On the transconductance of polysilicon thin film transistors

In order to achieve both driver and display capability for a number of display devices, TFT has attracted attention, model calculations are therefore presented for the grain boundary barrier height, in a polysilicon TFT considering the charge neutrality between the intrinsic free carriers and the grain boundary trap states. The formation of the potential barrier at a grain boundary is considered due to the trapping of carriers at the localized grain boundary trap states. The trapped charges, influenced by the gate bias voltage and the trapping states density, in turn, have been taken to deplete free carriers near the grain boundary in a device such as polysilicon TFT. The present predictions reveal that the barrier height diversely depends on the gate source voltage (VGS) of a TFT along with other crystal parameter. Finally to obtain the transconductance, the contributions of transverse and longitudinal grain boundary resistances are incorporated in the I-V characteristics of a TFT. For all values of grain size, the transconductance of the device is seen to increase initially with the gate voltage (VGS) which finally appears to be saturated. The dependence of the transconductance on grain size and drain voltage has been thoroughly explored. Good agreement with experimental results is achieved. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2299

Activation energy of polycrystalline silicon thin film transistor

The activation energy of a poly-Si thin film transistor is observed to be influenced by the grain size, trap state density and the inversion layer thickness. The present study aims to investigate these parameters theoretically so as to explore optimum conditions for the working of a polycrystalline silicon thin film transistor. Our computations have revealed that the activation energy decreases with the increase of gate bias for all values of grain size, trap states density and the inversion layer thickness. These findings are compared with the experimental results. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2201

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Not AvailableBlood and hair samples were collected from seventy adult cattle reared in villages located near the industrial effluent contaminated River adjoining Meerut. Based on the distance of the villages from the river, they were divided into three areas viz. area 1 (villages located on the river bank), area 2 (villages within 1km distance from the river) and area 3 (villages more than 2 km from the river). Samples collected from cattle reared in rural locality away from the river were used as control. The mean lead (Pb) and cadmium (Cd) levels of blood and hair in the animals of area 1 and area 2 were significantly higher (P<0.05) as compared to control animals. The mean Pb and Cd levels of animals of area 3 were not significantly different from control values. Significantly low (P<0.05) copper and iron concentration in blood and hair were recorded in the animals from area1 and area 2 as compared to area 3 and control animals. Blood and hair zinc levels were not significantly different among animals of different areas. The blood cadmium level had significant negative correlation with blood copper(r=-0.379, p<0.01) and iron(r= -0.395, p<0.01). The blood lead levels had significant negative correlation with blood iron (r= -0.138, p< 0.05) and hair copper (r= -0.178, p< 0.05) and iron (r= -0.302, p< 0.05). The blood cadmium level had significant negative correlation with hair copper (r=-0.377, p< 0.01) and iron (r= -0.482, p<0.01). The study concludes that blood lead and cadmium influenced the concentration of trace minerals in the blood and hair.ICA