Impact of field-plate geometry on the reliability of GaN-on-SiC HEMTs

• GaN HEMT with different gate field-plate geometries have been tested.
• Increasing field-plate length improves the device large signal performances.
• Increasing field-plate length improves device stability during RF stress test.

GaN on SiC HEMTs fabricated with different gate-connected field plate structures have been tested by means of RF reliability tests. The increase in field-plate length yielded an improvement of both the dynamic and the reliability performance during RF testing. Results are thus suggesting that reliability in field-plate devices can be improved by a proper design of the field-plate geometry.