Ultrasonic Spray Pyrolysis Deposited Copper Sulphide Thin Films for Solar Cell Applications

Area of Science:

• Materials Science
• Solid State Physics
• Nanotechnology

Background:

• Copper sulfide (Cu S) is a promising semiconductor material for various electronic and optoelectronic applications.
• Controlling the phase and properties of Cu S thin films is crucial for device performance.

Purpose of the Study:

• To investigate the synthesis of polycrystalline copper sulfide thin films using ultrasonic spray pyrolysis.
• To characterize the structural, optical, and electrical properties of Cu S films deposited at different substrate temperatures.
• To explore the influence of substrate temperature on the phase, morphology, and properties of Cu S thin films.

Main Methods:

• Ultrasonic spray pyrolysis using aqueous solutions of copper chloride and thiourea.
• Structural characterization via X-ray diffraction (XRD).
• Morphological analysis using scanning electron microscopy (SEM) and atomic force microscopy (AFM).
• Optical properties determined by optical absorption measurements.
• Electrical properties assessed through current-voltage (I-V) and Hall effect measurements.

Main Results:

• XRD analysis confirmed single or mixed phase polycrystalline nature with hexagonal covellite and cubic digenite structures.
• Crystalline phase and optical band gap varied with substrate temperature (2.07 eV for CuS, 2.50 eV for Cu1.765S, 2.28 eV for Cu1.765S-Cu2S).
• AFM revealed well-adhered spherical nanosized particles, and contact angle measurements indicated hydrophobic films.
• Hall effect measurements confirmed p-type conductivity for all deposited Cu S films.

Conclusions:

• Ultrasonic spray pyrolysis is an effective method for synthesizing polycrystalline Cu S thin films with tunable properties.
• Substrate temperature significantly influences the crystalline phase and optical band gap of Cu S films.
• The synthesized Cu S thin films exhibit promising characteristics for potential applications in electronic devices.