Enhanced Red Emission from Amorphous Silicon Carbide Films via Nitrogen Doping

Area of Science:

• Materials Science
• Solid State Physics
• Optoelectronics

Background:

• Amorphous silicon carbide (a-SiC:H) films are crucial for optoelectronic devices.
• Achieving efficient red photoluminescence (PL) in these materials remains a challenge.
• Defect-related non-radiative recombination often limits luminescence efficiency.

Purpose of the Study:

• To investigate the effect of nitrogen doping on red photoluminescence (PL) in silicon-rich amorphous silicon carbide (a-SiC_x) films.
• To understand the underlying mechanisms responsible for PL enhancement.
• To correlate structural and bonding changes with optical properties.

Main Methods:

• Nitrogen doping of Si-rich a-SiC_x films.
• Photoluminescence (PL) spectroscopy for optical analysis.
• Raman spectroscopy to study film structure.
• Fourier transform infrared absorption (FTIR) spectroscopy to analyze bonding configurations.

Main Results:

• A significant enhancement of red PL intensity (over three times) was observed with increasing nitrogen doping concentration.
• Raman and FTIR analyses revealed the substitution of weak Si-Si bonds with stronger Si-N bonds.
• A correlation was established between the reduction of non-radiative recombination centers and the observed PL enhancement.

Conclusions:

• Nitrogen doping is an effective strategy to enhance red photoluminescence in Si-rich a-SiC_x films.
• The improved PL is attributed to the passivation of non-radiative defects by Si-N bond formation.
• This work provides insights into optimizing a-SiC_x materials for optoelectronic applications.