Flexible Semiconductor Device Via Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of flexible semiconductor devices faces challenges due to the need for high-temperature processes, which are restricted by the low heat resistance of resin substrates, leading to potential decreases in TFT performance and complications in machining inorganic oxide gate insulating films, especially for large-sized screens.
Innovation Solution
A flexible semiconductor device is manufactured using a metal foil with an insulating layer, a semiconductor layer, source and drain electrodes, and a flexible film layer, where vias extending through the thickness serve as alignment markers to facilitate accurate positioning of the gate electrode and improve manufacturing efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high-temperature processes are used to manufacture TFT elements, then TFT performance is improved, but resin substrates cannot withstand the heat
Solution Approach 1:
The substrate system is segmented into a heat-resistant glass substrate for TFT manufacturing and a flexible resin substrate for final application. The TFT elements are formed on the glass substrate at high temperatures, then transferred to the resin substrate, allowing each component to operate in its optimal temperature range.
Solution Approach 2:
A transfer substrate (glass substrate) acts as an intermediary that temporarily holds the TFT elements during high-temperature manufacturing. This intermediary enables the resin substrate to avoid direct exposure to high temperatures while still receiving the benefits of high-performance TFTs.
2Temperature
If glass substrates are used for TFT elements, then heat resistance is improved, but flexibility and weight are worsened
Solution Approach 1:
The substrate functionality is segmented: the glass substrate provides heat resistance during manufacturing, while the resin substrate provides flexibility and light weight for the final product. This segmentation allows both requirements to be satisfied by different components in the system.
Solution Approach 2:
The glass substrate is discarded after serving its purpose as a manufacturing platform. The TFT elements are transferred to the resin substrate, leaving the glass substrate to be removed. This allows the temporary use of heat-resistant material without the penalty of its weight and lack of flexibility in the final product.
3Weight of moving object
If transference process is used to move TFT elements to resin substrate, then flexibility is improved, but process complexity increases
Solution Approach 1:
The transfer substrate serves multiple functions: it acts as a support during TFT formation, a heating platform for high-temperature processing, and a temporary carrier during transfer to the resin substrate. By merging these functions into one component, the overall process complexity is reduced.
Solution Approach 2:
The TFT elements are pre-formed on the glass substrate with all high-temperature processing completed before transfer. This preliminary action on the heat-resistant substrate eliminates the need for complex in-situ transfer processes during high-temperature manufacturing, simplifying the overall process.
Data Source
AI summary
There is provided a method for manufacturing a flexible semiconductor device. The method of the flexible semiconductor device according to the present invention comprises the steps of: (i) forming an insulating layer on one of principal surfaces of a metal foil; (ii) forming a semiconductor layer on the insulating layer, and then forming source and drain electrodes so that the source and drain electrodes contact with the semiconductor layer; (iii) forming a flexible film layer so that the flexible film layer covers the semiconductor layer and the source and drain electrodes; (iv) forming vias in the flexible film layer, and thereby a semiconductor device precursor is provided; and (v) subjecting the metal foil to a processing treatment, and thereby forming a gate electrode from the metal foil, wherein, in the step (v) of the processing treatment of the metal foil, the gate electrode is formed in a predetermined position by using at least one of the vias of the semiconductor device precursor as an alignment marker.