The interface of SiO2/ZnS films studied by high resolution X-ray photoluminescence

Shinjita Acharya; Orlando Trejo; Anup Dadlani; Jan Torgersen; Filippo Berto; Fritz Prinz

Theoretical and Applied Mechanics Letters (Jan 2018)

The interface of SiO2/ZnS films studied by high resolution X-ray photoluminescence

Shinjita Acharya,
Orlando Trejo,
Anup Dadlani,
Jan Torgersen,
Filippo Berto,
Fritz Prinz

Affiliations

Shinjita Acharya: Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA
Orlando Trejo: Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA
Anup Dadlani: Department of Chemistry, Stanford University, Stanford, CA 94305, USA
Jan Torgersen: Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, 7034 Trondheim, Norway; Corresponding author
Filippo Berto: Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, 7034 Trondheim, Norway
Fritz Prinz: Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305, USA

Journal volume & issue: Vol. 8, no. 1
pp. 24 – 27

Abstract

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ABSTRACT: Sharp interfaces in optoelectronic devices are key for proper band alignment. Despite its benefits as buffer layer, ZnS deposited via atomic layer deposition (ALD) renders intermixed interfaces to its substrate, which can be detrimental for device performance. Here, we are attempting to elucidate the chemical species deriving from this metal-oxide to metal-sulfide transition studying ultrathin film ZnS on SiO2 using high resolution X-ray photoluminescence spectroscopy (XPS). Regarding the S 2p spectra after a deposition of only three cycles of ZnS, we discover the many different chemical species in which S is present. These include intermediate oxides such as SO42-. These species become more obvious as we tilt the sample in the XPS chamber to shallower angles. Comparing the Si 2p and S 2p high resolution peaks in the depth profile, one can clearly uncover the confinement of SO42- to the interface of the underlying substrate. This may indicate that SiO2/ZnS interfaces contain interfacial sulphates that likely alter the electronic configuration of this interface. Keywords: Atomic Layer Deposition, Metal-Sulfide, Zinc Sulfide, Interface, High resolution X-ray photoluminescence spectroscopy

Published in Theoretical and Applied Mechanics Letters

ISSN: 2095-0349 (Print)
Publisher: Elsevier
Country of publisher: China
LCC subjects: Technology: Engineering (General). Civil engineering (General)
Website: http://www.journals.elsevier.com/theoretical-and-applied-mechanics-letters/

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