eprintid: 10052509
rev_number: 16
eprint_status: archive
userid: 608
dir: disk0/10/05/25/09
datestamp: 2018-07-18 09:51:17
lastmod: 2020-02-12 13:57:20
status_changed: 2018-07-18 09:51:17
type: article
metadata_visibility: show
creators_name: Jiang, J
creators_name: Hirano, K
creators_name: Sakurai, K
title: Micro-imaging of buried layers and interfaces in ultrathin films by X-ray reflectivity
ispublished: pub
divisions: UCL
divisions: A01
divisions: B04
divisions: C05
divisions: F42
note: This is the published version of record. For information on re-use, please refer to the publisher’s terms and conditions.
abstract: X-ray reflectivity is a promising technique for characterizing buried layers and interfaces in ultrathin films because of its ability to probe the electron density profile along the depth in a non-destructive manner. While routine X-ray reflectivity assumes the in-plane uniformity of the sample to be measured, it is also quite important to see buried inhomogeneous/patterned layers and interfaces. The present paper describes the addition of spatial resolution and imaging capability to an X-ray reflectivity technique to visualize surfaces and buried interfaces. To visualize quite wide viewing area size quickly, the image reconstruction scheme has been employed instead of the scanning of microbeam. Though the mathematics is quite close to X-ray computer tomography, the technique gives the image contrast caused by the difference in reflectivity at each in-plane point in the thin film sample. By choosing a grazing angle, the image gives inhomogeneity of X-ray reflectivity at the specific wavevector transfer. With a collimated monochromatic synchrotron X-ray beam of 0.05 mm (H) × 8 mm (V), the intensity profiles of X-ray reflection projections have been taken at many different in-plane rotation angles, from 0° to 180°. We have succeeded in visualizing buried layers and interfaces of the 8 mm dia area with the spatial resolution of better than 20 μm. Because of the brilliance of synchrotron radiation, the typical measuring time is shorter than 1 min. Three analytical cases have been discussed: (i) imaging of a buried layer and an interface covered by a protection layer, (ii) distinguishing different local parts of different thicknesses in an ultrathin film, and (iii) selective imaging of a specific metal in the thin film form.
date: 2016-09-21
date_type: published
official_url: https://doi.org/10.1063/1.4962311
oa_status: green
full_text_type: pub
language: eng
primo: open
primo_central: open_green
article_type_text: Article
verified: verified_manual
elements_id: 1565246
doi: 10.1063/1.4962311
lyricists_name: Jiang, Jinxing
lyricists_id: JJIAA18
actors_name: Bracey, Alan
actors_id: ABBRA90
actors_role: owner
full_text_status: public
publication: Journal of Applied Physics
volume: 120
number: 11
article_number: 115301
issn: 1089-7550
citation:        Jiang, J;    Hirano, K;    Sakurai, K;      (2016)    Micro-imaging of buried layers and interfaces in ultrathin films by X-ray reflectivity.                   Journal of Applied Physics , 120  (11)    , Article 115301.  10.1063/1.4962311 <https://doi.org/10.1063/1.4962311>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10052509/1/1.4962311.pdf