Title :
The Effect of Dielectric Capping on Few-Layer Phosphorene Transistors: Tuning the Schottky Barrier Heights
Author :
Han Liu ; Neal, A.T. ; Mengwei Si ; Yuchen Du ; Ye, Peide D.
Author_Institution :
Birck Nanotechnol. Center, Purdue Univ., West-Lafayette, IN, USA
Abstract :
Phosphorene is a unique single elemental semiconductor with two-dimensional layered structures. In this letter, we study the transistor behavior on mechanically exfoliated few-layer phosphorene with the top-gate. We achieve a high ON-current of 144 mA/mm and hole mobility of 95.6 cm2/V·s. We deposit Al2O3 by atomic layer deposition (ALD) and study the effects of dielectric capping. We observe that the polarity of the transistors alternated from p-type to ambipolar with Al2O3 grown on the top. We attribute this transition to the changes for the effective Schottky barrier heights for both electrons and holes at the metal contact edges, which is originated from fixed charges in the ALD dielectric.
Keywords :
Schottky barriers; atomic layer deposition; elemental semiconductors; hole mobility; transistors; 2D layered structures; ALD dielectric; Al2O3; Schottky barrier heights; atomic layer deposition; dielectric capping; few-layer phosphorene transistors; hole mobility; mechanically exfoliated few-layer phosphorene; metal contact edges; p-type-ambipolar; single elemental semiconductor; Aluminum oxide; Charge carrier processes; Dielectrics; Logic gates; Schottky barriers; Transistors; Phosphorene; Schottky barrier heights; atomic layer deposition; atomic layer deposition.; field-effect transistors;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2014.2323951
