에폭시 수지에 따른 언더필의 특성에 관한 연구

노보인,이종범,정승부,Noh, Bo-In,Lee, Jong-Bum,Jung, Seung-Boo 한국마이크로전자및패키징학회 2006 마이크로전자 및 패키징학회지 Vol.13 No.3

다양한 에폭시 수지를 함유한 언더필의 열적 특성을 시차주사열량측정법, 열중량측정법, 동적-기계적 분석법, 열적-기계적 분석법과 같은 열 분석법을 이용하여 분석하였다. 또한, 언더필과 FR-4기판 사이의 접합 강도를 측정하였다. Cycolaliphatic 에폭시 수지를 함유한 언더필의 유리 전이 온도가 cycolaliphatic 에폭시 수지를 함유하지 않은 언더필의 유리 전이 온도보다 낮음을 확인할 수 있다. 대기로부터 유입된 산소와 열화된 폴리머 사이의 화학적 반응으로 인하여 언더필의 열적 감소 반응이 두 번 발생하는 것을 확인할 수 있다. Cycolaliphatic 에폭시 수지를 함유한 언더필의 열팽창 계수가 cycolaliphatic 에폭시 수지를 함유하지 않은 언더필의 열팽창 계수보다 높음을 확인할 수 있다. 과도한 경화 온도는 에폭시 수지의 경계면을 약하게 하여 에폭시 수지의 기계적 특성의 변화를 초래하게 되고 언더필과 FR-4 기판 사이의 접합 특성을 저하시키게 된다. This study was investigated the thermal properties of underfill with various epoxy resins using thermal analysis methods such as differential scanning calorimetry (DSC), thermo gravimetry analysis (TGA), dynamic mechanical analysis (DMA) and thermo-mechanical analysis (TMA). And, the adhesion strength of the underfills/FR-4 substrate was evaluated. The glass transition temperature (Tg) of underfill which was composed the cycolaliphatic epoxy resin was lower than that of underfill which was not composed the cycolaliphatic epoxy resin. The thermal degradation of underfill was composed of two processes, which involved chemical reactions between the degrading polymer and oxygen from the air atmosphere. The coefficient of thermal expansion (CTE) of underfill which was composed the cycolaliphatic epoxy resin was higher than that of underfill which was not composed the cycolaliphatic epoxy resin. The excessive curing temperatures caused a weak boundary layer of epoxy resin, which resulted in a deterioration of mechanical properties in the epoxy resin and thus led to poor adhesion property between the underfill/FR-4 substrate.

무연 Sn-Bi-Ga-Zn계 솔더의 특성에 관한 연구

노보인,이보영 한국 항공대학교 항공산업기술연구소 2000 航空宇宙産業技術硏究所 硏究誌 Vol.10 No.-

The object of this study is to estimate Sn-Bi-Ga-Zn solder alloy as a substitute for Sn-37wt%Pb alloy. For Sn-Bi-Ga-Zn alloys, Bi, Ga and Zn contents are varied. (Bi : 3∼7%, Ga 1∼3%, Zn 1∼5%) Comparing with Sn-37wt%Pb alloy, Sn-Bi-Ga-Zn alloys have wider melting temperature range up to max. 46.7℃. With increasing Bi, Ga contents, the wettability of the alloys increased but with increasing Zn contents, the wettability of the alloys decreased. With increasing Bi, Ga contents, the vickers hardness of the alloys increased but with increasing Zn contents, the vickers hardness of the alloys decreased. The lickers hardness of the alloys was max. 39.1 Hv. The ultimate tensile stress of the alloys was measured to be max. 83.4 MPa and the elongation max. 6.0 %.

BGA 패키지를 위한 언더필의 열적 특성과 유동성에 관한 연구

노보인,이보영,김수종,정승부,Noh, Bo-In,Lee, Bo-Young,Kim, Soo-Jung,Jung, Seung-Boo 대한용접접합학회 2006 대한용접·접합학회지 Vol.24 No.2

In this study, the curing kinetics and thermal degradation of underfill were investigated using differential scanning calorimetry (DSC) and thermo gravimetry analysis (TGA). The mechanical and thermal properties of underfill were characterized using dynamic mechanical analysis (DMA) and thermo-mechanical analysis (TMA). Also, we presented on underfill dispensing process using Prostar tool. The non-isothermal DSC scans at various heating rates, the exothermic reaction peak became narrower with increasing the heating rate. The thermal degradation of underfill was composed of two processes, which involved chemical reactions between the degrading polymer and oxygen from the air atmosphere. The results of fluidity phenomena were simulated using Star CD program, the fluidity of the underfills with lower viscosity was faster.

Effect of Atmospheric-Pressure Plasma Treatment on the Adhesion Characteristics of a Flexible Copper Clad Laminate

노보인,Jung-Rae Jo,정승부 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.3

In this study, the effect of atmospheric-pressure plasma treatment on the adhesion strength between the polyimide and the adhesive layer of a flexible copper clad laminate (FCCL) was evaluated using 90-deg peel testing. The changes in the chemical bonding and the surface morphology after plasma treatment and the failure mode after the peel test were characterized by using X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and scanning electron microscopy (SEM). The atmospheric-pressure plasma treatment on the polyimide increased the oxygen-containing functional groups, thereby improving the adhesion characteristics between the polyimide and the adhesive layer. The FCCL with a polyimide surface having a higher root-mean square (RMS) roughness had a higher adhesion strength than that having a lower RMS roughness. Failures of the FCCLs with higher and lower adhesion strength occurred in the polyimide and at the interface between the polyimide and the adhesive layer, respectively.

Effect of Ni-Cr Seed Layer Thickness on the Adhesion Characteristics of Flexible Copper Clad Laminates Fabricated using a Roll-to-Roll Process

노보인,윤정원,정승부 대한금속·재료학회 2010 METALS AND MATERIALS International Vol.16 No.5

The adhesion strength of a Cu/Ni-Cr/polyimide flexible copper clad laminate (FCCL), which was manufactured via a roll-to-roll process, was evaluated according to the thickness of the Ni-Cr seed layer using a 90° peel test. The changes in the morphology, chemical bonding, and adhesion properties were characterized using a scanning electron microscopy (SEM), an atomic force microscopy (AFM), and an X-ray photoelectron spectroscopy (XPS). The thickness of the Ni-Cr (Ni:Cr = 80:20) seed layer in which the maximum peel strength of the FCCL was observed was 200Å. The higher FCCL peel strength was attributed to the lower proportion of C-N bonds and higher proportion of C-O and carbonyl (C = O) bonds in the polyimide surface compared with the FCCL with a lower adhesion strength. The FCCL with a higher peel strength had a fractured polyimide surface with a higher surface roughness. The adhesion strength between the metal and polyimide was pirmarily attributed to the chemical interaction between the metal layer and the functional groups of the polyimide.

Sn-0.7wt%Cu-Xwt%Re 솔더의 특성에 관한 연구

노보인,원성호,정승부,Noh, Bo-In,Won, Sung-Ho,Jung, Seung-Boo 한국마이크로전자및패키징학회 2007 마이크로전자 및 패키징학회지 Vol.14 No.4

In this study, the properties of Sn-0.7wt%Cu-Xwt%Re(X=$0.01{\sim}1.0$) older were investigated by using DSC(differential scanning calorimetry), wetting balance, victors hardness and tensile testers. The melting temperature of solder was increased with increasing the contents of rare earth element, and the melting temperature range of Sn-0.7Cu-($0.01{\sim}1.0$)Re solder was $233.9{\sim}234.7^{\circ}C$. The wettability with Sn-0.7Cu-0.1Re solder was higher than that of Sn-0.7Cu-0.01Re and Sn-0.7Cu-1.0Re solders, and the wettability of Sn-0.7Cu-0.1Re solder was higher than that of Sn-0.7wt%Cu-0.01w%P solder. Also, the hardness and tensile strength of solder were increased with increasing the contents of rare earth element. 본 연구에서는 시차주사열량법, 젖음성 시험기, 비커스 경도계와 인장 시험기를 이용하여 Sn-0.7wt%Cu-Xwt%Re(X=$0.01{\sim}1.0$) 솔더의 특성에 관하여 평가하였다. 희토류 금속의 함량이 증가함에 따라 솔더의 용융 온도가 약간 상승하는 경향을 나타내었으나 $0.01{\sim}1.0%$의 희토류 금속이 첨가된 범위에서는 $233.9{\sim}234.7^{\circ}C$의 작은 용융 온도 범위를 갖는 것을 확인할 수 있었다. 솔더의 젖음성 시험 결과로부터 Sn-0.7Cu-0.1Re 솔더의 젖음성이 다른 솔더보다 우수한 것을 확인할 수 있었으며, Sn-0.7Cu-0.1Re 솔더의 젖음성이 Sn-0.7wt%Cu-0.01wt%P 솔더보다 우수한 것을 확인할 수 있었다. 또한 희토류 금속의 함량이 증가할수록 솔더의 경도와 인장 강도가 증가하는 경향을 확인할 수 있었다.

비전도성 접착제가 사용된 플립칩 패키지의 신뢰성에 관한 연구

노보인,이종범,원성호,정승부,Noh, Bo-In,Lee, Jong-Bum,Won, Sung-Ho,Jung, Seung-Boo 한국마이크로전자및패키징학회 2007 마이크로전자 및 패키징학회지 Vol.14 No.4

본 연구에서는 가속화 조건에서의 비전도성 접착제가 사용된 플립칩 패키지의 열적 신뢰성에 관하여 평가하였다. 실리콘 칩에 $17{\mu}m$두께의 Au 범프를 형성하고 무전해 Ni/Au 도금과 Cu 패드의 두께가 각각 $5{\mu}m$와 $25{\mu}m$로 형성된 연성 기판을 사용하여 플립칩 패키지를 형성하였다. 유리전이온도가 $72^{\circ}C$인 비전도성 접착제를 사용하여 플립칩을 접합시킨 후 열충격 시험과 항온항습 시험을 실시하였다. 열충격 싸이클과 항온항습 유지 시간이 증가할수록 플립칩 패키지의 전기 저항이 증가하는 것을 확인할 수 있었다. 이는 Au 범프와 Au 범프 사이의 균열, 칩과 비전도성 접착제 또는 기판과 비전도성 접착제 사이의 층간 분리에 의한 것으로 사료된다. 또한 항온항습 하에서의 전기 저항의 변화가 열충격하에서 보다 큰 것을 확인할 수 있었다. 따라서 비전도성 접착제가 사용된 플립칩 패키지는 온도보다 습기에 더욱 민감하다는 것을 알 수 있었다. In this study, the thermal reliability on flip chip package with non-conductive pastes (NCPs) was evaluated under accelerated conditions. As the number of thermal shock cycle and the dwell time of temperature and humidity condition increased, the electrical resistance of the flip chip package with NCPs increased. These phenomenon was occurred by the crack between Au bump and Au bump and the delamination between chip or substrate and NCPs during the thermal shock and temperature and humidity tests. And the variation of electrical resistance during temperature and humidity test was larger than that during thermal shock test. Therefore it was identified that the flip chip package with NCPs was sensitive to environment with moisture.

무연 Sn-Ag-Bi-Ga계 솔더의 특성에 관한 연구

노보인,이보영 대한용접접합학회 2000 대한용접·접합학회지 Vol.18 No.6

The object of this study is to estimate Sn-Ag-Bi-Ga solder alloy as a substitute for Sn-37Pb alloy. For Sn-Ag-Bi-Ga alloys, Ag, Bi and Ga contents are varied. (Ag : 1~5%, Ga : 3%, Bi : 3~6%) Comparing to Sn-37Pb alloy Sn-Ag-Bi-Ga alloys have wider melting temperature range up to max. $18.7^{\circ}C$. With increasing Ag, Bi contents, the wettability of the alloys increased up to max. 6.6 mN. The vickers hardness of the alloys was max. 46.4 Hv. The ultimate tensile stress of the alloys was max. 60.3 MPa and the elongation was max. 1.2%. The joint strength between circuit board and solder was max. 55.5 N and the joint strength between connector and solder was max. 176.1 N. There were no cracks in this alloys after thermal shock test.

Sn-Xwt%Cu계 솔더의 젖음성에 관한 연구

노보인,윤정원,정승부,Noh, Bo-In,Yoon, Jeong-Won,Vu, Bui Quoc,Jung, Seung-Boo 대한용접접합학회 2007 대한용접·접합학회지 Vol.25 No.6

The wettability of Sn-Xwt%Cu(X=$0{\sim}3wt%$) solder was evaluated with wetting balance tester. And, the intermetallic compounds(IMCs) which were formed at the interface between solders and pads were investigated by using scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS). The wetting force of Sn-0.7wt%Cu solder was higher than that of 100wt%Sn and Sn-3.0wt%Cu solder. The value of $\gamma_{fl}$ and ($\gamma_{fs}-\gamma_{ls}$) had a tendency to increase with increasing the wetting temperature. The activation energy with bare Cu pad and flux with 15% solid content was increased in the following order: Sn-0.7Cu (68.42 kJ/mol) ; Sn-3.0Cu(72.66 kJ/mol) ; Sn solder(94.53 kJ/mol). It was identified that the Cu6Sn5 phase was formed at the interface between Sn-Xwt%Cu solder and Cu pad.

유아의 디지털 미디어 사용유형에 따른 초기 문해의 차이와 어머니 문해지도 및 디지털 리터러시 태도의 영향력

노보람(No, Bo-Ram) 한국열린유아교육학회 2022 열린유아교육연구 Vol.27 No.3

본 연구는 유아의 디지털 미디어 사용유형을 발견하고, 이에 따른 유아의 초기 문해(문해 흥미, 문해 능력) 차이와 유형화에 대한 어머니 요인(문해지도, 디지털 리터러시 태도)의 영향력을 밝히고자 하였다. 만 5세 반에 재원 중인 유아와 어머니 102쌍을 대상으로, 유아는 초기 문해 검사, 어머니는 질문지 조사에 참여하였다. 자료의 분석을 위해 잠재계층분석, 일원변량분석, 그리고 다항로지스틱 회귀분석을 실시하였다. 잠재계층분석 결과, 유아의 디지털 미디어 사용은 유아 콘텐츠 활용형, 다방면 활용형, 제한적 활용형 세 집단으로 구분되었다. 일원변량분석 결과, 다방면 활용형이 읽기와 쓰기 흥미가 높았지만, 집단 간 문해 능력 차이는 없었다. 다항로지스틱 회귀분석 결과, 어머니 문해지도 중 발현적 지도와 디지털 지도, 어머니 디지털 리터러시 태도 중 자기효능감과 자기조절이 유형의 소속에 영향을 미쳤다. 본 연구는 유아기 디지털 미디어 사용이 질적으로 다른 유형으로 구분되며, 유형 구분에 대한 어머니 요인의 영향력을 밝힘으로써 유아기 디지털 미디어 사용에 대한 함의를 제공하였다. This study investigated the types of digital media usage of young children and compared the level of their literacy interest and early literacy ability by the type of digital media usage. The study also identified the influence of factors related to the mother such as belief and guidance styles on literacy practice and digital literacy attitude on different types. Participants were 102 children and their mothers. A latent class analysis, one-way ANOVA, and multiple logistic regression were conducted. Major findings were as follows. First, the latent classes of early childhood digital media usage were classified into three types: Early childhood education contents, intense, and limited user groups. Second, young children of the intense user group were more likely to have reading interest and writing interest than those of the other groups. Third, the following predictors jointly predicted latent classes of early childhood digital media usage: Mother’s belief and guidance styles on literacy practice (emergent literacy practice, digital literacy practice) and mother’s digital literacy attitude (self-efficacy, self-regulation). Based on the results, implications for digital media usage of young children were also discussed.