Solar Cell Marking via Laser Indentation and Etching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solar cell marking methods often position markings in edge areas that do not contribute to electricity generation, leading to minimized but still significant non-active regions, which can impair the solar cell's function and are difficult to read after manufacturing processes.
Innovation Solution
A solar cell marking method that positions markings in the active zone of the semiconductor wafer using laser-induced indentations, allowing for maximum active zone utilization and enabling easy reading with optoelectronic devices, while minimizing the impact on the solar cell's functionality by removing affected zones through etching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If markings are positioned in edge areas of solar cells, then markings can be made without interfering with electricity generation, but the active zone is reduced and markings become difficult to read after manufacturing processes
Solution Approach 1:
Instead of placing markings in the non-active edge areas as conventionally done, this patent inverts the approach by positioning markings directly in the active zone of the solar cell. The marking is created using laser-induced indentations that are subsequently etched, allowing the marking to be embedded within the active semiconductor material rather than on the periphery.
Solution Approach 2:
The marking is created early in the manufacturing process, before the solar cell undergoes subsequent processing steps. The laser-induced indentation and etching are performed on the semiconductor wafer before final assembly, ensuring the marking survives subsequent manufacturing processes and remains readable throughout the product life cycle.
2Area of stationary object
If laser radiation is used to create markings in the active zone, then maximum active zone utilization is achieved, but the laser energy may impair solar cell functionality
Solution Approach 1:
The patent converts the potentially harmful effect of laser radiation into a beneficial process. The laser energy, which could damage the semiconductor, is instead used to create controlled indentations that are then etched to form durable markings. The laser-induced modifications serve as templates for the final marking structure, transforming a harmful factor into the basis of the marking process.
Solution Approach 2:
The patent extracts or removes the zones affected by laser energy input through a subsequent etching process. By selectively removing the laser-modified material, the harmful effects of laser radiation are eliminated while retaining the marking information. This extraction process ensures that no degraded semiconductor material remains in the final product.
3Loss of information
If markings are created early in the manufacturing process, then traceability throughout production is improved, but the markings must withstand subsequent processing steps
Solution Approach 1:
The marking is created early in the manufacturing process, before the solar cell undergoes subsequent processing steps. The laser-induced indentation and etching are performed on the semiconductor wafer before final assembly, ensuring the marking survives subsequent manufacturing processes and remains readable throughout the product life cycle.
Solution Approach 2:
The patent creates a robust marking structure that is cushioned or protected against subsequent processing. The laser-induced indentation followed by etching creates a durable feature that is embedded in the semiconductor material, providing resistance to damage during subsequent manufacturing steps and ensuring long-term readability.
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 method maximizes the active zone of solar cells, ensures markings can be reliably read throughout the production and product life cycle, and maintains the solar cell's performance by avoiding impairment from laser radiation effects.
Implementation Method 1
the marking is produced in the form of at least one indentation (21) introduced into the wafer surface (10) and generated by means of laser radiation
Implementation Method 2
after the creation of the at least one depression, an etching step is provided in such a way that the zones on the wafer surface that are influenced by the input of energy are completely removed in the region of the depression
Data Source
Figure 1
Figure 2~3d
Figure 4
AI summary
The invention relates to a solar cell marking method, having the following steps: provision of a substrate having a substrate surface for producing a solar cell (1) which has an active zone (5), and production of at least one depression (21, 31) in the substrate surface using laser radiation, the at least one depression (21, 31) forming a marker (2, 3) for marking the solar cell (1), and the depression (21, 31) being produced before a solar cell production process is carried out or while a solar cell production process is being carried out. In line with the invention, the substrate is in the form of a semiconductor wafer having a wafer surface, and the marker (2, 3) is positioned on the wafer surface such that the marker (2, 3) is in the active zone (5) of the solar cell (1) formed from the semiconductor wafer. The invention also relates to a semiconductor wafer solar cell (1) whose marker is easily identifiable and hence is positioned so as to be reliably readable without this adversely affecting the operability of the solar cell (1).