Patent ID: 7923305
Filing Date: 2011-04-12
Classification: H01L

Abstract:
1. A method of making a device, comprising: providing a switching material layer; providing a semiconductor seed layer over the switching material layer; forming the underlying layer over the switching material layer; forming a first sacrificial layer over the underlying layer; forming a first photoresist layer over the first sacrificial layer; patterning the first photoresist layer to form first photoresist features; rendering the first photoresist features insoluble to a solvent; forming a second photoresist layer over the first photoresist features; patterning the second photoresist layer to form second photoresist features; etching the first sacrificial layer using both the first and the second photoresist features as a mask to form first sacrificial features; forming a spacer layer over the first sacrificial features; etching the spacer layer to form spacer features and to expose the first sacrificial features; removing the first sacrificial features; etching the underlying layer using the spacer features as a mask to form openings in the underlying layer; and forming semiconductor features in the openings in the underlying layer; removing the underlying layer; etching the semiconductor seed layer using the semiconductor features as a mask; etching the switching material layer using the semiconductor features as a mask to form switching material features after the step of removing the underlying layer; and forming an insulating filler layer between the semiconductor features after the step of etching the switching material layer.