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A highly Sensitive Temperature Sensor based on Au/graphene-PVP/n-Si type Schottky Diodes and the Possible Conduction Mechanisms in the wide range temperatures      
Yazarlar
Doç. Dr. Osman ÇİÇEK Doç. Dr. Osman ÇİÇEK
Kastamonu Üniversitesi, Türkiye
Şemsettin Altındal
Gazi Üniversitesi, Türkiye
Yashar Azizian Kalandaragh
Özet
We report that the sensitive temperature response and possible Conduction Mechanisms (CMs) of Au/graphene-PVP/ ${n}$ -Si type Schottky diodes (SDs) are investigated using the standard Thermionic Emission (TE) theory at low temperatures (LTs) and high temperatures (HTs). The obtained results indicate that the zero-apparent barrier height ( $\phi _{\textit {Bo}}$ - $\phi _{\textit {ap}}$ ) increases while the ideality factor ( ${n}$ ), series and shunt resistances ( ${R} _{s}$ , ${R} _{\textit {sh}}$ ), rectifying rate (at ±2V) and surface states ( ${N} _{\textit {ss}}$ ) decrease with increasing temperature. The $\phi _{\textit {Bo}}$ , ${n}$ and ${R} _{s}$ values are also extracted from Cheung's functions and, then compared with those obtained TE theory. The conventional Richardson plot ( $\ell {n}$ ( ${I} _{o}$ /T 2)-q/kT) displays the deviation from the linearity at low-temperatures ( $T\le140$ K). Besides, the experimental value of Richardson constant ( ${A} ^{\ast }$ ) deduced from the intercept of plot was found to be several orders lower than the theoretical value. The discrepancies and higher values for the parameter of ${n}$ are important evidences for the deviation from TE theory. This is mainly attributed to the spatial inhomogeneities of the barrier height and potential fluctuations at the interface including low/high barrier areas. Hence the CMs across diode preferentially flows through these lower barriers/patches at the regions of LTs. The decrement in the ${N} _{\textit {ss}}$ with the enhancement in the temperature is in relation to the molecular restructuring-reordering under temperature and voltage effects. The SDs fabricated with graphene-PVP interlayer exhibit a higher sensitivity ( ${S}$ ) rather than many silicon/SOI-based structures. Numerically, the ${S}$ values are found to be in a range of 1.3 mV/K (LTs)/-1.93mV/K (HTs) in case of ${I} =0.1\,\,\mu \text{A}$ as against much greater values of -8.2 mV/K (LTs)/-7.9mV/K (HTs) for ${I} = 10\,\,\mu \text{A}$.
Anahtar Kelimeler
Sensitive temperature response,Au/graphene-PVP/n-Si structure,the possible conduction mechanisms
Makale Türü Özgün Makale
Makale Alt Türü SSCI, AHCI, SCI, SCI-Exp dergilerinde yayımlanan tam makale
Dergi Adı IEEE Sensors Journal
Dergi ISSN 1530-437X
Dergi Tarandığı Indeksler SCI-Expanded
Dergi Grubu Q2
Makale Dili İngilizce
Basım Tarihi 12-2020
Cilt No 20
Sayı 23
Sayfalar 14081 / 14089
Doi Numarası 10.1109/JSEN.2020.3009108
Makale Linki https://ieeexplore.ieee.org/document/9141298/