Defect Activation Through Hydrogen Release in Semiconductors
Laura Nichols, Vanderbilt University
Semiconductor devices make up all of modern electronics, so, in addition to modeling performance, it is necessary to also understand and model the degradation processes that cause reliability issues. Defects, such as dangling bonds at the Si/SiO2 interface in a MOSFET, exist in these devices, but they are hydrogenated in the fabrication process, making them neutral and without a level in the gap to capture carriers. Highly-energetic (hot) carriers can transfer energy to the defect and cause hydrogen to be released. Dehydrogenated defects are considered active as they are often charged and can scatter or capture carriers. In prior work, the activation probability has been examined through a defect-activation cross section that was assumed to be a step function with a minimum activation energy. No work had been done from first-principles to find this cross section, but there had been extensive work on carrier-capture cross sections.
However, prior applications of the capture theory were limited by considering energy dissipation into a single phonon mode because there is an exploding number of possible phonon configurations as more modes are allowed to participate. First, we revamped the approach to the capture problem by developing a time-domain integration method that allows for quick calculations of all possible phonon configurations. We then developed an algorithm on top of the capture problem to calculate the average activation lifetime of a hydrogenated defect due to energy transfer from multiple carriers. We present the results obtained with the new capture formalism and the algorithm to use the new formalism to consider hydrogen release.
Authors: Laura R. Nichols1, Guanzhi Li2, Georgios D. Barmparis3, X.-G. Zhang2, Sokrates T. Pantelides1,4
1Department of Physics and Astronomy, Vanderbilt University, USA
2Department of Physics and the Quantum Theory Project, University of Florida, USA
3Institute of Theoretical and Computational Physics, Department of Physics, University of Crete, Greece
4Department of Electrical and Computer Engineering, Vanderbilt University, USA
Abstract Author(s): (see above entries)