Aehr Announces New Customer and Initial Order for FOX-XP Multi-Wafer Test and Burn-in System for Volume Production of Silicon Carbide MOSFETs - Seite 2

“Wafer level burn-in is critically important to remove infant mortality or early failures of devices before they are put into modules, where the failure of any device would cause the entire module to fail and be scrapped. A single module for use in large traction inverters such as commuter trains might include up to 10, 12, or even 32 devices. Our FOX-XP wafer level system can test and burn-in up to 18 wafers at a time and enables contact to 100% of the die in a single touchdown up to several thousand die per wafer, with 100% confidence of test burn-in of each device. This is key to companies wanting to put these devices in electric vehicle applications, where up to one percent or more of the die would fail in the field if not burned in.

“In addition, beyond screening out weak devices or early failures before they are put into a module, there is a need to stabilize the inherent early life drift of threshold voltages of devices that is critical to the module reliability. Silicon carbide devices have voltage thresholds, which is effectively the voltage at which each individual device turns on and will drift during the first use, or during burn-in stress conditions under thermal loads. This can cause individual die in a multi-die module to turn on prematurely relative to the other die in parallel, which can create a disproportional stress on the die leading to its early failure. This in turn will lead to the failure of the entire module. This failure must be screened out to prevent a “walk home event,” whereupon with the failure of the traction inverter module, the drive unit will fail, leading to the driver and all the passengers having to get out of the electric vehicle and walk home.”

The FOX-XP system, available with multiple WaferPak Contactors (full wafer test) or multiple DiePak^TM Carriers (singulated die/module test) configurations, is capable of functional test and burn-in/cycling of integrated devices such as silicon carbide (SiC) power devices, silicon photonics as well as other optical devices, 2D and 3D sensors, flash memories, Gallium Nitride (GaN), magnetic sensors, microcontrollers, and other leading-edge ICs in either wafer form factor, before they are assembled into single or multi-die stacked packages, or in singulated die or module form factor.