Inner Layer Polarities

Some CAM suites offer the ability to generate solid plane layers for inner layers.

Often if this option is selected the gerber file will be output in negative polarity or, put another way, rather than the data output representing copper features the drawn data represents the areas of the layer that are absent of copper.

When preparing your order for production commonly we rely on context clues such as file names, file headers, or the inclusion of thermal elements in the design to determine a layer's polarity. Without these indicators or readme file stating the intended polarity we require additional information to ensure your design is manufactured as intended.

If we are unable to determine the intended polarity of a layer we will contact you for clarification to ensure that your board is built exactly to your specification.

This is an example of a plane layer with thermals in positive polarity. As is any drill hits in the center of these thermals wouldn't make connection to the layer.

This is an example of the same plane layer now in negative polarity which allows the thermals and split plane to function as intended.