Achieving High-Quality Sn-Pb Perovskite Films on Complementary Metal-Oxide-Semiconductor-Compatible Metal/Silicon...

Area of Science:

• Materials Science
• Optoelectronics
• Semiconductor Physics

Background:

• Tin-lead (Sn-Pb) perovskites offer potential for near-ultraviolet-visible-near-infrared light sensing, but integration with silicon electronics is hindered by film quality issues.
• High surface roughness and pinholes in Sn-rich perovskites lead to high dark current and poor uniformity, limiting their use in photodiodes and imaging.

Purpose of the Study:

• To develop high-quality Sn-Pb perovskite films on metal/silicon substrates for photodiodes and imaging.
• To enable direct integration of perovskite optoelectronics with complementary metal-oxide semiconductor (CMOS) and silicon electronics.

Main Methods:

• Room-temperature crystallization technique to control film formation kinetics in Sn-rich binary perovskites.
• Experimental and theoretical studies of the crystallization mechanism to tune nanocrystal density and location.
• Fabrication and characterization of perovskite photodiodes and a 6x6 pixel array on CMOS-compatible metal/silicon substrates.

Main Results:

• Achieved smooth, dense, and pinhole-free perovskite films with preferred orientation and reduced trap density.
• Demonstrated perovskite photodiodes with significantly reduced dark current and improved uniformity.
• Self-powered devices exhibited high responsivity (0.2 A/W at 940 nm), a 100 dB dynamic range, and a fast fall time (2.27 μs).
• Successfully demonstrated a 6x6 pixel photodiode array for imaging applications.

Conclusions:

• Room-temperature crystallization is effective for producing high-quality Sn-Pb perovskites on metal/silicon substrates.
• The developed perovskite photodiodes outperform silicon-based sensors in key performance metrics.
• This work advances the understanding of Sn-Pb perovskite crystallization and facilitates integration with silicon electronics for next-generation optoelectronic devices.