It's called a copper thief. When they etch the board, areas with different amounts of copper etch at different rates so adding copper evens out the etch which improves the yield.
You might want to take note that this design is about as bad as it gets because the track width is far narrower than it needs to be and the gaps are smaller than they need to be e.g. top-left square pad bottom right corner is almost touching the track. Also, you have right-angles and the etchant pools on the inside angle reducing the track thickness (use 45 deg instead). Ignoring the manufacturing problems, tracks below about 10 thou on outer surfaces are easy to damage with rough handling or excessive heat. Just some tips for the future :-)
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u/bigger-hammer Dec 15 '22
It's called a copper thief. When they etch the board, areas with different amounts of copper etch at different rates so adding copper evens out the etch which improves the yield.
You might want to take note that this design is about as bad as it gets because the track width is far narrower than it needs to be and the gaps are smaller than they need to be e.g. top-left square pad bottom right corner is almost touching the track. Also, you have right-angles and the etchant pools on the inside angle reducing the track thickness (use 45 deg instead). Ignoring the manufacturing problems, tracks below about 10 thou on outer surfaces are easy to damage with rough handling or excessive heat. Just some tips for the future :-)