Using I/sub DDQ/ drift testing to detect hydrogen in MOS devices

This paper will show how I/sub DDQ/ drift testing was used to detect hydrogen in BiCMOS IC's. The paper will provide mobile ion testing results, using several methods, to show that there were very few mobile ions in the IC's to account for the drift. The paper will then show wafer level reliability (WLR) test data to support the conclusion that hydrogen is in the IC. I/sub DDQ/ drift testing will show that sodium is not the cause of the drift but the drift is due to hydrogen. The paper will than present a model of how hydrogen causes I/sub DDQ/ drift. The model is based upon the hydrogen compensation of boron. I/sub DDQ/ drift testing will then be used to evaluate an experiment involving different forming gas alloy times and temperatures. The I/sub DDQ/ drift test results of this experiment show that as the alloy time and temperature are increased the incorporation of hydrogen in the IC is increased.