Methods of manufacturing a semiconductor device using a mask

Abstract

A method of manufacturing a semiconductor device includes forming a first sacrificial and first active layer on a substrate; forming a first mask pattern on a portion of the substrate; etching the first sacrificial and first active layer partially using the first mask pattern to expose a portion of a top surface of the substrate; forming a semiconductor layer on the exposed top surface of the substrate; forming sacrificial layers and active layers on the first active and semiconductor layer, the active layers including an uppermost second active layer; forming a second mask pattern on a portion of the second active layer; forming a trench using the second mask pattern, the trench defining a first and second active pattern; and removing the sacrificial layers to form a first and second channel patterns on the first and second active patterns, respectively, wherein the first active pattern includes the semiconductor layer.