Charge Sensing Device Tuning Quantum Capacitance via Gate Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electronic devices with 2-dimensional charge sensing layers face limitations in sensitivity and dynamic range due to the series effect of quantum capacitance, and often fail to operate around the most sensitive Fermi level, specifically the charge neutrality point, which restricts their performance in high sensitivity and dynamic range applications.
Innovation Solution
An electronic apparatus with a gate electrode structure, dielectric structure, and a 2-dimensional charge sensing layer that allows for active control of quantum capacitance by applying a selected gate voltage to operate around the charge neutrality point, thereby tuning sensitivity and dynamic range, using a control unit to adjust the gate voltage for different operating modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the device operates away from the charge neutrality point, then the quantum capacitance is naturally higher providing larger dynamic range, but the sensitivity is reduced and the device does not operate at the most sensitive point
Solution Approach 1:
The patent implements dynamic control of the gate voltage to adjust the operating point of the device. By making the gate voltage可调 (adjustable), the system can dynamically shift between operating near the charge neutrality point for high sensitivity measurements and moving away from it for larger dynamic range applications, thus resolving the contradiction between sensitivity and adaptability
Solution Approach 2:
The patent changes the electrical parameter (gate voltage) to control the Fermi level position relative to the charge neutrality point. By adjusting this parameter, the quantum capacitance can be tuned to optimize either sensitivity (when operating near CNP) or dynamic range (when operating farther from CNP), allowing the system to adapt to different measurement requirements
2Measurement precision
If the gate voltage is adjusted to operate around the charge neutrality point, then the sensitivity is maximized, but the quantum capacitance decreases reducing the dynamic range
Solution Approach 1:
The system employs dynamic gate voltage control to adjust the operating point. When high sensitivity is required, the gate voltage is set to operate near the charge neutrality point where quantum capacitance is minimized. When larger dynamic range is needed, the gate voltage can be adjusted to move away from the CNP, thereby increasing quantum capacitance. This dynamic adjustment resolves the contradiction between sensitivity and quantum capacitance quantity
3Measurement precision
If the dielectric thickness is increased to minimize capacitance and maximize output voltage, then the sensitivity is improved, but the device complexity and parasitic capacitance management become more challenging
Solution Approach 1:
Instead of relying solely on increasing dielectric thickness to minimize capacitance, the patent changes the operational parameter (gate voltage) to control the quantum capacitance contribution. By adjusting the gate voltage to operate near the charge neutrality point, the quantum capacitance is minimized, which effectively reduces the total capacitance and maximizes output voltage sensitivity without requiring thicker dielectrics or more complex device structures
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 the electronic device to achieve high sensitivity and dynamic range applications by actively controlling the quantum capacitance, enhancing the output voltage and expanding the device's operational capabilities beyond the limitations of traditional systems.
Implementation Method 1
said charge sensing structure shows a quantum capacitance in series with said gate capacitance resulting in a total capacitance between the charge sensing structure and the gate electrode structure
Implementation Method 2
a gate electrode structure; a dielectric structure arranged over said gate electrode structure
Data Source
AI summary
The present invention relates to a system comprising an electronic apparatus which comprises: —an electronic device comprising: —a gate electrode (G, BE); —a dielectric (D) arranged over the gate electrode (G, BE); and —a charge sensing structure (CE) with a 2-dimensional charge sensing layer to provide a gate capacitance (Cg) between the charge sensing structure (CE) and the gate electrode structure (G, BE) and a quantum capacitance (Cq) resulting in a total capacitance (Ctot); —a voltage detector to detect an output voltage (Vo) stored in the total capacitance (Ctot). The system further comprises means to apply a gate voltage (Vg) to the gate electrode structure (G, BE) selected to: —make the device operate around most sensitive point of fermi level of the charge sensing structure (CE); and —tune the quantum capacitance (Cq). The present invention also relates to an electronic apparatus adapted to allow the tuning of its quantum capacitance.