Copper (Cu) wire has been extensively used in the semiconductors industry to replace gold wire because of its cost-effectiveness and high performance. However, it has a massive challenge because of its high oxidation rate, high hardness, and high susceptibility to corrosion which is time-sensitive under environmental conditions. One of the attractive factors to investigate is the electrolytes used in the assembly process of copper wire. However, these electrolyte chemicals may potentially affect the quality of the copper wire bond’s metallurgical interconnection, manifesting as copper corrosion. Therefore, this paper will investigate the mechanism of the electrolyte reaction and the chemicals. In addition, the metallurgical morphology of the copper wire observes through electron microscopy. The results suggest that corrosion occurs with a specific time rate, electrolyte type-dependent and metallurgical interconnection system. The Copper wire bonded on silver (Ag) plated lead frame (Cu-Ag-Cu) interconnection experiences a significant morphological change in most compared with other electrolyte systems. Furthermore, since it is a bimetallic element (Cu and Ag) thus, the corrosion type is galvanic.

Copper wire bonding has got attracted attention over gold wire bonding due to its lower cost. However, despite many unique aspects and properties of copper wire bonding, corrosion of copper wire bonding has become a point of interest as it leads to the failure of semiconductor packages. Current and future trends and development in miniaturization and multifunction of the semiconductor packages show semiconductor manufacturers to establish good wire bonding with high reliability. However, this trend becomes a significant challenge in respect of corrosion occurrence. Several studies on the corrosion of copper wire bonding; however, there is no considerable study in the integrated factors leading to corrosion. Therefore, this paper focuses on investigating the corrosion phenomena of wire copper wire bonding, especially wedge bonds. This paper use a combination of the problem-solving approach for a complex problem. The analysis suggested that the weightage of factors, depending on process parameters and process steps, play a particular role in facilitating or preventing corrosion on the copper wire bonding. Therefore, it is essential to consider these factors when designing assembly process steps and parameters to control corrosion in semiconductor packages.

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Delamination of small outline transistor (SOT) package has been a challenge to ensure good package reliability. Molding process parameter optimization is a practical & cost-effective alternative to reduce delamination of the plastic package. First, selective molding parameters, namely, molding temperature, transfer speed, transfer pressure & pre-heat temperature was varied in a full factorial experiment to determine the significance of each factor. It is observed from the complete factorial analysis that molding temperature was the most significant factor concerning delamination. Next, one factor at a time (OFAT) experimental design was conducted to confirm moulding temperature’s repeatability. Molding temperature was identified as a significant factor on determining the delamination response of SOT packages. Lowering mold temperature resulting to lower percentage of delamination however proven to have an adverse on package curing density.