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Article
Publication date: 29 April 2014

Seok-Hwan Huh, Kang-Dong Kim and Keun-Soo Kim

The purpose of this paper is to evaluate the relationship between the Cu trace and epoxy resin and to check the validity of surface and interfacial cutting analysis system…

Abstract

Purpose

The purpose of this paper is to evaluate the relationship between the Cu trace and epoxy resin and to check the validity of surface and interfacial cutting analysis system (SAICAS) by comparing its results to those of the 90° peel test.

Design/methodology/approach

In this study, the effects of surface morphology on the adhesion strength were studied for a Cu/epoxy resin system using a SAICAS. In order to evaluate the peel strength of the sample, the curing degree and surface morphology of the epoxy resin were varied in the Cu/epoxy resin system.

Findings

The results indicated that the peel strength is strongly affected by the curing degree and the surface morphology of the epoxy layer. As the pre-cure time increased, the interactions between the epoxy resin and permanganate during the adhesion promotion process decreased, which decreased the surface roughness (Ra) of the resin. Therefore, the surface roughness of the epoxy resin decreased with increasing pre-cure time. The curing degree was calculated with the FTIR absorption peak (910 cm−1) of the epoxy groups. The high curing degree for the epoxy resin results in a coral-like morphology that provides a better anchoring effect for the Cu trace and a higher interfacial strength.

Research limitations/implications

It is necessary to study the further adhesion strength, i.e. the friction energy, the plastic deformation energy, and the interfacial fracture energy, in micro- and nanoscale areas using SAICAS owing to insufficient data regarding the effects of size and electroplating materials.

Originality/value

From findings, it is found that measuring the peel strength using SAICAS is particularly useful because it makes the assessment of the peel strength in the Cu/epoxy resin system of electronic packages possible.

Details

Circuit World, vol. 40 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 12 December 2019

Wooju Kim, Ki-Ok Jeong, Ho-Lyeong Cheon and Dong-Hyun Kang

Biofilms are bacterial communities embedded in exopolysaccharide, enhancing the difficulty of detaching bacterial cells from surfaces. Due to structural properties, it is…

Abstract

Purpose

Biofilms are bacterial communities embedded in exopolysaccharide, enhancing the difficulty of detaching bacterial cells from surfaces. Due to structural properties, it is difficult to detach biofilms. Many removal methods have been developed, but there are still some limitations such as sample size and reproducibility. “Spindle” was developed, producing a higher quality suspension which can be used for further study. The paper aims to discuss these issues.

Design/methodology/approach

The authors compared the enumeration of biofilm-forming cells detached from the spindle and stomacher in various surfaces. First, the authors chose stainless steel and polyvinyl chloride to attach biofilms and to be subjected to stomacher and spindle for up to 2 min. Also, the authors evaluated the efficiency of detachment from vegetable surfaces.

Findings

In a comparative experiment of abiotic surfaces, the spindle showed identical effectiveness for detaching biofilm-forming cells compared to the stomacher, recovering the population by 8-log for Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes. The spindle also showed no significant difference from the stomacher in the number of recovered cells which is 4-log from vegetable surfaces. However, turbidity after spinach was subjected to spindle was 4.37 NTU, while it was 99 NTU for stomacher, which was in accord with visual result about clearance.

Originality/value

This study demonstrated that the spindle is a useful to separate biofilms from surfaces without destructing structure, and thus it can be used for analysis in food laboratories as well as utilized for vegetable washing step in the food industry.

Details

British Food Journal, vol. 122 no. 2
Type: Research Article
ISSN: 0007-070X

Keywords

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