Double-Gate Compensation Transistor Layout for OLED Flicker Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic light emitting diode displays face flickering issues during low-frequency display due to leakage in compensation transistors, which are affected by surrounding signals.
Innovation Solution
A display substrate design with a double-gate transistor structure for compensation transistors, where the first compensation gate pattern partially or completely overlaps the compensation channel portion, and a shielding pattern is used to stabilize voltage and shield the transistors from external signals, along with a top-and-bottom gate structure for reset transistors to prevent leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single-gate transistor structure is used for compensation transistors, then the device complexity is reduced, but the transistor leakage increases causing flickering during low-frequency display
Solution Approach 1:
The compensation transistor is divided into two gates: a first compensation gate pattern (bottom gate) and a second compensation gate pattern (top gate). This segmentation allows independent control of the channel from both sides, effectively reducing leakage current while maintaining manageable device complexity through modular gate structures.
Solution Approach 2:
The patent introduces a vertical dimension by stacking the first compensation gate pattern below the compensation active layer and the second compensation gate pattern above it. This three-dimensional double-gate configuration provides enhanced control over the compensation channel, reducing leakage without significantly increasing planar device footprint.
2Device complexity
If no shielding pattern is used, then the device complexity is reduced, but the compensation transistor is affected by surrounding signals causing leakage
Solution Approach 1:
A shielding pattern is introduced as an intermediary element between the compensation transistor and surrounding signal sources. This shielding structure acts as a barrier that blocks or filters interfering signals from adjacent circuits, protecting the compensation transistor from noise while maintaining reasonable device complexity.
3Manufacturing precision
If the first compensation gate pattern does not overlap the compensation channel portion, then the manufacturing precision is reduced, but the shielding effect is insufficient
Solution Approach 1:
The first compensation gate pattern is positioned in the vertical dimension below the compensation active layer, creating an overlapping configuration when viewed in plan. This vertical stacking provides effective shielding of the compensation channel from lateral signal interference while reducing the lateral alignment precision requirements compared to planar overlapping structures.
Data Source
AI summary
A display substrate includes: a base substrate, a plurality of sub-pixels arranged on the base substrate, a plurality of gate lines, and a plurality of first compensation gate patterns; the sub-pixel includes a sub-pixel driving circuit, and the sub-pixel driving circuit includes a compensation transistor; the compensation transistor includes a second compensation gate pattern, the first compensation gate pattern is located between a corresponding second compensation gate pattern and the base substrate, the first compensation gate pattern is coupled to a DC signal output terminal, and the second compensation gate pattern is coupled to a corresponding gate line; the compensation transistor includes a compensation active layer, the compensation active layer is located between the first compensation gate pattern and the second compensation gate pattern, and the compensation active layer includes a compensation channel portion.