Reliability and failure analysis of UHF RFID passive tags under thermal storage

International audience—This paper proposes to study the effects of thermal storage on the reliability of passive UHF RFID tags. Two types of tags M1 and M2 from two different manufacturers are aged under two high temperatures equal to 413 K and 433 K. Tested tags are put into a thermal storage oven hang fixed terms. The performances of these tags are measured after each aging phase to determine the power loss caused by the high temperature storage. Then a mathematical approach is used to estimate for both tags from the two manufacturers the law of reliability under nominal conditions. Statistical and physical analyses of the results allow us to study and analyze the mechanisms of aging. It is observed that the failure mechanisms depend on the type of passive tags and the values of selected storage temperatures for the tests. The scale parameters of M1 tags aged at 413 K are around 280 hours, whereas the scale parameters of the M2 tags aged at same temperature are around 360 hours. Cracks on the antenna are observed with the higher temperature equal to 433 K for M1 tags. However, the changes of the performance of others tags are probably caused by changes in the matching of the impedance between the antenna and the RFIC. From this study, various failure mechanisms demonstrate the necessity of determining the type of passive tags and the used temperature