Spin-Defect Probes for Contactless RF Current and Temperature Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for measuring local current flow and temperature in RF-IC devices require physical electrical contact, which is cumbersome, costly, and can lead to inaccurate results or device damage, and existing non-invasive methods suffer from spatial inhomogeneities and complexity.
Innovation Solution
A system using a sensing probe with spin defects in a solid-state lattice that emits fluorescent light upon excitation, allowing non-invasive measurement of local magnetic fields and temperatures by inducing RF current flow through the conductor without direct contact, utilizing RF fields generated by the conductor itself.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If wire-bonding and physical electrical contact methods are used to measure current flow in RF-IC devices, then electrical connection is established for testing, but the system becomes cumbersome and costly, and physical interference may cause inaccurate results or device damage
Solution Approach 1:
The patent replaces mechanical wire-bonding connections with optical detection methods. Specifically, it uses optical techniques (such as OBIRCH and EMMI) to detect electrical leakage currents and magnetic field sensing to measure current flow without physical contact. This substitution eliminates the need for cumbersome wire-bonding infrastructure while maintaining measurement capability, directly resolving the contradiction between measurement reliability and device complexity
Solution Approach 2:
The patent introduces intermediate detection fields (optical fields and magnetic fields) as mediators between the measurement system and the RF-IC device. Instead of direct electrical contact, the system uses these intermediate fields to probe current flow and temperature. This intermediary approach enables non-invasive measurement, avoiding device damage while maintaining measurement accuracy, thus resolving the contradiction between reliability and complexity
2Measurement precision
If scanning electron microscopy is used to achieve sub-nm spatial resolution, then high current sensitivity and sub-nm resolution are achieved, but hard electrical contact through wire bonds and connectors is required
Solution Approach 1:
The patent replaces mechanical electrical contact systems with optical and magnetic field-based detection. By using optical techniques to detect leakage currents and magnetic sensors to detect current-induced fields, the system achieves high spatial resolution without requiring complex wire-bonding or connector infrastructure. This substitution maintains measurement precision while dramatically simplifying operation
Solution Approach 2:
The patent creates optical copies or field representations of the electrical current flow. Instead of directly measuring current through physical contact, it uses optical fields to map current distribution and magnetic fields to represent current flow patterns. This copying approach enables high-resolution measurement without mechanical contact, resolving the contradiction between precision and ease of operation
3Measurement precision
If diamond nitrogen-vacancy center magnetometry is used to measure local magnetic fields with sub-100 nm resolution, then quantitative current density measurement is achieved, but an additional MW delivery antenna must be positioned within ultra-near-field regime, increasing system complexity and introducing spatial inhomogeneities
Solution Approach 1:
The patent extracts or removes the MW delivery antenna from the ultra-near-field positioning requirement. By using alternative detection methods that do not depend on precise near-field antenna positioning, the system eliminates the complex antenna positioning infrastructure. This extraction resolves the contradiction by maintaining measurement precision while removing the source of system complexity and spatial inhomogeneities
Solution Approach 2:
The patent uses magnetic fields as intermediaries to transfer information about current density to the sensor without requiring near-field microwave coupling. The magnetic field acts as a mediator that carries current density information from the RF-IC device to the sensor in a contactless manner, eliminating the need for complex MW antenna positioning and reducing system complexity while maintaining measurement precision
4Reliability
If physical electrical contact is established for testing RF-IC devices, then current flow can be measured, but the contact may cause device damage or inaccurate results due to connection defects
Solution Approach 1:
The patent replaces mechanical electrical contact with optical and magnetic field-based non-contact measurement. By using optical techniques to detect leakage currents and magnetic sensors to measure current-induced fields, the system eliminates physical contact that could cause device damage or connection defects. This substitution maintains test result accuracy while removing harmful mechanical contact effects
Solution Approach 2:
The patent converts the harmful effect of electrical contact into a beneficial non-contact measurement approach. Instead of using electrical contact that risks device damage, it uses the electromagnetic fields naturally generated by current flow as the measurement signal. This conversion transforms a potentially harmful interaction into a safe, non-invasive measurement method that maintains accuracy while eliminating device damage risk
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
Enables high-resolution, non-invasive, and reliable measurement of local magnetic fields and temperatures in RF current carrying conductors, reducing system complexity and avoiding spatial inhomogeneities, facilitating early detection of defects and improving fabrication reliability.
Implementation Method 1
The sensing probe comprises a solid-state lattice, in particular a diamond lattice, which contains one spin defect or an ensemble of spin defects, in particular nitrogen-vacancy (NV) centers, that are configured to emit fluorescent light upon irradiation with excitation light
Implementation Method 2
The RF field generated by the RF current flow in the conductive sample structure serves as the MW field required for the manipulation of the spin population of the NV center without the need of an external near-field MW antenna
Implementation Method 3
the AC magnetic field generated by the RF current flow induces an AC current flow in the electrically conductive sample structure
Implementation Method 4
The energy states of said spin defects is tunable by external magnetic and/or electric fields
Data Source
Figure 1~2
Figure 3A~3B
Figure 4
AI summary
The invention concerns a system and a method for non-invasive measurement of a local AC magnetic field and/or a local temperature in an electrically conductive sample structure (300). The system comprises a sensing probe (1) formed of a solid-state lattice with one or more spin defects which are tunable by external magnetic and/or electric fields, an RF transmitting antenna (2) configured to emit RF waves, and a microscope configured to determine and/or control the distance between a sensing surface (15) of the sensing probe and a surface of the electrically conductive sample (300). The RF transmitting antenna (2) is arranged at a distance (DRFT) from the surface of the conductive sample structure (300) for contactless induction of electrical RF current flow in the electrically conductive sample structure (300). The RF transmitting antenna (2) is further arranged at a distance (DRFT) from the one or more spin defects such that near-field inductive coupling between the RF transmitting antenna (2) and the one or more spin defects is prevented or substantially prevented.