Synthesis of high thermal conductivity nano-scale aluminum nitride by a new carbothermal reduction method from combustion precursor

With the development of polymer-filled composites, the demand of high thermal conductivity materials is much attractive than ever. However, the process of a common method to improve thermal conductivity of composites is considerably complicated. The aim of this study is to investigate thermal conductivity of epoxy filled silver nanoparticle deposited aluminum nitride nanoparticles with relatively convenient process. We found that the thermal conductivities of composites filled with AlN/Ag nanoparticles are effectively enhanced, which is enormously increased from 0.48 Wm-1K-1(1.88 vol%) to 3.66 Wm-1K-1 (19.54 vol%). This can be ascribed to the bridging connections of silver nanoparticle among aluminum nitride nanoparticles. In addition, the thermal contact resistance of the epoxy composites filler with AlN/Ag nanoparticles is decreased, which is proved by the fitting measured thermal conductivity of epoxy composite with one physical model. We believe the finding has great potential for any microelectronic application.

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Metallization Behavior in Aluminum Nitride Electronic Packages

MRS Proceedings ◽

10.1557/proc-203-247 ◽

1990 ◽

Vol 203 ◽

Author(s):

Ellice Y. Luh ◽

Leonard E. Dolhert ◽

Jack H. Enloe ◽

John W. Lau

Keyword(s):

Thermal Conductivity ◽

Dielectric Properties ◽

Aluminum Nitride ◽

High Density ◽

High Thermal Conductivity ◽

Electronic Packages ◽

Oxide Ceramics ◽

Chemical Behavior ◽

Hermetic Seal ◽

Silicon Based

ABSTRACTCharacteristics such as CTE close to that of silicon, high thermal conductivity, and good dielectric properties make aluminum nitride (AIN) an excellent dielectric for packaging silicon-based high density multichip interconnects. However, there remains many aspects of its behavior that have not been characterized. One such example is the behavior of the various metallizations used within a package. As with A12O3, these metallizations must contribute toward a hermetic seal separating the die from the environment. However, the chemical behavior of the metallization systems used for A12O3 may not be compatible with non-oxide ceramics such as AIN. Consequently, these chemical interactions are investigated in view of the requirements for each application within electronic packages. Hermeticity testing results are also included in the discussion.

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Highly Efficient and Low-Temperature Preparation of Plate-Like ZrB2-SiC Powders by a Molten-Salt and Microwave-Modified Boro/Carbothermal Reduction Method

Materials ◽

10.3390/ma11101811 ◽

2018 ◽

Vol 11 (10) ◽

pp. 1811 ◽

Cited By ~ 3

Author(s):

Yuan Zeng ◽

Feng Liang ◽

Jianghao Liu ◽

Jun Zhang ◽

Haijun Zhang ◽

...

Keyword(s):

Molten Salt ◽

Carbothermal Reduction ◽

Reduction Method ◽

Low Cost ◽

Highly Efficient ◽

Carbothermal Reduction Method ◽

Low Temperature Preparation ◽

Phase Pure ◽

Low Efficiency ◽

Reduced Temperature

To address the various shortcomings of a high material cost, energy-intensive temperature conditions and ultra-low efficiency of the conventional boro/carbothermal reduction method for the industrial preparation of ZrB2-SiC powders, a novel molten-salt and microwave-modified boro/carbothermal reduction method (MSM-BCTR) was developed to synthesize ZrB2-SiC powders. As a result, phase pure ZrB2-SiC powders can be obtained by firing low-cost zircon (ZrSiO4), amorphous carbon (C), and boron carbide (B4C) at a reduced temperature of 1200 °C for only 20 min. Such processing conditions are remarkably milder than not only that required for conventional boro/carbothermal reduction method to prepare phase pure ZrB2 or ZrB2-SiC powders (firing temperature of above 1500 °C and dwelling time of at least several hours), but also that even with costly active metals (e.g., Mg and Al). More importantly, the as-obtained ZrB2 particles had a single crystalline nature and well-defined plate-like morphology, which is believed to be favorable for enhancing the mechanical properties, especially toughness of their bulk counterpart. The achievement of a highly-efficient preparation of such high-quality ZrB2-SiC powders at a reduced temperature should be mainly attributed to the specific molten-salt and microwave-modified boro/carbothermal reduction method.

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Separation of Internal Strains and Lattice Distortion Caused by Oxygen Impurities in Aluminum Nitride Hot-Pressed Ceramics

Advances in X-ray Analysis ◽

10.1154/s0376030800018139 ◽

1994 ◽

Vol 38 ◽

pp. 479-487 ◽

Cited By ~ 1

Author(s):

O. N. Grigoriev ◽

S. M. Kushnerenko ◽

K. A. Plotnikov ◽

W. Kreher

Keyword(s):

Thermal Conductivity ◽

Aluminum Nitride ◽

Integrated Circuit ◽

Room Temperature ◽

Lattice Distortion ◽

High Thermal Conductivity ◽

Hybrid Integrated Circuit ◽

Oxygen Contamination ◽

Internal Strains ◽

Oxygen Impurities

Recently aluminum nitride (A1N) has been intensively studied as a promising material for production of hybrid integrated circuit substrates because of its high thermal conductivity, high fjexural strength, and nontoxic nature. The estimated theoretical value of its thermal conductivity at room temperature is 320 W/mK, but it is strongly degraded by the introduction of oxygen. The measured values vary from 30 to 260 W/mK, Therefore, in production of this material the reduction of oxygen contamination is of paramount importance.

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