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Revealing the Bonding Environment of Zn in ALD Zn(O,S) Buffer Layers through X-ray Absorption Spectroscopy.

ABSTRACT: Zn(O,S) buffer layer electronic configuration is determined by its composition and thickness, tunable through atomic layer deposition. The Zn K and L-edges in the X-ray absorption near edge structure verify ionicity and covalency changes with S content. A high intensity shoulder in the Zn K-edge indicates strong Zn 4s hybridized states and a preferred c-axis orientation. 2-3 nm thick films with low S content show a subdued shoulder showing less contribution from Zn 4s hybridization. A lower energy shift with film thickness suggests a decreasing bandgap. Further, ZnSO4 forms at substrate interfaces, which may be detrimental for device performance.

SUBMITTER: Dadlani A

PROVIDER: S-EPMC5691320 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Revealing the Bonding Environment of Zn in ALD Zn(O,S) Buffer Layers through X-ray Absorption Spectroscopy.

Dadlani Anup A Acharya Shinjita S Trejo Orlando O Nordlund Dennis D Peron Mirco M Razavi Nima N Berto Filippo F Prinz Fritz B FB Torgersen Jan J

ACS applied materials & interfaces 20171102 45

Zn(O,S) buffer layer electronic configuration is determined by its composition and thickness, tunable through atomic layer deposition. The Zn K and L-edges in the X-ray absorption near edge structure verify ionicity and covalency changes with S content. A high intensity shoulder in the Zn K-edge indicates strong Zn 4s hybridized states and a preferred c-axis orientation. 2-3 nm thick films with low S content show a subdued shoulder showing less contribution from Zn 4s hybridization. A lower ener ...[more]

PMID: 29083141

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