Carbon Nanotube Bolometer Alignment via Interlayer Capillary Action
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Carbon nanotube-based infrared sensors face limitations due to low Temperature Coefficient of Resistance (TCR) and high resistance, primarily because of the presence of metallic carbon nanotubes and difficulties in removing ionic surfactants used for semiconducting carbon nanotube separation.
Innovation Solution
A method involving the formation of an interlayer on a substrate to enhance carbon nanotube alignment, using a material like APTES or polylysine, which allows a semiconducting carbon nanotube dispersion liquid to move and align in a predetermined direction, resulting in a highly aligned carbon nanotube layer with improved TCR and reduced resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If metallic carbon nanotubes are present in the carbon nanotube thin film, then the film can be formed easily, but the TCR value becomes low and sensor performance is limited
Solution Approach 1:
The patent applies ionic surfactant treatment to extract and remove metallic carbon nanotubes from the mixed carbon nanotube film, leaving behind semiconducting carbon nanotubes with high TCR values. This extraction process resolves the contradiction by eliminating the harmful metallic component while preserving the ease of film formation achieved through the surfactant-assisted deposition method.
Solution Approach 2:
The patent changes the chemical composition parameter of the carbon nanotube film by controlling the ratio of metallic to semiconducting carbon nanotubes through selective removal. By adjusting the ionic surfactant concentration and treatment conditions, the film composition is modified to achieve high TCR values while maintaining manufacturability.
2Measurement precision
If ionic surfactant is used to separate semiconducting carbon nanotubes, then TCR value improves, but the surfactant cannot be easily removed and resistance becomes high
Solution Approach 1:
The patent employs a multi-step purification process where the ionic surfactant is systematically removed through washing and treatment steps. The surfactant is discarded through controlled removal procedures, and the carbon nanotube film is recovered with high TCR values and low resistance, resolving the contradiction between surfactant necessity and removal difficulty.
Solution Approach 2:
The patent introduces an intermediary washing or treatment step that facilitates the removal of the ionic surfactant. This intermediary process acts as a bridge between the surfactant-based separation and the final clean film, enabling easy surfactant removal while preserving the high TCR value achieved through initial separation.
3Ease of manufacture
If carbon nanotubes are not aligned in a predetermined direction, then the manufacturing process is simple, but the TCR value and sensitivity are reduced
Solution Approach 1:
The patent applies a preliminary action by using ionic surfactant treatment during the deposition process to induce alignment of carbon nanotubes in a predetermined direction. This preliminary alignment action simplifies subsequent manufacturing steps while achieving high TCR values and sensitivity, resolving the contradiction between process simplicity and performance.
Solution Approach 2:
The patent changes the spatial arrangement parameter of carbon nanotubes from random orientation to aligned orientation in a predetermined direction. This parameter change is achieved through controlled deposition conditions and ionic surfactant treatment, resulting in improved TCR values and sensitivity while maintaining manufacturing simplicity.
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 enables the creation of a bolometer with a high TCR value and low resistance, enhancing sensitivity and noise reduction, while also allowing for downsizing and increased productivity.
Implementation Method 1
fabricating an interlayer having a function that enhances binding between a substrate and a carbon nanotube
Implementation Method 2
making a semiconducting carbon nanotube dispersion liquid move on the interlayer in one direction relative to the fabricated interlayer
Data Source
AI summary
An object of the present invention is to provide a bolometer having a high TCR value and a low resistance, and a method for manufacturing the same.According to the present invention, a bolometer manufacturing method including: fabricating an interlayer having a function that enhances binding between a substrate and a carbon nanotube, in a predetermined shape on the substrate; and, making a semiconducting carbon nanotube dispersion liquid move on the interlayer in one direction relative to the fabricated interlayer is provided.