Polycrystalline silicon thin film transistor and preparation method thereof, display panel and display device

• Main Authors: CAI QIZHE, WANG CUIYU
• Format: Patent
• Language: Chinese; English
• Published: 29.10.2021
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

The invention discloses a preparation method of a polycrystalline silicon thin film transistor. The preparation method comprises the following steps: selecting a substrate; preparing a grid electrode on the substrate; preparing a gate insulating layer on the gate and the substrate; preparing a multi-layer structure on the gate insulating layer, wherein the multi-layer structure comprises a first active layer, a first amorphous Si doped layer, a second amorphous Si doped layer, a source electrode and a drain electrode; preparing a protection layer with a via hole on the polycrystalline silicon section, the source electrode and the drain electrode; and preparing a transparent conductive layer on the protective layer, wherein the transparent conductive layer is communicated with the drain electrode through a via hole. The preparation method of the polycrystalline silicon thin film transistor is not limited by the length of a laser beam of excimer laser annealing, and can be applied to a large substrate; a multi-