High Voltage Graphene Nanowall Trench MOS Barrier Schottky Diode Characterization for High Temperature Applications

• Main Authors: Rahimah Mohd Saman, Sharaifah Kamariah Wan Sabli, Mohd Rofei Mat Hussin, Muhammad Hilmi Othman, Muhammad Aniq Shazni Mohammad Haniff, Mohd Ismahadi Syono
• Format: Article
• Language: English
• Published: MDPI AG 2019-04-01
• Series: Applied Sciences
• Subjects: graphene nanowall; carbon nanowall; trench Schottky diode; leakage current; Schottky barrier
• Online Access: https://www.mdpi.com/2076-3417/9/8/1587

Graphene&#8217;s superior electronic and thermal properties have gained extensive attention from research and industrial sectors to study and develop the material for various applications such as in sensors and diodes. In this paper, the characteristics and performance of carbon-based nanostructure applied on a Trench Metal Oxide Semiconductor MOS barrier Schottky (TMBS) diode were investigated for high temperature application. The structure used for this study was silicon substrate with a trench and filled trench with gate oxide and polysilicon gate. A graphene nanowall (GNW) or carbon nanowall (CNW), as a barrier layer, was grown using the plasma enhanced chemical vapor deposition (PECVD) method. The TMBS device was then tested to determine the leakage current at 60 V under various temperature settings and compared against a conventional metal-based TMBS device using TiSi₂ as a Schottky barrier layer. Current-voltage (I-V) measurement data were analyzed to obtain the Schottky barrier height, ideality factor, and series resistance (R_s) values. From I-V measurement, leakage current measured at 60 V and at 423 K of the GNW-TMBS and TiSi₂-TMBS diodes were 0.0685 mA and above 10 mA, respectively, indicating that the GNW-TMBS diode has high operating temperature advantages. The Schottky barrier height, ideality factor, and series resistance based on <i>dV/dln(J)</i> vs. <i>J</i> for the GNW were calculated to be 0.703 eV, 1.64, and 35 ohm respectively.