ceramic Substrates ◽  
Design Models

Thermomechanical properties of low temperature cofired ceramic substrates in the range of operational temperatures are necessary to incorporate into the design models for multichip modules and other electronic packages. These properties are also required in assessing reliability and aiding in screening and qualification procedures. This paper presents the test methods and experimental results on various thermomechanical properties of low temperature cofired ceramic over the the temperature range of −55°C to +250°C. Material properties determined from the tests include the modulus of elasticity, the modulus of rupture, the fracture toughness, and the coefficient of thermal expansion.

Sign in / Sign up

Export Citation Format

Share Document