Vertical Hall Element Electrode Depth for Magnetic Sensitivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vertical Hall elements have limited magnetic sensitivity due to restricted current flow in the direction parallel to the substrate, and they face difficulties in offset voltage cancellation using the spinning current technique due to the configuration of drive and Hall voltage output electrodes.
Innovation Solution
A semiconductor device with a vertical Hall element featuring electrode sets aligned in specific directions, where the drive current supply electrodes have a greater depth than the Hall voltage output electrodes and electrode isolation diffusion layers, allowing wider current flow and enabling effective offset cancellation through the spinning current technique.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the drive current supply electrode configuration with trenches and insulating films is used to make current flow parallel to the substrate, then the current component perpendicular to the substrate is eliminated, but the width of current flow in the depth direction becomes small and sensitivity is only slightly improved
Solution Approach 1:
The patent transitions from a two-dimensional surface-level electrode configuration to a three-dimensional structure by extending the drive current supply electrode deeply into the semiconductor substrate. This vertical extension into the depth dimension allows the current to flow through a much larger volume of the substrate, significantly increasing the effective width of the current flow path in the depth direction while maintaining the parallel flow direction, thereby substantially improving magnetic sensitivity.
2Ease of operation
If the drive current supply electrode consists of conductor embedded in trench via insulating film, then current flows parallel to substrate surface, but offset cancellation by spinning current technique becomes difficult due to insulating film blocking current flow
Solution Approach 1:
The patent removes the insulating film from the drive current supply electrode configuration, extracting the problematic element that blocked current flow. By eliminating the insulating film between the drive current supply electrode and the substrate, the electrode can directly supply current to the substrate, enabling the spinning current technique to effectively cancel offset voltages while maintaining the simplified electrode structure.
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 enhances magnetic sensitivity and facilitates efficient offset voltage cancellation, resulting in a highly sensitive and accurate magnetic sensor.
Implementation Method 1
A Hall element is capable of detecting position or angle without contact as a magnetic sensor... a vertical Hall element configured to detect magnetic field components parallel to a substrate surface (horizontal magnetic field)
Data Source
Figure 1A~1C
Figure 2A~2B
Figure 3A~3B
AI summary
The vertical Hall element includes: a semiconductor layer of a second conductivity type formed on a semiconductor substrate of a first conductivity type; a first electrode set formed in a surface of the semiconductor layer and including a first drive current supply electrode, a Hall voltage output electrode, and a second drive current supply electrode aligned along a straight line extending in a first direction in this order; and second to fifth electrode sets each having the same configuration as the configuration of the first electrode set and aligned with the first electrode set along a straight line extending in a second direction perpendicular to the first direction. The Hall voltage output electrode has a first depth, the first and second drive current supply electrodes have a second depth that is larger than the first depth.