Display Panel Light-Shielding Layout for Fewer LTPO Masks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices using LTPO technology face complex manufacturing processes due to the large number of masks required, leading to high costs and issues with photosensitivity and electrical properties of oxide thin-film transistors due to the absence of bottom gates.
Innovation Solution
A display panel design incorporating a light shielding layer with a grid structure that shields active portions of transistors, reducing the number of masks by eliminating certain layers and ensuring proper gate coverage, thereby improving photosensitivity and electrical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If LTPO technology is applied to reduce power consumption and increase screen-to-body ratio, then power consumption is reduced, but the number of masks increases making the manufacturing process complex and costly
Solution Approach 1:
The patent merges the light shielding function with the gate electrode structure by forming the gate electrode directly over the active layer without requiring a separate light shielding layer. This integration eliminates multiple manufacturing steps and masks while maintaining both the low-power LTPO functionality and the necessary light shielding properties.
Solution Approach 2:
The gate electrode structure is designed to serve multiple functions simultaneously: it acts as both the control electrode for the transistor and the light shielding layer. This multi-functional design reduces the total number of layers and masks required in the manufacturing process while preserving the power consumption benefits of LTPO technology.
2Device complexity
If gate layers and insulating layers are removed to reduce the number of masks, then manufacturing complexity is reduced, but photosensitivity and electrical properties of oxide thin-film transistors deteriorate
Solution Approach 1:
The patent performs preliminary doping of the active layer to achieve the desired electrical properties before forming the gate electrode. This preliminary action ensures that the transistor maintains good electrical characteristics and photosensitivity even with the simplified layer structure, eliminating the need for additional insulating layers that would otherwise be required.
Solution Approach 2:
The patent changes the doping parameters of the active layer to compensate for the reduced layer structure. By adjusting the doping concentration and distribution, the transistor maintains its electrical properties and photosensitivity without requiring the full complement of gate layers and insulating layers, thus reducing mask count while preserving reliability.
3Ease of manufacture
If bottom gates of oxide thin-film transistors are absent, then manufacturing steps are reduced, but photosensitivity and electrical properties deteriorate
Solution Approach 1:
The patent transitions from a planar bottom-gate structure to a vertical top-gate structure. This dimensional change allows the gate electrode to be positioned directly over the active layer, providing effective light shielding and electrical control without requiring the complex multi-layer bottom gate structure. The vertical arrangement maintains photosensitivity and electrical properties while simplifying manufacturing.
Data Source
AI summary
A display panel includes a light shielding layer, a first semiconductor layer, and a second semiconductor layer. The light shielding layer includes a first light shielding portion, a second light shielding portion and a third light shielding portion. The first light shielding portion can shield a first active portion of a drive transistor. The second light shielding portion can shield a third active portion of a compensation transistor. The third light shielding portion can shield a fourth active portion of a first initialization transistor.