High-Resolution ac Measurements of the Hall Effect in Organic Field-Effect Transistors

Chen, Y.1,3; Yi, H. T.1; Podzorov, V.1,2

2016-03-17

10.1103/PhysRevApplied.5.034008

Physical Review Applied   影响因子和分区

2331-7019

We describe a high resolving power technique for Hall-effect measurements, efficient in determining Hall mobility and carrier density in organic field-effect transistors and other low-mobility systems. We utilize a small low-frequency ac magnetic field (B-rms < 0.25 T) and a phase-sensitive (lock-in) detection of Hall voltage, with the necessary corrections for Faraday induction. This method significantly enhances the signal-to-noise ratio and eliminates the necessity of using high magnetic fields in Hall-effect studies. With the help of this method, we are able to obtain the Hall mobility and carrier density in organic transistors with a mobility as low as mu similar to 0.3 cm(2) V-1 s(-1) by using a compact desktop apparatus and low magnetic fields. We find a good agreement between Hall-effect and electric-field-effect measurements, indicating that, contrary to the common belief, certain organic semiconductors with mobilities below 1 cm(2) V-1 s(-1) can still exhibit a fully developed, band-semiconductor-like Hall effect, with the Hall mobility and carrier density matching those obtained in longitudinal transistor measurements. This suggests that, even when mu < 1 cm(2) V-1 s(-1), charges in organic semiconductors can still behave as delocalized coherent carriers. This technique paves the way to ubiquitous Hall-effect studies in a wide range of low-mobility materials and devices, where it is typically very difficult to resolve the Hall effect even in very high dc magnetic fields.

SCI ; EI

英语

其他

National Science Foundation[DMR-1506609]

Physics

Physics, Applied

WOS:000372433700001

AMER PHYSICAL SOC

20191306692773

Carrier concentration ; Electric field effects ; Hall effect devices ; Hall mobility ; Signal to noise ratio ; Transistors

Electricity: Basic Concepts and Phenomena:701.1 ; Semiconductor Devices and Integrated Circuits:714.2 ; Information Theory and Signal Processing:716.1 ; Electronic Structure of Solids:933.3

Web of Science

1.Rutgers State Univ, Dept Phys, Piscataway, NJ 08854 USA
2.Rutgers State Univ, IAMDN, Piscataway, NJ 08854 USA
3.South Univ Sci & Technol China, Dept Phys, Shenzhen 518055, Guangdong, Peoples R China

Chen, Y.,Yi, H. T.,Podzorov, V.. High-Resolution ac Measurements of the Hall Effect in Organic Field-Effect Transistors[J]. Physical Review Applied,2016,5(3).

Chen, Y.,Yi, H. T.,&Podzorov, V..(2016).High-Resolution ac Measurements of the Hall Effect in Organic Field-Effect Transistors.Physical Review Applied,5(3).

Chen, Y.,et al."High-Resolution ac Measurements of the Hall Effect in Organic Field-Effect Transistors".Physical Review Applied 5.3(2016).