Absorption and diffusion of water in printed circuit boards

Influence of Water Ingress on Surface Discharges Occurring on the Silicone Gel Encapsulated Printed Circuit Boards Developed for Deep-Sea Applications

“…Recent literature works report that the weaker spots in high-power semiconductor modules are the trenches in between the metallization edges and ceramic substrates [5,[25][26][27]. These physical defects can be easily identified using a modern PD detection method and PRPD-based pattern analysis [5].…”

“…These conditions are inadequate as the modules and converters are applied in lower-or higher-pressure environments. In this context, the application of liquid-and gel-based dielectric materials become a necessity to provide electrical insulation and to offer a pressure-neutral solution [4,24,26,27]. Experiments on specific dielectric materials have indicated that their application increases the breakdown and partial discharge characteristics of the modules and power converters [2,4].…”

Humidity Buildup in Electronic Enclosures Exposed to Constant Conditions

“…Therefore, the use of polymer material for electronic enclosure increases the chance of moisture penetration due to the possibility of water molecules passing through the material and acting as a buffer for moisture content. Literature focuses mainly on the moisture absorption by laminates, plastic, and mould compounds [11][12][13][14][15][16][17][18][19]. Although the effect of humidity on the properties of components [20][21][22] has been investigated, studies related to the humidity ingress into electronic enclosures are limited [23][24], while other works focus on temperature performance [25][26].…”