MIM Capacitor Terminal Electrode Positioning to Eliminate Substrate Capacitance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Metal-insulator-metal (MIM) capacitors experience substrate capacitance issues due to terminal electrode placement, leading to fluctuations in capacitance and potential malfunction of electronic circuits, especially when operated at multiple frequencies.
Innovation Solution
The capacitor design includes a substrate, a lower electrode, a dielectric film, an upper electrode, and terminal electrodes where the upper electrode and first terminal electrode are positioned within the region of the lower electrode, preventing capacitive coupling across the substrate, thus eliminating substrate capacitance and maintaining stable charge storage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the terminal electrode extends beyond the lower electrode region, then electrical connection is improved, but substrate capacitance is generated causing capacitance fluctuation
Solution Approach 1:
The harmful portion of the terminal electrode that extends beyond the lower electrode region is extracted or removed. The terminal electrode is designed to be positioned within the lower electrode region, preventing it from extending outward and creating substrate capacitance. This extraction of the problematic geometry eliminates the parasitic capacitance path while maintaining the essential electrical connection function.
Solution Approach 2:
The terminal electrode is positioned with specific local geometric constraints - it is confined to the region where the lower electrode exists. This local positioning strategy ensures that the terminal electrode makes proper electrical contact where needed while avoiding extension into regions that would create capacitive coupling with the substrate. The local quality of the electrode placement is optimized to prevent harmful effects.
2Adaptability or versatility
If the capacitor is operated at multiple frequencies, then versatility is improved, but substrate capacitance fluctuation causes malfunction
Solution Approach 1:
The substrate capacitance problem that limits frequency adaptability is extracted or eliminated by proper terminal electrode positioning. By confining the terminal electrode within the lower electrode region, the parasitic capacitance path is removed, enabling the capacitor to operate reliably across multiple frequencies without the destabilizing effect of substrate capacitance fluctuation.
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
This design effectively prevents substrate capacitance fluctuations, ensuring reliable charge storage and frequency characteristics, thereby preventing electronic circuit malfunctions.
Implementation Method 1
a capacitor having a parallel plate type structure in which an insulator is sandwiched between a lower electrode and an upper electrode
Implementation Method 2
a dielectric film disposed on the lower electrode
Data Source
AI summary
A capacitor that prevents generation of a substrate capacitance composed of an upper electrode, a substrate, and a lower electrode. Specifically, the capacitor includes a substrate; a lower electrode disposed on the substrate; a dielectric film disposed on the lower electrode; an upper electrode disposed on a part of the dielectric film; and a first terminal electrode that is connected to the upper electrode. Moreover, the upper electrode and the first terminal electrode are formed in a region for forming the lower electrode in a plan view of the capacitor viewed from the first terminal electrode side.