Conductance-dependent negative differential resistance in organic memory devices

Abstract

Single-layer organic memories made of organic material with good conductance have been characterized. Asymmetrical bistable behaviors under biases of opposite polarities are observed for devices with asymmetric electrodes. It is experimentally confirmed that a close correlation exists between the conductivity of the organic layer and the asymmetric bistability of the device under opposite biases. Inserting a block layer or thickening the organic layer will result in negative differential resistance under positive biases, leading to reversible symmetrical bistability. The phenomena are ascribed to the presence of filamentary microconducting channels in the organic layer.

Studies of photosensitivity and photo-induced negative differential resistance (NDR) of TIPS-pentacene-poly(3-hexyl)thiophene blend organic thin film transistor

“…The structural and electrical anisotropy of organic materials induces anisotropic charge conduction and electrical hysteresis curves [20]. Because of the switching capability using two different resistance states and hysteresis, some of the p-conjugated polymers and small molecules were used for active layers in the memory devices [21,22]. The NDR effect and switching mechanism of the organic-based memory devices can be explained in terms of filament mechanism, charge trapping/de-trapping, and/or formation of an oxide layer on interface, etc.…”

Current-Voltage Characteristics of the Metal / Organic Semiconductor / Metal Structures: Top and Bottom Contact Configuration Case

“…Trap recharging, diffusion of mobile ions, formation and dissociation of bipolarons in the accumulation layer should be considered [20]. Considering nature of the negative resistance phenomena observed in present study for some samples it should be mentioned, that negative differential resistance effect was already reported for some organic semiconductor based structures [22][23][24][25][26]. Considering nature of the negative resistance phenomena observed in present study for some samples it should be mentioned, that negative differential resistance effect was already reported for some organic semiconductor based structures [22][23][24][25][26].…”

“…Particularly, in [21] larger I-V hysteresis in the case of the top contact sample in comparison with bottom contact ones was explained by formation of the effective potential barrier under the drain electrode due to the charging of the insulator interface. Organic semiconductor based devices with bistable I-V characteristics containing negative differential resistance region was proposed as a possible memory devices [25,26]. Organic semiconductor based devices with bistable I-V characteristics containing negative differential resistance region was proposed as a possible memory devices [25,26].…”

Negative Differential Resistance Behavior in n‐Channel Organic Thin‐Film Transistors Based on C60and PTCDI‐C8: Electrical Characterization and Parameter Extraction

“…Even though NDR must be eliminated for some organic microelectronic applications, it has significantly potential applications and must be controlled in organic switching and organic nonvolatile resistive memory devices. [54][55][56][57][58] Thus, it is essential to understand and control the origin of NDR. There are many studies on NDR in organic small-molecule-based p-channel OTFTs in the published research.…”