Plasmon Generator Manufacturing via Etching Mask Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for manufacturing plasmon generators struggle to produce a front end face with a width of 40 nm or smaller due to limitations in photolithography, leading to instability and potential stripping of the plasmon generator from the underlying layer.
Innovation Solution
A manufacturing method involving the formation of an etching mask with a structure having a second opening smaller than the first opening, allowing for the precise etching of a dielectric layer to create an accommodation part for the plasmon generator, which is then formed with a propagation part and a width changing portion to achieve a near-field light generating part with a small width.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If photolithography is used to manufacture the plasmon generator, then the manufacturing process is simple and widely applicable, but the front end face width cannot be reduced to 40 nm or smaller
Solution Approach 1:
The manufacturing process is segmented into multiple sequential steps: forming a mandrel with first width, depositing a first sacrificial layer, forming a second mandrel with second width (smaller than first), depositing a second sacrificial layer, and finally forming the plasmon generator. This multi-stage segmentation enables achieving sub-40nm dimensions that cannot be obtained through single-step photolithography.
Solution Approach 2:
Mandrels and sacrificial layers are formed in advance before the actual plasmon generator structure is created. The first mandrel and first sacrificial layer prepare the initial pattern, then the second mandrel and second sacrificial layer further refine the dimensions. These preliminary actions enable precise control of the final front end face width below the photolithography resolution limit.
2Manufacturing precision
If the front end face width is reduced to increase near-field light intensity, then the spot diameter decreases and recording density increases, but the plasmon generator becomes unstable and prone to stripping
Solution Approach 1:
Sacrificial layers are deposited beforehand at critical interfaces: the first sacrificial layer between the lower substrate and upper structure, and the second sacrificial layer providing additional cushioning. These pre-deposited layers prevent direct stress concentration at the narrow front end face, cushioning against stripping forces that would otherwise occur due to the reduced width.
Solution Approach 2:
The plasmon generator structure exhibits varying width along its length: the front end face has narrow width (5-40 nm) for high light intensity, while the rear portion maintains larger width for structural stability. The sacrificial layers are strategically positioned to provide localized support where needed, creating non-uniform structural quality that optimizes both performance and reliability.
3Illumination intensity
If the width and height of the front end face are reduced to achieve smaller spot diameter, then near-field light intensity increases, but the manufacturing precision requirements exceed conventional photolithography capabilities
Solution Approach 1:
The patent replaces photolithography (optical/mechanical system with resolution limits) with a deposition-based manufacturing approach. Atomic layer deposition or chemical vapor deposition methods are used to form mandrels and sacrificial layers with atomic-level precision, substituting the optical limitation with a chemical vapor deposition process that can achieve sub-nanometer control over layer thickness and structure dimensions.
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 stable manufacture of a plasmon generator with a front end face width of 5 to 40 nm, overcoming the limitations of photolithography and preventing stripping issues, while maintaining sufficient near-field light intensity and spot diameter.
Implementation Method 1
U.S. Pat. No. 7,911,883 discloses a technology in which the surface of the core of a waveguide and the surface of a plasmon generator are arranged to face each other with a gap therebetween, and evanescent light that occurs at the surface of the core based on the light propagating through the core is used to excite surface plasmons
Implementation Method 2
evanescent light that occurs at the surface of the core based on the light propagating through the core is used to excite surface plasmons on the plasmon generator
Implementation Method 3
The surface plasmons excited on the plasmon generator propagate along the surface of the plasmon generator to reach the near-field light generating part
Implementation Method 4
the surface plasmons concentrate at the near-field light generating part, and the near-field light generating part generates near-field light based on the surface plasmons
Data Source
AI summary
A method of manufacturing a plasmon generator includes the steps of: forming an etching mask on a dielectric layer; forming an accommodation part by etching the dielectric layer using the etching mask; and forming the plasmon generator to be accommodated in the accommodation part. The step of forming the etching mask includes the steps of: forming a patterned layer on an etching mask material layer, the patterned layer having a first opening that has a sidewall; forming a structure by forming an adhesion film on the sidewall, the structure having a second opening smaller than the first opening; and etching a portion of the etching mask material layer exposed from the second opening.