Wiring structure and method of manufacturing the same, semiconductor device, multilayer wiring structure and method of manufacturing the same, semiconductor element mounting substrate, method of forming pattern structure, imprint mold and method of manufacturing the same, imprint mold set, and method of manufacturing multilayer wiring board

A multilayer wiring structure formed on a base material, comprising:

• insulating pattern structures formed in multiple layers;
• and
• a wiring layer embedded in each of the pattern structures,
• wherein each wiring layer has a pad portion and an interlayer connection via connected to the pad portion, and
• the interlayer connection via has a stepped shape including at least two steps.

A method of forming a pattern structure, comprising the steps of:

• supplying an insulating resist onto a transfer base material;
• preparing a mold which has a mold base material and a projected portion located at a main surface of the mold base material, and bringing the mold and the transfer base material close to each other to spread the insulating resist between the mold and the transfer base material, thereby forming an insulating resist layer;
• curing the insulating resist layer to form an insulating material layer;
• separating the mold from the insulating material layer;
• and
• developing the insulating material layer to obtain a state in which an insulating pattern structure having a recess for forming a pad portion and a through-hole for forming an interlayer connection via, the through-hole located in the recess, is located on the transfer base material,
• wherein the through-hole has a stepped shape including at least two steps.