Noninvasive and Contactless Characterization of Electronic Properties at the Semiconductor/Dielectric Interface Using...

Area of Science:

• Materials Science
• Solid State Physics
• Optoelectronics

Background:

• Optical second-harmonic generation (SHG) is a valuable tool for surface and interface analysis.
• Characterizing semiconductor/dielectric interfaces is crucial for electronic device performance.
• Existing methods may be destructive or lack quantitative accuracy.

Purpose of the Study:

• To develop a non-destructive, contactless SHG-based metrology for semiconductor/dielectric interfaces.
• To quantitatively measure conduction band offset and interface charge densities.
• To qualitatively assess interface states and their variations.

Main Methods:

• Demonstration of a novel SHG-based characterization technique.
• Development of an optical setup for time-dependent second-harmonic generation (TDSHG) monitoring.
• Utilizing a numerical solver with carrier dynamics to model experimental data.

Main Results:

• Successful measurement of conduction band offset and quantitative evaluation of charge densities at the Si/HfO2 interface.
• Extraction of interface-trapped charge type (donor/acceptor).
• Qualitative analysis of interface state density (Dit) variations and band bending.

Conclusions:

• The SHG-based method provides a reliable, non-destructive approach for semiconductor/dielectric interface characterization.
• TDSHG temporal characteristics correlate with interface charge trapping dynamics.
• The technique enables accurate extraction of electronic properties at interfaces.