X-Ray Light-Receiving Element Layout for Stable Electric Fields
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
X-ray imaging elements face challenges in resisting fluctuations in capacity and electric field due to X-ray irradiation, leading to generation of fixed electric charge and interface states, which affects their performance.
Innovation Solution
A light-receiving element is designed with a semiconductor substrate having a photoelectric conversion region, multiple electrically-conductive regions, and an electrically-conductive film applied between these regions to suppress the generation of fixed electric charge and interface states during X-ray irradiation, enhancing resistance to capacity and electric field fluctuations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a simple integrated structure of photoelectric conversion region and floating diffusion region is used, then ease of manufacture is improved, but resistance to fluctuations in capacity and electric field due to X-ray irradiation deteriorates
Solution Approach 1:
The device is divided into distinct functional regions: photoelectric conversion region, floating diffusion region, and guard ring region. This segmentation isolates the sensitive photoelectric conversion and floating diffusion regions from direct X-ray exposure effects by introducing the guard ring as a protective intermediate structure, thereby improving resistance to capacity and electric field fluctuations while maintaining the integrated structure's manufacturing simplicity
Solution Approach 2:
The guard ring acts as an intermediary element between the photoelectric conversion region and the floating diffusion region. It absorbs and redistributes the electric field stress and fixed electric charge generated by X-ray irradiation, protecting the sensitive regions from direct damage and maintaining device reliability without complicating the manufacturing process
2Measurement precision
If the thickness of photoelectric conversion region is increased to improve sensitivity, then photoelectric conversion efficiency is improved, but generation of fixed electric charge and interface states under X-ray irradiation increases
Solution Approach 1:
The guard ring is designed to utilize the fixed electric charge and interface states generated by X-ray irradiation in a beneficial way. By positioning the guard ring to collect and redistribute these charges, it prevents them from accumulating in harmful concentrations within the photoelectric conversion region, thereby maintaining high sensitivity while mitigating the harmful effects of X-ray exposure
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 solution effectively reduces the generation of dark current and improves the resistance of X-ray imaging elements to capacity and electric field fluctuations, ensuring stable performance under X-ray irradiation.
Implementation Method 1
an electrically-conductive film provided above the first surface at least between the first first electrically-conductive region and the second first electrically-conductive region, wherein the electrically-conductive film applies an electric field to the interface of the first surface
Implementation Method 2
a semiconductor substrate including a photoelectric conversion region... generating signal charge based on an X-ray
Data Source
AI summary
A light-receiving element according to an embodiment of the present disclosure includes: a semiconductor substrate including a photoelectric conversion region; a first first electrically-conductive region provided at an interface of a first surface of the semiconductor substrate and coupled to a first electrode; a second first electrically-conductive region provided at the interface of the first surface and around the first first electrically-conductive region and coupled to a second electrode; a third first electrically-conductive region provided at the interface of the first surface and around the second first electrically-conductive region and being in an electrically floating state; and an electrically-conductive film provided above the first surface at least between the first first electrically-conductive region and the second first electrically-conductive region.