Reedholm Boosts Power Device DC Test System to 50A and 10kV
Enhanced test system satisfies growing need for wafer level screening of power devices
Reedholm Instruments has introduced an expansion of the industry's first DC test system for testing and characterising power devices at the wafer level. Maximum voltage is increased to 10kV from 2kV at a compliance current of 10mA, and high current testing is increased to 50A from 5A. Furthermore, high current can be reversed to make body diode measurements to 50A without having to do a second measurement pass.
High power devices built on SiC, GaN, and other types of substrates achieve maximum performance with vertical structures connecting the drain or collector to the wafer backside. Testing such devices on manual probers with a collection of instruments is satisfactory during early development, but low yields require reliable, high throughput testing when getting ready for market introduction.
"The main thing customers have asked for is a simple tool that quickly tests large sample sizes of product die in one probe pass," said Bill Trimble, Reedholm applications engineer. "They need this to show their customers that they can deliver in high volumes."
The RI-10kV/50A is a fully integrated DC test system configured for high-volume testing. Contact to the wafer is through Kelvin sensing leads capable of ±50A and +10kV. Instrumentation is built into the base of a low cost, high-speed prober that has been altered to be insensitive to catastrophic device breakdown. EMTS, a prober supplier in New Hampshire, modifies EG 2001 models to assure continued operation, despite rapid device breakdowns that would otherwise cause the prober to freeze or to lose control of chuck movement, leading to probe card and wafer damage.
Reedholm data-driven applications environment eliminates programming so that engineers responsible for the system and for interpreting its output are not diverted from device and process engineering.
A test controller mounted inside the prober table provides real-time control of instrumentation and prober. Operators and engineers access the system via a Windows computer running a test intranet application, simplifying system administration and operation.
