Sharp Kabushiki Kaisha Corporation

Yuji Nishi

Nobuyoshi Awaya

Toshimasa Suzuki

Keizo Sakiyama

Hidetoshi Masuda

Yukio Tamai

Shinji Kobayashi

Masayuki Fujimoto

Hidechika Kawazoe

Kohji Inoue

Yuji Matsushita

Naoto Hagiwara

In a nonvolatile semiconductor memory device including a variable resistive element formed by sequentially stacking a lower electrode, a variable resistor with a perovskite-type crystal structure, and an upper electrode, at least one of the lower electrode and the upper electrode is a particulate electrode configured to include a particulate conductor aggregate so that the contact area with the variable resistor at an interface is effectively reduced to realize high initial resistance of the variable resistive element. Further, a film of the variable resistor is preferably formed so as to be in a highly crystalline state.

Nonvolatile semiconductor memory device comprising a variable resistive element containing a perovskite-type crystal structure

There is provided an EPIR device which is excellent in mass productivity and high in practical utility. The EPIR device includes a lower electrode layer, a CMR thin film layer and an upper electrode layer which are laminated in this order on any of various substrates. A Pt polycrystal thin filmforming the lower electrode layer includes columnar Pt crystal grainsA,B,C, . . . and over 90% of these crystal grains is oriented to a (1 1 1) face. Columnar PCMO crystal grain groupsA,B,C, . . . are respectively locally grown epitaxially on the respective outermost surfaces of the Pt crystal grainsA,B,C, . . . . Then, the crystal faces of the crystal grains included in the PCMO crystal grain groupsA,B,C, . . . and vertical in the substrate surface normal direction are any one of (1 0 0), (1 1 0)and (1 1 1)planes.

EPIR device and semiconductor devices utilizing the same

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Gumma-gun, Japan

Yuji Nishi