Organic Thin Film Transistor Auxiliary Structures for Single Crystal Growth
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thin film transistors with organic semiconductors face challenges in charge mobility due to polycrystalline growth and precise pattern formation, which can damage the semiconductor during lithography processes.
Innovation Solution
A method involving the formation of auxiliary structures on a substrate with an organic semiconductor deposited between them using thermal evaporation at controlled temperatures and deposition rates, allowing for continuous single crystal-like active layer growth without damaging the semiconductor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If lithography process is used to form organic semiconductor pattern, then pattern precision is improved, but the organic semiconductor is damaged by chemical solution
Solution Approach 1:
The patent extracts and removes the harmful lithography process entirely from the manufacturing sequence. Instead of depositing organic semiconductor over the entire substrate and then using lithography to remove unwanted material, the invention forms the organic semiconductor pattern directly through selective deposition only in the desired channel region between source and drain electrodes, eliminating chemical solution exposure completely
Solution Approach 2:
The patent segments the deposition process into selective regions using a shadow mask, allowing organic semiconductor to be deposited only in the channel formation region between source and drain electrodes while preventing deposition in other areas. This spatial segmentation eliminates the need for subsequent lithography patterning steps
2Ease of manufacture
If shadow mask is used during deposition, then pattern formation is simplified, but the pattern precision deteriorates
Solution Approach 1:
The patent changes the deposition parameters by using an extremely low deposition rate (0.005-0.05 Å/s) and controlled substrate temperature (85-100°C), which enables the shadow mask to produce high-precision patterns. The slow deposition rate allows for better control of material distribution and sharper pattern edges, overcoming the typical precision limitations of shadow mask methods
3Productivity
If organic semiconductor is deposited at high deposition rate, then productivity is improved, but charge mobility deteriorates due to polycrystal formation
Solution Approach 1:
The patent changes the deposition rate parameter to an extremely low range (0.005-0.05 Å/s) and maintains controlled substrate temperature (85-100°C) during deposition. These parameter changes enable the organic semiconductor to grow as single crystal or single crystal-like structures with high charge mobility, while the overall productivity is maintained through optimized process design and reduced reliance on multiple patterning 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 enhances charge mobility in thin film transistors without damaging the organic semiconductor, improving pattern precision and process complexity while maintaining semiconductor integrity.
Implementation Method 1
The forming the active layer may include thermally evaporating an organic semiconductor to form the active layer continuously grown between the pair of auxiliary structures
Implementation Method 2
a low molecular organic semiconductor among the organic semiconductors may be mainly formed through deposition such as thermal evaporation
Implementation Method 3
The organic semiconductor may be formed into a desired (and/or alternatively predetermined) pattern by using a shadow mask during deposition or performing a lithography process after deposited on the whole surface of a substrate
Implementation Method 4
performing the thermally evaporating of the organic semiconductor at a substrate temperature of greater than or equal to about 85° C. and a deposition rate of less than about 0.1 Å/s
Data Source
AI summary
A thin film transistor includes a pair of auxiliary structures facing each other on a substrate, an active layer including an organic semiconductor and continuously grown between the pair of auxiliary structures, a gate electrode on the substrate and overlapped by the active layer, and a source electrode and a drain electrode electrically connected to the active layer. A method of manufacturing the thin film transistor is disclosed.