Toward Phonon-Limited Transport in Two-Dimensional Transition Metal Dichalcogenides by Oxygen-Free Fabrication

are relatively stable in air, we show that even short-term ambient exposure can degrade their performance. We identify oxygen as a crucial factor in limiting transistor performance through irreversible chemisorption. This study emphasizes the criticality of avoiding oxygen exposure and offers guidance for device manufacturing that impacts fundamental research and practical applications of 2D materials.