LCD Pixel Electrodes Stacked Layer Structure Chuck Stain Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional LCD device fabrication processes face challenges in forming pixel and common electrodes with widths less than 4.3 μm due to 'chuck stain' defects, which limit light transmittance and prevent the formation of fine line-width electrodes necessary for higher definition displays.
Innovation Solution
A method involving a stacked layer structure of a transparent conductive material layer and an opaque metal layer, with a line-width of 3.5 μm or less, is used to form pixel and common electrodes, preventing chuck stain by controlling transmittance and allowing for finer line-widths and increased light transmittance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a single transparent conductive material layer is used to form electrodes, then light transmittance is maximized, but chuck stain defects occur during photolithography process
Solution Approach 1:
The patent uses a composite electrode structure consisting of a transparent conductive material layer (such as ITO) and an opaque metal layer (such as Mo, Ti, or Al). This composite structure allows control of light transmittance while preventing chuck stain defects. The transparent conductive material layer provides high transmittance, while the opaque metal layer, when patterned with appropriate line-width, reduces overall transmittance to prevent chuck stain during photolithography.
Solution Approach 2:
The patent changes the transmittance parameter of the electrode by controlling the line-width of the opaque metal layer. When the line-width is 3.5 μm or less, the electrode transmittance is reduced to 70% or less, which prevents chuck stain defects during photolithography while maintaining sufficient light transmittance for display performance.
2Manufacturing precision
If electrode line-width is reduced to increase definition, then higher definition display is achieved, but chuck stain defects prevent formation of fine line-width electrodes
Solution Approach 1:
The composite structure of transparent conductive material layer and opaque metal layer enables formation of fine line-width electrodes (3.5 μm or less) without chuck stain defects. The opaque metal layer's patterned structure provides the necessary transmittance control that allows photolithography to proceed successfully with fine line-width features.
Solution Approach 2:
By controlling the opaque metal layer line-width to be 3.5 μm or less, the patent achieves both fine electrode features for high definition display and sufficient transmittance reduction to prevent chuck stain, thereby simultaneously achieving manufacturing precision and reliability.
3Illumination intensity
If electrode transmittance is increased to improve display brightness, then light transmittance is enhanced, but chuck stain defects occur during fabrication
Solution Approach 1:
The patent uses a composite structure where the transparent conductive material layer provides high transmittance capability while the opaque metal layer, when patterned with line-width of 3.5 μm or less, provides transmittance reduction to prevent chuck stain. This composite approach allows optimization of both display brightness and fabrication processability.
Solution Approach 2:
The patent optimizes the electrode transmittance parameter by controlling the opaque metal layer line-width to be 3.5 μm or less, achieving a balance where transmittance is sufficient for display performance (70% or less) while preventing chuck stain defects during photolithography fabrication process.
Data Source
AI summary
A liquid crystal display device is disclosed. The liquid crystal display device includes: a substrate; gate and data lines arranged to cross each other on the substrate and to define a pixel region; a switching element disposed at an intersection of the gate and data lines; and pixel electrodes and common electrodes arranged alternately with each other and parallel to the data line, within the pixel region. The pixel electrode and the common electrode are formed to have a stacked layer structure of a transparent conductive material layer and an opaque metal layer, each having a line-width of 3.5 μm or less. Such a liquid crystal display device can enhance the transmittance of a pixel region with preventing the chuck stain by forming electrodes in a double layer structure with a transparent conductive material layer and an opaque metal layer.