Zhihua Tao, Guanting Liu, Yuanxun Li and Hua Su
The adsorption and acceleration behavior of 3-mercaptopropyl sulfonate (MPS) were investigated by electrochemical tests for microvia filling by copper electroplating.
Abstract
Purpose
The adsorption and acceleration behavior of 3-mercaptopropyl sulfonate (MPS) were investigated by electrochemical tests for microvia filling by copper electroplating.
Design/methodology/approach
The synergistic effects of one suppressor of propylene oxide ethylene oxide propylene oxide named PEP and MPS as the accelerator during copper electroplating were also investigated by electrochemical methods such as electrochemical impedance spectroscopy cyclic voltammetric stripping (CVS) and Galvanostatic measurements (GMs).
Findings
The research results suggest that the adsorption of MPS onto the Cu-RDE metal surface was a spontaneous process and the adsorbing of MPS on cathode was proposed to physical-chemistry adsorption in the plating formula. There was no potential difference (i.e. ?? = 0) of GMs until MPS was injected into the plating solution suggest that copper deposition is not diffusion-controlled in the presence of PEP–Cl–JGB.
Originality/value
A new composition of plating bath was found to be effective to perform bottom-up copper filling of microvias in the fabrication of PCB in electronic industries. The adsorption of MPS into the Cu-RDE metal surface was a spontaneous process and the adsorbing of MPS on cathode was studied by EIS and the results proposed to physical-chemistry adsorption in the plating formula. An optimal plating solution composed of CuSO4, H2SO4, chloride ions, PEP, MPS and JGB was obtained, and the microvia could be fully filled using the plating formula.
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Yoksa Salmamza Mshelia, Simon Mang’erere Onywere and Sammy Letema
This paper aims to assess the current and future dynamics of land cover transitions and analyze the vegetation conditions in Abuja city since its establishment as the capital of…
Abstract
Purpose
This paper aims to assess the current and future dynamics of land cover transitions and analyze the vegetation conditions in Abuja city since its establishment as the capital of Nigeria in 1991.
Design/methodology/approach
A random forest classifier embedded in the Google Earth Engine platform was used to classify Landsat imagery for the years 1990, 2001, 2014 and 2020. A post-classification comparison was used to detect the dynamics of land cover transitions. A hybrid simulation model that comprised cellular automata and Markovian was used to model the probable scenario of land cover changes for 2050. The trend of Normalized Difference Vegetation Index was examined using Mann–Kendall and Theil Sen’s from 2014 to 2022. Nighttime band data from the National Oceanic and Atmospheric Administration were obtained to analyze the trend of urbanization from 2014 to 2022.
Findings
The findings show that built-up areas increased by 40%, while vegetation, bare land and agricultural land decreased by 27%, 7% and 8%, respectively. Vegetation had the highest declining rate at 3.15% per annum. Built-up areas are expected to increase by 17.1% between 2020 and 2050 in contrast with other land cover. The proportion of areas with moderate vegetation improvement is estimated to be 15.10%, while the proportion of areas with no significant change was 38.10%. The overall proportion of degraded areas stands at 46.8% due to urbanization.
Originality/value
The findings provide a comprehensive insight into the dynamics of land cover transitions and vegetation variability induced by rapid urbanization in Abuja city, Nigeria. In addition, the findings provide valuable insights for policymakers and urban planners to develop a sustainable land use policy that promotes inclusivity, safety and resilience.
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Dingqiang Sun, Michael Rickaille and Zhigang Xu
The purpose of this paper is to investigate the determinants and impacts of outsourcing pest and disease management on rice production in China.
Abstract
Purpose
The purpose of this paper is to investigate the determinants and impacts of outsourcing pest and disease management on rice production in China.
Design/methodology/approach
A multinomial endogenous treatment effects model which accounts for selection bias was used.
Findings
The results show that outsourcing decisions are driven mainly by the size of the farm, the age of the household head and other household characteristics. Further, the authors find that outsourcing labor for pest and disease control has no significant effect on pest control cost and rice yields, though it reduces the number of pesticide applications. Conversely, outsourcing of professional services can increase rice yields by 4.1 percent, and at the same time it increases pest and disease control costs by 50.6 percent. However, it is found that outsourcing of professional services exerts no significant impact on the farm profitability.
Practical implications
This study suggests that households with large farm size are more likely to outsource professional services and, therefore, service providers and governments should target those farmers to provide incentives and create greater awareness of the benefits from the outsourcing of professional services. Moreover, the increase in yields along with the government subsidy justifies the outsourcing of professional services by farmers. However, service providers and policy makers have a lot of leeway to come up with cheaper methods for pest and disease management in rice production.
Originality/value
This study is the first attempt to simultaneously evaluate the determinants and impacts of outsourcing pest and disease management on rice production in China.