Structural design of multilayer thermally conductive nanofibrillated cellulose hybrid film with electrically insulating and antistatic properties

2018 ◽  
Vol 6 (26) ◽  
pp. 7085-7091 ◽  
Author(s):  
Na Song ◽  
Haidong Pan ◽  
Xiaofei Liang ◽  
Donglei Cao ◽  
Liyi Shi ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Structural Design ◽  
Heat Dissipation ◽  
Hybrid Film ◽  
Nanofibrillated Cellulose ◽  
Thermal Interface Material ◽  
Environment Friendly ◽  
Thermal Interface ◽  
Thermally Conductive

We fabricate a thermally conductive, electrically insulating and environment-friendly composite as a thermal interface material (TIM) with excellent tensile strength for heat dissipation.

Development of High Thermally Conductive Die Attach for TIM Applications

2019 ◽  
Vol 2019 (1) ◽  
pp. 000312-000315
Author(s):  
Maciej Patelka ◽  
Sho Ikeda ◽  
Koji Sasaki ◽  
Hiroki Myodo ◽  
Nortisuka Mizumura
Keyword(s):  
Thermal Conductivity ◽  
High Power ◽  
Thermal Interface Material ◽  
Thermal Interface ◽  
Power Semiconductor ◽  
Die Attach ◽  
Industry Standards ◽  
Thermally Conductive ◽  
Low Modulus ◽  
Thermal Grease

Abstract High power semiconductor applications require a Thermal Interface Die Attach Material with high thermal conductivity to efficiently release the heat generated from these devices. Current Thermal Interface Material solutions such as thermal grease, thermal pads and silicones have been industry standards, however may fall short in performance for high temperature or high-power applications. This presentation will focus on development of a cutting-edge Die Attach Solution for Thermal Interface Management, focusing on Fusion Type epoxy-based Ag adhesive with an extremally low Storage Modulus and the Thermal Conductivity reaching up to 30W/mK, and also Very Low Modulus, Low-Temperature Pressureless Sintered Silver Die Attach with the Thermal Conductivity of 70W/mK.

Characterization of Thermal Contact Resistance in Metal Micro-Textured Thermal Interface Materials Using Electrical Contact Resistance Measurements

2010 ◽  
Vol 297-301 ◽  
pp. 1190-1198 ◽  
Author(s):  
R. Kempers ◽  
A.J. Robinson ◽  
A. Lyons
Keyword(s):  
Contact Resistance ◽  
Thermal Contact Resistance ◽  
Thermal Contact ◽  
Electrical Contact ◽  
Applied Pressure ◽  
Thermal Interface Material ◽  
Metal Foil ◽  
Electrical Contact Resistance ◽  
Thermal Interface ◽  
Thermally Conductive

A novel Metal Micro-Textured Thermal Interface Material (MMT-TIM) has been developed to address a number of shortcomings in conventional TIMs. This material consists of a thin metal foil with raised micro-scale features that plastically deform under an applied pressure thereby creating a continuous, thermally conductive, path between the mating surfaces. One of the difficulties in experimentally characterizing MMT-TIMs however, is distinguishing the bulk thermal resistance of the MMT-TIM from the thermal contact resistance that exists where it contacts the test apparatus. Since these materials are highly electrically conductive, this study attempts to employ electrical contact resistance measurements to estimate their thermal contact resistance. Tests using flat silver and gold specimens of known bulk thermal conductivity were used to develop a correlation between electrical and thermal contact resistance. This relationship was then employed to estimate the thermal contact resistance of a prototype silver MMT-TIM and indicates the thermal contact resistance accounts for approximately 10% of the measured thermal contact resistance. A number of issues related to this technique are discussed as well as its future outlook.

Thermal Resistance Analysis of Sn-Bi Solder Paste Used as Thermal Interface Material for Power Electronics Applications

2014 ◽  
Vol 136 (1) ◽  
Author(s):  
Rui Zhang ◽  
Jian Cai ◽  
Qian Wang ◽  
Jingwei Li ◽  
Yang Hu ◽  
...  
Keyword(s):  
Thermal Resistance ◽  
Power Electronics ◽  
Heat Dissipation ◽  
Laser Flash ◽  
Acoustic Microscopy ◽  
Thermal Interface Material ◽  
Solder Paste ◽  
Good Reliability ◽  
Thermal Interface ◽  
Power Modules

To promote heat dissipation in power electronics, we investigated the thermal conduction performance of Sn-Bi solder paste between two Cu plates. We measured the thermal resistance of Sn-Bi solder paste used as thermal interface material (TIM) by laser flash technique, and a thermal resistance less than 5 mm2 K/W was achieved for the Sn-Bi TIM. The Sn-Bi solder also showed a good reliability in terms of thermal resistance after thermal cycling, indicating that it can be a promising candidate for the TIM used for power electronics applications. In addition, we estimated the contact thermal resistance at the interface between the Sn-Bi solder and the Cu plate with the assistance of scanning acoustic microscopy. The experimental data showed that Sn-Bi solder paste could be a promising adhesive material used to attach power modules especially with a large size on the heat sink.

Development of a Metal Micro-Textured Thermal Interface Material

2009 ◽  
Author(s):  
R. Kempers ◽  
R. Frizzell ◽  
A. Lyons ◽  
A. J. Robinson
Keyword(s):  
Thermal Conductivity ◽  
Applied Pressure ◽  
Solid Particles ◽  
High Thermal Conductivity ◽  
Thermal Interface Material ◽  
Filler Materials ◽  
Mechanical And Thermal Properties ◽  
Metal Foil ◽  
Thermal Interface ◽  
Thermally Conductive

Typical thermal interface materials (TIMs) consist of high thermal conductivity solid particles dispersed in a continuous, low thermal conductivity organic compound. Despite using filler materials of very high thermal conductivity, the effective thermal conductivity of these TIMs is often two orders of magnitude lower than the pure filler materials. In addition, dispensing and flow of the particle-matrix composite results in voids being trapped within the bond. To address these issues, a novel metal micro-textured thermal interface material (MMT-TIM) has been developed. This material consists of a thin metal foil with raised micro-scale features that plastically deform under an applied pressure thereby creating a continuous, thermally conductive, path between the mating surfaces. Numerical tools have been developed that couple the mechanical and thermal properties and behaviour of MMT-TIMs as they undergo large-plastic deformation during assembly. This study presents the modelling approach and predictions of MMT-TIM performance based on these numerical techniques. The predictions show good agreement with experimental results, which were obtained using prototype MMT-TIMs and an advanced TIM characterization facility. Finally, a future outlook for this technology is presented based on these promising initial results.

Impact of thermal interface material on luminous flux curve of InGaAlP low-power light-emitting diodes

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Muna E. Raypah ◽  
Mutharasu Devarajan ◽  
Shahrom Mahmud
Keyword(s):  
Low Power ◽  
Thermal Resistance ◽  
Thermal Management ◽  
Light Output ◽  
Luminous Flux ◽  
Thermal Interface Material ◽  
Junction Temperature ◽  
Thermal Interface ◽  
Content Type ◽  
Thermally Conductive

Purpose One major problem in the lighting industry is the thermal management of the devices. Handling of thermal resistance from solder point to the ambiance of the light-emitting diode (LED) package is linked to the external thermal management that includes a selection of the cooling mode, design of heatsink/substrate and thermal interface material (TIM). Among the significant factors that increase the light output of the of the LED system are efficient substrate and TIM. In this work, the influence of TIM on the luminous flux performance of commercial indium gallium aluminium phosphide (InGaAlP) low-power (LP) LEDs was investigated. Design/methodology/approach One batch of LEDs was mounted directly onto substrates which were glass-reinforced epoxy (FR4) and aluminium-based metal-core printed circuit boards (MCPCBs) with a dielectric layer of different thermal conductivities. Another batch of LEDs was prepared in a similar way, but a layer of TIM was embedded between the LED package and substrate. The TIMs were thermally conductive epoxy (TCE) and thermally conductive adhesive (TCA). The LED parameters were measured by using the integrated system of thermal transient tester (T3Ster) and thermal-radiometric characterization of LEDs at various input currents. Findings With the employment of TIM, the authors found that the LED’s maximum luminous flux was significantly higher than the value mentioned in the LED datasheet, and that a significant reduction in thermal resistance and junction temperature was revealed. The results showed that for a system with low thermal resistance, the maximum luminous flux appeared to occur at a higher power level. It was found that the maximum luminous flux was 24.10, 28.40 and 36.00 lm for the LEDs mounted on the FR4 and two MCPCBs, respectively. After TCA application on the LEDs, the maximum luminous flux values were 32.70, 36.60 and 37.60 lm for the FR4 and MCPCBs, respectively. Moreover, the findings demonstrated that the performance of the LED mounted on the FR4 substrate was more affected by the employment of the TIM than that of MCPCBs. Research limitations/implications One of the major problems in the lighting industry is the thermal management of the device. In many low-power LED applications, the air gap between the two solder pads is not filled up. Heat flow is restricted by the air gap leading to thermal build-up and higher thermal resistance resulting in lower maximum luminous flux. Among the significant factors that increase the light output of the LED system are efficient substrate and TIM. Practical implications The findings in this work can be used as a method to improve thermal management of LP LEDs by applying thermal interface materials that can offer more efficient and brighter LP LEDs. Using aluminium-based substrates can also offer similar benefits. Social implications Users of LP LEDs can benefit from the findings in this work. Brighter automotive lighting (signalling and backlighting) can be achieved, and better automotive lighting can offer better safety for the people on the street, especially during raining and foggy weather. User can also use a lower LED power rating to achieve similar brightness level with LED with higher power rating. Originality/value Better thermal management of commercial LP LEDs was achieved with the employment of thermal interface materials resulting in lower thermal resistance, lower junction temperature and brighter LEDs.

A review of thermal interface material fabrication method toward enhancing heat dissipation

2020 ◽  
Author(s):  
Raihana Bahru ◽  
Mohd Faiz Muaz Ahmad Zamri ◽  
Abd Halim Shamsuddin ◽  
Norazuwana Shaari ◽  
Mohd Ambri Mohamed
Keyword(s):  
Heat Dissipation ◽  
Thermal Interface Material ◽  
Fabrication Method ◽  
Thermal Interface ◽  
Material Fabrication

Silicone Gel Thermal Interface Materials for High Heat Dissipation and Thermo-Mechanical Stress Management for Good Reliability Performance

2005 ◽  
Author(s):  
J. C. Matayabas ◽  
Vassou LeBonheur
Keyword(s):  
High Performance ◽  
Heat Dissipation ◽  
High Heat ◽  
Thermal Interface Material ◽  
Market Demand ◽  
Heat Spreader ◽  
Good Reliability ◽  
Theoretical Understanding ◽  
Thermal Interface ◽  
Silicone Gel

The recent trend in microprocessor architecture has been to increase the number of transistors (higher power), shrink processor size (smaller die), and increase clock speeds (higher frequency) in order to meet the market demand for high performance microprocessors. These have resulted in the escalation of power dissipation as well as the heat flux at the silicon die level. The Intel packaging technology development group has been challenged to develop packaging solutions that not only meet the package thermal targets but also the reliability requirements. As a result, an integrated heat spreading (IHS) package was developed, comprising a Cu based heat spreader and a first level thermal interface material (TIM) between the die and the heat spreader. Due to CTE mismatches between its different elements, the IHS package is subjected to high level of thermo-mechanical stresses which lead to severe failures post reliability testing. A significant amount of theoretical understanding of thermal resistance has been developed and applied to the development of TIM formulations, and it was found that the thermo-mechanical properties of the TIM material need to be optimized to mitigate the package reliability stresses. Several material and process solutions have been investigated using fundamental approaches, and, as a result of these efforts, low stress silicone gel TIM’s were developed. This paper provides an overview of the silicone gel TIM technologies investigated at Intel, and the key learnings from the fundamental material and package integration studies.

Thermal Conductivity Enhancement in Polymer-Clay Nanocomposite Using Casting Techniques

2020 ◽  
Vol 995 ◽  
pp. 15-20
Author(s):  
Ivy Ann C. Razonado ◽  
Emee Grace T. Suarnaba ◽  
Lawrence V. Madriaga ◽  
Leslie Joy L. Diaz
Keyword(s):  
Thermal Conductivity ◽  
Heat Dissipation ◽  
Thermal Conductivity Coefficient ◽  
Unsaturated Polyester ◽  
Tape Casting ◽  
Thermal Interface Material ◽  
Thermal Interface ◽  
Conductivity Enhancement ◽  
Casting Technique ◽  
Polymer Clay Nanocomposite

Nowadays, there is a need for efficiency and miniaturization in electronic products. However, in the chip level, heat dissipation can limit the performance of these gadgets. Semiconductor industries addressed this thermal management challenge by using thermal interface material. Previous studies have shown that polymer-clay nanocomposite has an enhanced thermal conductivity which can be used as a thermal interface material. In this study, the aim was to determine the effect of casting techniques on the microstructure and thermal conductivity of the polymer-clay nanocomposites. Solution intercalation method was used in fabricating the 5vol% polymer-clay nanocomposite. Organo-modified montmorillonite (MMT) was dispersed in unsaturated polyester (UP) matrix by means of high frequency ultrasonication and formed using two casting techniques; mold casting and tape casting. Results showed a slight increase in the thermal conductivity coefficient of the tape-casted samples at 2.99 W/m-K compared to the mold-casted samples at 2.87 W/m-K. Transmission electron microscopy (TEM) and x-ray diffraction (XRD) results exhibited dispersed microstructure for both casting techniques. Polymer intercalation of ~16% increase in d-spacing of clay for mold-casted samples and with a ~20% increase in d-spacing of clay for tape-casted samples were observed. With these microstructure modifications, the increase in the thermal conductivity coefficient of the tape-casted samples can be attributed to the shear force employed by the tape casting technique.

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