Low temperature chip on film bonding technology for 20 µm pitch applications

Kim, Sun-Chul; Kim, Young‐Ho

doi:10.1007/s10854-015-4205-7

Cited by 8 publications

(2 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As an example, Ji-Soo Lee et al achieved more stable fine-pitch FOF assemblies by incorporating an optimized post-flux activator into nanofiber solder ACF [38]. Shuyue Zhang and Sun-Chul Kim et al [39][40][41] investigated various applications of ACFs in 100 µm fine-pitch flexible printed circuits (FPCs) and achieved improved electrical properties and enhanced reliability of FOF by optimizing the material properties of ACF components. However, there is a lack of analysis concerning the size effects of conductive particles on the performance of ACFs under flexible mechanical conditions.…”

Section: Introductionmentioning

confidence: 99%

Size Effects of Au/Ni-Coated Polymer Particles on the Electrical Performance of Anisotropic Conductive Adhesive Films under Flexible Mechanical Conditions

Fang,

Wang,

et al. 2024

Materials

View full text Add to dashboard Cite

In soft electronics, anisotropic conductive adhesive films (ACFs) are the trending interconnecting approach due to their substantial softness and superior bondability to flexible substrates. However, low bonding pressure (≤1 MPa) and fine-pitch interconnections of ACFs become challenging while being extended in advanced device developments such as wafer-level packaging and three-dimensional multi-layer integrated circuit board assembly. To overcome these difficulties, we studied two types of ACFs with distinct conductive filler sizes (ACF-1: ~20 μm and ACF-2: ~5 μm). We demonstrated a low-pressure thermo-compression bonding technique and investigated the size effect of conductive particles on ACF’s mechanical properties in a customized testing device, which consists of flexible printing circuits and Flex on Flex assemblies. A consistency of low interconnection resistance (<1 Ω) after mechanical stress (cycling bending test up to 600 cycles) verifies the assembly’s outstanding electrical reliability and mechanical stability and thus validates the great effectiveness of the ACF bonding technique. Additionally, in numerical studies using the finite element method, we developed a generic model to disclose the size effect of Au/Ni-coated polymer fillers in ACF on device reliability under mechanical stress. For the first time, we confirmed that ACFs with smaller filler particles are more prone to coating fracture, leading to deteriorated electrical interconnections, and are more likely to peel off from substrate electrode pads resulting in electrical faults. This study provides guides for ACF design and manufacturing and would facilitate the advancement of soft wearable electronic devices.

show abstract

Section: Introductionmentioning

confidence: 99%

Size Effects of Au/Ni-Coated Polymer Particles on the Electrical Performance of Anisotropic Conductive Adhesive Films under Flexible Mechanical Conditions

Fang,

Wang,

et al. 2024

Materials

View full text Add to dashboard Cite

show abstract

“…Display device will become more compact sizes and more multifunctions, correspondingly, the technology requirement of display module packaging is growing 1,2 . Anisotropic conductive film (ACF) is a promising interconnection material 3,4 , used to bond chip on film (COF) or chip on plastic (COP) substrate with a display panel. ACF is composed of binder polymer resin and conductive particles.…”

Section: Introductionmentioning

confidence: 99%