	US 7,485,937 B2
	Tunnel junction device
Yoshinori Tokura, Tsukuba (Japan); Masashi Kawasaki, Tsukuba (Japan); Hiroshi Akoh, Tsukuba (Japan); Hiroyuki Yamada, Tsukuba (Japan); Yuji Ishii, Tsukuba (Japan); Hiroshi Sato, Tsukuba (Japan); and Yoshio Kaneko, Chiba (Japan)
Assigned to National Institute of Advanced Industrial Science and Technology, Tokyo (Japan); and Japan Science and Technology Agency, Kawaguchi-shi (Japan)
Appl. No. 10/591,246 PCT Filed Feb. 25, 2005, PCT No. PCT/JP2005/003099 § 371(c)(1), (2), (4) Date May 08, 2007, PCT Pub. No. WO2005/086250, PCT Pub. Date Sep. 15, 2005.
Claims priority of application No. 2004-062073 (JP), filed on Mar. 05, 2004.
Prior Publication US 2007/0212572 A1, Sep. 13, 2007
This patent is subject to a terminal disclaimer.
Int. Cl. H01L 43/08 (2006.01)

U.S. Cl. 257—421 [257/422]

10 Claims

1. A tunnel junction device, comprising:

a first electrode;

a second electrode; and

an electrically insulating layer arranged between the first electrode and the second electrode;

wherein:

the first electrode comprises an A_1-xB_xM_1-yM′_yO_3-δ oxide ferromagnetic (including ferrimagnetic) electroconductive solid material, wherein:

x and y satisfy the conditions: 0≤x≤1 and 0≤y≤1;

δ represents an oxygen deficiency;

A represents an element selected from the group consisting of Ca, Sr, Ba, and other alkaline earth elements, La and other rare earth elements, and elements including Y, Bi, and Pb;

B represents an element that is different from A, selected from the group consisting of Ca, Sr, Ba, and other alkaline earth elements, La and other rare earth elements, elements including Y, Bi, and Pb;

M represents an element selected from the group consisting of Mn, Fe, Co, Ni, or Cu and other transition metal elements; and

M′ represents an element selected from the group consisting of Mn, Mn, Fe, Co, Ni, or Cu and other transition metal elements M′ being different from “M”; and

the second electrode comprises an A_1-x′B_x′M_1-y′M′_y′O_3-δ oxide ferromagnetic (including ferrimagnetic) electroconductive solid material having a component ratio y′ that is not equal to y, wherein x′ and y′ satisfy the conditions: 0≤x′≤1, 0<y′≤1.