Low-frequency noise of directly synthesized graphene/Si(100) junction

• Published in: Diamond and related materials 2022-08, Vol.127, p.109207, Article 109207
• Main Authors: Glemža, J., Palenskis, V., Gudaitis, R., Jankauskas, Š., Guobienė, A., Vasiliauskas, A., Meškinis, Š., Pralgauskaitė, S., Matukas, J.
• Format: Article
• Language: English
• Subjects: Bias; Current voltage characteristics; Defect; Defects; Electrical junctions; Electrical noise; Fluctuations; Graphene; Graphene/Si junction; LF noise; Microwave plasmas; Plasma enhanced chemical vapor deposition; Raman spectra; Raman spectroscopy; Silicon substrates
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2022.109207

A detailed investigation of the low-frequency noise in graphene/n-Si(100) junctions at forward and reverse bias has been performed. The graphene has been synthesized directly on the Si(100) substrate by a microwave plasma-enhanced chemical vapor deposition (PECVD) without any catalyst. Relation between the current-voltage (I-V) and the noise characteristics has been found. Tunneling through the graphene/Si junction is determined to be dominant in the observed linear (ohmic) part of the I-V characteristic at low bias, where electrical noise increases as a square of flowing current through the sample. The prevailing type of defects, density of the graphene defect and number of the graphene layers have been determined using Raman spectroscopy. Comparison between the measured noise and Raman spectra has been performed to evaluate influence of properties of the graphene structure on the low-frequency noise characteristics of the graphene/n-Si(100) junctions. [Display omitted] •Graphene has been synthesized directly on the Si(100) substrate.•Linear current-voltage characteristic part at forward and reverse bias is visible.•Noise intensity decreases while defect density in graphene layer increases.