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Mitigating Hysteresis in Amorphous Tellurium Selenium Oxide P-Type Field-Effect Transistor Via Fermi-Level Tuning
Zhidong Tang1, Ting Liu1, Jianshi Tang1
1School of Integrated Circuits, Beijing Advanced Innovation Center for Integrated Circuits, BNRist, Tsinghua University, Beijing100084, China.
Nano Letters
|August 12, 2026
Summary
This study introduces a Fermi-level tuning strategy to improve p-type field-effect transistors (p-FETs) using amorphous tellurium selenium oxide. Aluminum oxide gate dielectrics significantly reduce hysteresis and enhance mobility in these crucial components for advanced electronics.
Area of Science:
- Materials Science
- Semiconductor Physics
- Electronics Engineering
Background:
- High-performance p-type oxide semiconductors are essential for complementary logic in advanced applications like 3D integration.
- Amorphous tellurium selenium oxide (TeSeOx) p-type field-effect transistors (p-FETs) show promise but suffer from hysteresis and instability.
- Existing n-type oxide semiconductors have advanced, but p-type counterparts lag behind.
Purpose of the Study:
- To develop a Fermi-level tuning strategy to suppress hysteresis in TeSeOx p-FETs.
- To investigate the impact of different gate oxide materials (HfO2 vs. Al2O3) on device performance and stability.
- To enhance the operational stability and field-effect mobility of p-type oxide semiconductors for practical applications.
Main Methods:
- Implemented a Fermi-level tuning strategy by modulating the energetic alignment between the channel Fermi level (EF) and defect bands in the gate oxide (GOX).
- Conducted a comparative analysis using HfO2 and Al2O3 as gate oxide materials.
- Fabricated and characterized amorphous TeSeOx p-FETs with different gate dielectrics.
Main Results:
- Al2O3 as the gate oxide effectively mitigates instabilities caused by charge trapping.
- Al2O3-gated p-FETs demonstrated substantially suppressed hysteresis compared to HfO2-gated devices.
- Despite a lower dielectric constant, Al2O3-gated p-FETs exhibited enhanced field-effect mobility, challenging conventional scaling theories.
Conclusions:
- The proposed Fermi-level tuning strategy effectively suppresses hysteresis and enhances operational stability in TeSeOx p-FETs.
- Al2O3 is a superior gate dielectric material for TeSeOx p-FETs, offering improved performance and stability over HfO2.
- These findings pave the way for high-performance, stable p-type oxide semiconductors crucial for next-generation electronic devices and monolithic 3D integration.
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