Accelerated Incoming Thermal Soak Verification Procedure for Sensor Lots
Accelerated incoming thermal soak verification exposes latent transducer parameter drift within 48 hours, enabling quantitative C=0 lot rejection before production integration.
Encapsulant Outgassing
Volatile Emission
Release of gas from a solid material under heat or vacuum. Encapsulant outgassing occurs when the polymers used to protect electronic chips discharge trapped solvents or moisture. These vapors can travel through the package and deposit on sensitive surfaces.
Contamination Risk
Condensed residues interfere with the optical clarity of lenses or the conductivity of electrical contacts. The encapsulant outgassing can lead to the formation of a film that blocks light in image sensors. In high voltage applications, these gases can reduce the dielectric strength and cause arcing.
This requires the use of low outgassing materials in space and medical electronics.
Thermal Acceleration
Heat increases the kinetic energy of the molecules and speeds up the release of volatiles. Encapsulant outgassing is often tested using thermogravimetric analysis to measure mass loss over time. The rate of emission is a function of the cure state of the polymer.
Fully cured materials exhibit lower levels of gas release than undercured ones.
Measurement Protocol
Standard tests quantify the total mass loss and the collected volatile condensable material. Encapsulant outgassing is measured against limits set by organizations like NASA to ensure compatibility with vacuum environments. Verification involves placing the sample in a heated chamber and measuring the buildup of residue on a chilled plate.
This ensures the long term stability of the protected assembly.