Growth, intermixing, and surface phase formation for zinc tin oxide nanolaminates produced by atomic layer deposition

Journal Article · Tue Mar 15 04:00:00 EDT 2016 · Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films

DOI:https://doi.org/10.1116/1.4941411· OSTI ID:22489810

Hägglund, Carl ^[1]; Grehl, Thomas; Brongersma, Hidde H. ^[2]; Tanskanen, Jukka T.; Mullings, Marja N.; Mackus, Adriaan J. M.; MacIsaac, Callisto; Yee, Ye Sheng ^[3]; Clemens, Bruce M. ^[4]

---

1. Department of Chemical Engineering, Stanford University, Stanford, California 94305 and Department of Engineering Sciences, Division of Solid State Electronics, Uppsala University, 75121 Uppsala (Sweden)
2. ION-TOF GmbH, Heisenbergstraße 15, 48149 Münster (Germany)
3. Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)
4. Department of Material Science and Engineering, Stanford University, Stanford, California 94305 (United States)

A broad and expanding range of materials can be produced by atomic layer deposition at relatively low temperatures, including both oxides and metals. For many applications of interest, however, it is desirable to grow more tailored and complex materials such as semiconductors with a certain doping, mixed oxides, and metallic alloys. How well such mixed materials can be accomplished with atomic layer deposition requires knowledge of the conditions under which the resulting films will be mixed, solid solutions, or laminated. The growth and lamination of zinc oxide and tin oxide is studied here by means of the extremely surface sensitive technique of low energy ion scattering, combined with bulk composition and thickness determination, and x-ray diffraction. At the low temperatures used for deposition (150 °C), there is little evidence for atomic scale mixing even with the smallest possible bilayer period, and instead a morphology with small ZnO inclusions in a SnO{sub x} matrix is deduced. Postannealing of such laminates above 400 °C however produces a stable surface phase with a 30% increased density. From the surface stoichiometry, this is likely the inverted spinel of zinc stannate, Zn{sub 2}SnO{sub 4}. Annealing to 800 °C results in films containing crystalline Zn{sub 2}SnO{sub 4}, or multilayered films of crystalline ZnO, Zn{sub 2}SnO{sub 4}, and SnO{sub 2} phases, depending on the bilayer period.

• OSTI ID: 22489810
• Journal Information: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films, Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films Journal Issue: 2 Vol. 34; ISSN 0734-2101; ISSN JVTAD6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
ALLOYS
ANNEALING
DENSITY
DEPOSITION
FILMS
SOLID SOLUTIONS
SPINELS
SURFACES
THICKNESS
TIN OXIDES
X-RAY DIFFRACTION
ZINC
ZINC OXIDES