Gas-Phase Alloying of Sulfur-Selenium Dielectrics with High Ionic Mobility for Next-Generation Electronics

The increasing demands of future electronics necessitate the development of innovative dielectric materials that can meet the diverse requirements of advanced electronic applications. Enhanced electrostatic control in ultrascaled transistors requires dielectrics with higher dielectric constants, while improved power efficiency can be achieved through effective dielectric polarization control. Additionally, the development of wearable and implantable devices necessitates flexible dielectrics for use as substrates and gates. In-memory computing also relies on the emergent memristive properties of dielectrics. To address these diverse requirements, we investigate sulfur-selenium (S-Se) alloy as a dielectric material for advanced electronic applications. By employing an innovative chemical vapor deposition (CVD) technique, we produce ultrathin, crystalline S-Se alloy films with uniform large-scale morphology. Experimental diffraction analysis and materials modeling reveal a modified lattice structure in the alloy, which enhances ionic mobility. This characteristic is confirmed through electrochemical impedance spectroscopy and utilized to fabricate memristive devices with outstanding performance. Our results highlight the potential of gas-phase alloying to develop dielectrics with multifaceted functionality, robust mechanical stability, and precise morphology control, thereby paving the way for the integration of these materials in next-generation electronic devices.