Thickness dependent structural, electronic, and optical properties of Ge nanostructures

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Germanium (Ge) thin films are crucial for semiconductor applications.
• Understanding the impact of nanostructure formation on Ge properties is essential for device optimization.

Purpose of the Study:

• To investigate the structural, optical, and electronic properties of Ge thin films.
• To correlate these properties with film thickness, nanostructure, and quantum confinement effects.

Main Methods:

• Electron beam evaporation for Ge thin film deposition.
• Raman spectroscopy, GIXRD, AFM, UV-Vis absorption, PES, PL, and resistivity measurements.

Main Results:

• Raman spectra indicate nanostructure formation and quantum confinement, with peak shifts correlating to film thickness.
• Optical absorption spectra reveal size-dependent band gaps, larger than bulk Ge, attributed to quantum confinement.
• AFM, PES, PL, and resistivity measurements support the influence of crystallinity and quantum confinement on film properties.

Conclusions:

• Ge thin film properties are significantly influenced by nanostructure and quantum confinement effects.
• Film thickness plays a critical role in the observed structural, optical, and electronic property variations.
• These findings provide insights into tailoring Ge thin films for advanced electronic and optoelectronic applications.