Vertical Hall Effect Element P-well Sensitivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Hall Effect elements, such as planar and vertical Hall Effect elements, have limitations in sensitivity, particularly in their orientation relative to the substrate, which affects their ability to accurately sense magnetic fields with high signal-to-noise ratio.
Innovation Solution
A vertical Hall Effect element is designed with an N-type epitaxial layer over a substrate, featuring a plurality of pickups with N+ type diffusion and a low-voltage P-well region implanted and diffused into the epitaxial layer, optimizing the Hall voltage response to magnetic fields parallel to the substrate for enhanced sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional Hall Effect elements are used, then they can sense magnetic fields, but their sensitivity is limited due to fixed orientation relative to the substrate
Solution Approach 1:
The invention transitions from conventional planar Hall Effect elements with sensitivity axes perpendicular to the substrate to a vertical Hall Effect element where the sensitive axis is parallel to the substrate. This dimensional reorientation is achieved by configuring the current flow and magnetic field interaction vertically through the epitaxial layer, enabling the sensitive axis to lie in the plane of the substrate rather than perpendicular to it.
2Adaptability or versatility
If vertical Hall Effect elements are used, then the sensitive axis is parallel to the substrate, but the sensitivity is lower compared to planar elements with perpendicular sensitivity
Solution Approach 1:
The invention introduces a vertically-oriented pinned magnet positioned beneath specific regions of the vertical Hall Effect element. This localized magnetic field source creates enhanced magnetic flux concentration in specific areas of the epitaxial layer, thereby locally amplifying the magnetic field interaction and improving the overall sensitivity and signal-to-noise ratio of the device.
Solution Approach 2:
The invention combines multiple functional layers and components including the N-type epitaxial layer, P-type substrate, pinned magnet, and separation regions into a composite vertical Hall Effect element structure. This composite architecture integrates the advantages of vertical orientation with enhanced sensitivity mechanisms, achieving both adaptability to in-plane magnetic fields and improved measurement precision.
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 configuration results in a Hall Effect element with improved sensitivity, capable of generating a Hall voltage responsive to magnetic fields, achieving a sensitivity of about five to six microvolts per Gauss per volt, effectively addressing the limitations of existing Hall Effect elements.
Implementation Method 1
The Hall element is configured to generate a Hall voltage between at least one pair of the plurality of pickups. The Hall voltage is most responsive to a magnetic field directed parallel to a major surface of the substrate.
Data Source
AI summary
A vertical Hall Effect element includes a low voltage P-well region disposed at a position between pickups of a vertical Hall Effect element to result in an improved sensitivity of the vertical Hall Effect element. A method results in the vertical Hall Effect element having the improved sensitivity.