X-ray detector top electrode area control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Direct-type digital X-ray detectors experience image quality degradation due to varying leakage current in p-intrinsic-n (PIN) diodes, which is influenced by the slope shape of the side-walls, leading to non-uniform screen images.
Innovation Solution
The X-ray detector design includes a photodetecting portion with a top electrode smaller than the semiconductor area, which helps maintain a constant leakage current by controlling the electric field and reducing leakage current variations through the PIN diode.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the top electrode area is made equal to or larger than the semiconductor area, then the manufacturing process is simpler, but the leakage current becomes non-uniform and image quality degrades
Solution Approach 1:
The top electrode is designed with a specific area relationship (smaller than the semiconductor area) to create a localized electric field distribution that ensures uniform leakage current characteristics in the critical detection region, thereby improving image quality while maintaining manufacturing feasibility
2Adaptability or versatility
If the side-wall slope of the PIN diode is varied, then the device can be manufactured with different geometries, but the leakage current characteristics become non-uniform and screen images become non-uniform
Solution Approach 1:
The patent controls the side-wall slope parameter of the PIN diode within a specific range to maintain uniform electric field distribution and consistent leakage current characteristics across the detector, ensuring uniform screen images while allowing for manufacturing variations
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 design ensures uniform leakage current, improving image quality by minimizing the impact of side-wall slope variations on the PIN diode, resulting in consistent and high-quality image output.
Implementation Method 1
a pixel electrode of the TFT can detect an amount of current corresponding to a degree of charges that the Se layer receives
Implementation Method 2
an electric field can vary significantly, depending on the slope shape of the side-walls of the PIN diode
Data Source
AI summary
An X-ray detector device includes in one example a switching portion and a photodetecting portion connected to the switching portion. The photodetecting portion includes a bottom electrode, a semiconductor area disposed above the bottom electrode, and a top electrode disposed above the semiconductor area. The area of the top electrode is smaller than the area of a top surface of the semiconductor area.