Evaporation Boat Pyramid Surface for Uniform Wetting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing evaporation boats in vacuum band metallization systems experience uneven wetting and corrosion due to the preferred direction of grooves on the evaporator surface, leading to low evaporation rates and short service life.
Innovation Solution
A pyramidally structured evaporator surface created by mechanically machining in two perpendicular directions, increasing the surface area for evaporation and ensuring homogeneous wetting, which reduces corrosion and extends service life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If grooves are provided on the evaporator surface to improve wetting, then wetting behavior improves, but uneven wear and corrosion occur due to preferred direction
Solution Approach 1:
The evaporator surface is segmented into multiple groove systems oriented in different directions (first grooves in first direction, second grooves in second direction perpendicular to the first). This segmentation ensures that liquid metal can wet the surface uniformly from multiple directions, preventing accumulation at specific locations and distributing wear and corrosion more evenly across the entire surface, thereby extending service life while maintaining reliable wetting behavior
Solution Approach 2:
Different regions of the evaporator surface are equipped with grooves having different orientations and potentially different characteristics (width, depth, length). The first grooves and second grooves can have locally optimized dimensions to address specific wetting needs in different areas, while collectively ensuring uniform overall wetting and preventing localized overheating and corrosion that would reduce service life
2Productivity
If direct passage of current is used to heat the evaporation boat, then evaporation rate increases, but hot metal corrosion damages the boat surface
Solution Approach 1:
The grooves on the evaporator surface are designed to utilize and distribute the liquid metal in a way that converts the harmful corrosive effect into a beneficial protective layer. The grooves ensure uniform distribution of liquid metal across the surface, creating a more homogeneous protective layer that reduces localized corrosion while maintaining the high temperatures needed for high evaporation rates through direct current passage
3Productivity
If the evaporator surface area is increased to improve evaporation rate, then productivity increases, but device complexity increases
Solution Approach 1:
Instead of simply increasing the evaporator surface area in two dimensions by expanding the boat size, the invention adds a third dimension by creating grooves with specific width, depth, and length characteristics. This三维 structuring increases the effective surface area available for metal wetting and evaporation without proportionally increasing the overall device size or complexity, as the grooves are integrated into the existing boat structure
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 pyramidally structured surface enhances evaporation rates and service life by ensuring uniform wetting and temperature distribution, reducing the need for frequent replacements and allowing for situation-dependent evaporation process control.
Implementation Method 1
the evaporator surface has a pyramidally structured surface which can be created by mechanically machining the evaporator surface in two mutually perpendicular machining directions
Implementation Method 2
This is explained by the so-called capillary effect, which 'pulls' the liquid aluminum that is in the grooves during evaporation toward the longitudinal ends of the grooves and is thus expected to improve the wetting of the surface
Implementation Method 3
These are heated to temperatures of approximately 1700° C. using a direct passage of current
Implementation Method 4
At the same time, there is additional reflection of thermal radiation on the side walls of the grooves. This is in turn expected to lead to an increased temperature of the evaporator surface and thus enable a higher evaporation rate
Data Source
AI summary
The invention relates to an evaporation boat comprising an evaporator body, wherein the evaporator body comprises an evaporator surface which extends along a longitudinal direction of the evaporator body. The evaporator surface has a pyramidally structured surface which can be created by mechanically machining the evaporator surface in two mutually perpendicular machining directions. The pyramidally structured surface comprises a plurality of structural elements which are directly adjacent to one another and have a substantially rectangular bottom surface and lateral surfaces which taper conically to a top surface or point.