Patent ID: 8889478
Filing Date: 2014-11-18
Classification: H01L

Abstract:
1. A method for manufacturing a nonvolatile semiconductor memory element, the method, comprising: depositing a first conductive film above a substrate; depositing a semiconductor film on the first conductive film; depositing a second conductive film on the semiconductor film; depositing a third conductive film on the second conductive film; depositing, on the third conductive film, a variable resistance film including a plurality of layers having different oxygen content atomic percentages; depositing a fourth conductive film on the variable resistance film; forming a top electrode of a variable resistance element by patterning the fourth conductive film; forming a variable resistance layer of the variable resistance element by patterning the variable resistance film; forming a bottom electrode of the variable resistance element by patterning the third conductive film; forming a top electrode of a metal-semiconductor-metal (MSM) diode element by patterning the second conductive film; forming a semiconductor layer of the MSM diode element by patterning the semiconductor film; forming a bottom electrode of the MSM diode element by patterning the first conductive film; and after the forming of a top electrode of a variable resistance element and at least before the forming of a top electrode of an MSM diode element, oxidizing to insulate a portion of the variable resistance film in a region around an end face of the variable resistance layer, wherein, in the oxidizing, the second conductive film before the patterning serves as a barrier to oxygen diffusion to reduce oxidization of the semiconductor film.