Britannica Sources used in this answer

Why are the front metal contacts on a solar cell arranged in a thin grid pattern?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Diagram of a solar cell showing labeled layers, including a front electrical contact grid, antireflection layer, absorber layer, back junction layer, and back electrical contact layer, with arrows indicating light entering and terminals connecting to a circuit. — solar cell A commonly used solar cell structure. In many such cells, the absorber layer and the back junction layer are both made of the same material.

The front metal contacts of a solar cell are arranged in a thin grid pattern to balance two competing requirements: the need to collect electric current and the need to maximize light absorption.1

Because the metal used for these contacts is opaque, it blocks incoming sunlight from reaching the semiconductor layers where energy conversion occurs. To minimize this obstruction, the grid lines are designed to be as thin and widely spaced as possible. However, they must remain dense enough to efficiently collect the current generated by the cell and carry it to an external load. Unlike the front contacts, the back electrical contact layer does not face this restriction and typically covers the entire rear surface of the cell to ensure optimal conductivity.1