A co-extrusion device includes at least one first inlet port to receive a first material, at least one second inlet port to receive a second material, a first combining channel arranged to receive the first material and the second material and combine the first and second materials into a first combined flow flowing in a first direction, a splitter channel arranged to receive the first combined flow and to split the first combined flow into at least two split flows in a second direction at least partially orthogonal to the first direction, wherein each split flow consists of the first and second materials, a second combining channel arranged to receive the split flows and combine the split flows into a second combined flow in the first direction, and at least one exit orifice arranged to allow the materials to exit the device as a single flow.

A method for depositing a structure comprising interdigitated materials includes merging flows of at least two materials in a first direction into a first combined flow, dividing the first combined flow in a second direction to produce at least two separate flows, wherein the second direction is perpendicular to the first direction, and merging the two separate flows into a second combined flow.