burn-in

A stress-testing process for semiconductor chips to detect early failures before they are shipped to customers.

Burn-in is a critical stress-testing phase in semiconductor manufacturing where silicon chips are subjected to extreme thermal and electrical stress—typically high temperatures and elevated voltages—for a specified duration. The primary objective is to accelerate the aging process of the chips to force latent manufacturing defects, which would otherwise cause early-stage failures in the hands of customers, to manifest while still in the factory. This testing is essential for high-reliability applications such as automotive systems, aerospace, medical devices, and artificial intelligence data centers, where a single chip failure can lead to catastrophic system downtime or safety hazards. The process relies on specialized burn-in ovens, test chambers, and high-performance contactors or sockets that interface directly with the silicon wafers or packaged chips. For technology and semiconductor investors, monitoring the demand for burn-in equipment and services provides a valuable leading indicator of industry health. High demand for advanced burn-in testing often signals the commercial rollout of complex, next-generation chip architectures, such as high-performance AI accelerators or advanced packaging designs. Conversely, a sudden drop in burn-in equipment orders can signal an impending cyclical slowdown or overcapacity in chip manufacturing.

A semiconductor testing facility runs a batch of 1,000 newly manufactured microprocessors through a 24-hour burn-in cycle at 125 degrees Celsius. During the test, 15 chips fail due to latent gate-oxide defects. The early failure rate is calculated as 15 / 1,000 = 1.5%, allowing the manufacturer to discard the defective units before shipping the remaining 985 reliable chips to customers.