US5763305A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming a semiconductor memory device with a capacitor
Assignee: United Microelectronics Corp
•
Filing: 1997-01-16
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Granted: 1998-06-09
•
Expires: 2017-01-16
Abstract
Abstract A method of fabricating a semiconductor memory device having a capacitor. First, a first insulating layer is formed on a substrate to cover the transistor. Next, a second insulating layer and a first conductive layer are formed in order. The first conductive layer only covers a portion of the second insulating layer to form a branch-like conductive layer. Then, a third insulating layer is formed. An opening is next formed. A second conductive layer is filled into the opening and therefore electrically connected to the source/drain region of the transistor to form a trunk-like conductive layer. Next, the second and the third insulating layers are removed. After a dielectric film is formed on the exposed surfaces of the first and second conductive layers, a third conductive layer is formed on the dielectric film to form an opposed electrode.
Inventors
- 👤 Fang-Ching Chao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:55
CPC Classifications
H; H10; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/033; H10B12/30; H10B12/31; H10B12/318; Y; Y10; Y10S; Y10S148/00; Y10S148/014
Claims Analysis
Total Claims: 60
Claim 1
Independent Claim
257 words
A method of forming a storage electrode of a storage capacitor of a semiconductor memory device, the semiconductor memory device further comprising a substrate, and a transfer transistor formed on the substrate and having a source/drain region, the storage capacitor being electrically connected to the source/drain region of the transfer transistor, the method comprising: a. forming a first insulating layer over the transfer transistor; b. forming a first conductive layer over the first insulating layer and penetrating at least the first insulating layer, and being electrically connected to the source/drain region of the transfer transistor; c. forming a second insulating layer on the first conductive layer, the second insulating layer having a knoll positioned substantially over the source/drain region; d. forming a second conductive layer on the second insulating layer, the second conductive layer covering at least the knoll of the second insulating layer; e. forming a third insulating layer over at least the second conductive layer; f. forming an opening through the third insulating layer, the second conductive layer and the second insulating layer so that a portion of the first conductive layer is exposed; g. forming a third conductive layer in the opening; h. patterning the first conductive layer so that the first and third conductive layers form a trunk-like conductive layer, and the second conductive layer forms a branch-like conductive layer; the storage electrode including the trunk-like and branch-like conductive layers; and i. removing the second and third insulating layers to expose at least some surfaces of the first, second and third conductive layers.
Claim 2
Independent Claim
257 words
A method of forming a storage electrode of a storage capacitor of a semiconductor memory device, the semiconductor memory device further comprising a substrate, and a transfer transistor formed on the substrate and having a source/drain region, the storage capacitor being electrically connected to the source/drain region of the transfer transistor, the method comprising: a. forming a first insulating layer over the transfer transistor; b. forming a first conductive layer over the first insulating layer and penetrating at least the first insulating layer, and being electrically connected to the source/drain region of the transfer transistor; c. forming a second insulating layer on the first conductive layer, the second insulating layer having a knoll positioned substantially over the source/drain region; d. forming a second conductive layer on the second insulating layer, the second conductive layer covering at least the knoll of the second insulating layer; e. forming a third insulating layer over at least the second conductive layer; f. forming an opening through the third insulating layer, the second conductive layer and the second insulating layer so that a portion of the first conductive layer is exposed; g. forming a third conductive layer in the opening; h. patterning the first conductive layer so that the first and third conductive layers form a trunk-like conductive layer, and the second conductive layer forms a branch-like conductive layer; the storage electrode including the trunk-like and branch-like conductive layers; and i. removing the second and third insulating layers to expose at least some surfaces of the first, second and third conductive layers.
Claim 3
Dependent Claim
50 words
A method as claimed in claim 1, further comprising the steps of forming a dielectric layer on the exposed surfaces of the first, second, and third conductive layers, and forming a fourth conductive layer on a surface of the dielectric layer to form an opposed electrode of the storage capacitor.
Claim 4
Dependent Claim
59 words
A method as claimed in claim 1, wherein the first conductive layer forms a lower trunk-like conductive layer, and the third conductive layer forms an upper trunk-like conductive layer, the lower trunk-like conductive layer being electrically connected to the source/drain region, and the upper trunk-like conductive layer contacting the lower trunk-like conductive layer and extending away from the substrate.
Claim 5
Dependent Claim
18 words
A method as claimed in claim 3, wherein the lower trunk-like conductive layer is T-shaped in cross section.
Claim 6
Dependent Claim
20 words
A method as claimed in claim 3, wherein the upper trunk-like conductive layer is substantially formed as a solid cylinder.
Claim 7
Dependent Claim
57 words
A method as claimed in claim 1, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the third insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the third insulating layer by etching back to form the third conductive layer in the opening.
Claim 8
Dependent Claim
21 words
A method as claimed in claim 1, wherein in step (g), the third conductive layer is an epitaxially grown polysilicon layer.
Claim 9
Dependent Claim
58 words
A method as claimed in claim 1, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the third insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the third insulating layer by chemical mechanical polishing to form the third conductive layer in the opening.
Claim 10
Dependent Claim
45 words
A method as claimed in claim 1, further comprising the step of forming an etching protection layer on the first insulating layer which is performed after step (a) and before step (b), wherein in step (b), the first conductive layer penetrates the etching protection layer.
Claim 11
Dependent Claim
83 words
A method as claimed in claim 1, further comprising the steps of forming, after step (e), a fourth conductive layer on the third insulating layer and over at least the knoll of the second insulating layer; and forming, before step (f), a fourth insulating layer on the fourth conductive layer, wherein the second and fourth conductive layers form substantially parallel branch-like conductive layers, and wherein the opening in step (f) is additionally formed through the fourth insulating layer and the fourth conductive layer.
Claim 12
Dependent Claim
28 words
A method as claimed in claim 10, further comprising the step of forming a dielectric layer on exposed surfaces of the first, second third and fourth conductive layers.
Claim 13
Dependent Claim
59 words
A method as claimed in claim 10, wherein the first conductive layer forms a lower trunk-like conductive layer, and the third conductive layer forms an upper trunk-like conductive layer, the lower trunk-like conductive layer being electrically connected to the source/drain region, and the upper trunk-like conductive layer contacting the lower trunk-like conductive layer and extending away from the substrate.
Claim 14
Dependent Claim
18 words
A method as claimed in claim 12, wherein the lower trunk-like conductive layer is T-shaped in cross section.
Claim 15
Dependent Claim
20 words
A method as claimed in claim 12, wherein the upper trunk-like conductive layer is substantially formed as a solid cylinder.
Claim 16
Dependent Claim
57 words
A method as claimed in claim 10, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the fourth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fourth insulating layer by etching back to form the third conductive layer in the opening.
Claim 17
Dependent Claim
21 words
A method as claimed in claim 10, wherein in step (g), the third conductive layer is an epitaxially grown polysilicon layer.
Claim 18
Dependent Claim
58 words
A method as claimed in claim 10, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the fourth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fourth insulating layer by chemical mechanical polishing to form the third conductive layer in the opening.
Claim 19
Dependent Claim
124 words
A method as claimed in claim 10, further comprising the steps of forming, before step (f), a fifth conductive layer on the fourth insulating layer, wherein an upper surface of the fourth insulating layer is substantially parallel to an upper surface of the substrate; and forming, before step (f), a fifth insulating layer on the fifth conductive layer, wherein in step (f), the opening is additionally formed through the fifth conductive layer and the fifth insulating layer, and wherein step (h) further includes the substep of patterning the fifth conductive layer to form the fifth conductive layer as a branch-like conductive layer, and step (i) further includes the substep of removing the fifth insulating layer to expose a surface of the fifth conductive layer.
Claim 20
Dependent Claim
29 words
A method as claimed in claim 18, further comprising the step of forming a dielectric layer on exposed surfaces of the first, second, third, fourth and fifth conductive layers.
Claim 21
Dependent Claim
57 words
A method as claimed in claim 18, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the fifth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fifth insulating layer by etching back to form the third conductive layer in the opening.
Claim 22
Dependent Claim
21 words
A method as claimed in claim 18 wherein in step (g), the third conductive layer is an epitaxially grown polysilicon layer.
Claim 23
Dependent Claim
58 words
A method as claimed in claim 19, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the fifth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fifth insulating layer by chemical mechanical polishing to form the third conductive layer in the opening.
Claim 24
Dependent Claim
129 words
A method as claimed in claim 10, further comprising the steps of: forming, after step (e), a fourth conductive layer on the third insulating layer, wherein in step (e), an upper surface of the third insulating layer is substantially parallel to an upper surface of the substrate; and forming, before step (f), a fourth insulating layer on the fourth conductive layer wherein step (f) further includes the substep of forming the opening additionally through the fourth conductive layer and the fourth insulating layer; step (h) further includes the substep of patterning the fourth conductive layer so that the fourth conductive layer forms an additional branch-like conductive layer; and step (i) further includes the substep of removing the fourth insulating layer to expose a surface of the fourth conductive layer.
Claim 25
Dependent Claim
28 words
A method as claimed in claim 23, further comprising the step of forming a dielectric layer on exposed surfaces of the first, second, third and fourth conductive layers.
Claim 26
Dependent Claim
57 words
A method as claimed in claim 23, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the fourth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fourth insulating layer by etching back to form the third conductive layer in the opening.
Claim 27
Dependent Claim
21 words
A method as claimed in claim 23, wherein in step (g), the third conductive layer is an epitaxially grown polysilicon layer.
Claim 28
Dependent Claim
58 words
A method as claimed in claim 23, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the fourth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fourth insulating layer by chemical mechanical polishing to form the third conductive layer in the opening.
Claim 29
Dependent Claim
71 words
A method as claimed in claim 1, further comprising the step of forming, after step (a) and before step (b), an etching protection layer on the first insulating layer, and a fourth insulating layer on the etching protection layer, wherein in step (b), the first conductive layer additionally penetrates the fourth insulating layer and the etching protection layer; and step (i) further includes the substep of removing the fourth insulating layer.
Claim 30
Dependent Claim
57 words
A method as claimed in claim 28, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the third insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the third insulating layer by etching back to form the third conductive layer in the opening.
Claim 31
Dependent Claim
21 words
A method as claimed in claim 28, wherein in step (g), the third conductive layer is an epitaxially grown polysilicon layer.
Claim 32
Dependent Claim
58 words
A method as claimed in claim 28, wherein step (g) includes the substeps of depositing, a polysilicon layer on an upper surface of the third insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the third insulating layer by chemical mechanical polishing to form the third conductive layer in the opening.
Claim 33
Dependent Claim
83 words
A method as claimed in claim 28 further comprising the steps of forming, after step (e), a fourth conductive layer on the third insulating layer and over at least the knoll of the second insulating layer; and forming, before step (f), a fifth insulating layer on the fourth conductive layer, wherein the second and fourth conductive layers form substantially parallel branch-like conductive layers, and wherein the opening in step (f) is additionally formed through the fifth insulating layer and the fourth conductive layer.
Claim 34
Dependent Claim
28 words
A method as claimed in claim 32, further comprising the step of forming a dielectric layer on exposed surfaces of the first, second, third and fourth conductive layers.
Claim 35
Dependent Claim
57 words
A method as claimed in claim 32, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the fifth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fifth insulating layer by etching back to form the third conductive layer in the opening.
Claim 36
Dependent Claim
21 words
A method as claimed in claim 32, wherein in step (g), the third conductive layer is an epitaxially grown polysilicon layer.
Claim 37
Dependent Claim
58 words
A method as claimed in claim 32, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the fifth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fifth insulating layer by chemical mechanical polishing to form the third conductive layer in the opening.
Claim 38
Dependent Claim
127 words
A method as claimed in claim 32, further comprising the steps of forming, after step (e), a fifth conductive layer on the fifth insulating layer, an upper surface of the fifth insulating layer being substantially parallel to an upper surface of the substrate; and forming, before step (f), a sixth insulating layer on the fifth conductive layer, wherein in step (f), the opening is additionally formed through the fifth conductive layer and the sixth insulating layer; and wherein step (h) further includes the substep of patterning the fifth conductive layer to form the fifth conductive layer as a branch-like conductive layer; and step (i) further includes the substep of removing the sixth and fifth insulating layers to expose a surface of the fourth and fifth conductive layers.
Claim 39
Dependent Claim
30 words
A method as claimed in claim 37, further comprising the step of forming a dielectric layer on the exposed surfaces of the first, second, third, fourth and fifth conductive layers.
Claim 40
Dependent Claim
56 words
A method as claimed in claim 37, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the sixth insulating layer and in the opening, and removing the polysilicon layer on the surface of the sixth insulating layer by etching back to form the third conductive layer in the opening.
Claim 41
Dependent Claim
21 words
A method as claimed in claim 37, wherein in step (g) the third conductive layer is an epitaxially grown polysilicon layer.
Claim 42
Dependent Claim
58 words
A method as claimed in claim 37, wherein step (g) includes the substeps of depositing a polysilicon layer on an upper surface of the sixth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the sixth insulation layer by chemical mechanical polishing to form the third conductive layer in the opening.
Claim 43
Independent Claim
233 words
A method of forming a storage electrode of a storage capacitor of a semiconductor memory device, the semiconductor memory device further comprising a substrate, and a transfer transistor formed on the substrate and having a source/drain region, the storage capacitor being electrically connected to the source/drain region of the transfer transistor, the method comprising: a. forming a first insulating layer over the transfer transistor; b. forming a second insulating layer over the first insulating layer, the second insulating layer having a knoll positioned substantially over the source/drain region; c. forming a first conductive layer on a portion of the second insulating layer and at least over the knoll of the second insulating layer; d. forming a third insulating layer over at least the first conductive layer and over the knoll; e. forming an opening through the third insulating layer, the first conductive layer, the second insulating layer and the first insulating layer so that the source/drain region is exposed; f. forming a second conductive layer in the opening so that the second conductive layer is electrically connected to the source/drain region; wherein the second conductive layer forms a trunk-like conductive layer; the first conductive layer forms a branch-like conductive layer; and the storage electrode includes the trunk-like and branch-like conductive layers; and g. removing the second and third insulating layers to expose at least some surfaces of the first and second conductive layers.
Claim 44
Independent Claim
233 words
A method of forming a storage electrode of a storage capacitor of a semiconductor memory device, the semiconductor memory device further comprising a substrate, and a transfer transistor formed on the substrate and having a source/drain region, the storage capacitor being electrically connected to the source/drain region of the transfer transistor, the method comprising: a. forming a first insulating layer over the transfer transistor; b. forming a second insulating layer over the first insulating layer, the second insulating layer having a knoll positioned substantially over the source/drain region; c. forming a first conductive layer on a portion of the second insulating layer and at least over the knoll of the second insulating layer; d. forming a third insulating layer over at least the first conductive layer and over the knoll; e. forming an opening through the third insulating layer, the first conductive layer, the second insulating layer and the first insulating layer so that the source/drain region is exposed; f. forming a second conductive layer in the opening so that the second conductive layer is electrically connected to the source/drain region; wherein the second conductive layer forms a trunk-like conductive layer; the first conductive layer forms a branch-like conductive layer; and the storage electrode includes the trunk-like and branch-like conductive layers; and g. removing the second and third insulating layers to expose at least some surfaces of the first and second conductive layers.
Claim 45
Dependent Claim
49 words
A method as claimed in claim 42, further comprising the steps of forming a dielectric layer on the exposed surfaces of the first and second conductive layers; and forming a third conductive layer on a surface of the dielectric layer to form an opposed electrode of the storage capacitor.
Claim 46
Dependent Claim
19 words
A method as claimed in claim 42, wherein the trunk-like conductive layer is substantially formed as a solid cylinder.
Claim 47
Dependent Claim
57 words
A method as claimed in claim 42, wherein step (f) includes the substeps of depositing a polysilicon layer on an upper surface of the third insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the third insulating layer by etching back to form the second conductive layer in the opening.
Claim 48
Dependent Claim
21 words
A method as claimed in claim 42, wherein in step (f), the second conductive layer is an epitaxially grown polysilicon layer.
Claim 49
Dependent Claim
58 words
A method as claimed in claim 42, wherein step (f) includes the substeps of depositing a polysilicon layer on an upper surface of the third insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the third insulting layer by chemical mechanical polishing to form the second conductive layer in the opening.
Claim 50
Dependent Claim
45 words
A method as claimed in claim 42, further comprising the step of forming an etching protection layer on the first insulating layer after step (a) and before step (b), wherein step (e) further includes the substep of forming the opening through the etching protection layer.
Claim 51
Dependent Claim
93 words
A method as claimed in claim 42, further comprising the steps of forming, after step (d) and before step (e) a third conductive layer over the third insulating layer and forming a fourth insulating layer over the third conductive layer, wherein the first and third conductive layers form substantially parallel branch-like conductive layers and wherein step (e) includes the substep of additionally forming the opening through the third conductive layer and the fourth insulating layer, and wherein a dielectric layer is formed on exposed surfaces of the first, second, and third conductive layers.
Claim 52
Dependent Claim
19 words
A method as claimed in claim 49, wherein the trunk-like conductive layer is substantially formed as a solid cylinder.
Claim 53
Dependent Claim
57 words
A method as claimed in claim 49, wherein step (f) includes the substeps of depositing a polysilicon layer on an upper surface of the fourth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fourth insulating layer by etching back to form the second conductive layer in the opening.
Claim 54
Dependent Claim
21 words
A method as claimed in claim 49, wherein in step (f), the second conductive layer is an epitaxially grown polysilicon layer.
Claim 55
Dependent Claim
58 words
A method as claimed in claim 49, wherein step (f) includes the substeps of depositing a polysilicon layer on an upper surface of the fourth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fourth insulating layer by chemical mechanical polishing to form the second conductive layer in the opening.
Claim 56
Dependent Claim
123 words
A method as claimed in claim 42, further comprising the steps of forming, after step (d), a third conductive layer on the third insulating layer, an upper surface of the third insulating layer being substantially parallel to an upper surface of the substrate; and forming, before step (e), a fourth insulating layer on the third conductive layer; wherein in step (e), the opening is additionally formed through the third conductive layer and the fourth insulating layer; and wherein step (f) further includes the step of patterning the third conductive layer so that the third conductive layer forms a branch-like conductive layer; and step (g) further includes the substep of removing the fourth insulating layer to expose a surface of the third conductive layer.
Claim 57
Dependent Claim
28 words
A method as claimed in claim 54, further comprising the step of forming a dielectric layer on the exposed surfaces of the first, second and third conductive layers.
Claim 58
Dependent Claim
57 words
A method as claimed in claim 54, wherein step (f) includes the substeps of depositing a polysilicon layer on an upper surface of the fourth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fourth insulating layer by etching back to form the second conductive layer in the opening.
Claim 59
Dependent Claim
21 words
A method as claimed in claim 54, wherein in step (f), the second conductive layer is an epitaxially grown polysilicon layer.
Claim 60
Dependent Claim
58 words
A method as claimed in claim 54, wherein step (f) includes the substep of depositing a polysilicon layer on an upper surface of the fourth insulating layer and in the opening, and removing the polysilicon layer on the upper surface of the fourth insulating layer by chemical mechanical polishing to form the second conductive layer in the opening.
References Cited (Backward Citations)
US5071783A
Cited
US5572053A
Cited
US5521419A
Cited
US5126810A
Cited
US5196365A
Cited
US5089869A
Cited
US5172201A
Cited
US5077688A
Cited
US5164337A
Cited
US5142639A
Cited
JPH0426156A
Cited
US5102820A
Cited
US5371701A
Cited
US5158905A
Cited
US5274258A
Cited
GB2252447A
Cited
US5206787A
Cited
EP0516031A1
Cited
JPH0521745A
Cited
US5266512A
Cited
US5155657A
Cited
US5478770A
Cited
JPH05251657A
Cited
US5338955A
Cited
US5399518A
Cited
US5478768A
Cited
US5561310A
Cited
US5389568A
Cited
US5453633A
Cited
US5354704A
Cited
US5482886A
Cited
US5543346A
Cited
US5460996A
Cited
US5443993A
Cited
US5508222A
Cited
US5561309A
Cited
US5595931A
Cited
US5550080A
Cited
US5438011A
Cited
US5523542A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-06-08 | 2001-12-08 | 2002-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-06-08 | 2005-12-08 | 2006-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-06-08 | 2009-12-08 | 2010-06-09 | $7700.00 | Window Closed / Lapsed |