Phase formation and texture of thin nickel germanides on Ge(001) and Ge(111)

Publication Type:

Journal Article

Source:

Journal of Applied Physics, Volume 119 (2016)

URL:

http://scitation.aip.org/content/aip/journal/jap/119/13/10.1063/1.4945317

Abstract:

We studied the solid-phase reaction between a thin Nifilm and a single crystal Ge(001) or Ge(111) substrate during a ramp anneal. The phase formation sequence was determined using in situX-ray diffraction and in situRutherford backscattering spectrometry (RBS), while the nature and the texture of the phases were studied using X-ray pole figures and transmission electron microscopy. The phase sequence is characterized by the formation of a single transient phase before NiGe forms as the final and stable phase. X-ray pole figures were used to unambiguously identify the transient phase as the ϵ-phase, a non-stoichiometric Ni-rich germanide with a hexagonal crystal structure that can exist for Ge concentrations between 34% and 48% and which forms with a different epitaxial texture on both substrate orientations. The complementary information gained from both RBS and X-ray pole figure measurements revealed a simultaneous growth of both the ϵ-phase and NiGe over a small temperature window on both substrate orientations.

© 2012-2015 CoCoon Research Department (works with IE7, firefox 3 or better). Drupal theme by Kiwi Themes.