Thin film transistor, manufacturing method thereof, array substrate and display device

Abstract

An embodiment of the invention provides a thin film transistor, a manufacturing method thereof, an array substrate and a display device and relates to the technical field of display. On-state current can be increased while leakage current is lowered. The thin film transistor comprises a source electrode, a drain electrode, a grid electrode and a semiconductor active layer, the semiconductor active layer comprises a first sub semiconductor layer and a second sub semiconductor layer, and the first sub semiconductor layer is close to the grid electrode; at least a portion corresponding to an area between the source electrode and the drain electrode in the first sub semiconductor layer is composed of polycrystalline silicon, and a portion corresponding to the area between the source electrode and the drain electrode in the second sub semiconductor layer at least comprises noncrystalline silicon.

Description

technical field [0001] The invention relates to the field of display technology, in particular to a thin film transistor and a preparation method thereof, an array substrate, and a display device. Background technique [0002] With the development of liquid crystal display technology, the requirements for electron mobility of the thin film transistor (Thin Film Transistor, TFT) semiconductor layer are higher, and the low temperature polysilicon thin film transistor (Low Temperature Poly-silicon Thin Film Transistor, LTPS TFT) came into being LTPS TFT has been widely used in electronic products including computers and mobile phones due to its high mobility, low temperature (below 600°C), flexible substrate selection, and low fabrication cost. In various electronic displays, including. [0003] Two important indicators for evaluating the characteristics of LTPS TFT devices are on-state current and leakage current. The larger the on-state current and the smaller the leakage cu...

AI Technical Summary

Problems solved by technology

However, in the prior art, the on-state current is increased by increasing the electron mobility between the source and the drain. In this way, when the TFT is in the off state, due to the electron mobility between the source and the drain Larger, making it difficult to form a complete PN structure on the drain side, which in turn leads to an increase in leakage current

Of course, in order to reduce the leakage current, the electron mobility between the source and drain must be reduced accordingly, resulting in a reduction in the on-state current.

Therefore, in the prior art, the on-state current of the LTPS TFT device cannot be guaranteed to be large and the leakage current is small

Images