• Proceedings of the KWS Conference
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• 2005.06a
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• pp.34-36
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• 2005

Copper wire bonding is an alternative interconnection technology that serves as a viable and cost saving alternative to gold wire bonding. In this paper, ultrasonic wedge bonding with $25{\mu}m$ copper wire on Au/Ni/Cu metallization of a PCB substrate was performed at ambient temperature. The central composite design of experiment (DOE) approach was applied to optimize the copper wire wedge bonding process parameters. After that, pull test of the wedge bond was performed to study the bond strength and to find the optimum bonding parameters. SEM was used to observe the cross section of the wedge bond. The pull test results show good performance of the wedge bond. Additionally, DOE results gave the optimized parameter for both the first bond and the second bond. Cross section analysis shows a continuous interconnection between the copper wire and Au/Ni/Cu metallization. The diffusion of Cu into the Au layer was also observed.

• Corrosion Science and Technology
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• v.20 no.5
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• pp.289-294
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• 2021

In this study, after measuring polarization characteristics of 97.3 wt% Ag, Au-Coated 97.3 wt% Ag (ACA) and 100 wt% Au wires in 1 wt% H₂SO₄ and 1 wt% HCl electrolytes at 25 ℃, corrosion rate and corrosion characteristics were comparatively analyzed. Comparing corrosion potential (E_CORR) values in sulfuric acid solution, ACA wire had more than six times higher E_CORR value than Au wire. Thus, it seems possible to use a broad applied voltage range of bonding wire for semiconductor packaging which ACA wire could be substituted for the Au wire. However, since the E_CORR value of ACA wire was three times lower than that of the Au wire in a hydrochloric acid solution, it was judged that the use range of the applied voltage and current of the bonding wire should be considered. In hydrochloric acid solution, 97.3 wt% Ag wire showed the highest corrosion rate, while ACA and Au showed similar corrosion rates. Additionally, in the case of sulfuric acid solution, all three types showed lower corrosion rates than those under the hydrochloric acid solution environment. The corrosion rate was higher in the order of 97.3 wt% Ag > ACA > 100 wt% Au wires.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.171-171
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• 2008

본 연구는 초음파 알루미늄 웨지 및 금 볼 본딩을 동시에 적용 가능한 본딩 Pad의 금속학적 안정성을 고려한 표층전극 형성 방법에 관한 것이다. 특히, 이동통신 및 전장용 모듈의 복합 및 융합화로 LTCC기판 패키징에 있어서 다양한 본딩 기술이 요구되고 있다. 전통적인 interconnection 기술인 Au ball 본딩 및 초음파 에너지를 이용한 Al wedge 본딩 기술이 동시에 사용되어야 하는 패키지 구조의 경우 본딩 패드의 표층전극 설계는 서로 상충되는 조건이 요구된다. 따라서, 본 연구에서는 LTCC기판의 표층전극의 Metal finish 방법으로 이용되는 ENEPIG(무전해 Ni/Pd/Au도금)공법으로 Au ball 본딩 및 초음파 Al wedge 본딩을 동시에 가능하게 하는 solution을 제시하여 패키징 자유도뿐만 아니라 Interconnection 신뢰성을 확보할 수 있었다.

• Journal of Adhesion and Interface
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• v.25 no.2
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• pp.63-68
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• 2024

In this study, the contamination of gold(Au) wire according to the types of rinse applied for surface treatment in the wire bonding process is investigated and confirmed. For the surface treatment, rinses containing silicon(Si) or those based on organic materials are mainly employed. To identify their effects, surface treatment is conducted on Au wire using two types of rinse at a 1.0 wt% concentration, referred to as Si-including and Oil-based rinse-coated Au wire. Subsequently, a simulation experiment is performed to verify the reactivity of dust containing Si components that could occur in the semiconductor process. Through optical microscopy (OM) and scanning electron microscopy(SEM) analysis, it is observed that a larger amount of dust is adsorbed on the surface of Si-including rinse-coated Au wire compared with the Oil-based rinse-coated Au wire. This is attributed that the rinse containing Si components is relatively polar, causing polar interactions with dust, which also has polarity. Therefore, it is expected that using a rinse without Si components can reduce contamination caused by dust, thereby decreasing the defect rate in the practical wire bonding process.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9B
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• pp.1635-1640
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• 2000

In this paper, a 18 GHz oscillator is designed with the push-push method an fabricated by semi-MMIC process, in which the second harmonic is the main output signal with the suppressed fundamental mode. In semi-MMIC process, passive components with microstrip transmission line are implemented using MMIC process on semi-insulating GaAs substrate. Then, chip types of P-HEMT, resistors, and capacitors are connected through Au wire-bonding. Also, the ground plane is inserted around the circuit and connected each other with the back-side of substrate through Au wire-bonding instead of via-hole. The semi-MMIC push-push oscillator shows the output powder of -10.5 dBm, the fundamental frequency suppression of -17.3 dBc/Hz, and the phase noise of -97.9 dBc/Hz at the offset frequency of 100 kHz.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.4-4
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• 2009

Surface analysis on defective wire-bonding pads are performed in flash memory assembly. Week wire bonding may cause a significant effect on the final product reliability, and the surface condition of the aluminum bond pads is critical in terms of product reliability. To find out possible week bonding on semiconductor interconnects, ball sheer test (BST) has been performed. On some defective or week bonded pads, we have investigated the surface contents, assuming that the week bonding is induced from the surface conditions. AES and XPS are employed for the quantitative surface analysis on defective dies.

• Journal of the Korean Society of Radiology
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• v.8 no.7
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• pp.371-376
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• 2014

The process of flip-chip bump bonding, Au wire bonding and encapsulation were sucessfully developed and modularized. The CdTe sensor and ROIC were optimally jointed together at $150^{\circ}C$ and $270^{\circ}C$ respectively under24.5 N for 30s. To make SnAg bump on ROIC easy to be bonded, the higher bonding temperature was established than CdTe sensor's. In addition, the bonding pressure was lowered minimally because CdTe Sensor is easier to break than Si Sensor. CdTe multi-energy sensor module observed were no electrical failures in the joints using developed flip chip bump bonding and Au wire bonding process. As a result of measurement, shearing force was $2.45kgf/mm^2$ and, it is enough bonding force against threshold force, $2kgf/mm^2s$.

• Journal of the Microelectronics and Packaging Society
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• v.31 no.2
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• pp.1-8
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• 2024

Bonding wires are composed of conductive metals of Au, Ag & Cu with excellent electrical conductivities for transmitting power and signals to wafer chips. Wire metals do not provide electrical insulation, adhesion promoter and corrosion passivation. Adhesion between metal wires is extremely weak, which is responsible for wire cut failures during thermal cycling. Organic coating for electrical insulation does not satisfy bondability and manufacturability, and it is complex to apply very thin organic coating on metal wires. Automotive packages require enhanced reliability of packages under harsh conditions. LED and power packages are susceptible to wire cut failures. Contrary to conventional OCB behaviors, forming gas was not required for free air ball formation for both Ag and Pd-coated Cu wires with Al₂O₃ passivation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.175-182
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• 2017

In light emitting diode (LED) chip packaging, wire bonding is an important process that connects the LED chip on the lead frame pad with the Au wire and enables electrical operation for the next process. The wire bonding process is divided by two types: thermo compression bonding and ultrasonic bonding. Generally, the wire bonding process consists of three steps: 1st ball bonding that bonds the shape of the ball on the LED chip electrode, looping process that hangs the wire toward another connecting part with a loop shape, and 2nd stitch bonding that forms and bonds to another electrode. This study analyzed the factors affecting the LED die bonding processes to optimize the process capability that bonds a small Zener diode chip on the PLCC (plastic-leaded chip-carrier) LED package frame, and then applied response surface analysis. The design of experiment (DOE) was established considering the five factors, three levels, and four responses by analyzing the factors. As a result, the optimal conditions that meet all the response targets can be derived.

• Proceedings of the KWS Conference
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• v.43
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• pp.46-48
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• 2004