Pattern transfer of an extreme ultraviolet imaging layer via flood exposure of contact mask layer (EUV CML)

摘要

A method of forming a device feature using an extreme ultraviolet (EUV) imaging layer (or a sub-deep ultraviolet imaging layer) and one or more other masks layers. The method includes forming a device feature layer; forming a photoresist layer over the device feature layer; forming a contact mask layer (CML) over the photoresist layer; forming an extreme ultraviolet (EUV) imaging layer over the CML; forming a first opening through the EUV imaging layer to expose a first underlying region of the CML; forming a second opening through the CML to expose a second underlying region of the photoresist layer, wherein the second opening is situated directly below the first opening; forming a third opening through the photoresist layer to expose a third underlying region of the device feature layer, wherein the third opening is situated directly below the second opening; forming a fourth opening through the device feature material layer, wherein the fourth opening is situated directly below the third opening.