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Claims  |
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We claim:
1. A semiconductor-type laminated ceramic capacitor with a grain boundary
insulated structure comprising a plurality of inner electrodes on the
surfaces of the grain boundary insulated, semiconductor type ceramic
sheets, the terminal of each of said inner electrodes being extended to
one edge of the corresponding ceramic sheet and said ceramic sheets being
laminated so that said terminals of said inner electrodes come to the
corresponding opposite edges of said ceramic sheets alternatively one by
one; and outer electrodes electrically connected to said terminals of
inner electrodes at opposite edges of each of said grain boundary
insulated, semiconductor type ceramic sheets, wherein said ceramic sheets
comprise of a material of the composition of Sr.sub.(1-x) Ca.sub.x
TiO.sub.3 containing excess Ti to make final molecular ratio of Ti to
Sr.sub.(1-x) Ca.sub.x in the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x
/Ti<1.00(where x is in the range of 0.001.ltoreq.x.ltoreq.0.2); at least
one or more kinds of the compounds selected from Nb.sub.2 O.sub.5,
Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3,
Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added
to said ceramic material to make their relative molar content in the range
from 0.05 to 2.0%; and Mn and Si are also included in said ceramic
material to the amount of their combined relative molar content,
converting into MnO.sub.2 and SiO.sub.2 respectively, in the range of 0.2
to 5.0%.
2. A semiconductor-type laminated ceramic capacitor with a grain
boundary-insulated structure according to claim 1, wherein said inner
electrode is made of at least one or more kinds of metals selected from
Au, Pt, Rh, Pd or Ni, or alloys or compositions thereof.
3. A semiconductor-type laminated ceramic capacitor with a grain
boundary-insulated structure according to claim 2, wherein said outer
electrode is made of at least one or more kinds of metals selected from
Pd, Ag, Ni, Cu or Zn, or alloys or compositions thereof.
4. A semiconductor-type laminated ceramic capacitor with a grain
boundary-insulated structure according to claim 1, wherein said outer
electrode is made of at least one or more kinds of metals selected from
Pd, Ag, Ni, Cu or Zn, or alloys or compositions thereof.
5. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure comprising the steps
of calcinating starting material of mixed powder in air or in nitrogen
atmosphere after grinding, mixing and drying said mixed powder; forming
raw sheets by dispersing said calcinated powder in a solvent with organic
binder and molding said dispersed powder, said calcinated powder being
re-ground before dispersing and after calcinating; printing a pattern of
inner electrode paste on the surfaces of said raw sheets, terminals of
said inner electrodes being extended to each of the corresponding opposite
edges of said raw sheets alternatively one by one (wherein patterns of
inner electrodes are not printed on uppermost and lowermost parts of raw
sheets); calcinating laminated body in air, said laminated body being
formed by laminating and compressing said raw sheets on which surfaces
patterns of inner electrode paste have been printed; sintering said
laminated raw sheets in reducing atmosphere or in nitrogen atmosphere
after calcination; re-oxidizing in air after sintering; and covering said
edges of sintered ceramic sheets with outer electrode paste and baking
after re-oxidation, terminals of inner electrodes being exposed to said
edges, wherein: said starting material of mixed powder comprises of a
material of the composition of Sr.sub.(1-x) Ca.sub.x TiO.sub.3 containing
excess Ti to make final molecular ratio of Ti to Sr.sub.(1-x) Ca.sub.x in
the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00 (where x is in the
range of 0.001.ltoreq.x.ltoreq.0.2); at least one or more kinds of the
compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2
O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2 O.sub.3, Y.sub.2
O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added to said starting material
to make their relative molar content in the range from 0.05 to 2.0%; and
Mn and Si are also included in said starting material to the amount of
their combined relative molar content, converting into MnO.sub.2 and
SiO.sub.2 respectively, in the range of 0.2 to 5.0%.
6. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure according to claim 5,
wherein said inner electrode is made of at least one or more kinds of
metals selected from Au, Pt, Rh, Pd or Ni, or alloys or compositions
thereof.
7. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure according to claim 6,
wherein said outer electrode is made of at least one or more kinds of
metals selected from Pd, Ag, Ni, Cu or Zn, or alloys or compositions
thereof.
8. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure according to claim 5
wherein said outer electrode is made of at least one or more kinds of
metals selected from Pd, Ag, Ni, Cu or Zn, or alloys or compositions
thereof.
9. A semiconductor-type laminated ceramic capacitor with a grain
boundary-structure comprising a plurality of inner electrodes on the
surfaces of the grain boundary insulated, semiconductor type ceramic
sheets, the terminal of each of said inner electrodes being extended to
one edge of the corresponding ceramic sheet and said ceramic sheets being
laminated so that said terminals of said inner electrodes come to the
corresponding opposite edges of said ceramic sheets alternatively one by
one; and outer electrodes electrically connected to said terminals of
inner electrodes at opposite edges of each of said grain boundary
insulated, semiconductor type ceramic sheets, wherein said ceramic sheets
comprise of a material of the composition of Sr.sub.(1-x) Ca.sub.x
TiO.sub.3 containing excess Ti to make final molecular ratio of Ti to
Sr.sub.(1-x) Ca.sub.x in the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x
/Ti<1.00(where x is in the range of 0.001.ltoreq.x--0.2) ; at least one or
more kinds of the compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2
O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2
O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added to said
ceramic material to make their relative molar content in the range from
0.05 to 2.0%; Mn and Si are also included in said ceramic material to the
amount of their combined relative molar content, converting into MnO.sub.2
and SiO.sub.2 respectively, in the range of 0.2 to 5.0%; and Na.sub.2
SiO.sub.3 is further included in said ceramic material to make relative
molar content in the range of 0.05-2.0%.
10. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure comprising the steps
of calcinating starting material of mixed powder in air or in nitrogen
atmosphere after grinding, mixing and drying said mixed powder; forming
raw sheets by dispersing said calcinated powder in a solvent with organic
binder and molding said dispersed powder, said calcinated powder being
re-ground before dispersing and after calcinating; printing a pattern of
inner electrode paste on the surface of said raw sheets, terminals of said
inner electrodes being extended to each of the corresponding opposite
edges of said raw sheets alternatively one by one (wherein patterns of
inner electrodes are not printed on uppermost and lowermost parts of raw
sheets); calcinating laminated body in air, said laminated body being
formed by laminating and compressing said raw sheets on which surfaces
patterns of inner electrode paste have been printed; sintering said
laminated raw sheets in reducing atmosphere or in nitrogen atmosphere
after calcination; re-oxidizing in air after sintering; and covering said
edges of sintered ceramic sheets with outer electrode paste and baking
after re-oxidation, terminals of inner electrodes being exposed to said
edges, wherein: said starting material of mixed powder comprises of a
material of the composition of Sr.sub.(1-x) Ca.sub.x TiO.sub.3 containing
excess Ti to make final molecular ratio of Ti to Sr.sub.(1-x) Ca.sub.x in
the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00 (where x is in the
range of 0.001.ltoreq.x.ltoreq.0.2); at least one or more kinds of the
compounds of Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2
O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2
O.sub.3 and CeO.sub.2 are added to said starting material to make their
relative molar content in the range from 0.05 to 2.0%; Mn and Si are also
included in said starting material to the amount of their combined
relative molar content, converting into MnO.sub.2 and SiO.sub.2
respectively, in the range of 0.2 to 5.0%; and Na.sub.2 SiO.sub.3 is
further included in said ceramic material to make relative molar content
in the range of 0.05-2.0%.
11. A semiconductor-type laminated ceramic capacitor with a grain
boundary-insulated structure comprising a plurality of inner electrodes on
the surfaces of the grain boundary insulated, semiconductor type ceramic
sheets, the terminal of each of said inner electrodes being extended to
one edge of the corresponding ceramic sheet and said ceramic sheets being
laminated so that said terminals of said inner electrodes come to the
corresponding opposite edges of said ceramic sheets alternatively one by
one; and outer electrodes electrically connected to said terminals of
inner electrodes at opposite edges of each of said grain boundary
insulated, semiconductor type ceramic sheets, wherein said ceramic sheets
comprise of a material of the composition of Sr.sub.(1-x) Ca.sub.x
TiO.sub.3 containing excess Ti to make final molecular ratio of Ti to
Sr.sub.(1-x) Ca.sub.x in the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x
/Ti<1.00 (where x is in the range of 0.001.ltoreq.x.ltoreq.0.2); at least
one or more kinds of the compounds selected from Nb.sub.2 O.sub.5,
Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3,
Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added
to said ceramic material to make their relative molar content in the range
from 0.05 to 2.0%; Mn and Si are also included in said ceramic material to
the amount of their combined relative molar content, converting into
MnO.sub.2 and SiO.sub.2 respectively, in the range of 0.2 to 5.0%; and
Al.sub.2 O.sub.3 is further included in said ceramic material to make
relative molar content in the range of 0.01-2.0%.
12. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure comprising the steps
of calcinating starting material of mixed powder in air or in nitrogen
atmosphere after grinding, mixing and drying said mixed powder; forming a
raw sheets by dispersing said calcinated powder in a solvent with organic
binder and molding said dispersed powder, said calcinated powder being
re-ground before dispersing and after calcinating; printing a pattern of
inner electrode paste on the surfaces of said raw sheets, terminals of
said inner electrodes being extended to each of the corresponding opposite
edges of said raw sheets alternatively one by one (wherein patterns of
inner electrodes are not printed on uppermost and lowermost parts of raw
sheets); calcinating laminated body in air, said laminated body being
formed by laminating and compressing said raw sheets on which surfaces
patterns of inner electrode paste has been printed; sintering said
laminated raw sheets in reducing atmosphere or in nitrogen atmosphere
after calcination; re-oxidizing in air after sintering; and covering said
edges of sintered ceramic sheets with outer electrode paste and baking
after reoxidation, terminals of inner electrodes being exposed to said
edges, wherein: said starting material of mixed powder comprises of a
material of the composition of Sr.sub.(1-x) Ca.sub.x TiO.sub.b 3
containing excess Ti to make final molecular ratio of Ti to Sr.sub.(1-x)
Ca.sub.x in the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00 (where
x is in the range of 0.001.ltoreq.x.ltoreq.0.2); at least one or more
kinds of the compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5,
V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2 O.sub.3,
Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added to said starting
material to make their relative molar content in the range from 0.05 to
2.0%; Mn and Si are also included in said starting material to the amount
of their combined relative molar content, converting into MnO.sub.2 and
SiO.sub.2 respectively, in the range of 0.2 to 5.0%; and Al.sub.2 O.sub.3
is further included in said ceramic material to make relative molar
content in the range of 0.01-2.0%.
13. A semiconductor-type laminated ceramic capacitor with a grain
boundary-insulated structure comprising a plurality of inner electrodes on
the surfaces of the grain boundary insulated, semiconductor type ceramic
sheets, the terminal of each of said inner electrodes being extended to
one edge of the corresponding ceramic sheet and said ceramic sheets being
laminated so that said terminals of said inner electrodes come to the
corresponding opposite edges of said ceramic sheets alternatively one by
one; and outer electrodes electrically connected to said terminals of
inner electrodes at opposite edges of each of said grain boundary
insulated, semiconductor type ceramic sheets, wherein said ceramic sheets
comprise of a material of the composition of Sr.sub.(1-x) Ca.sub.x
TiO.sub.3 containing excess Ti to make final molecular ratio of Ti to
Sr.sub.(1-x) Ca.sub.x in the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x
/Ti<1.00 (where x is in the range of 0.001.ltoreq.x.ltoreq.0.2); at least
one or more kinds of the compounds selected from Nb.sub.2 O.sub.5,
Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub. 2 O.sub.3,
Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added
to said ceramic material to make their relative molar content in the range
from 0.05 to 2.0%; Mn and Si are also included in said ceramic material to
the amount of their combined relative molar content, converting into
MnO.sub.2 and SiO.sub.2 respectively, in the range of 0.2 to 5.0%; and
NaAlO.sub.2 is further included in said ceramic material to make relative
molar content in the range of 0.05-4.0%.
14. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure comprising the steps
of calcinating starting material of mixed powder in air or in nitrogen
atmosphere after grinding, mixing and drying said mixed powder; forming
raw sheets by dispersing said calcinated powder in a solvent with organic
binder and molding said dispersed powder, said calcinated powder being
re-ground before dispersing and after calcinating; printing a pattern of
inner electrode paste on the surfaces of said raw sheets, terminals of
said inner electrodes being extended to each of the corresponding opposite
edges of said raw sheet alternatively one by one (wherein patterns of
inner electrodes are not printed on uppermost and lowermost parts of raw
sheets); calcinating laminated body in air, said laminated body being
formed by laminating and compressing said raw sheets on which surface
patterns of inner electrode paste have been printed; sintering said
laminated raw sheets in reducing atmosphere or in nitrogen atmosphere
after calcination; re-oxidizing in air after sintering; and covering said
edges of sintered ceramic sheets with outer electrode paste and baking
after re-oxidation, terminals of inner electrodes being exposed to said
edges, wherein: said starting material of mixed powder comprises of a
material of the composition of Sr.sub.(1-x) Ca.sub.x TiO.sub.3 containing
excess Ti to make final molecular ratio of Ti to Sr.sub.(1-x) Ca.sub.x in
the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00 (where x is in the
range of 0.001.ltoreq.x.ltoreq.0.2); at least one or more kinds of the
compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2
O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2 O.sub.3, Y.sub.2
O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added to said starting material
to make their relative molar content in the range from 0.05 to 2.0%; Mn
and Si are also included in said starting material to the amount of their
combined relative molar content, converting into MnO.sub.2 and SiO.sub.2
respectively, in the range of 0.2 to 5.0%; and NaAlO.sub.2 is further
included in said ceramic material to make relative molar content in the
range of 0.05-4.0%.
15. A grain boundary insulated, semiconductor type laminated ceramic
capacitor comprising a plurality of inner electrodes on the surfaces of
the grain boundary insulated, semiconductor type ceramic sheets, the
terminal of each of said inner electrodes being extended to one edge of
the corresponding ceramic sheet and said ceramic sheets being laminated so
that said terminals of said inner electrodes come to the corresponding
opposite edges of said ceramic sheets alternatively one by one; and outer
electrodes electrically connected to said terminals of inner electrodes at
opposite edges of each of said grain boundary insulated, semiconductor
type ceramic sheets, wherein: said ceramic sheets comprise of a material
of the composition of Sr.sub.(1-x) Ca.sub.x TiO.sub.3 containing excess Ti
to make final molecular ratio of Ti to Sr.sub.(1-x) Ca.sub.x in the range
of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00(where x is in the range of
0.001.ltoreq.x.ltoreq.0.2); at least one or more kinds of the compounds
selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2
O.sub.5, Dy.sub.2 O.sub. 3, Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2
O.sub.3 or CeO.sub.2 are added to said ceramic material to make their
relative molar content in the range from 0.05 to 2.0%; Mn and Si are also
included in said ceramic material to the amount of their combined relative
molar content, converting into MnO.sub.2 and SiO.sub.2 respectively, in
the range of 0.2 to 5.0%; and Li.sub.2 SiO.sub.3 is further included in
said ceramic material to make relative molar content in the range of
0.05-2.0%.
16. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-structure comprising the steps of:
calcinating starting material of mixed powder in air or in nitrogen
atmosphere after grinding, mixing and drying said mixed powder; forming a
raw sheets by dispersing said calcinated powder in a solvent with organic
binder and molding said dispersed powder, said calcinated powder being
re-ground before dispersing and after calcinating; printing a pattern of
inner electrode paste on the surface of said raw sheets, terminals of said
inner electrodes being extended to each of the corresponding opposite
edges of said raw sheets alternatively one by one (wherein patterns of
inner electrodes are not printed on uppermost and lowermost parts of raw
sheets); calcinating laminated body in air, said laminated body being
formed by laminating and compressing said raw sheets on which surfaces
patterns of inner electrode paste has been printed; sintering said
laminated raw sheets in reducing atmosphere or in nitrogen atmosphere
after calcination; re-oxidizing in air after sintering; and covering said
edges of sintered ceramic sheets with outer electrode paste and baking
after reoxidation, terminals of inner electrodes being exposed to said
edges, wherein: said starting material of mixed powder comprises of a
material of the composition of Sr.sub.(1-x) Ca.sub.x TiO.sub.3 containing
excess Ti to make final molecular ratio of Ti to Sr.sub.(1-x) Ca.sub.x in
the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00 (where x is in the
range of 0.001.ltoreq.x.ltoreq.0.2); at least one or more kinds of the
compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2
O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2 O.sub.3, Y.sub.2
O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added to said starting material
to make their relative molar content in the range from 0.05 to 2.0%; Mn
and Si are also included in said starting material to the amount of their
combined relative molar content, converting into MnO.sub.2 and SiO.sub.2
respectively, in the range of 0.2 to 5.0%; and Li.sub.2 SiO.sub.3 is
further included in said ceramic material to make relative molar content
in the range of 0.05-2.0%.
17. A semiconductor-type laminated ceramic capacitor with a grain
boundary-insulated structure comprising a plurality of inner electrodes on
the surfaces of the grain boundary insulated, semiconductor type ceramic
sheets, the terminal of each of said inner electrodes being extended to
one edge of the corresponding ceramic sheet and said ceramic sheets being
laminated so that said terminals of said inner electrodes come to the
corresponding opposite edges of said ceramic sheets alternatively one by
one; and outer electrodes electrically connected to said terminals of
inner electrodes at opposite edges of each of said insulated grain
boundary, semiconductor type ceramic sheets, wherein: said ceramic sheets
comprise of a material of the composition of Sr.sub.(1-x) Ca.sub.x
TiO.sub.3 containing excess Ti to make final molecular ratio of Ti to
Sr.sub.(1-x) Ca.sub.x in the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x
/Ti<1.00 (where x is in the range of 0.001.ltoreq.x.ltoreq.0.2); at least
one or more kinds of the compounds selected from Nb.sub.2 O.sub.5,
Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub. 2 O.sub.3,
Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added
to said ceramic material to make their relative molar content in the range
from 0.05 to 2.0%; Mn and Si are also included in said ceramic material to
the amount of their combined relative molar content, converting into
MnO.sub.2 and SiO.sub.2 respectively, in the range of 0.2 to 5 5.0%; and
LiAlO.sub.2 is further included in said ceramic material to make relative
molar content in the range of 0.05-4.0%.
18. A method for manufacturing a semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure comprising the steps
of: calcinating starting material of mixed powder in air or in nitrogen
atmosphere after grinding, mixing and drying said mixed powder; forming
raw sheets by dispersing said calcinated powder in a solvent with organic
binder and molding said dispersed powder, said calcinated powder being
re-ground before dispersing and after calcinating; printing a pattern of
inner electrode paste on the surface of said raw sheets, terminals of said
inner electrodes being extended to each of the corresponding opposite
edges of said raw sheets alternatively one by one (wherein patterns of
inner electrodes are not printed on uppermost and lowermost parts of raw
sheets); calcinating laminated body in air, said laminated body being
formed by laminating and compressing said raw sheets on which surfaces
patterns of inner electrode paste has been printed; sintering said
laminated raw sheets in reducing atmosphere or in nitrogen atmosphere
after calcination; re-oxidizing in air after sintering; and covering said
edges of sintered ceramic sheets with outer electrode paste and baking
after reoxidation, terminals of inner electrodes being exposed to said
edges, wherein: said starting material of mixed powder comprises of a
material of the composition of Sr.sub.(1-x) Ca.sub.x TiO.sub.3 containing
excess Ti to make final molecular ratio of Ti to Sr.sub.(1-x) Ca.sub.x in
the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00 (where x is in the
range of compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5,
V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2 O.sub.3,
Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added to said starting
material to make their relative molar content in the range from 0.05 to
2.0%; Mn and Si are also included in said starting material to the amount
of their combined relative molar content, converting into MnO.sub.2 and
SiO.sub.2 respectively, in the range of 0.2 to 5.0%; and LiAlO.sub.2 is
further included in said ceramic material to make relative molar content
in the range of 0.05-4.0%.
19. A semiconductor-type laminated ceramic capacitor with a grain
boundary-insulated structure comprising a plurality of inner electrodes on
the surfaces of the grain boundary insulated, semiconductor type ceramic
sheets, the terminal of each of said inner electrodes being extended to
one edge of the corresponding ceramic sheet and said ceramic sheets being
laminated so that said terminals of said inner electrodes come to the
corresponding opposite edges of said ceramic sheets alternatively one by
one; and outer electrodes electrically connected to said terminals of
inner electrodes at opposite edges of each of said grain boundary
insulated, semiconductor type ceramic sheets, wherein: said ceramic sheets
comprise of a material of the composition of Sr.sub.(1-x) Ca.sub.x
TiO.sub.3 containing excess Ti to make final molecular ratio of Ti to
Sr.sub.(1-x) Ca.sub.x in the range of 0.95.ltoreq.Sr(1-x)Ca.sub.x /Ti<1.00
(where x is in the range of 0.001.ltoreq.x.ltoreq.0.2); at least one or
more kinds of the compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2
O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2
O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added to said
ceramic material to make their relative molar content in the range from
0.05 to 2.0%; Mn and Si are also included in said ceramic material to the
amount of their combined relative molar content, converting into MnO.sub.2
and SiO.sub.2 respectively, in the range of 0.2 to 5.0%; and Na SiO.sub.3
and Al.sub.2 O.sub.3 are further included in said ceramic material to make
their relative molar contents in the range of 0.05-2.0% and 0.05-2.0%,
respectively.
20. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure comprising the steps
of: calcinating starting material of mixed powder in air or in nitrogen
atmosphere after grinding, mixing and drying said mixed powder; forming
raw sheets by dispersing said calcinated powder in a solvent with organic
binder and molding said dispersed powder, said calcinated powder being
re-ground before dispersing and after calcinating; printing a pattern of
inner electrode paste on the surface of said raw sheets, terminals of said
inner electrodes being extended to each of the corresponding opposite
edges of said raw sheets alternatively one by one (wherein patterns of
inner electrodes are not printed on uppermost and lowermost parts of raw
sheets); calcinating laminated body in air, said laminated body being
formed by laminating and compressing said raw sheets on which surfaces
patterns of inner electrode paste has been printed; sintering said
laminated raw sheets in a reducing atmosphere or in a nitrogen atmosphere
after calcination; re-oxidizing in air after sintering; and covering said
edges of sintered ceramic sheets with outer electrode paste and baking
after re-oxidation, terminals of inner electrodes being exposed to said
edges, wherein: said starting material of mixed powder comprises of a
material of the composition of Sr(1-x)Ca.sub.x TiO.sub.3 containing excess
Ti to make final molecular ratio of Ti to Sr.sub.(1-x) Ca.sub.x in the
range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00 (where x is in the
range of 0.001.ltoreq.x.ltoreq.0.2); at least one or more kinds of the
compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2
O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2 O , Y.sub.2
O.sub.3,La.sub.2 O.sub.3 or CeO.sub.2 are added to said starting material
to make their relative molar content in the range from 0.05 to 2.0%; Mn
and Si are also included in said starting material to the amount of their
combined relative molar content, converting into MnO.sub.2 and SiO.sub.2
respectively, in the range of 0.2 to 5.0%; and Na.sub.2 SiO.sub.3 and
Al.sub.2 O.sub.3 are further included in said ceramic material to make
their relative molar contents in the range of 0.05-2.0% and 0.05-2.0%,
respectively.
21. A semiconductor-type laminated ceramic capacitor with a grain
boundary-insulated structure comprising a plurality of inner electrodes on
the surfaces of the grain boundary insulated, semiconductor type ceramic
sheets, the terminal of each of said inner electrodes being extended to
one edge of the corresponding ceramic sheet and said ceramic sheets being
laminated so that said terminals of said inner electrodes come to the
corresponding opposite edges of said ceramic sheets alternatively one by
one; and outer electrodes electrically connected to said terminals of
inner electrodes at opposite edges of each of said grain boundary
insulated, semiconductor type ceramic sheets, wherein: said ceramic sheets
comprise of a material of the composition of Sr.sub.(1-x) Ca.sub.x
TiO.sub.3 containing excess Ti to make final molecular ratio of Ti to
Sr.sub.(1-x) Ca.sub.x in the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x
/Ti<1.00 (where x is in the range of 0.001.ltoreq.x.ltoreq.0.2); at least
one or more kinds of the compounds selected from Nb.sub.2 O.sub.5,
Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3,
Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3 or CeO.sub.2 are added
to said ceramic material to make their relative molar content in the range
from 0.05 to 2.0%; Mn and Si are also included in said ceramic material to
the amount of their combined relative molar content, converting into
MnO.sub.2 and SiO.sub.2 respectively, in the range of 0.2 to 5.0%; and
Li.sub.2 SiO.sub.3 and Al.sub.2 O.sub.3 are further included in said
ceramic material to make their relative molar contents in the range of
0.05-2.0% and 0.05-2.0%, respectively.
22. A method for manufacturing semiconductor-type laminated ceramic
capacitor with a grain boundary-insulated structure comprising the steps
of: calcinating starting material of mixed powder in air or in nitrogen
atmosphere after grinding, mixing and drying said mixed powder; forming
raw sheets by dispersing said calcinated powder in a solvent with organic
binder and molding said dispersed powder, said calcinated powder being
re-ground before dispersing and after calcinating; printing a pattern of
inner electrode paste on the surface of said raw sheets, terminals of said
inner electrodes being extended to each of the corresponding opposite
edges of said raw sheets alternatively one by one (wherein patterns of
inner electrodes are not printed on uppermost and lowermost parts of raw
sheets); calcinating laminated body in air, said laminated body being
formed by laminating and compressing said raw sheets on which surfaces
patterns of inner electrode paste has been printed; sintering said
laminated raw sheets in reducing atmosphere or in nitrogen atmosphere
after calcination; re-oxidizing in air after sintering; and covering said
edges of sintered ceramic sheets with outer electrode paste and baking
after re-oxidation, terminals of inner electrodes being exposed to said
edges, wherein: said starting material of mixed powder comprises of a
material of the composition of Sr.sub.(1-x) Ca.sub.x TiO.sub.3 containing
excess Ti to make final molecular ratio of Ti to Sr.sub.(1-x) Ca.sub.x in
the range of 0.95.ltoreq.Sr.sub.(1-x) Ca.sub.x /Ti<1.00 (where x is in the
range of 0.001.ltoreq.x.ltoreq.0.2); at least one or more kinds of the
compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2
O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.3, Nd.sub.2 O.sub.3, Y.sub.2
O.sub. 3, La.sub.2 O.sub.3 or CeO.sub.2 are added to said starting
material to make their relative molar content in the range from 0.05 to
2.0%; Mn and Si are also included in said starting material to the amount
of their combined relative molar content, converting into MnO.sub.2 and
SiO.sub.2 respectively, in the range of 0.2 to 5.0%; and Li.sub.2
SiO.sub.3 and Al.sub.2 O.sub.3 are further included in said ceramic
material to make their relative molar contents in the range of 0.05-2.0%
and 0.05-2.0%, respectively. |
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