Interface Growth and Engineering of 2D Semiconductors

In this presentation, I will focus on the critical role of interface engineering in the growth and integration of materials in contact with 2D semiconductors. Given the potential of 2D semiconductors as next-generation logic channels and for Monolithic 3D integration, understanding and optimizing these interfaces is paramount. Achieving high-quality interfaces on 2D semiconductors without the use of plasma or seed layers presents significant challenges. The interface between the 2D semiconductor and the deposited thin films often acts as a trap, significantly affecting the performance of the semiconductor. Additionally, conventional plasma or high-temperature processes tend to damage the delicate mono or bilayer structures of 2D materials.<br/>Firstly, I will discuss our breakthroughs in selective area ALD (AS-ALD) processes, particularly on laterally heterogeneous 2D semiconductor surfaces. Our findings highlight the importance of the physisorption of ALD precursors, which is essential for achieving selective deposition patterns, thereby expanding the applicability of AS-ALD beyond traditional limits and potentially forming high-quality interfaces between ALD materials and 2D semiconductors.<br/>Secondly, the presentation will explore the vertical, hetero, and epitaxial growth of 2D and 3D materials, with a particular emphasis on the 2D/3D interface within van der Waals epitaxial growth. This research underscores the potential and understanding of utilizing van der Waals epitaxy for forming interfaces between 2D and 3D materials, paving the way for more reliable and efficient integration of 2D semiconductors in advanced electronic applications.<br/>Lastly, I will briefly introduce the recent advancements in low-temperature MOCVD growth and device processing in my group, including new 2D semiconductor materials beyond TMDs.