This paper presents a technology for fabricating microstructures based on carbon nanowalls (CNWs) integrated on silicon nitride (${\text{SiN}}_{\mathrm{x}}$) waveguides. The step-by-step fabrication process is described, including chemical mechanical planarization, deposition of molybdenum contacts, selective etching of the upper ${\mathrm{SiO}}_{\mathrm{x}}$ buffer layer relative to ${\text{SiN}}_{\mathrm{x}}$, and plasma-enhanced chemical vapor deposition of CNWs. The photothermoelectric response of the structures was studied in the C-band, near the $1.55\mathrm{\mu }\mathrm{m}$ wavelength. The results demonstrate that the primary mechanism of the response to the laser emission is the Seebeck effect, providing a maximum sensitivity of $0.037\mathrm{V}/\mathrm{W}$ without thermal degradation of the CNWs. Furthermore, the amplitude-frequency response of the structures corresponds to that of a fourth-order Butterworth filter with a cutoff frequency of 13.4 kHz. The utilization of the Joule-heating-assisted enhancement allows for a 21.4-fold increase in the output signal amplitude, but it also reduces the bandwidth. These findings highlight the prospects for CNWs in integrated photonics for near-infrared emission detection.

Close

PrevNext

View figure in article

• Integrated optics
• Optical quantum information processing
• Optoelectronics
• Carbon-based materials
• Nanostructures
• Thermoelectrics
• Waveguides
• Infrared techniques