Macrocrystalline Refractory Cathode Ion Source Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ion sources employing refractory materials face issues with component erosion and efficiency changes over time, leading to unstable output and reduced performance in applications like ion assisted deposition and beamline implanters.
Innovation Solution
The development of ion sources with components made from refractory metals having a macrocrystalline structure, achieved through low-mass ambient annealing at elevated temperatures, which transforms microcrystalline components into macrocrystalline ones with improved properties such as lower work function and higher current output.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If refractory materials are used for ion source components, then component strength and erosion resistance are improved, but output stability and efficiency deteriorate over time
Solution Approach 1:
The patent changes the crystalline structure parameter of refractory materials from microcrystalline to macrocrystalline through controlled annealing processes. This parameter change results in materials with lower work function and more stable emission characteristics, resolving the contradiction between maintaining strength and improving output stability.
2Loss of substance
If refractory materials are used for ion source components, then erosion resistance is improved, but component efficiency deteriorates over time
Solution Approach 1:
The patent transforms the crystalline structure parameter of refractory materials through annealing, creating macrocrystalline structures that simultaneously provide erosion resistance and maintain efficient electron emission properties over extended operational periods.
3Ease of manufacture
If microcrystalline refractory materials are used, then manufacturing is easier, but work function and current output are suboptimal
Solution Approach 1:
The patent applies preliminary annealing treatment to transform microcrystalline materials into macrocrystalline structures before final assembly and use. This preliminary action optimizes the material properties for electron emission while maintaining manufacturing feasibility.
Solution Approach 2:
The patent changes the crystalline structure parameter through controlled thermal annealing, transforming materials from microcrystalline to macrocrystalline state. This parameter change optimizes both work function and current output while remaining compatible with existing manufacturing processes.
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 macrocrystalline structure results in more stable plasma emission, increased current output, and extended operational life of ion source components, reducing erosion and maintaining efficiency over time.
Implementation Method 1
a cathode disposed in the ion source chamber and configured to emit electrons to generate a plasma within the ion source chamber
Implementation Method 2
annealing the component body in low-mass ambient at an annealing temperature of at least 1000° C., for a dwell time of at least several hours
Data Source
AI summary
An ion source is provided. The ion source may include an ion source chamber, and a cathode disposed in the ion source chamber and configured to emit electrons to generate a plasma within the ion source chamber, the cathode comprising a refractory metal, wherein the refractory metal comprises a macrocrystalline structure.