Thin-Film Transistor Hydrogen Ion Removal via Electrical Field Annealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In the manufacturing process of thin-film transistors, excess hydrogen ions can diffuse into the active layer from the gate and etch stop layers, leading to performance deterioration due to the use of silicon oxide materials deposited by PECVD, which results in hydrogen ions entering the conductive channel region.
Innovation Solution
A method involving the formation of a gate, gate insulator layer, and active layer on a base substrate, where a voltage is applied between the active layer and the gate to generate an electrical field, directing impurity ions, such as hydrogen ions, from the active layer into the gate insulator layer during annealing, thereby reducing their concentration in the active layer and improving transistor performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If silicon oxide materials are deposited by PECVD in the gate insulator layer and etch stop layer, then the manufacturing process is simplified and materials are readily available, but hydrogen ions diffuse into the active layer causing performance deterioration
Solution Approach 1:
The patent applies a preliminary annealing treatment to the gate insulator layer and etch stop layer before assembling the transistor structure. This preliminary action reduces the hydrogen ion content in these layers in advance, preventing hydrogen ion diffusion into the active layer during subsequent manufacturing processes, thereby resolving the contradiction between ease of manufacture and transistor performance
Solution Approach 2:
The patent introduces a nitrogen-containing insulating layer as an intermediary barrier between the silicon oxide-based gate insulator layer/etch stop layer and the active layer. This intermediary layer prevents hydrogen ion diffusion while allowing the manufacturing process to continue using readily available silicon oxide materials, thus maintaining ease of manufacture while improving transistor performance
2Reliability
If annealing is applied to reduce impurity ions in the active layer, then carrier mobility improves, but the process complexity increases
Solution Approach 1:
The patent combines the annealing process for reducing impurity ions with the existing manufacturing process flow by performing annealing on the gate insulator layer and etch stop layer before assembly. This merging approach achieves the benefit of reduced impurity ions and improved carrier mobility without significantly increasing overall process complexity
Solution Approach 2:
The patent performs preliminary annealing treatment on the gate insulator layer and etch stop layer to reduce hydrogen ion content before assembling the transistor structure. This preliminary action reduces the need for complex post-assembly processing, thereby improving carrier mobility while keeping the overall process complexity manageable
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 reduces structural defects and impurity ion content in the active layer, enhancing the performance of the thin-film transistor by moving hydrogen ions into the gate insulator layer, thus improving carrier mobility and reducing oxygen vacancies.
Implementation Method 1
applying a voltage between the active layer and the gate to generate an electrical field therebetween, a direction of the electrical field being configured such that the impurity ions move from the active layer into the gate insulator layer
Implementation Method 2
while implementing an annealing on the active layer
Data Source
AI summary
In an embodiment, there is provided a method of manufacturing a thin-film transistor. The method includes steps of: forming a gate, a gate insulator layer and an active layer on a base substrate, wherein, the gate and the active layer are provided at upper and lower sides of the gate insulator layer, respectively, and the active layer contains impurity ions therein; and, while implementing an annealing on the active layer, applying a voltage between the active layer and the gate to generate an electrical field therebetween, a direction of the electrical field being configured such that the impurity ions move from the active layer into the gate insulator layer. Meanwhile, there are also provided a thin-film transistor, an array substrate and a display apparatus.