Unravelling chemical etchant influences during assisted wet-transfer to obtain high quality MoS2 atomic layers

• DOI: 10.1016/j.apsusc.2024.160331
• Publication Date: 2024-05-27T15:44:23Z
• Authors: Animesh Pratap Singh; Han Xu; Amir Ghiami; Songyao Tang; Zhaodong Wang; Holger Kalisch; Susanne Hoffmann-...; Alwin Daus; Sven Ingebrandt; Andrei Vescan; Vivek Pachauri

Two-dimensional (2D) MoS2 is an emerging alternative to traditional semiconductors, overcoming scaling limits in device fabrication. Ongoing efforts realize the full potential of 2D CMOS back-end-of-line integration encounters notable challenges due synthesis such materials requiring high temperature growth substrates and a transfer step. Consequently, lattice preservation atomic layers during from substrate target crucial for fabrication system integration. This work, investigates impact commonly used chemical etchant potassium hydroxide (KOH) on poly(methylmethacrylate) (PMMA) assisted wet-transfer process sapphire substrates. A systematic experimental framework involving Raman spectroscopy, Atomic Force Microscopy (AFM), Optical Microscopy, X-ray Photoelectron Spectroscopy (XPS) was employed comparative evaluation upon transfer. While investigations highlight relation concentration exposure time be deterministic factors, topographic spectroscopic evidence corroborate role K+ ions etching oxidation at higher concentrations affecting quality. Thorough characterizations process, while following quality this provides information selection achieve shorter with minimal material