Research Projects

The rapid advancement of two-dimensional (2D) semiconductor materials has generated significant interest in their application for next-generation electronic and photonic devices. With properties such as atomic-scale thickness, high carrier mobility, mechanical flexibility, and tunable bandgap, these materials offer a promising alternative to traditional silicon-based technologies. However, a long-standing bottleneck in this field is the integration of high-quality, ultrathin dielectric layers on 2D materials without compromising their delicate surfaces. Traditional dielectric deposition techniques such as atomic layer deposition (ALD) and chemical vapor deposition (CVD) are incompatible with 2D materials, as they require high temperatures, aggressive chemical precursors, and vacuum systems, leading to defective interfaces, high leakage currents, and degraded device performance. This persistent challenge inspired the search for alternative dielectric integration strategies capable of delivering ultrathin, amorphous or crystalline, high-k dielectrics with minimal process-induced damage. Recent advancements in the use of liquid metals (LMs) as self-forming oxide templates presented a unique opportunity. Native oxides that spontaneously form on liquid metal surfaces, such as Gallium (Ga), Indium (In), or eutectic alloys, exhibit atomically smooth, ultrathin (~1–5 nm) profiles and can be mechanically separated and transferred onto various substrates. Building on these early insights, we recognized that by tuning the liquid metal composition and deposition conditions, it is possible to selectively synthesize crystalline 2D oxides (C2DOs) with tailored electronic and optical properties. This approach not only overcomes the limitations of conventional dielectrics but also enables the fabrication of p–n junction diodes by integrating p-type (e.g., TeO2) and n-type (e.g., WS2, Ga2O3) semiconducting oxides. Crystalline dielectrics inherently possess superior electrical properties compared to their amorphous counterparts, including higher breakdown strength, lower interface trap densities, and improved leakage performance, making them ideal candidates for low-power, high-performance nanoelectronic and optoelectronic devices. Our early exploratory studies demonstrated the feasibility and robustness of this approach, laying the foundation for this comprehensive proposal. By systematically developing a crystalline 2D oxide material library, integrating them into scalable device architectures, and benchmarking their electrical and optical performance against existing technologies. The outcomes of this research are expected to enable transformative advances in 2D electronics, photodetectors, and quantum devices, while also contributing to the India Semiconductor Mission (ISM).