Doping‐Free Monolithic 2D CMOS Logic by Fermi‐Level Engineering via Tellurium Buffer‐Layer

This is the authors' abstract. We don't add key points for this paper.

2D semiconductors hold great potential for post-Moore complementary-metal-oxide semiconductor (CMOS) technology. However, the doping-free CMOS logic circuits utilizing identical 2D semiconductors pose a critical challenge in achieving efficient metal-dependent polarity modulation, predominantly due to interface defects and Fermi-level pinning (FLP) caused by metallization-induced chemical interactions. Here, a doping-free CMOS fabrication strategy is reported that employs a tellurium (Te) buffer-layer-assisted thermal deposition of the same metal to enable complementary polarity transport on the same 2D semiconductor. By introducing a sacrificial Te buffer-layer onto the 2D semiconductors prior to the thermal deposition of metal and subsequent controlled annealing for its complete removal, the created quasi-van der Waals (vdW) metal-semiconductor interface achieves work-function-dependent polarity control. This contrasts with conventional deposited contacts that lead to FLP-dominated n-type behavior. By utilizing high-work-function Au metal to modulate the polarity of the same 2D semiconductor, the fabricated CMOS inverter realizes a voltage gain of 165 at a 5 V bias and a 95% total noise margin. Importantly, this technique is readily applicable to scalable, industry-compatible CMOS devices manufacturing while concurrently optimizing interfacial charge transport characteristics, demonstrating back-end-of-line (BEOL) compatibility. This study establishes a foundational framework for 3D monolithic integration through Fermi-level engineering, paving the way for next-generation vertically integrated nanoelectronics.