• Hovarth, J.
• Mejia, I.
• Salas-Villasenor, A. L.
• Gnade, B. E.
• Ramirez-Bon, R.
• Cha, D. K.
• Quevedo-Lopez, M. A.

Abstract

Cadmium sulfide thin film transistors were demonstrated as the n-type device for use in flexible electronics. CdS thin films were deposited by chemical bath deposition (70° C) on either 100 nm HfO2 or SiO2 as the gate dielectrics. Common gate transistors with channel lengths of 40-100 μm were fabricated with source and drain aluminum top contacts defined using a shadow mask process. No thermal annealing was performed throughout the device process. X-ray diffraction results clearly show the hexagonal crystalline phase of CdS. The electrical performance of HfO 2 /CdS -based thin film transistors shows a field effect mobility and threshold voltage of 25 cm2 V-1 s-1 and 2 V, respectively. Improvement in carrier mobility is associated with better nucleation and growth of CdS films deposited on HfO2. © 2010 The Electrochemical Society.

Topics

• Deposition
• impedance spectroscopy
• mobility
• x-ray diffraction
• thin film
• crystalline phase
• aluminium
• annealing
• Cadmium