Storage Capacitor Aperture Ratio via Dielectric Thickness Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In active matrix liquid crystal displays, the design of a storage capacitor is limited by the need to balance aperture ratio and light transmittance, as larger capacitors reduce light transmission while smaller capacitors compromise capacitance and coupling effects.
Innovation Solution
A method involving a photoresist layer coated on a dielectric layer, exposed using a mask pattern to reduce the thickness of the dielectric layer and electrode area, allowing for a storage capacitor with increased aperture ratio while maintaining sufficient capacitance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the storage capacitor is designed in a larger scale, then the capacitance and potential-holding capability are improved, but the aperture ratio and light transmittance are reduced
Solution Approach 1:
The patent transitions from controlling capacitance through area (2D) to controlling capacitance through thickness (1D). By making the dielectric layer thickness the primary control parameter instead of electrode area, the invention enables capacitance adjustment without affecting the aperture ratio, thus resolving the contradiction between capacitance and light transmittance.
Solution Approach 2:
The invention changes the critical parameter from electrode area to dielectric layer thickness. By controlling the thickness of the dielectric layer (particularly the second dielectric layer) to be less than that of the metal layer, the patent achieves the desired capacitance while minimizing the electrode area, thereby maintaining high aperture ratio and light transmittance.
2Illumination intensity
If the electrode area is reduced to increase aperture ratio, then light transmittance is improved, but the capacitance and coupling effects are reduced
Solution Approach 1:
The patent shifts the control dimension from area (2D) to thickness (1D). By adjusting the dielectric layer thickness rather than electrode area, the invention achieves capacitance control without compromising aperture ratio, effectively resolving this contradiction.
Solution Approach 2:
The invention changes the controlling parameter from electrode area to dielectric layer thickness. Specifically, by making the second dielectric layer thinner than the metal layer, the patent achieves sufficient capacitance with reduced electrode area, thereby maintaining high aperture ratio while preserving coupling effects.
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 method effectively reduces the electrode area of the storage capacitor, enhancing the aperture ratio of liquid crystal display pixels while preserving capacitance, thereby addressing the trade-off between capacitance and light transmittance.
Implementation Method 1
a photoresist layer is coated on a dielectric layer and exposed to light by making use of patterns on a mask, then a developing process and an etching process are carried out in sequence to reduce the thickness of the dielectric layer
Data Source
AI summary
Disclosed is a method of manufacturing a storage capacitor having increased aperture ratio: providing a substrate having a metal layer disposed thereon, and said metal layer is covered correspondingly with a first dielectric layer and a second dielectric layer in sequence; forming a photoresist layer with a uniform thickness to cover said second dielectric layer; performing a process of exposure-to-light and development to a portion of said photoresist layer that is correspondingly disposed over said metal layer sequentially, so that its thickness is less than its original thickness; removing said photoresist layer and etching said portion of said second dielectric layer, so that a thickness of said portion of said second dielectric layer is less than its original thickness, and the etching depth of said portion is greater than that of the other remaining portions of said second dielectric layer; and forming an electrode layer on said second dielectric layer.