Specimen Preparation and Atom Probe Field Ion Microscopy of BSCCO-2212 Superconductors

Abstract

Field ion specimens of BizSr2CaCu20x (BSCCO) high temperature superconductor (HTS) materials have been prepared using a combination of three different preparation techniques: the method of sharp shards, electropolishing and ion milling. Field ion microscopy (FIM) has demonstrated that samples which exhibit the "striped"-image contrast characteristic of HTS materials can be successfully fabricated using this combination. FIM images have been obtained which show the striped-image contrast much clearer than any previously published images of Pb-free BSCCO. Prelimina~y atom probe (AP) chemical analysis of the material was also performed. Analytical electron microscopy was used to confirm the existence of both the correct crystallographic structure and nominal composition in the near-apex region of the specimen after preparation and FIM.

Probing structural and chemical evolution in (AlxGa1−x)2O3 using atom probe tomography: A review

“…To obtain a rich data set in the APT experiment that would reveal significant information about the atomic-level structure and compositions of the materials, certain procedure is followed from preparing the needle-shaped specimen from any given bulk wafer till advanced data analysis. Similar to different materials, ranging from metals to semiconductors, atom probe experiments for wide bandgap (Al x Ga 1−x ) 2 O 3 were carried out in three steps: (i) needle-shaped specimen preparation, (ii) data acquisition, and (iii) tip reconstruction and subsequent data analysis [74,75,76,77]. In the following sub-sections, we will provide a brief description of each step.…”

“…Premature specimen fracture is likely to occur in heterostructure samples as the voltage-induced stress is more likely to exceed the mechanical stability of the tip, especially while passing through the interfaces [81,82]. Focused ion beam (FIB)-based lift-out and annular milling was performed as outlined by Larson et al [57,75,83,84] for sample preparation. This method is most widely used for APT specimen preparation, especially, when multilayer semiconductor materials are involved [85].…”

Probing structural and chemical evolution in (AlxGa1−x)2O3using atom probe tomography: A review

“…Premature specimen fracture is likely to occur in heterostructure samples as the voltage-induced stress is more likely to exceed the mechanical stability of the tip, especially while passing through the interfaces [81,82]. Focused ion beam (FIB)-based lift-out and annular milling was performed as outlined by Larson et al [57,75,83,84] for sample preparation. This method is most widely used for APT specimen preparation, especially, when multilayer semiconductor materials are involved [85].…”

Sharpening of field-ion specimens and positioning of features of interest by ion-beam milling

“…Ion etching of conical-shaped metal and semiconductor samples was investigated by Walls, Southworth, and Ruston with 6 keV argon ions and a rotating sample. Kvist, Andren, and Lundin 8 and Larson et al 9 have also investigated the use of a͒ Current address: Seagate Technology, M/S NRW 102, 7801 Computer Ave., Minneapolis, MN 55435-5489; electronic mail: DAVID_J_ LARSON@NOTES.SEAGATE.COM ion beams in field-ion specimen preparation. Henjered and Nordén 6 and Hellsing 7 have used ion milling to prepare field-ion samples from cemented carbide material, which is difficult to electropolish due to its multiphase nature.…”