Thermal Damage to MLCC

Gideon Analytical Laboratories received one MLCC on a DC input noise filter PCB on which to perform failure analysis. MLCCs (Multi-Layered Ceramic Capacitors) are extremely ubiquitous in the electronics field; it was estimated that around 1000 billion are produced per year. The MLCC has severe thermal damage but was still intact to the pads via the termination solder connections.

Analytical services were provided. The MLCC could not be cut from the PCB and the PCB could not be cut because of the fragile nature of the condition. The MLCC had clearly been very hot; it burnt and carbonized the PCB, and molten metal was evident. The MLCC was cross-sectioned to reveal the cause of the failure.

Cross-sectioning revealed some interesting results. There was damage to the ceramic when it shorted, and there was evidence of electrical overstress (EOS). The pads were lifted from the PCB because the heat had burned the adhesive attaching the copper to the PCB but the solder fillets held. There were thermal cracks in the middle of the ceramic as well as the terminal area. EOS was apparent in two separate spots. The electrodes had an overwhelming number of thermal cracks that were indicative of board flexing.

Failure analysis performed by Gideon Analytical Laboratories netted revealed the true cause of the failure. The exact failure spot could not be located because it was burred by EOS damage. There were no manufacturing anomalies found in the good sections of the MLCC nor were there any solder issues with fillet or termination metal on the MLCC. There were, however, several red flags signaling board flexing.

Gideon Analytical Laboratories provides analytical services to a variety of companies within the electronics industry. Vast amounts of knowledge and experience in electrical engineering and chemistry allow Gideon Analytical Laboratories to achieve great analytical results that can pinpoint the nature of electronics failures. Imagine knowing exactly why and how devices fail and taking the necessary steps to prevent future failures. Whether it is in the design phase, manufacturing phase, or in the application phase, call Gideon Analytical Laboratories for all you failure analysis needs.

Board flexing cracks

Board flexing cracks

EOS engulfed electrodes

EOS engulfed electrodes

MLCC on PCB

MLCC on PCB

Large thermal cracks

Large thermal cracks

Thermal cracks by terminal

Thermal cracks by terminal