Read on to know the strategy that can protect sensitive oxide-semiconductors, achieve high on-state current and low subthreshold swing in scalable 3D transistor architectures.
As transistor miniaturization approaches physical limits, 3D stacking of back-end-of-line (BEOL) compatible transistors promises enhanced performance for low-power electronics. Advanced architectures, such as gate-all-around nanosheets, typically rely on a channel-first process, where dielectrics are deposited directly onto the semiconductor channel. For amorphous oxide semiconductors, this approach can introduce defects or structural changes, degrading electrical performance. Post-deposition annealing can mitigate some damage but often impacts other device metrics.
To address this challenge, researcher at Cornell University have developed a channel-last gate-all-around transistor design. In this approach, the transistor channel is introduced after dielectric deposition, preventing damage to sensitive oxide-semiconductor materials. The resulting devices are self-aligned and demonstrate high on-state current exceeding 1 mA/μm, along with low subthreshold swing, reaching a minimum of 63 mV/dec which is achieved without any post-deposition processing.
This channel-last strategy provides a scalable and general method for integrating atomic-layer-deposited channels into advanced transistor architectures. By preserving electrical integrity while remaining compatible with BEOL processes, it enables the realization of low-power, high-performance three-dimensional electronics.
Key features of the research include:
- Channel-last design prevents dielectric-induced defects in oxide-semiconductor transistors.
- High on-state current (>1 mA/μm) and low subthreshold swing (63 mV/dec) achieved without post-deposition annealing.
- Compatible with back-end-of-line processes, enabling scalable 3D transistor integration.
This innovation opens a pathway for robust, high-performance and low-power transistors, shaping the future of three-dimensional electronic devices.
