p-n Junction Switch Layout for Passive Charge Carrier Storage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing monitoring devices face challenges in withstanding extreme environmental changes, such as high temperatures, and accurately recording and storing data without manual errors or power dependency, especially in environments where conventional sensors become unpredictable.
Innovation Solution
A switch device with a p-n junction and conduction layer geometry that generates an electric field opposing charge carrier migration, allowing data storage without power and enabling robust, passive recording of environmental conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If charge carriers are allowed to migrate freely in the conduction layer, then the device can operate, but data cannot be stored without power and measurements are not persistent
Solution Approach 1:
The p-doped and n-doped layers are positioned asymmetrically with a vertical offset, creating an uneven electric field distribution that selectively opposes charge carrier migration in one direction. This asymmetric geometry enables data storage functionality while maintaining device operation.
Solution Approach 2:
The invention introduces a vertical offset dimension between the p-doped and n-doped layers, moving from a planar to a three-dimensional configuration. This dimensional change creates the offset region that generates the opposing electric field, enabling persistent data storage without requiring additional power.
2Reliability
If the p-doped and n-doped layers are aligned in the same plane, then the device structure is simple, but no opposing electric field is generated to confine charge carriers
Solution Approach 1:
The p-doped and n-doped layers are positioned asymmetrically with a vertical offset, creating an uneven electric field distribution that selectively opposes charge carrier migration in one direction. This asymmetric geometry enables data storage functionality while maintaining device operation.
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 device provides reliable, tamper-resistant, and accurate data storage of environmental exposure history, independent of power sources, by confining charge carriers until a threshold voltage is reached, facilitating precise detection and storage of environmental conditions.
Implementation Method 1
an electric field generated by the p-n junction opposes the migration of the charge carriers from the first region to the second region
Data Source
Figure 1
Figure 2
Figure 3A~3C
AI summary
There is provided a switch device, comprising a substrate; a p-n junction comprising a first p-doped layer provided on the substrate and a first n-doped layer provided on the substrate and opposing the first p-doped layer; a conduction layer provided on the substrate and extending from a first region adjacent the p-doped layer to a second region adjacent the n-doped layer, wherein the conduction layer comprises a plurality of charge carriers moveable within the conduction layer and wherein, in an initial state, the concentration of charge carriers in the first region is higher than in the second region; and wherein the first p-doped layer is vertically offset relative to the first n-doped layer to provide an offset region adjacent the first p-doped layer in which a plane parallel to the surface of the substrate extends through the offset region and the first n-doped layer; and wherein a part of the conduction layer defining at least a part of the first region is provided in the offset region such that an electric field generated by the p-n junction opposes the migration of the charge carriers from the first region to the second region.