Fishing – trapping – and vermin destroying
Patent
1994-06-15
1995-06-20
Hearn, Brian E.
Fishing, trapping, and vermin destroying
437 52, 20419215, 20419222, H01L 2102
Patent
active
054260752
ABSTRACT:
A semiconductor manufacturing method is directed to forming a ferroelectric film, and in particular a ferroelectric film of the bismuth layer structure type, that has a significant component of reversible polarization perpendicular to the plane of the electrodes. The manufacturing method is conducted at low temperatures on commercially suitable electrodes and is compatible with conventional CMOS fabrication techniques. A ferroelectric strontium-bismuth-tantalate ("SBT") film is formed using two sputtering targets. A first sputtering target is comprised primarily of bismuth oxide (Bi.sub.2 O.sub.3) and a second sputtering target is comprised primarily of SBT. An initial layer of bismuth oxide is formed on the bottom electrode of a ferroelectric capacitor stack. The initial layer of bismuth oxide is directly followed by a sputtered layer of SBT. A second layer of bismuth oxide is then applied and the layers are alternated in a "layer cake" fashion containing a plurality of layers until a desired thickness of the film is attained. At the end of the deposition, a crystallization anneal is performed to make the film ferroelectric. Once the ferroelectric film is in place, the top electrode is formed and the remaining processing steps are completed.
REFERENCES:
patent: 5041200 (1991-08-01), Ishii
M. H. Francombe, W. J. Takei & N. P. Formigoni, "Growth and Properties of Epitaxial Films of Ferroelectric Bismuth Titanate", Air Force Avionics Laboratory, Feb. 1970.
M. H. Francombe, W. J. Takei & S. Y. Wu, "Growth and Properties of Epitaxial Films of Ferroelectric Bismuth Titanate", Air Force Avionics Laboratory, Apr. 1970.
M. H. Francumbe & S. V. Krishnaswamy, Growth and Properties of piezoelectric and ferroelectric films:, J. Vac. Sci. Tech., A8(3), May, Jun. 1990.
K. Wasa & S. Hayakawa, Handbook of Sputter Deposition Technology-Principles, Technology and Application, pp. 220-221.
Spry "Dielectric Optical Switch" May 4, 1993 FIG. 1 & col. 3.
Davenport Thomas E.
Perino Stanley
Dang Trung
Hearn Brian E.
Johnson, Jr. Alexander C.
Meza Peter J.
Ramtron International Corporation
LandOfFree
Method of manufacturing ferroelectric bismuth layered oxides does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of manufacturing ferroelectric bismuth layered oxides, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of manufacturing ferroelectric bismuth layered oxides will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1844042