Transient risk of water layer formation on PCBAs in different climates: Climate data analysis and experimental study
2022 (English)In: Microelectronics and reliability, ISSN 0026-2714, E-ISSN 1872-941X, Vol. 136, article id 114655Article in journal (Refereed) Published
Abstract [en]
The reliability of electronic devices depends on the environmental loads at which they are exposed. Climatic conditions vary greatly from one geographical location to another (from hot and humid to cold and dry areas), and the temperature and humidity vary from season to season and from day to day. High levels of temperature and relative humidity mean high water content in the air, but saturated conditions (i.e. 100 % RH) can also be reached at low temperatures. This paper analyses the relationship between temperature, dew point temperature, their difference (here called ΔT), and occurrence and time period of dew point closeness to temperature on transient condensation effects on electronics.
This paper has two parts: (i) Data analysis of typical climate profiles within the different zones of the Köppen -Geiger classification to pick up conditions where ΔT is very low (for example ≤0.4 °C). Various summary statistics of these events are calculated in order to assess the temperature at which these events happen, their durations and their frequency and (ii) Empirical investigation of the effect of ΔT ≤ 0.4 °C on the reliability of electronics by mimicking an electronic device, for which the time period of the ΔT is varied in one set of experiments, and the ambient temperature is varied in the other. The effect of the packaging of the electronics is also studied in this section.
The statistical study of the climate profiles shows that the transient events (ΔT ≤ 0.4 °C) occur in almost every location, at different temperature levels, with a duration of at least one observation (where observations were hourly in the database). The experimental results show that presence of the enclosure, cleanliness and bigger pitch size reduce the levels of leakage current, while similar high levels of leakage current are observed for the different durations of the transient events, indicating that these climatic transient conditions can have a big impact on the electronics reliability.
Place, publisher, year, edition, pages
Elsevier, 2022. Vol. 136, article id 114655
Keywords [en]
Climatic data, Condensation, Dew point, Packaging, Reliability, Time of wetness
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Quality technology and logistics
Identifiers
URN: urn:nbn:se:ltu:diva-92374DOI: 10.1016/j.microrel.2022.114655ISI: 000864790800009Scopus ID: 2-s2.0-85135567803OAI: oai:DiVA.org:ltu-92374DiVA, id: diva2:1685904
Projects
ELMAC (Electronics Manufactured for Climate)
Note
Validerad;2022;Nivå 2;2022-08-05 (hanlid);
Funder: Innovation Fund Denmark
2022-08-052022-08-052022-12-05Bibliographically approved