Atomic Layer Deposition of Crystalline MoS2 Thin Films: New Molybdenum Precursor for Low‐Temperature Film Growth. Issue 18 (30th March 2017)

• Record Type: Journal Article
• Authors: Mattinen, Miika; Hatanpää, Timo; Sarnet, Tiina; Mizohata, Kenichiro; Meinander, Kristoffer; King, Peter J.; Khriachtchev, Leonid; Räisänen, Jyrki; Ritala, Mikko; Leskelä, Markku
• Is Part Of: Advanced materials interfaces. Volume 4:Issue 18(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-03-30
• Subjects: 2D materials -- atomic layer deposition -- MoS2 -- thin films; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.201700123
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract : Molybdenum disulfide (MoS2 ) is a semiconducting 2D material, which has evoked wide interest due to its unique properties. However, the lack of controlled and scalable methods for the production of MoS2 films at low temperatures remains a major hindrance on its way to applications. In this work, atomic layer deposition (ALD) is used to deposit crystalline MoS2 thin films at a relatively low temperature of 300 °C. A new molybdenum precursor, Mo(thd)3 (thd = 2, 2, 6, 6‐tetramethylheptane‐3, 5‐dionato), is synthesized, characterized, and used for film deposition with H2 S as the sulfur precursor. Self‐limiting growth with a low growth rate of ≈0.025 Å cycle −1, straightforward thickness control, and large‐area uniformity are demonstrated. Film crystallinity is found to be relatively good considering the low deposition temperature, but the films have significant surface roughness. Additionally, chemical composition as well as optical and wetting properties are evaluated. MoS2 films are deposited on a variety of substrates, which reveal notable differences in growth rate, surface morphology, and crystallinity. The growth of crystalline MoS2 films at comparably low temperatures by ALD contributes toward the use of MoS2 for applications with a limited thermal budget. Abstract : Crystalline molybdenum disulfide (MoS2 )thin films are deposited by atomic layer deposition (ALD) at 300 °C. A new Mo precursor, Mo(thd)3, is synthesized, characterized, and used to deposit MoS2 with H2 S. Self‐limiting film growth offers precise control over film thickness and excellent uniformity. Morphology, crystallinity, and chemical composition as well as optical and wetting properties of the deposited films are examined.