Single crystal hybrid perovskite field-effect transistors

Area of Science:

• Materials Science
• Condensed Matter Physics
• Device Physics

Background:

• Hybrid organic-inorganic perovskites have driven advances in photovoltaics, photodetection, and light emission.
• Perovskite-based field-effect transistors (FETs) are less explored due to sensitivity to surface defects in polycrystalline films.
• Achieving high-quality perovskite crystals is crucial for electronic device applications.

Purpose of the Study:

• To develop a method for synthesizing high-quality methylammonium lead halide perovskite (MAPbX₃) single crystals.
• To integrate these high-quality crystals into ambipolar transistors.
• To achieve record field-effect mobility in perovskite-based FETs.

Main Methods:

• Employed a spatially-confined inverse temperature crystallization strategy.
• Synthesized micrometre-thin single crystals of MAPbX₃ (X = Cl, Br, I) with controlled surface properties.
• Fabricated ambipolar transistors using the synthesized MAPbX₃ single crystals.

Main Results:

• Achieved sub-nanometer surface roughness and minimal surface contamination in MAPbX₃ single crystals.
• Demonstrated record room-temperature field-effect mobility of 4.7 cm² V⁻¹ s⁻¹ (p-channel) and 1.5 cm² V⁻¹ s⁻¹ (n-channel).
• Obtained high on-off ratios (10⁴–10⁵) and low turn-on voltages in the fabricated transistors.

Conclusions:

• The inverse temperature crystallization method yields high-quality perovskite single crystals suitable for electronic devices.
• High-performance ambipolar transistors based on MAPbX₃ single crystals were successfully fabricated.
• This work enables the integration of hybrid perovskite crystals into printed, flexible, and transparent electronic applications.