Nanotextured Capacitor Electrodes via Oxidation-Reduction Surface Structuring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for increasing the surface area of capacitors in microelectronic devices, such as nano wires, nano tubes, and porous metal or foam, are complicated and expensive, limiting their practical application in enhancing integration density in integrated circuits.
Innovation Solution
The formation of nanotextured conductive surfaces on capacitor plates through chemical oxidation and reduction processes, creating nanograins that significantly increase the surface area of capacitors, including parallel, vertical, and three-dimensional folding capacitors, using methods like plasma ashing and forming gas annealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional methods (nano wires, nano tubes, porous metal) are used to increase capacitor surface area, then capacitance is improved, but manufacturing complexity and cost increase
Solution Approach 1:
The patent changes the surface morphology parameter of the capacitor electrode by forming nanotextured surfaces through controlled oxidation and reduction processes. This transforms a flat surface into a nanoscale textured surface with increased surface area, directly addressing the need for higher capacitance without requiring complex three-dimensional structures like nanowires or porous metals
Solution Approach 2:
The patent replaces mechanical/physical structuring methods (such as building nanowires or creating porous structures) with chemical processes (oxidation-reduction cycles) to achieve surface texturing. This substitution of chemical processes for mechanical structuring simplifies the manufacturing approach while still achieving the desired surface area increase
2Quantity of substance
If conventional methods (nano wires, nano tubes, porous metal) are used to increase capacitor surface area, then capacitance is improved, but fabrication cost increases
Solution Approach 1:
The patent employs inexpensive chemical reagents (oxidizing agents and reducing agents) that can be easily applied and removed, replacing expensive nanofabrication materials like nanowires, nanotubes, or porous metals. The chemical processes use readily available materials that leave no permanent expensive structures, achieving surface texturing at lower material cost
Solution Approach 2:
The oxidation-reduction process is self-limiting and self-regulating, where the chemical reactions naturally terminate when the surface transformation is complete. The process uses the substrate itself as the reaction medium, eliminating the need for complex equipment or expensive external processing steps required by conventional nanofabrication methods
3Quantity of substance
If nanotextured surfaces are formed through oxidation and reduction, then surface area and capacitance are improved, but process steps are added
Solution Approach 1:
The patent combines the oxidation and reduction steps into an integrated sequential process where the second step reverses and refines the first step. This merging of complementary chemical processes achieves the desired nanotextured surface while minimizing the number of discrete process modules required, as the two steps work together to produce the final surface morphology in a coordinated manner
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 nanotextured surfaces enhance capacitor performance by increasing surface area, leading to higher capacitance, cost-effective fabrication, and versatile integration into semiconductor elements, with benefits including high yield and compatibility with back-end-of-line processes.
Implementation Method 1
oxidizing the metal in the first conductive layer to form a metal oxide. At least part of the metal oxide forms nanograins in the first conductive layer
Implementation Method 2
reducing the metal oxide to the metal to form a nanotextured metal surface
Implementation Method 3
using methods like plasma ashing
Implementation Method 4
forming gas annealing
Data Source
AI summary
Electrodes for a capacitor having nanotextured surfaces is disclosed. The nanotextured surfaces comprise nanograins of the metal and are fabricated by oxidizing and reducing a metal in the electrodes. The nanotextured surfaces significantly increase surface areas of the electrodes, as such improves a capacitance of the capacitor. The fabrication method can produce stacked capacitors with horizontally oriented electrodes or vertically oriented electrodes. The fabrication method may be of low cost and may produce high performance capacitors.