• Journal of the Microelectronics and Packaging Society
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• v.6 no.1
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• pp.11-21
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• 1999

For microelectronic packaging application, the crystallizable glass powder in CaO-$A1_2O_3-SiO_2-B_2O_3$system was mixed with various amounts of alumina inclusions (\approx 4 $\mu \textrm{m}$), and its sintering behavior, crystallization behavior, and dielectric constant were examined in terms of vol% of alumina and the reaction between the alumina and the glass. Sintering of the CASB glass powder alone at $900^{\circ}C$ resulted in full densification (99.5%). Sintering of alumina-filled composite at $900^{\circ}C$ also resulted in a substantial denslfication higher than 97% of theoretical density, In this case, the maximum volume percent of alumina should be less than 40%. XRD analysis revealed that there was a partial dissolution of alumina into the glass. This alumina dissolution, however, did not show the particle growth and shape accommodation. Therefore, the sintering of both the pure glans and the alumina-filled composite was mainly achieved by the viscous flow and the redistribution of the glass. Alumina dissolution accelerated the crystallization initiation time at $1000^{\circ}C$ and hindered the densification of the glass. Dielectric constants of both the alumina-filled glass and the glass-ceramic composites were increased with increasing alumina content and followed rule of mixture. In case of the glass-ceramic matrix composites showed relatively lower dielectric constant than the glass matrix composite. Furthermore, as alumina content increased, crystallization behavior of the glass was changed due to the reaction between the glass and the alumina. As alumina reacted with the glass matrix, the major crystallized phase was shifted from wollastonite to gehlenite. In this system, alumina dissolution strongly depended on the particle size: When the particle size of alumina was increased to 15 $\mu\textrm{m}$, no sign of dissolution was observed and the major crystallized phase was wollastonite.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.131-134
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• 2000

Increased temperature adversely affects the reliability of a device. So, package material should have high thermal diffusion, i.e., high thermal conductivity. And, there are several other physical properties of polymeric materials that are important to microelectronics packaging, some of which are a low dielectric constant, a low coefficient of thermal expansion (CTE), and a high flexural strength. In this study, to get practical maximum packing fraction of AIN (granular type) filled EMC, the properties such as the spiral flow, thermal conductivity, CTE, and water resistance of AIN-filled EMC (65-vol%) were evaluated according to the size of AIN and the filler-size distribution. Also, physical properties of AIN filled EMC above 65-vol% were evaluated according to increasing AIN content at the point of maximum packing fraction (highly loading condition). The high loading conditions of EMC were set $D_L/D_S$=12 and $X_S$=0.25 like as filler of sphere shape and the AIN filled EMC in this conditions can be obtained satisfactory fluidity up to 70-vol%. As a result, the AIN filled EMC (70-vol%) at high loading condition showed improved thermal conductivity (about 6 W/m-K), dielectric constant (2.0~3.0), CTE(less than 14 ppm/$^{\circ}C$) and water resistance. So, the AIN filled EMC (70-vol%) at high loading condition meets the requirement fur advanced microelectronic packaging materials.

• Transactions on Electrical and Electronic Materials
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• v.17 no.5
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• pp.280-288
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• 2016

Microelectronic product consumers may already be expecting another paradigm shift with smarter phones over smart phones, but the current status of microelectronic manufacturing engineering education (MMEE) in universities hardly makes up the pace for such a fast moving technology paradigm shift. The purpose of MMEE is to educate four-year university graduates to work in the microelectronics industry with up-to-date knowledge and self-motivation. In this paper, we present a comprehensive curriculum for a four-year university degree program in the area of microelectronics manufacturing. Three hands-on experienced-based courses are proposed, along with a methodology for undergraduate students to acquire hands-on experience, towards integrated circuits (ICs) design, fabrication and packaging, are presented in consideration of manufacturing engineering education. Semiconductor device and circuit design course for junior level is designed to cover how designed circuits progress to micro-fabrication by practicing full customization of the layout of digital circuits. Hands-on experienced-based semiconductor fabrication courses are composed to enhance students’ motivation to participate in self-motivated semiconductor fab activities by performing a series of collaborations. Finally, the Microelectronics Packaging course provides greater possibilities of mastered skillsets in the area of microelectronics manufacturing with the fabrication of printed circuit boards (PCBs) and board level assembly for microprocessor applications. The evaluation of the presented comprehensive curriculum was performed with a students’ survey. All the students responded with “Strongly Agree” or “Agree” for the manufacturing related courses. Through the development and application of the presented curriculum for the past six years, we are convinced that students’ confidence in obtaining their desired jobs or choosing higher degrees in the area of microelectronics manufacturing was increased. We confirmed that the hypothesis on the inclusion of handson experience-based courses for MMEE is beneficial to enhancing the motivation for learning.

• Journal of Powder Materials
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• v.13 no.5 s.58
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• pp.321-326
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• 2006

Electronic packaging involves interconnecting, powering, protecting, and cooling of semiconductor circuits fur the use in a variety of microelectronic applications. For microelectronic circuits, the main type of failure is thermal fatigue, owing to the different thermal expansion coefficients of semiconductor chips and packaging materials. Therefore, the search for matched coefficients of thermal expansion (CTE) of packaging materials in combination with a high thermal conductivity is the main task for developments of heat sink materials electronics, and good mechanical properties are also required. The aim of this work is to develop copper matrix composites reinforced with carbon nanofibers. The advantages of carbon nanofibers, especially the good thermal conductivity, are utlized to obtain a composite material having a thermal conductivity higher than 400 W/mK. The main challenge is to obtain a homogeneous dispersion of carbon nanofibers in copper. In this paper, a technology for obtaining a homogeneous mixture of copper and nanofibers will be presented and the microstructure and properties of consolidated samples will be discussed. In order to improve the bonding strength between copper and nanofibers, different alloying elements were added. The microstructure and the properties will be presented and the influence of interface modification will be discussed.

• Journal of the Microelectronics and Packaging Society
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• v.7 no.3
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• pp.37-44
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• 2000

The corrosion behavior of aluminum pad coated with epoxy molding compound (EMC) was investigated using electrochemical impedance spectroscopy (EIS). The impedance change was evaluated by the absorption of deionized water (DI water) to EMC coating and the interface between EMC and aluminum. During the absorption a decrease in resistance and thus an increase in capacitance of EMC as well as the interface of EMC/Al could be observed. Up to about 170 hours of absorption the EMC was saturated with the water molecules and ions generated from EMC. Subsequently the ionic water was penetrated to the interface and finally the corrosion of aluminum was occurred by the Dl water and ions. From measuring the adhesion strength with the Dl water absorption it was expected that the saturation of water and ions in the interface decreased the adhesion strength. The higher filler content of EMC should be necessary to inhibit the corrosion of aluminum electrode in microelectronic packages.

• Journal of Astronomy and Space Sciences
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• v.13 no.1
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• pp.40-47
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• 1996

One of the important effects of the space environment on the satellites and spacecrafts is the single event upsets (SEUs) which are caused by the high energy particles in space. A SEU occurs when an ionizing radiation produces a burst of electron-hole pairs in a digital microelectronic circuit and causes the charge state to change. We have developed and integrated a software package which can estimate the SEU rates for any specified locations or altitudes under various geophysical conditions. We report in this paper the algorithm of the software and the results for some devices with known parameters. We also compare the results with actual observations made by Akebono.

• Polymer Science and Technology
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• v.3 no.1
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• pp.36-43
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• 1992

Trifluoromethyl group을 내열성고분자의 주쇄에 도입하면 내열성의 큰 손실없이 용해도의 증가 및 유전상수의 감소등 절연재료로서의 성능을 향상시켜 주지만, 유연한기의 도입에 따른 $T_g$의 저하등 부정적인 효과도 나타낸다. 분자구조설계에 의해 기존 고분자재료의 성능을 향상시키려는 시도는 흔히 향상되어지는 성질들에 반비례하여 어는 다른 성질의 저하를 초래하는 경향이 있으나, 유전상수나 가공성 이외에도 낮은 열팽창계수를 갖는 polyimides, 열경화성수지인 poly(benzocyclobutene) 등의 packaging 재료로서의 개발등, 낮은 절연율, 내열성, 가공성, 접착력, 적절한 열팽창계수 및 기계적 성질 등 가능한 모든 필요성질을 동시에 최대한 만족시키는 고분자재료에 대한 개발노력이 계속되어지고 있으며 장차 혁신적인 새로운 고분자 재료의 등장도 이루어지리라고 본다.

• Journal of the Microelectronics and Packaging Society
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• v.9 no.2
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• pp.55-60
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• 2002

The recent trend in electronic devices has been towards light weight, low cost, high performance and improved reliability. Passive components are very important parts of microelectronic devices. The number of passive components used in hand held devices and computers continue to increase. To achieve improvements in costs, component density, performance, and reliability, embedding of these passive components into the printed circuit boards (PCBs) is required. This paper introduces the embedding of passive components, and discusses the remained challenges in the commercialization of this technique.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.3
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• pp.1-7
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• 2012

Electroplating technology is widely used in semiconductor microelectronic industry. With the development of semiconductor integrated circuit to high density and light-small scale, Extremely high quality and plated uniformity of the deposited metals are needed. Simulation technique can help to obtain better plating results. Although a few plating simulation softwares have been commercialized, plating simulation is not widely prevalent in Korea. In this paper, principle of electroplating and mathematical modeling of plating simulation are discussed. Also introduced are some cases enhancing plating thickness uniformity on leadframe, PCB and wafer by using plating simulation.

• Korean Journal of Materials Research
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• v.26 no.8
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• pp.427-429
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• 2016

A multi-step deposition process for the gap-filling of submicrometer trenches using dimethyldimethoxysilane (DMDMOS), $(CH_3)_2Si(OCH_3)_2$, and $C_xH_yO_z$ by plasma enhanced chemical vapor deposition (PECVD) is presented. The multi-step process consisted of pre-treatment, deposition, and post-treatment in each deposition step. We obtained low-k films with superior gap-filling properties on the trench patterns without voids or delamination. The newly developed technique for the gap-filling of submicrometer features will have a great impact on inter metal dielectric (IMD) and shallow trench isolation (STI) processes for the next generation of microelectronic devices. Moreover, this bottom up gap-fill mode is expected to be universally for other chemical vapor deposition systems.