Title :
Improved reliability of SiC pressure sensors for long term high temperature applications
Author :
Okojie, R.S. ; Nguyen, V. ; Savrun, E. ; Lukco, D.
Author_Institution :
NASA Glenn Res. Center, Cleveland, OH, USA
Abstract :
We report advancement in the reliability of silicon carbide pressure sensors operating at 600°C for extended periods. The large temporal drifts in zero pressure offset voltage at 600°C observed previously were significantly suppressed to allow improved reliable operation. This improvement was the result of further enhancement of the electrical and mechanical integrity of the bondpad/contact metallization, and the introduction of studded bump bonding on the pad. The stud bump contact promoted strong adhesion between the Au bond pad and the Au die-attach. The changes in the zero offset voltage and bridge resistance over time at temperature were explained by the microstructure and phase changes within the contact metallization, that were analyzed with Auger electron spectroscopy (AES) and field emission scanning electron microscopy (FE-SEM).
Keywords :
Auger electron spectra; adhesion; field emission electron microscopy; pressure sensors; reliability; scanning electron microscopy; silicon compounds; AES; Auger electron spectroscopy; FE-SEM; SiC; adhesion; bondpad-contact metallization; electrical integrity; field emission scanning electron microscopy; long term high temperature application; mechanical integrity; piezoresistive pressure sensor; reliability; studded bump bonding; temperature 600 degC; Gold; Metallization; Resistance; Silicon carbide; Temperature measurement; Temperature sensors; High Temperature; Offset Voltage Drift; Pressure Sensor; Reliability; Silicon Carbide;
Conference_Titel :
Solid-State Sensors, Actuators and Microsystems Conference (TRANSDUCERS), 2011 16th International
Conference_Location :
Beijing
Print_ISBN :
978-1-4577-0157-3
DOI :
10.1109/TRANSDUCERS.2011.5969561
