Akademik Veri Yönetim Sistemi
Erzincan Üniversitesi Fen Bilimleri Enstitüsü Dergisi, cilt.14, sa.2, ss.524-541, 2021 (Hakemli Dergi)
Graphene is thought to be an outstanding material for novel photoelectrical devices due to its unique properties.
However, because of the atomic thickness of the interaction lenght between graphene and light, the performance
of graphene-based photoelectrical devices is limited. Therefore, in this presented study, graphene derivatives
such as graphene oxide (GO) and reduced graphene oxide (rGO) were used instead of graphene to enhance the
light absorption for metal-interlayer-semiconductor type Schottky heterojunction fabrication. Firstly, GO
synthesis was made by the modified Hummer method, then rGO synthesis was carried out via the chemical
reduction method by using L-ascorbic acid (LAA) as a reducing agent. The surface morphology, chemical
compositions and optical properties of the synthesized materials were characterized using SEM-EDS, and UVVis-NIR spectrophotometer analyses. Subsequently, GO/n-Si and rGO/n-Si heterojunction device fabrications
were made by using the spin coating method. The main junction parameters of the fabricated devices were
determined using current-voltage (I-V) measurements. The obtained results indicate that the rGO thin film layer
has a significant impact on the I-V characteristics due to its improved characteristics compared to the GO thin
film. For this reason, I-V measurements of the rGO/n-Si heterojunction device were have been investigated as
a function of temperature. The results revealed that the ideality factor (n), and series resistance (Rs) increased
by the decreasing temperature while the barrier height (Φb) decreases. Furthermore, I-V measurements of the
rGO/n-Si heterojunction device were performed under light illumination at room temperature. The obtained
results showed that the synthesized rGO material can be used in optoelectronic applications such as photodiodes
and photodetectors.