High Performance Photodiode Based on p-Si/Copper Phthalocyanine Heterojunction

Area of Science:

• Materials Science
• Optoelectronics
• Semiconductor Devices

Background:

• Hybrid organic-inorganic (HOI) photodiodes combine the benefits of organic and inorganic materials.
• They offer advantages like compatibility with silicon technology, low cost, and high photosensitivity.
• HOI photodiodes show significant potential for various applications.

Purpose of the Study:

• To fabricate and characterize red light sensitive HOI photodiodes.
• To investigate the impact of copper phthalocyanine (CuPc) layer thickness on device performance.
• To derive an analytical expression for photocurrent dependence on layer thickness.

Main Methods:

• Fabrication of p-Si/copper phthalocyanine (CuPc) heterojunction photodiodes.
• Characterization of device performance under varying CuPc layer thicknesses.
• Optical and electrical measurements to determine photoresponsivity and quantum efficiency.

Main Results:

• An optimal CuPc layer thickness of approximately 30 nm was identified.
• An analytical expression was derived to model the thickness-dependent saturation photocurrent.
• A photoresponsivity of 0.35 A/W and external quantum efficiency of 70% were achieved at 655 nm with a 9 V reverse bias.

Conclusions:

• The study successfully demonstrates red light sensitive HOI photodiodes with optimized CuPc layer thickness.
• The findings provide a method for understanding and optimizing HOI photodiode performance.
• These devices exhibit promising characteristics for optoelectronic applications.