Organic Electroluminescence Display Panel Top Gate Configuration
Solution Overview
Problem
Current organic electroluminescence display panels face challenges with current leakage in low temperature polysilicon thin-film transistors (LTPS-TFTs) and low electron mobility in oxide-TFTs, complicating the manufacturing process with numerous masking steps required for high-performance TFTs.
Innovation Solution
The implementation of a top gate configuration for both LTPS-TFT and Oxide-TFT, where the active layers are located below the gates, allowing for the simplification of source and drain formation using a single lithography process, reducing the complexity and number of masking processes required.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If LTPS-TFT is used in the display panel, then stability is improved, but current leakage occurs
Solution Approach 1:
The display panel is divided into a first region containing LTPS-TFTs and a second region containing Oxide-TFTs. This segmentation allows each transistor type to be optimized for its specific function: LTPS-TFTs provide stability in the first region, while Oxide-TFTs with low leakage characteristics handle current control in the second region, thereby resolving the current leakage problem while maintaining stability.
2Object-generated harmful factors
If Oxide-TFT is used in the display panel, then current leakage is reduced, but electron mobility is low
Solution Approach 1:
Different regions of the display panel are assigned different transistor types based on local functional requirements. The first region uses LTPS-TFTs where high electron mobility is needed for switching operations, while the second region uses Oxide-TFTs where low current leakage is the priority for current control in the organic electroluminescence layer, thus optimizing performance locally in each region.
3Reliability
If high-performance TFT is manufactured with multiple masking steps, then device performance is improved, but manufacturing complexity increases
Solution Approach 1:
The patent combines the formation of LTPS-TFTs and Oxide-TFTs into a unified manufacturing process flow. By integrating the fabrication steps for both transistor types and utilizing a shared planarization layer structure, the number of masking steps is reduced from the conventional eleven steps to ten steps, thereby lowering manufacturing complexity while maintaining high device performance.
Data Source
AI summary
The present disclosure discloses an organic electroluminescence display panel, a method for manufacturing the display panel, and a display apparatus. The organic electroluminescence display panel includes: a substrate including a first region and a second region adjacent to each other; a buffer layer located on the substrate; a first active layer located on the buffer layer in the first region; a first gate located on the first active layer and insulated from the first active layer; a second active layer located on the buffer layer in the second region; a metal electrode located on the first gate and insulated from the first gate; and a second gate located on the second active layer and insulated from the second active layer.