Investigation of morphological changes in platinum-containing nanostructures created by electron-beam-induced deposition

Focused electron-beam-induced deposition (EBID) allows the rapid fabrication of three-dimensional nanodevices and metallic wiring of nanostructures, and is a promising technique for many applications in nanoresearch. The authors present two topics on platinum-containing nanostructures created by EBID. First, they report on a TEM study of the microstructure of nanodeposits created from Pt(PF(3))(4). They have performed imaging and electron energy loss spectroscopy with a transmission electron microscope (TEM). The deposited material, composed mainly of platinum, phosphor, oxygen, and trace amounts of fluorine, is amorphous. Platinum is evenly distributed in the nanostructure, while phosphorus is observed to cluster. The size and amount of phosphorus clusters depend on the thickness of the structure. Second, they document an aging process in structures created from MeCpPtMe(3), which have a resistivity which increases with the time they are exposed to air, from 2x10(5) to 1.8x10(8) mu Omega cm over 55 days. They demonstrate that covering the structures with an EBID-deposited insulating protective layer of TEOS can prevent this oxidation. In doing so, they achieved the lowest reported resistivity for EBID from this platinum precursor, of 1.5x10(3) mu Omega cm.