Solar Cell Back Electrode Recess for Reduced Contact Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Solar cell apparatuses face challenges in achieving improved electric characteristics due to limited contact area and resistance between connection wires and back electrode layers, which affects overall efficiency and photoelectric conversion.
Innovation Solution
The solar cell apparatus includes a substrate with a back electrode layer, an intermediate layer, a light absorbing layer, and a front electrode layer, where a connection wire directly contacts the back electrode layer through a recess and intermediate layer, increasing the contact area and reducing resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the connection wire is connected to the back electrode layer through a conventional flat interface, then the structure is simple, but the contact area is limited and resistance is high
Solution Approach 1:
The back electrode layer is formed with a recess having a curved inner surface instead of a flat interface. This curvature increases the contact area between the connection wire and the back electrode layer, thereby improving the connection characteristic and reducing resistance.
Solution Approach 2:
The connection wire is positioned to extend into the recess of the back electrode layer, transitioning from a surface-level connection to a three-dimensional embedded connection. This dimensional change significantly increases the contact area and improves electrical connection reliability.
2Reliability
If the connection wire directly contacts the back electrode layer through the recess, then the contact area increases and resistance decreases, but the manufacturing process becomes more complex
Solution Approach 1:
The recess formation process is combined with the existing back electrode layer fabrication process. The recess is formed by removing material during the standard manufacturing sequence, merging the complexity of creating a curved interface with the established production workflow rather than adding a separate complex assembly step.
3Reliability
If an intermediate layer is added between the back electrode layer and light absorbing layer, then the electric characteristics improve, but the manufacturing steps increase
Solution Approach 1:
The intermediate layer is formed during the preliminary stages of device fabrication, before the light absorbing layer is deposited. This preliminary formation of the intermediate layer with specific material composition allows subsequent processing steps to proceed efficiently without requiring additional complex operations.
Data Source
AI summary
Disclosed are a solar cell apparatus and a method for manufacturing the same. The solar cell apparatus includes a substrate; a back electrode layer on the substrate; a light absorbing layer on the back electrode layer; a front electrode layer on the light absorbing layer; and a connection wire extending from the front electrode layer and connected to the back electrode layer through the light absorbing layer, wherein the connection wire directly makes contact with an inner side of a recess formed in the back electrode layer.