Reliability and failure analysis of MMIC amplifier fabricated onvarious GaAs substrates

摘要

The results are presented of stress aging characteristics of anion-implanted GaAs MMIC (monolithic microwave IC) IF amplifierfabricated on four different substrate materials: 3-in. undoped,chromium-doped, indium-doped, and highly polished, undoped GaAs LEC(liquid encapsulated Czochralski) substrates. Three long-term and sixaccelerated aging tests were performed on more than 900 amplifierstotaling 32000 hours. These tests indicate that primary factorsaffecting device lifetime are process variations, GaAs substratematerial, and substrate surface polish. Good reliability is predictedfor amplifiers fabricated on Cr-doped, undoped, and advanced polishedsubstrate. In-doped samples show instability and inadequate reliability.The failure analysis indicates that the primary causes of devicedegradation are GaAs-metal interface electromigration, interdiffusion,and active carrier density compensation