TFT Array Substrate Light-Shielding Layer Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing TFT-LCD fabricating process lacks full shielding of the TFT structure, leading to increased leakage current due to light exposure, which affects the stability of the thin-film-transistor (TFT) devices.
Innovation Solution
A TFT array substrate is designed with a light-shielding layer that overlaps specific regions of the active layer, connected to the gate electrode through via holes, to block light and prevent leakage current, enhancing the stability of the TFT array substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the TFT structure is not fully shielded in the existing fabricating process, then the manufacturing process is simpler, but light exposure causes electron transition and increases leakage current, affecting TFT stability
Solution Approach 1:
The light-shielding layer is segmented into two distinct parts: a first light-shielding layer covering the second region (lightly-doped region) and a second light-shielding layer covering the first region (non-doped region). This segmentation allows each layer to be optimized for its specific function and positioned at different heights, effectively blocking light exposure to critical regions while maintaining manufacturing feasibility
Solution Approach 2:
The shielding solution extends into the vertical dimension by creating light-shielding layers at different heights. The first light-shielding layer is positioned at a first height covering the lightly-doped region, while the second light-shielding layer is positioned at a second height covering the non-doped region. This multi-level shielding approach effectively blocks light exposure paths without requiring excessive lateral expansion, thus managing complexity through vertical stratification
2Object-affected harmful factors
If a light-shielding layer is added to block light exposure, then leakage current is reduced and TFT stability is improved, but the device structure becomes more complex
Solution Approach 1:
Different regions of the TFT structure receive differentiated shielding treatments. The first light-shielding layer is specifically positioned to cover the second region (lightly-doped region) at a first height, while the second light-shielding layer covers the first region (non-doped region) at a second height. This localized shielding approach targets light exposure effects at their source without unnecessarily complicating the entire device structure
Solution Approach 2:
The light-shielding layers act as intermediary elements between the light source and the sensitive TFT regions. By introducing these intermediate shielding structures, light exposure is blocked before it can cause electron transition and leakage current, effectively mediating the harmful interaction between light and the TFT structure
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The light-shielding layer effectively reduces leakage current and enhances the stability of the TFT array substrate by blocking light exposure, particularly in lightly-doped regions, thereby improving the overall performance of the TFT devices.
Implementation Method 1
a first light-shielding layer that overlaps with the first region and substantially covers the second region... The light-shielding layer effectively reduces leakage current and enhances the stability of the TFT array substrate by blocking light exposure
Data Source
AI summary
In accordance with some embodiments of the disclosed subject of matter, a TFT array substrate, a method for fabricating the TFT array substrate, and a display panel that comprises the TFT array substrate are provided. In some embodiments, the TFT array substrate comprises: a substrate; an active layer comprising a first region, a source region, a drain region, and a second region between the drain region and the first region; a gate electrode above the first insulating layer, wherein the gate electrode substantially covers the first region; and a first light-shielding layer that overlaps with the first region and substantially covers the second region.