Display Passivation Layer Hydrogen Control for Transistor Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices face challenges in maintaining the characteristics of transistor elements due to hydrogen incorporation in the passivation layer, which affects the reliability and performance of the transistors.
Innovation Solution
The use of silicon nitride (SiNx) with a specific ratio of silicon-hydrogen bonds (Si—H) to nitrogen-hydrogen bonds (N—H) in the range of 1:0.6 to 1:1.5 in the passivation layer, combined with a heat-treatment process to discharge excess hydrogen, minimizes the impact on transistor elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a passivation layer is formed to protect transistor elements, then reliability is improved, but hydrogen incorporation in the passivation layer causes changes in transistor characteristics
Solution Approach 1:
The patent controls the hydrogen content in the passivation layer by adjusting deposition parameters (such as silane flow rate ratio, pressure, and temperature) to achieve a specific ratio of Si-H to N-H bonds (1:0.6 to 1:1.5). This parameter optimization reduces hydrogen-induced transistor characteristic changes while maintaining passivation effectiveness
Solution Approach 2:
The patent performs preliminary heat treatment (annealing) on the passivation layer at temperatures between 200-450°C before transistor operation. This preliminary action discharges excess hydrogen from the passivation layer, preventing subsequent transistor characteristic drift and ensuring long-term stability
2Object-generated harmful factors
If the passivation layer contains hydrogen bonds for protection, then protective function is improved, but transistor element characteristics change over time
Solution Approach 1:
The patent converts the harmful effect of hydrogen (which causes transistor characteristic changes) into a beneficial outcome by controlling hydrogen release through heat treatment. The controlled discharge of hydrogen during annealing prevents long-term transistor degradation, transforming the potential harm into a protective mechanism
Solution Approach 2:
The patent optimizes the Si-H to N-H bond ratio (1:0.6 to 1:1.5) through controlled deposition parameters, achieving a balance where the passivation layer provides adequate protection while minimizing hydrogen-induced transistor characteristic changes
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
This approach stabilizes the characteristics of the transistors by reducing hydrogen content, enhancing the reliability and performance of the display device by preventing changes in transistor elements.
Implementation Method 1
combined with a heat-treatment process to discharge excess hydrogen
Data Source
AI summary
A display device includes a first conductive layer including a first voltage line and a second voltage line, a buffer layer, a semiconductor layer including a first active layer and a second active layer, a first gate insulating layer, a second conductive layer including a first gate electrode overlapping the first active layer and a second gate electrode overlapping the second active layer, a passivation layer, a via layer, a bank pattern layer including a first bank pattern and a second bank pattern partially spaced apart from each other, a third conductive layer including a first electrode and a second electrode spaced apart from each other, and light emitting elements. The passivation layer includes silicon nitride (SiNx), and a ratio of a number of silicon-hydrogen bonds (Si—H) to a number of nitrogen-hydrogen bonds (N—H) in the silicon nitride (SiNx) is in a range of about 1:0.6 to about 1:1.5.