Demonstration of the DC-Kerr effect in silicon-rich nitride

Area of Science:

• Materials Science
• Optoelectronics
• Nonlinear Optics

Background:

• Nonlinear optical effects are crucial for advanced photonic devices.
• Silicon-rich nitride (SRN) is a material with potential for integrated photonics.
• Characterizing nonlinear properties is essential for device development.

Purpose of the Study:

• To demonstrate the DC-Kerr effect in plasma-enhanced chemical vapor deposition (PECVD) silicon-rich nitride (SRN).
• To quantify the third-order nonlinear susceptibility (χ(3)) of PECVD SRN.
• To evaluate PECVD SRN as a material for optical phase shifters in CMOS processes.

Main Methods:

• Utilizing the DC-Kerr effect for nonlinear characterization.
• Employing spectral shift versus applied voltage measurements.
• Using racetrack resonators to measure nonlinear susceptibilities.

Main Results:

• Demonstrated the DC-Kerr effect in PECVD SRN.
• Measured a high third-order nonlinear susceptibility (χ(3)) of (6±0.58)×10⁻¹⁹ m²/V².
• Achieved a χ(3) value greater than that of silicon.

Conclusions:

• PECVD SRN possesses a significant nonlinear optical response.
• The measured χ(3) indicates potential for efficient optical phase shifting.
• PECVD SRN is a viable material for low-thermal-budget photonic integrated circuits within CMOS flows.