Metal electrodes transfer using polycarbonate for the fabrication of molybdenum disulfide semiconductor devices

Fabricating high-performance 2D nanosheet-based semiconductor devices faces challenges due to the structural damage caused by traditional metal electrode deposition processes. This study introduces a novel polycarbonate (PC) assisted metal electrode transfer technique that effectively preserves the structural and electronic properties of MoS₂ nanosheets. Using the proposed method, metal electrodes are successfully transferred onto MoS₂ nanosheets via the shadow mask process (20 μm channel) and photolithography (8 μm and 3 μm channels) for photodetector and field-effect transistor (FET) fabrication, respectively. Photodetectors fabricated with transferred electrodes exhibit stable current-voltage characteristics, with the shadow mask-based photodetector achieving a maximum photoresponsivity of 0.73 µA/W under a 450 nm laser at 10 V bias. The photolithography-based photodetector demonstrates higher photoresponsivity of 3.62 mA/W due to enhanced light absorption. Additionally, the FETs fabricated using the PC transfer process show NMOS behavior with electron mobility values of up to 0.17 cm²/V s during reverse sweeps. PC covered FETs further improve performance under ambient conditions, achieving electron mobility up to 0.517 cm²/V s and stable switching current ratios. These findings underscore the PC assisted electrode transfer method's advantages in maintaining material integrity, achieving stable device performance, and offering scalability for large-scale applications.