Thin Film Transistor Patterning for Source-Drain Coverage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thin film transistor manufacturing processes face issues with over-etching during the one-time patterning of the protective electrode and source-drain layers, leading to incomplete coverage and oxidation of the source-drain layer, which affects conductivity and performance.
Innovation Solution
A method involving simultaneous patterning of semiconductor and conductive thin films to form the active and protective electrode layers, with a photoresist pattern that ensures proper insulation and coverage, followed by dry etching to disconnect the protective electrodes and surface treatment to adjust oxygen vacancies, thereby improving the coverage and conductivity of the source-drain layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a one-time patterning process is used to form the protective electrode layer and source-drain layer simultaneously, then the manufacturing process is simplified, but over-etching occurs leading to incomplete coverage and oxidation of the source-drain layer
Solution Approach 1:
The patent divides the patterning process into two separate stages: first forming the protective electrode layer with initial coverage, then performing a second patterning process to form the source-drain layer with precise coverage. This segmentation allows each layer to be optimized independently, preventing over-etching while maintaining manufacturing efficiency.
Solution Approach 2:
The protective electrode layer is formed first as a preliminary layer that provides initial coverage and protection. This preliminary action ensures that the source-drain layer is protected during subsequent processing steps, preventing oxidation and incomplete coverage issues.
2Reliability
If the protective electrode layer is formed to completely cover the source-drain layer, then oxidation and metal ion diffusion are prevented, but the manufacturing complexity increases
Solution Approach 1:
The patent combines the protective electrode layer and source-drain layer formation into an integrated two-stage patterning process. The protective electrode layer serves dual purposes: as a protective barrier and as part of the final device structure, reducing the need for additional separate processing steps.
Solution Approach 2:
The patent optimizes etching parameters and photoresist thickness to achieve complete coverage of the source-drain layer by the protective electrode layer. By carefully controlling etching depth and photoresist dimensions, the process achieves reliable protection without requiring excessive additional steps.
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 the probability of over-etching and oxidation, enhancing the conductivity and performance of the thin film transistor by ensuring complete coverage of the source-drain layer and preventing metal ion diffusion.
Implementation Method 1
forming a photoresist layer on the conductive thin film, and performing exposure and development on the photoresist layer to acquire a photoresist pattern
Implementation Method 2
performing wet etching on the semiconductor thin film and the conductive thin film simultaneously to remove a portion, corresponding to the photoresist completely-removed region, of the semiconductor thin film and a portion, corresponding to the photoresist completely-removed region, of the conductive thin film
Implementation Method 3
removing the photoresist in the second photoresist region and removing a portion, corresponding to the second photoresist region, of the protective electrode layer by dry etching
Data Source
AI summary
A method for manufacturing a thin film transistor is provided. The method includes: sequentially forming a semiconductor thin film, a patterned source-drain layer and a conductive thin film on a base substrate, performing a patterning process on the semiconductor thin film and the conductive thin film simultaneously to acquire an active layer and a protective electrode layer, and processing the protective electrode layer such that a portion of the protective electrode layer covering the source is insulated from a portion of the protective electrode layer covering the drain.