Design Criteria for Transparent Single-Wall Carbon Nanotube Thin-Film Transistors

• Published in: Nano letters 2006-04, Vol.6 (4), p.677-682
• Main Authors: Unalan, Husnu Emrah, Fanchini, Giovanni, Kanwal, Alokik, Du Pasquier, Aurelien, Chhowalla, Manish
• Format: Article
• Language: English
• Subjects: Computer Simulation; Computer-Aided Design; Cross-disciplinary physics: materials science; rheology; Crystallization - methods; Electric Conductivity; Electrochemistry - instrumentation; Electrochemistry - methods; Equipment Design; Equipment Failure Analysis; Exact sciences and technology; Materials science; Materials Testing; Models, Chemical; Nanoscale materials and structures: fabrication and characterization; Nanotechnology - instrumentation; Nanotechnology - methods; Nanotubes; Nanotubes, Carbon - chemistry; Nanotubes, Carbon - ultrastructure; Other topics in nanoscale materials and structures; Particle Size; Physics; Transistors, Electronic
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl052406l

A study based on two-dimensional percolation theory yielding quantitative parameters for optimum connectivity of transparent single-wall carbon nanotube (SWNT) thin films is reported. Optimum SWNT concentration in the filtrated solution was found to be 0.1 mg/L with a volume of 30 mL. Such parameters lead to SWNT fractions in the films of approximately Φ = 1.8 × 10-3, much below the metallic percolation threshold, which is found to be ∼ΦC = 5.5 × 10-3. Therefore, the performance of transparent carbon nanotube thin-film transistors is limited by the metallic SWNTs, even below their percolation threshold. We show how this effect is related to hopping or tunneling between neighboring metallic tubes.