Imaging Of Potential Gradient On Platinum Induced By Hydrogen Adsorption

The local gradient of electrostatic potential in the Pt gate of a Si-metal oxide semiconductor field effect transistor has been visualized using a phase reconstruction method with through-focus images of transmission electron microscopy based on the transport-of-intensity equation, which was quantitatively corrected by electron holography. The potential change by hydrogen adsorption in a specimen was detected by taking the difference between H-2-adsorbed and H-2-not-adsorbed phase images. We found that the potential gradient was localized at Pt interfaces and that the direction of the polarization was Pt inward. The direct visualization suggests that the potential gradient originated from hydrogen dipoles generated and located at the Pt interfaces. Published by AIP Publishing.