Polysilicon-Oxide TFT Structure for Fast Turn-On Speed
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices face challenges in achieving high turn-on speed and reliability for thin film transistors, which are crucial for efficient pixel control and overall display performance.
Innovation Solution
The proposed display device incorporates thin film transistors with a polysilicon semiconductor pattern and an oxide semiconductor pattern, featuring vertical crystals. The transistor structure includes specific electrode configurations and insulation layers to enhance performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional thin film transistors are used in display devices, then manufacturing process is simpler, but turn-on speed and reliability are insufficient
Solution Approach 1:
The patent employs composite material structures by combining polysilicon semiconductor patterns with oxide semiconductor patterns in the same transistor device. This composite approach leverages the high mobility carrier characteristics of polysilicon and the high off-state current blocking capability of oxide semiconductors, thereby improving both turn-on speed and reliability simultaneously.
Solution Approach 2:
The patent applies local quality by differentiating the semiconductor material properties at different locations within the transistor structure. Specifically, polysilicon is used in regions requiring high carrier mobility (for fast turn-on) while oxide semiconductor is used in regions requiring high blocking capability (for reliability and low leakage), optimizing each local region for its specific function.
2Speed
If conventional thin film transistors are used, then device structure is simpler, but turn-on speed is insufficient for efficient pixel control
Solution Approach 1:
The composite material structure combines polysilicon and oxide semiconductor to achieve fast turn-on speed through the high carrier mobility of polysilicon while maintaining reliability through oxide semiconductor's blocking capability, resolving the speed-reliability trade-off.
Solution Approach 2:
The patent changes the material parameter of the semiconductor layer from conventional single-material to composite material, fundamentally altering the transistor's electrical characteristics to achieve both high speed and high reliability performance.
Data Source
AI summary
A display device includes a base substrate, a first transistor, a second transistor, an organic light emitting diode, and a capacitor electrically connected to the first thin film transistor. The first transistor includes a first semiconductor pattern below a first interlayer insulation layer and a first control electrode above the first interlayer insulation layer and below a second interlayer insulation layer. The second transistor includes a second control electrode above the first interlayer insulation layer and below the second interlayer insulation layer. A second semiconductor pattern is above the second interlayer insulation layer.