EP0807965A2
Expired / Lapsed
EP
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Method of manufacturing layered ferroelectric Bi containing film
Assignee: Kojundo Kagaku Kenkyusho KK
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Filing: 1997-05-13
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Granted: —
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Expires: 2017-05-13
Abstract
Abstract A method of forming a Bi-layered ferroelectric thin film on a substrate with good reproducibility, using a mixed composition of a Bi-containing organic compound and a metal polyalkoxide compound by at least one technique selected from the group consisting of molecular deposition such as CVD, and spincoat-sintering. <IMAGE>
Inventors
- 👤 Yukoh Hochido
- 👤 Hidekimi Kadokura
- 👤 Masamichi Matsumoto
- 👤 Koji Arita
- 👤 Masamichi Azuma
- 👤 Tatsuo Otsuki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 04:36
CPC Classifications
C; C23; C23C; C23C18/00; C23C18/02; C23C18/12; C23C18/1204; C23C18/1208; C23C18/1216; H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6938; H10P14/69398; C23C16/00; C23C16/22; C23C16/30; C23C16/40; C23C18/125; C23C18/1279; H10D; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10D1/684; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6334; H10P14/6336; H10P14/6338; H10P14/6342; H10P14/66; H10P14/668
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
44 words
A method of producing a Bi-layered ferroelectric thin film on a substrate, comprising the steps of: mixing a Bi-containing organic compound and a metal polyalkoxide compound; and forming a Bi-layered ferroelectric thin film on the substrate by deposition of the mixture onto the substrate.
Claim 2
Dependent Claim
22 words
The method of claim 1, wherein said deposition is selected from the group consisting of molecular deposition, spincoat-sintering, and chemical vapor deposition.
Claim 3
Dependent Claim
157 words
The method of claim 1, wherein the formed Bi-layered ferroelectric thin film is described by the following Formula 1: (Bi 2 O 2 ) 2+ ((A 1 ) m1 (A 2 ) m2 ···(A n ) mn (B 1 ) s1 (B 2 ) s2 ···(B t ) st O 3p+1 ) 2- Formula 1 where A 1 ,A 2 ,···,A n is a cationic element and also at least one simple substance or a mixture selected from the group consisting of Ba, Bi, Sr, Pb, La, and Ca; B 1 , B 2 ,···,B t is a cationic element and at least one simple substance or a mixture selected from the group consisting of Ti, Zr, Ta, Mo, W, and Nb; p is an integer from 1 to 5; m1,m2,···,mn is a non-negative real number which meets the equation of m1+m2+···+mn=p-1 ; and s1,s2,···,st is a non-negative real number which meets the equation of s1+s2+···+st=p .
Claim 4
Dependent Claim
124 words
The method of claim 1, wherein the metal polyalkoxide compound is described by the following Formula 2: A i (B j ((OR j1 )(OR j2 )···(OR j6 )))(B k ((OR k1 )(OR k2 )···(OR k6 ))) Formula 2 where A i is a cationic element and at least one simple substance or a mixture selected from the group consisting of Ba, Bi, Sr, Pb, La, and Ca; B j and B k are cationic elements which are identical or different from each other, and also simple substances or mixtures selected from the group consisting of Ti, Zr, Ta, Mo, W, Nb; and R j1 ,R j2 ,···R j6 ,R k1 ,R k2 ,···R k6 is an alkyl group having carbons from 1 to 12.
Claim 5
Dependent Claim
12 words
The method of claim 1, wherein the deposition comprises chemical vapor deposition.
Claim 6
Dependent Claim
30 words
The method of claim 1, wherein the mixture comprises 1 to 99 weight % of the Bi-containing organic compound and 99 to 1 weight % of the metal polyalkoxide compound.
Claim 7
Dependent Claim
44 words
The method of claim 4, wherein each metal alkoxide compound of R j1 , R j2 , ···R j6 , R k1 , R k2 , ···R k6 represented by Formula 2 comprises at least one of an ethyl group or an isopropyl group.
Claim 8
Dependent Claim
64 words
The method of claim 4, wherein A i of the metal alkoxide group represented by Formula 2 comprises at least one element selected from the group consisting of Sr and Ba; B j comprises at least one element selected from the group consisting of Nb and Ta; and B k comprises at least one element selected from the group consisting of Nb and Ta.
Claim 9
Dependent Claim
28 words
The method of claim 1, wherein the Bi-containing organic compound comprises at least one compound selected from the group consisting of Bi tertiary butoxide and Bi tertiary pentoxide.
Claim 10
Dependent Claim
47 words
The method of claim 5, wherein the chemical vapor deposition comprises dissolving the Bi-containing organic compound and the metal alkoxide compound represented by Formula 2 in an organic solvent to form a solution; vaporizing the solution to form a gas; and applying the gas on the substrate.
Claim 11
Dependent Claim
11 words
The method of claim 10, wherein the organic solvent comprises tetrahydrofuran.
Claim 12
Dependent Claim
28 words
The method of claim 10, wherein the chemical vapor deposition comprises optical chemical vapor deposition to irradiate ultraviolet rays to the pyrolitic atmosphere of the source material gas.
Claim 13
Dependent Claim
24 words
The method of claim 10, wherein the chemical vapor deposition comprises plasma chemical vapor deposition to plasma-excite the gas when the gas is pyrolyzed.
Claim 14
Dependent Claim
49 words
The method of claim 1, wherein the spincoat-sintering comprises: dissolving the Bi-containing organic compound and the metal alkoxide compound represented by Formula 2 in an organic solvent to form a solution; coating the solution on the substrate and drying the coating; and sintering the coating under an oxygen atmosphere.
Claim 15
Dependent Claim
11 words
The method of claim 14, wherein the organic solvent comprises tetrahydrofuran.
Claim 16
Dependent Claim
17 words
The method of claim 1, wherein an organic compound containing Pb is further added to the mixture.
Claim 17
Dependent Claim
38 words
The method of claim 16, wherein the amount of the Pb-containing organic compound is from 1×10 -5 to 200 weight parts when the mixed composition comprising Bi-containing organic compound and the metal polyalkoxide compound is 100 weight parts.
Claim 18
Dependent Claim
41 words
The method of claim 16, wherein the formed Bi-layered ferroelectric thin film is represented by the following Formula 3: (Sr a Ba b Pb c )(Nb x Ta y )Bi 2 O 9 Formula 3 where a+b+c=1 , 0<c<1, x+y=2 .
Claim 19
Dependent Claim
69 words
The method of claim 16, wherein the Bi-layered ferroelectric thin film is applied on the substrate by chemical vapor deposition, using a mixture comprising an alkoxide compound represented by the following Formula 4 and a Pb-containing organic compound, (Sr d Ba e )[(Nb p Ta q )(OR) 6 ] 2 Formula 4 where d+e=1 , p+q=1 , R is C 2 H 5 or CH(CH 3 ) 2 ).
Claim 20
Dependent Claim
28 words
The method of claim 16, wherein the Pb-containing organic compound comprises at least one compound selected from the group consisting of Pb tertiary butoxide and Pb oxotertiary butoxide.
Claim 21
Dependent Claim
28 words
The method of claim 16, wherein the Bi-containing organic compound comprises at least one compound selected from the group consisting of Bi tertiary butoxide and Bi tertiary pentoxide.
Claim 22
Dependent Claim
26 words
The method of claim 19, wherein the chemical vapor deposition comprises optical chemical vapor deposition to irradiate ultraviolet rays to the pyrolitic atmosphere of the gas.
Claim 23
Dependent Claim
24 words
The method of claim 19, wherein the chemical vapor deposition comprises plasma chemical vapor deposition to plasma-excite the gas when the gas is pyrolyzed.
Claim 24
Dependent Claim
11 words
The method of claim 1, wherein the substrate is a semiconductor.
Claim 25
Dependent Claim
17 words
The method of claim 1, wherein the Bi-layered ferroelectric thin film is 1nm to 10 µm thick.
References Cited (Backward Citations)
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