Addressing Mobility Overestimation in Short-Channel IGZO TFTs Using the Gated Van der Pauw Method
Woo-Seok Lee1,2, Jaeho Lee1,2, Amarja Katware1,2
1Department of Materials Science and Engineering, Inha University, Incheon 22212, Republic of Korea.
ACS Applied Materials & Interfaces
|November 11, 2024
Summary
Accurately measuring field-effect mobility in short-channel indium gallium zinc oxide (IGZO) thin-film transistors (TFTs) is challenging due to contact resistance. The gated van der Pauw method precisely extracts sheet resistance, enabling accurate mobility evaluation.
Area of Science:
- Materials Science
- Semiconductor Physics
- Device Engineering
Background:
- Indium gallium zinc oxide (IGZO) thin-film transistors (TFTs) are crucial for advanced electronics.
- Accurate field-effect mobility determination is vital for optimizing IGZO TFT performance.
- Short channel lengths (< few micrometers) in IGZO TFTs complicate mobility evaluation due to significant contact resistance effects.
Purpose of the Study:
- To develop a precise method for extracting sheet resistance in short-channel IGZO TFTs.
- To overcome the challenge of contact resistance influencing mobility measurements.
- To enable accurate assessment of intrinsic channel characteristics and device performance.
Main Methods:
- Employed the gated van der Pauw (gVDP) method.
- The gVDP method allows for contact-resistance-independent extraction of sheet resistance.
- Applied to IGZO thin-film transistors with short channel lengths.
Main Results:
- Successfully extracted sheet resistance independently of contact resistance.
- Mitigated the overestimation of charge behavior and mobility in IGZO TFTs.
- Provided accurate intrinsic channel mobility values for short-channel devices.
Conclusions:
- The gated van der Pauw method is essential for precise sheet resistance extraction in short-channel IGZO TFTs.
- This approach prevents inaccurate parameter overestimation, ensuring reliable device characterization.
- Enables accurate prediction of maximum performance for next-generation short-channel electronic devices.
Keywords:
contact resistancefield-effect mobilitygated van der Pauwindium−gallium−zinc-oxide thin-film transistorssheet resistanceMore Related Videos
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