• The Journal of the Convergence on Culture Technology
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• v.4 no.3
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• pp.209-212
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• 2018

Anisotropic conductive film(ACF) bonding is widely used for making fine interconnections between two different materials where soldering is not easily applicable. There are three constraints for the successful implementation of ACF bonding. A bonding contact should be pressed by a hot head with the right pressure and temperature for a pre-defined curing time. In this paper, a method for ACF bonding based on machine vision system is proposed and verified through some experiments. The system calculates the position and orientation of printed circuit boards(PCBs) on a bonding table and estimates the optimal hitting point where the hot head should be applied. Experimental results show that the proposed system achieves better adhesive strength by providing head flatness over contact surfaces.

• Journal of the Microelectronics and Packaging Society
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• v.16 no.1
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• pp.27-31
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• 2009

In this paper, the polymer adhesive bonding technology using wafer-level technology was investigated and warpage results were analyzed. Si and glass wafer was bonded after adhesive polymer layer and dam pattern for uniform state was patterned on glass wafer. In this study, warpage result decreased as the low of bonding temperature of Si wafer, bonding pressure and height of adhesive bonding layer. The availability of adhesive polymer bonding was confirmed by TC, HTC, Humidity soak test after dicing. The result is that defect has not found without reference to warpage.

• Korean Journal of Materials Research
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• v.16 no.10
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• pp.652-655
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• 2006

A direct wafer bonding process necessary for GaAs-on-insulator (GOI) fabrication with high thermal annealing temperatures was studied by using PECVD oxides between gallium arsenide and silicon wafers. In order to apply some uniform pressure on initially-bonded wafer pairs, a graphite sample holder was used for wafer bonding. Also, a tool for measuring the tensile forces was fabricated to measure the wafer bonding strengths of both initially-bonded and thermally-annealed samples. GaAs/$SiO_2$/Si wafers with 0.5-$\mu$m-thick PECVD oxides were annealed from $100^{\circ}C\;to\;600^{\circ}C$. Maximum bonding strengths of about 84 N were obtained in the annealing temperature range of $400{\sim}500^{\circ}C$. The bonded wafers were not separated up to $600^{\circ}C$. As a result, the GOI wafers with high annealing temperatures were demonstrated for the first time.

• Transactions of Materials Processing
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• v.31 no.4
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• pp.179-185
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• 2022

The influence of post-roll bonding heat treatment conditions such as temperature and time on the variation in the diffusion layer, generated at the bonding interface and the subsequent mechanical properties of the roll-bonded Ti grade 1/Al1050/Ti grade 1 sheets, was systematically investigated. The intermetallic compound (IMC) phase generated by post heat treatment conditions adopted in this study was obviously indexed as monolithic TiAl₃. Whereas the thickness of IMC layer generated by annealing at 500 ℃ was approximately 100 nm scale, it drastically increased above 1.5 ㎛ when annealed at 600 ℃. Uniaxial tensile and peel tests were then performed to compare mechanical properties. As a result, the bonding strength drastically increased above 7.9 N/mm by annealing at 600 ℃, which implies that proper annealing condition was a prerequisite, to improving interface bonding strength as well as global elongation properties for Ti/Al/Ti 3-ply sheet.

• Journal of Korea Foundry Society
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• v.38 no.1
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• pp.16-26
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• 2018

In this study, the effects of the pouring temperature, preheating temperature, surface condition and fraction of the wear resistant part on the production of duo-castings were investigated using a high Cr white cast iron with excellent abrasion resistance and a low Cr alloy steel with good toughness. The constituent materials of the duo-castings were designed to have high hardness, fracture toughness and abrasive wear resistance for the replacement of high Mn alloy steels with low abrasive wear resistance. In particular, the amount of abrasive wear of 17% Cr white cast iron was about 1/20 of that of high Mn alloy steel. There was an intermediate area of about 3mm due to local melting at the bonding interface of the duo-castings. These intermediate regions were different from those of the constituent materials in chemical composition and microstructure. This region led to fracture within the wear resistant part rather than at the bonding interface in the bending strength test. The bending fracture strengths were 516-824 MPa, which were equivalent to the bending proof strength of high Mn steel. The effects of various casting conditions on the duo-cast behavior were studied by simple pouring of low Cr alloy steel melt, but the results proved practically impossible to manufacture duo-castings with a sound bonding interface. However, the external heating method was suitable for the production of duo-castings with a sound bonding interface.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.830-833
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• 2003

This paper describes the fabrication and characteristics of 3C-SiCOI sotctures by SDB and etch-back technology for high-temperature MEMS applications. In this work, insulator layers were formed on a heteroepitaxial 3C-SiC film grown on a Si(001) wafer by thermal wet oxidation and PECVD process, successively. The pre-bonding of two polished PECVD oxide layers made the surface activation in HF and bonded under applied pressure. The wafer bonding characteristics were evaluated by the effect of HF concentration used in the surface treatment on the roughness of the oxide and pre-bonding strength. Hydrophilic character of the oxidized 3C-SiC film surface was investigated by ATR-FTIR. The strength of the bond was measured by tensile strengthmeter. The bonded interface was also analyzed by SEM. The properties of fabricated 3C-SiCOI structures using etch-back technology in TMAH solution were analyzed by XRD and SEM. These results indicate that the 3C-SiCOI structure will offers significant advantages in the high-temperature MEMS applications.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.18-21
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• 2003

The effect of interface bonding strength on the recovery force of SMA wire reinforced polymer matrix composites was investigated by pullout test. Firstly, the recovery forces and transformation temperatures of various prestrained SMA wires were measured and 5% prestrained SMA wires were prepared for the reinforcements of composites. EPDM incorporated with 20vol% silicon carbide particles(SiCp) of 6, 12, $60{mutextrm{m}}$ size were used as matrix. Pullout test results showed that the interface bonding strength increased when the SiCp size decreased due to the increase of elastic modulus of matrix. Cyclic test of composites was performed through control of DC current at the constant displacement mode. The abrupt decrease of recovery force during cycle test at high current was occurred by thermal degradation of matrix. This was in good agreement with temperature related in the thermal degradation of matrix. The hysteresis of recovery force with respect to the temperature was compared between wire and composite and the hysterisis of composites was smaller than the wire due to less thermal conduction.

• Journal of Korea Foundry Society
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• v.13 no.1
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• pp.42-49
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• 1993

Conventional manufacturing process for cast iron-babbitt metal composite is complicate and bimetallic bonding by centrifugal casting is also difficult because their melting point is largely different and nonmetallic inclusion exists on outer shell. This study is aiming to simplify multistage process by adding Cu-powder as insert metals during cast iron solidification. The variables on fabrication of composite pipe are mold rotating speed and inner surface temperature of outer metal. The optimum temperature range for fusion bonding between cast iron and Cu-layer was $1100^{\circ}C-1140^{\circ}C$ in case of mold rotating speed was 700rpm. When the inner surface of Cu-layer was at $900^{\circ}C$, the value of interfacial hardness between Cu-layer and babbitt metal were higher than Cu-matrix by forming diffusion layer, interfacial products between Cu-layer and babbitt metal are proved to be $Cu_6Sn_5({\eta})$by XRD.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.11 no.1
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• pp.12-19
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• 2015

As a measure of improving the mechanical properties of a diffusion bonded joint of a ferritic/martensitic steel (FMS), the post-bonding heat treatment (PBHT) is applied. In the temperature range of normalizing condition ($950-1,050^{\circ}C$), diffusion bonding is employed with compressive stress (6 MPa). Due to the martensite structure distributed in the matrix, Vicker's hardness values of the as-bonded are much higher than those of the as-received. Through the PBHT for 1 h at $720^{\circ}C$, hardness values are recovered to as low as those of the as-received condition. Also, tensile properties of PBHT are similar to those of the as-received at up to the test temperature of $550^{\circ}C$, when the diffusion bonding is carried out over $1,000^{\circ}C$. Based on the creep-rupture testing performed at $650^{\circ}C$ in air environment, the joint efficiency of the PBHTed specimens is about 80% in, which is higher than that of the as-bonded specimens.

• Journal of Sensor Science and Technology
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• v.7 no.3
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• pp.211-217
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• 1998

Si and ITO-coated #7059 glass wafers were electrostatically bonded by employing #7740 interlayer. It was inferred that the thermionic- electrostatic migration of $Na^{+}$ ions in the #7740 interlayer played an important role in the bonding process through SIMS analysis. The temperature and voltage required for reliable electrostatic bonding were in the range of $180{\sim}200^{\circ}C$ and $50{\sim}70V_{dc}$(10min), respectively. The low temperature Si-ITO coated glass bonding can be effectively applied to the packaging of field emission devices.