Cryogenic coating technique applications in the fabrication of plasmonic AuNPs/n-Si/Al photodetectors

Kose Y. E., Manır M., Tomakin M., Genç G., Nevruzoğlu V.

EUROPEAN PHYSICAL JOURNAL PLUS, cilt.141, sa.9, 2026 (SCI-Expanded, Scopus)

Özet

In this study, Au nanoparticles were coated on glass and n-Si (111) surfaces at different substrate temperatures (300-100 K) in a vacuum environment (10-6 Torr) using the cryogenic coating method. In the first stage of the study, the effect of the new coating method on the produced Au layer was examined. In this direction, AuNPs/glass samples were produced and their characteristic properties were examined experimentally. When the obtained field-emission scanning electron microscopy (FESEM) images were examined, it was seen that the Au layer produced at 230 K substrate temperature consisted of equal-sized clusters. This result showed that the Au film formed on the glass surface cooled at 230 K by the soliton growth mechanism. Then, the SPR phenomenon was detected by optical measurements in AuNPs/Glass binary structures. The results showed that the most effective SPR event occurred in the AuNPs/glass binary structure produced at soliton temperature (230 K). In the next stage of the study, two different AuNPs/n-Si/Al photodetectors were produced at 300 K and 230 K substrate temperatures and the results were compared. It was determined that the photodetector produced at 230 K had a lower ideality factor, series resistance and barrier height compared to 300 K. Then, the distribution of photocurrent values of the photodetectors according to wavelength was examined and it was determined that the photocurrent value of the sample produced at 230 K was sensitive in a wider wavelength range compared to the sample produced at 300 K. Considering the experimental findings obtained, it was understood that the use of the cryogenic coating method in the production of new generation plasmonic optoelectronic devices with high performance and broadband sensitivity would be advantageous compared to other methods.