Stress-Dependent Optical Extinction in Low-Pressure Chemical Vapor Deposition Silicon Nitride Measured by Nanomechanical Photothermal Sensing.

ABSTRACT: Understanding optical absorption in silicon nitride is crucial for cutting-edge technologies like photonic integrated circuits, nanomechanical photothermal infrared sensing and spectroscopy, and cavity optomechanics. Yet, the origin of its strong dependence on the film deposition and fabrication process is not fully understood. This Letter leverages nanomechanical photothermal sensing to investigate optical extinction κ_ext at a 632.8 nm wavelength in low-pressure chemical vapor deposition (LPCVD) SiN strings across a wide range of deposition-related tensile stresses (200-850 MPa). Measurements reveal a reduction in κ_ext from 10³ to 10¹ ppm with increasing stress, correlated to variations in Si/N content ratio. Within the band-fluctuations framewo

SUBMITTER: Kanellopulos K 

PROVIDER: S-EPMC11403763 | biostudies-literature | 2024 Sep

REPOSITORIES: biostudies-literature