In-situ Charge Observation in Insulation Layers of Metal-base Printed Circuit Boards

2006 ◽  
Author(s):  
K. Okamoto ◽  
K. Fukunaga ◽  
T. Maeno
Keyword(s):  
Printed Circuit Boards ◽  
Circuit Boards ◽  
Metal Base ◽  
Printed Circuit

scholarly journals Recycling of Spent Hydrodehalogenation Catalysts – Problems Dealing with Separation of Aluminium

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Tomáš WEIDLICH ◽  
Barbora KAMENICKÁ
Keyword(s):  
Aqueous Solution ◽  
Printed Circuit Boards ◽  
Metal Salt ◽  
Volatile Components ◽  
Circuit Boards ◽  
Brominated Flame Retardant ◽  
Printed Circuit ◽  
Reductive Degradation ◽  
Zn Alloys

Our study is focused on utilization and recycling of copper and nickel applicable for reductive degradation of tetrabromobisphenolA (TBBPA), the high use brominated flame retardant for printed circuit boards. Deactivated and/or poisoned hydrodebrominationcatalysts are produced by reductive destruction of brominated phenol (TBBPA) dissolved in alkaline aqueous solution using RaneyAl-Ni and/or Devarda´s Al-Cu-Zn alloys. Spent metallic slurry is treated with aqueous sulfuric acid to dissolve residual aluminiumand/or zinc and decanted residual metal is subsequently treated under oxidation conditions and dissolved in excess of mineralacid by co-action of oxidant. The corresponding metal salt is separated from corresponding leachates containing excess of acid byevaporation and recycling of volatile components. Obtained copper or nickel salts were used as sources of Raney type hydrodebrominationcatalysts produced for in-situ by action of NaBH4.

In-Situ Thermal Chamber 3D X-Ray Computed Tomography for Non-Destructive Detection of Submicron Via-Crack in Printed Circuit Boards

2020 ◽  
Author(s):  
Daechul Choi ◽  
Sooyoung Ji ◽  
Jaelim Choi ◽  
Miyang Kim ◽  
Eunju Yang ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Printed Circuit Boards ◽  
Fault Isolation ◽  
Circuit Boards ◽  
X Ray ◽  
Printed Circuit ◽  
Thermal Chamber ◽  
X Ray Computed ◽  
Non Destructive

Abstract In this paper, we demonstrate a case for non-destructive detection of submicron wide via-crack in printed circuit boards (PCBs) by using in-situ thermal chamber 3D x-ray computed tomography. The defect location is verified by a PFA (Physical Failure Analysis), and good agreement was made. This fault isolation method is proposed as a possible solution for identifying submicron cracks in PCB substrates during challenging investigations.

scholarly journals Refinement of the method for selecting the width of the conductor of printed circuit boards on a metal base, working in the absence of convection

2021 ◽  
Vol 24 (3) ◽  
pp. 80-91
Author(s):  
Aleksey V. Kostin
Keyword(s):  
Printed Circuit Boards ◽  
Sufficient Accuracy ◽  
Logarithmic Scale ◽  
Graphical Methods ◽  
Conductive Heat ◽  
Circuit Boards ◽  
Metal Base ◽  
Printed Circuit ◽  
Refined Method

The article proposes a refined method for calculating the width of the conductors of printed circuit boards on a metal base for the onboard devices of spacecraft, depending on the current flowing. The constructed refined mathematical model of the process of conductive heat exchange between the conductors and the metal base is described. The results of calculations of various, most common, locations of layers of printed circuit boards are presented. An analysis was carried out and a refined methodology was developed based on the results obtained. It allows you to easily (without complicate calculations) calculate the necessary values of the width of conductors. This technique is based on graphical methods, but allows you to perform technical calculations with sufficient accuracy. Accuracy is achieved by using special formulas that simplify the determination of the value of a physical quantity on a logarithmic scale. The disadvantages of the proposed method are indicated.

A Novel Wet Etch In-situ Decapsulation of Devices on Boards

2010 ◽  
Author(s):  
Michael A. Gonzales ◽  
Joanna Kiljan
Keyword(s):  
Integrated Circuits ◽  
Printed Circuit Boards ◽  
Region Of Interest ◽  
Temperature Sensitive ◽  
Circuit Boards ◽  
Endpoint Detection ◽  
Printed Circuit ◽  
Novel Technique ◽  
Wet Etch

Abstract This paper presents a novel technique for decapsulation of integrated circuits (ICs) mounted on printed circuit boards. This technique overcomes wet etch related sidewall blowouts that damage or alter the performance of the IC and board under test. It also allows well defined etch geometries and better endpoint detection. This is accomplished by protecting the region of interest (ROI) with a fast-curing, acid-resistant maskant that peels off easily. The technique was successfully utilized on a densely populated board, which exhibited temperature sensitive failure mechanism, as discussed in this paper.

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