Crystalline Organic Semiconductor Device for Efficient Charge Transport
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The development of bipolar transistors based on organic semiconductor materials is hindered by the amorphous structure of most organic materials, which results in inefficient charge carrier transport and short diffusion lengths, making it difficult to achieve the necessary long-range order for effective pn junction formation and device performance.
Innovation Solution
A controlled organic semiconductor device is created using crystalline organic semiconductor layers with different conductivity types, achieved through flash crystallization and epitaxial growth, allowing for efficient charge carrier transport and extended diffusion lengths, thereby enhancing the performance of bipolar transistors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If amorphous organic semiconductor materials are used, then the material can be easily processed and deposited, but the charge carrier transport efficiency is low and diffusion length is short
Solution Approach 1:
The patent changes the structural parameter of organic semiconductor materials from amorphous to crystalline form. This parameter change fundamentally improves charge carrier transport efficiency and diffusion length while maintaining processability through controlled crystallization methods
Solution Approach 2:
The patent uses composite material structures combining organic semiconductor crystals with appropriate substrates and encapsulation layers. This composite approach enables the crystalline material to be processed and integrated into functional devices while maintaining its superior charge transport properties
2Reliability
If conventional sublimation methods are used to grow organic crystals, then high quality crystals with good order can be obtained, but the process is costly and slow
Solution Approach 1:
The patent changes the processing parameters from conventional slow sublimation to rapid crystallization methods. By controlling temperature gradients, deposition rates, and substrate conditions, high-quality crystals are obtained much faster, significantly improving manufacturing productivity
Solution Approach 2:
The patent employs preliminary substrate preparation and nucleation control before crystal growth. This preliminary action ensures that crystals grow with correct orientation and high quality from the start, eliminating the need for slow iterative growth processes
3Reliability
If thick organic crystal layers are used, then long diffusion lengths can be achieved, but the base length of the transistor must be at least one crystal thickness
Solution Approach 1:
The patent changes the parameter of crystal thickness to optimized thin film dimensions. By achieving high crystallinity in thin layers through controlled deposition, the diffusion length is sufficient for device operation while the base length can be minimized for better device performance and integration
4Adaptability or versatility
If organic semiconductor devices are used, then flexibility, transparency, and low weight are achieved, but device complexity increases compared to inorganic devices
Solution Approach 1:
The patent segments the organic semiconductor device into distinct functional layers (substrate, semiconductor layer, electrodes, encapsulation). This segmentation allows each layer to be optimized independently and simplifies the overall device structure and manufacturing process
Solution Approach 2:
The patent designs the organic semiconductor device structure to serve multiple functions: the crystalline semiconductor layer provides both mechanical flexibility and electrical functionality, while the substrate serves as both structural support and potential active component. This multi-functionality reduces overall device complexity
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
The use of crystalline organic semiconductor layers enables improved regulation, higher switching frequency, and increased power handling at high frequencies, along with flexibility, transparency, low weight, and reduced material consumption, compared to inorganic semiconductor devices.
Implementation Method 1
The use of crystalline organic semiconductor layers enables, for example, effective charge carrier transport
Implementation Method 2
the diffusion length of charge carriers to recombination correlates with the degree of order in the system
Implementation Method 3
achieved through flash crystallization and epitaxial growth
Data Source
AI summary
In various embodiments, there is provided a controlled organic semiconductor device comprising a crystalline first organic semiconductor layer on or over a substrate, the crystalline first organic semiconductor layer having a first conductivity type; and a crystalline second organic semiconductor layer on or over the first organic semiconductor layer, the crystalline second organic semiconductor layer having a second conductivity type, the first conductivity type being different from the second conductivity type.