Rutgers University

Charge Transport in Single-Crystal Organic Transistors

Abstract: Recently, the organic field-effect transistors (OFETs) have been fabricated on organic molecular crystals with the innovative techniques that preserve the high quality of pristine single-crystal surfaces [1,2]. The single-crystal OFETs provide a unique opportunity for realization of the intrinsic (not limited by disorder) charge transport on the surface of organic semiconductors and to explore the fundamental limits of OFET performance determined solely by the physics of polaronic transport in defect-free organic materials. The intrinsic regime is characterized with the anisotropy of carrier mobility [2] and a pronounced growth of the mobility with cooling [3]. The room-temperature mobility of p-type carriers on the rubrene surface in this regime can be as high as 20 cm²/V×s [3]. I will discuss various aspects of the transport of field-induced carriers on organic surfaces, including our recent experiments on the Hall effect [4] and different light-induced effects in OFETs [5].

The research is supported by the NSF grants DMR 0405208 and ECS 0437932.

1. V. Podzorov et al., Appl. Phys. Lett. . 82, 1739 (2003); ibid. 83, 3504 (2003).
2. V. C. Sundar et al., Science 303, 1644 (2004) .
3. V. Podzorov et al., Phys. Rev. Lett. 93, 086602 (2004).
4. V. Podzorov et al., "Hall effect in the accumulation layers on the surface of organic semiconductors",
   cond-mat/0508006.
5. V. Podzorov, V. M. Pudalov, and M. E. Gershenson, Appl. Phys. Lett. 85, 6039 (2004); V. Podzorov and M. E. Gershenson, Phys. Rev. Lett. 95, 016602 (2005).