Production of chemical reactors

A chemical reactor implemented on a substrate, the chemical reactor comprising:

• one or more effective channels for transporting a liquid and/or gas during use of the chemical reactor, the effective channels comprising pillar structures;
• an input connected to one of the one or more effective channels to allow the liquid and/or gas into the effective channels;
• an output connected to one of the one or more effective channels to remove at least one component of the liquid and/or gas from the effective channels;
• and
• a structured area positioned adjacent to an effective channel of the one or more effective channels located at an edge of the chemical reactor, the structured area not being fluidly connected to the one or more effective channels, and the structured area including a dummy channel, the dummy channel being a channel that has no connection to the one or more effective channels and that has no input or output.