Novel channel-last integration of ALD MoS 2 into stacked channel FETs on 300mm wafers

We report, for the first time, the integration of ALD-grown MoS2 into stacked channel transistors via a novel channel-last integration scheme. Our approach provides many advantages and opportunities concerning channel formation, enhanced delamination control, contact optimization, reduced contamination risks, and the ability to reuse process modules of existing Si GAA routes. To assess such a process flow, we first developped and optimized ALD MoS2 films. We also optimized source/drain contacts using back-gated MoS2 transistors with down to 15 nm widths. Niobium contacts delivered an ION/IOFF ratio up to 10⁴ and outperformed titanium counterparts with up to 28× Iₒₙ enhancement. Then, we validated key modules of our novel channel-last integration, overcoming most of the technological roadblocks limiting the 2D TMD integration into advanced CMOS. Finally, TCAD simulations were performed to optimize our architecture and draw some perspectives.