High Field Effects

Chen, C.-Y. Kanicki, J. 1996. High field-effect-mobility a-Si H TFT based on high deposition rate PECVD materials. IEEE Electron Device Lett. 17 437-439. 

This equation gives the final expression for trapped holes in the presence of high field effects,... 

The above discussion demonstrates that high field effects included in the FDTO model modify the OFET characteristics very significantly. The FDTO model is in very good agreement with the experimental results. The model has been compared with two sets of experiments [158], The experimental data for -6T [157] is compared with the FDTO... 

One example of inorganic (particulate) materials is zinc oxide (ZnO). ZnO is a non-toxic and transparent material and a good n-type semiconductor. Charge carrier mobilities obtained in FETs exceed the amorphous silicon benchmark of 1 cm A s [24, 25]. However, to obtain these high field-effect mobilities, the ZnO films have to be annealed at temperatures incompatible with flexible substrates. 

In field-effect transistors based on the thin films of poly(3-alkyl)thiophene derivatives, high field-effect mobility has been observed because of the formation of crystal-like grains [116]. The mobility depends strongly upon the crystallinity of the thin films. Introduction of liquid crystallinity into conjugated polymers is expected to be effective for enhancing microscopic crystallization of conjugated polymers to increase their carrier mobilities. It can also cause anisotropy in various physical properties if macroscopic molecular alignment is achieved. 

The remainder of this chapter is organised as follows. First, we briefly describe a typical system which has been used to achieve intense fields, the purpose being to stress the experimental connection between high laser fields and short pulses. We move on to describe various high field effects, together with simple physical explanations which have been used to interpret them. We then return to our main discussion about the role of atomic physics in these effects and, finally, to the description of a theoretical picture which holds promise to describe the response of many-electron atoms in strong fields. 

Angelis, F.D. et al.. High field-effect mobility pentacene thin-film transistors with polymethylmethacrylate buffer layer, Appl. Phys. Lett. 86, 203505, 2005. 

Meng, H. et al.. High field-effect mobihty oligofluorene derivatives with high envi-romnental stabihty, J. Am. Chem. Soc. 123, 9214—9215, 2001. 

Hong, X.M. et al., Thiophene-phenylene and thiophene-thiazole oligomeric semiconductors with high field-effect transistor on/off ratios, Chem. Mater. 13,4686-4691,2001. 

Chikamatsu, M. et al.. Solution-processed n-type organic thin-film transistors with high field-effect mobility, App. Phys. Lett. 87, 203504, 2005. 

H. Meng, Z. Bao, A. J. Lovinger, B. C. Wang, and A. M. Mujsce. High Field-Effect Mobility Oligofluorene Derivatives with High Environmental Stability. Journal of the American Chemical Society, 123(37) 9214-9215, 2001. 

P. Pingel, A. Zen, D. Neher, I. Lieberwirth, G. Wegner, S. Allard, and U. Scherf, Unexpectedly high field-effect mobility of a soluble, low molecular weight ohgoquaterthiophene fraction with low polydispersity. Appl. Phys. A Mater. Sci. Process., 95, 67 (2009). 

CLUSTERING OF GAS MOLECULES ON IONS AND THE STANDARD HIGH-FIELD EFFECT... 

Non-Blanc phenomena for mobility and diffusion occur for all ions in any gas mixture and thus may be viewed as standard high-field effects (2.1). Now we transition to nonstandard effects that involve inelasticity of collisions or alignment of polyatomic ions. 

As discussed in 2.2.1, the standard high-field effect ensues from cross sections O depending on the ion-molecule colhsion velocities that increase at greater E/N. 

---