Centimeter‐Scale and Visible Wavelength Monolayer Light‐Emitting Devices. (2nd December 2019)

• Record Type: Journal Article
• Authors: Cho, Joy; Amani, Matin; Lien, Der‐Hsien; Kim, Hyungjin; Yeh, Matthew; Wang, Vivian; Tan, Chaoliang; Javey, Ali
• Is Part Of: Advanced functional materials. Volume 30:Number 6(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-12-02
• Subjects: chemical vapor deposition -- electroluminescence -- monolayer display -- transition metal dichalcogenide -- visible emission -- WS2; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201907941
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Monolayer 2D transition metal dichalcogenides (TMDCs) have shown great promise for optoelectronic applications due to their direct bandgaps and unique physical properties. In particular, they can possess photoluminescence quantum yields (PL QY) approaching unity at the ultimate thickness limit, making their application in light‐emitting devices highly promising. Here, large‐area WS2 grown via chemical vapor deposition is synthesized and characterized for visible (red) light‐emitting devices. Detail optical characterization of the synthesized films is performed, which show peak PL QY as high as 12%. Electrically pumped emission from the synthetic WS2 is achieved utilizing a transient‐mode electroluminescence device structure, which consists of a single metal–semiconductor contact and alternating gate fields to achieve bipolar emission. Utilizing this aforementioned structure, a centimeter‐scale (≈ 0.5 cm 2 ) visible (640 nm) display is demonstrated, fabricated using TMDCs to showcase the potential of this material system for display applications. Abstract : A centimeter‐scale, visible wavelength light‐emitting display is demonstrated utilizing a tungsten disulfide monolayer synthesized via chemical vapor deposition. Operated in the transient mode, the device exhibits bright red emission from an emission layer measuring 0.7 nm in thickness. This work highlights the potential use of monolayer semiconductors in ultrathin displays, taking advantage of their high luminescence quantum yields.