High-Performance Planar-Type Photodetector Based on Hot-Pressed CsPbBr₃ Wafer

Area of Science:

• Materials Science
• Optoelectronics
• Semiconductor Physics

Background:

• Common CsPbBr3 single crystal growth methods, such as melt and solution techniques, face challenges including high costs and poor shape control.
• Developing efficient and controllable methods for CsPbBr3 crystal fabrication is crucial for advanced optoelectronic applications.

Purpose of the Study:

• To introduce a facile hot-pressed (HP) approach for preparing CsPbBr3 wafers.
• To investigate the impact of HP temperature on the phase purity and properties of CsPbBr3 wafers.
• To evaluate the performance of photodetectors fabricated using HP-CsPbBr3 wafers for weak light detection.

Main Methods:

• A hot-pressing (HP) technique was employed to synthesize CsPbBr3 wafers.
• The influence of varying HP temperatures on CsPbBr3 wafer characteristics was systematically studied.
• Planar-type photodetectors were fabricated using the optimized HP-CsPbBr3 wafers.

Main Results:

• The optimal HP temperature for achieving phase-pure, shape-regular, and dense CsPbBr3 wafers was determined to be 150 °C.
• CsPbBr3 wafer-based photodetectors demonstrated an ultrasensitive response to weak light.
• Key performance metrics for the photodetectors included a responsivity of 19.79 A W⁻¹, an external quantum efficiency of 4634%, and a detectivity of 2.14 × 10¹³ Jones.
• The devices exhibited a fast response speed with a rise time of 40.5 μs and a fall time of 10.0 μs.

Conclusions:

• The hot-pressed (HP) method provides a facile and effective route for fabricating high-quality CsPbBr3 wafers.
• The optimized HP-CsPbBr3 wafers enable the development of highly sensitive and fast-responding photodetectors for weak light detection applications.
• This work presents a promising advancement in CsPbBr3-based optoelectronic device technology.