Effect of Channel Length Variation on the Electrical Conductivity of Passivated Back-Gated Graphene Field-Effect Transistor (GFET) Using Silvaco TCAD Tools

Hazim Guzali; Nur Idayu Ayob; Aliza Aini Md Ralib; Mohamad Adzhar Md Zawawi; Cik Rohaida Che Hak; Zuraida Ahmad

doi:10.4028/p-b57hzW

Paper Titles

Microstructure on Inner Surface of Cell Walls inside Aluminum Alloy Foam Fabricated via Semi-Solid Route
p.15

Study on Film Morphology of Liquid Droplet Evaporation in Confined Space
p.27

Voltage-Induced Director Orientations in IPS-Liquid Crystal Cells with Different Electrode Structures
p.33

Optical Absorption and Bandgap Modulation in Diamond-Like Carbon Films for Anti-Reflection
p.39

Effect of Channel Length Variation on the Electrical Conductivity of Passivated Back-Gated Graphene Field-Effect Transistor (GFET) Using Silvaco TCAD Tools
p.47

The Heat Dissipation Effect of Liquid Cooling Heat Sink Based on Triply Periodic Minimal Surface Structure
p.57

Study on the Properties of Water Bamboo Shoot Shell as Bio-Based Flame Retardant and its Epoxy Composite Application
p.67

Thermal and Rheological Properties of Hemp Fiber/Polybutylene Succinate (PBS) Composites
p.73

Additive Manufacturing of HDPE Composites Reinforced with Alkali-Treated Saccharum Munja Fibers: Processing, Characterization, and Properties
p.81

HomeKey Engineering MaterialsKey Engineering Materials Vol. 1059Effect of Channel Length Variation on the...

Effect of Channel Length Variation on the Electrical Conductivity of Passivated Back-Gated Graphene Field-Effect Transistor (GFET) Using Silvaco TCAD Tools

Abstract:

This paper presents the simulation study of passivated backgated graphene field-effect transistors (GFETs) with different channel lengths using Victory Device tool by Silvaco TCAD. The passivated backgated GFETs were designed for radiation device applications. Six GFETs models with channel lengths ranging from 0.1 µm to 10 µm were analyzed to investigate the influence of variation in channel length on the conductivity of GFET. Nearly all devices with shorter channel lengths exhibit ambipolar characteristics with V-shaped curves, indicating the conductivity of holes and electrons at different bias conditions. Interestingly, GFETs with longer channels, specifically 3 µm, 5 µm, and 10 µm, exhibited unexpected W-shaped transfer characteristic curves, featuring multiple charge neutrality points (CNPs). This behavior is attributed to the non-uniform doping induced by charge interactions between the channel and the passivation layer. The central region of the channel may experience a higher doping effect due to impurity diffusion from the passivation material compared to the region near to the metal electrodes. However, the W-shaped curves of longer channel GFETs become less prominent when compared to smaller channel length devices. This suggests that high conductivity in shorter channel GFETs dominates the overall transfer curve performance. The analysis of output characteristics (I_D–V_D) at V_G = 10 V further supports the influence of channel length on device performance, with the shortest channel length (0.1 µm) recording the highest saturation current (I_SAT), followed closely by 0.6 µm, aligning with its strong ambipolar transfer characteristics. These findings highlight the importance of channel scaling in designing stable and reliable backgated GFETs for radiation applications.