US6469389B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contact plug
Assignee: Micron Technology Inc
•
Filing: 2000-05-09
•
Granted: 2002-10-22
•
Expires: 2020-05-09
Abstract
Abstract Within an integrated circuit, a contact plug with a height not extending above the level of the gate/wordline nitride is nonetheless provided with a relatively large contact area or landing pad, significantly larger than the source/drain region to which the contact plug is electrically connected. Methods for producing the inventive contact plug include (1) use of a nitride facet etch, either (a) during a nitride spacer formation etch or (b) during a BPSG etch; (2) using at least one of (a) an isotropic photoresist etch or partial descum to narrow BPSG spacers above the gate/wordline nitride, and (b) a nitride step etch to etch the shoulder area of the gate/wordline nitride exposed by a BPSG etch; and (3) polishing a BPSG layer down to the top of a gate/wordline nitride before any doped polysilicon plug fill, masking for BPSG etch and performing a BPSG etch, etching the photoresist layer through a partial descum, and etching the shoulder area of the gate/wordline nitride exposed thereby.
Inventors
- 👤 Werner Juengling
- 👤 Kirk Prall
- 👤 Gordon Haller
- 👤 David Keller
- 👤 Tyler Lowrey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:24
CPC Classifications
H; H10; H10B; H10B12/00; H10B12/30; H10B12/48; H10B12/485; H10D; H10D64/00; H10D64/01; H10D64/011; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/069; H10W20/40; Y; Y10; Y10S; Y10S438/00; Y10S438/978
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
122 words
An electrical device comprising: a semiconductor substrate having an active region therein; a contact plug having a bottom surface with a width on the active region and an opposite top surface with a width, wherein: the width of the bottom surface is less than the width of the top surface; and the contact plug has an external surface from the top surface to the bottom surface that is continuously in contact with a single dielectric material that terminates at the top surface of the contact plug, wherein the external surface has at least one extended region with a constant first slope and at least one extended region with a constant second slope, and the first slope is different from the second slope.
Claim 2
Dependent Claim
122 words
An electrical device comprising: a semiconductor substrate having an active region therein; a contact plug having a bottom surface with a width on the active region and an opposite top surface with a width, wherein: the width of the bottom surface is less than the width of the top surface; and the contact plug has an external surface from the top surface to the bottom surface that is continuously in contact with a single dielectric material that terminates at the top surface of the contact plug, wherein the external surface has at least one extended region with a constant first slope and at least one extended region with a constant second slope, and the first slope is different from the second slope.
Claim 3
Dependent Claim
21 words
The electrical device as defined in claim 1 , wherein the contact plug is composed of a single electrically conductive material.
Claim 4
Dependent Claim
23 words
The electrical device as defined in claim 1 , wherein the single dielectric material is a spacer for at least one gate stack.
Claim 5
Dependent Claim
25 words
The electrical device as defined in claim 3 , wherein the spacer is symmetrical about opposite sides of a gate electrode over which it extends.
Claim 6
Dependent Claim
32 words
The electrical device as defined in claim 1 , wherein the active region has a width that is not as wide as the width of the top surface of the contact plug.
Claim 7
Dependent Claim
27 words
The electrical device as defined in claim 1 , wherein a planar surface of the dielectric material is co-planar with the top surface of the contact plug.
Claim 8
Dependent Claim
141 words
The electrical device as defined in claim 1 , further comprising a plurality of said contact plugs each having a bottom surface with a width on an active region in the semiconductor substrate and an opposite top surface with a width, wherein: the width of the bottom surface of each said contact plug is less than the width of the top surface thereof; and at least one of said contact plugs has an external surface from the top surface thereof to the bottom surface thereof that is continuously in contact with a single dielectric material that terminates at the top surface of the contact plug, wherein the external surface has at least one extended region with a constant first slope and at least one extended region with a constant second slope, and the first slope is different from the second slope.
Claim 9
Dependent Claim
43 words
The electrical device as defined in claim 7 , wherein: the single dielectric material is a spacer upon a gate stack; each said spacer has opposite sides; and each opposite side of each spacer is in contact with one of said contact plugs.
Claim 10
Dependent Claim
21 words
The electrical device as defined in claim 8 , wherein each spacer is in contact with two of said contact plugs.
Claim 11
Dependent Claim
31 words
The electrical device as defined in claim 7 , wherein each said contact plug is separated from a pair of other contact plugs by a volume of said single dielectric material.
Claim 12
Dependent Claim
22 words
The electrical device as defined in claim 7 , wherein each said contact plug is composed of a single electrically conductive material.
Claim 13
Dependent Claim
31 words
The electrical device as defined in claim 7 , wherein the single dielectric material is a spacer for at least one gate stack that is adjacent to each said contact plug.
Claim 14
Dependent Claim
34 words
The electrical device as defined in claim 7 , wherein each said active region has a width that is not as wide as the width of the top surface of the contact plug thereon.
Claim 15
Dependent Claim
41 words
The electrical device as defined in claim 7 , wherein the single dielectric material in contact with each said contact plug terminates at a planar top surface that is co-planar with the top surface of the contact plug in contact therewith.
Claim 16
Dependent Claim
33 words
The electrical device as defined in claim 1 , wherein said single dielectric has a top end that terminates at said top surface of the contact plug, and said top end is faceted.
Claim 17
Dependent Claim
126 words
An electrical device comprising: a semiconductor substrate having an active region therein; a contact plug having a bottom surface with a width on the active region and an opposite top surface with a width, wherein: the width of the bottom surface is less than the width of the top surface; and the contact plug has an external surface from the top surface to the bottom surface; a pair of gate stacks each: being upon the semiconductor substrate; having a spacer composed of a single dielectric material that extends from the semiconductor substrate to terminate at the top surface of the contact plug, wherein each said spacer makes a continuous contact with the external surface of the contact plug from the top surface to the bottom surface.
Claim 18
Dependent Claim
126 words
An electrical device comprising: a semiconductor substrate having an active region therein; a contact plug having a bottom surface with a width on the active region and an opposite top surface with a width, wherein: the width of the bottom surface is less than the width of the top surface; and the contact plug has an external surface from the top surface to the bottom surface; a pair of gate stacks each: being upon the semiconductor substrate; having a spacer composed of a single dielectric material that extends from the semiconductor substrate to terminate at the top surface of the contact plug, wherein each said spacer makes a continuous contact with the external surface of the contact plug from the top surface to the bottom surface.
Claim 19
Dependent Claim
29 words
The electrical device as defined in claim 16 , wherein the contact plug is composed of a single electrically conductive material from the top surface to the bottom surface.
Claim 20
Dependent Claim
32 words
The electrical device as defined in claim 16 , wherein the active region has a width that is not as wide as the width of the top surface of the contact plug.
Claim 21
Dependent Claim
27 words
The electrical device as defined in claim 16 , wherein a planar surface of the dielectric material is co-planar with the top surface of the contact plug.
Claim 22
Dependent Claim
42 words
The electrical device as defined in claim 16 , wherein each said gate stack includes a gate electrode upon a gate oxide layer and a refractory metal silicide layer upon each said gate electrode that is in contact with the corresponding spacer.
Claim 23
Dependent Claim
18 words
The electrical device as defined in claim 16 , wherein the single dielectric material is composed of nitride.
Claim 24
Dependent Claim
26 words
The electrical device as defined in claim 16 , wherein each said spacer is symmetrical about opposite sides of a gate electrode over which it extends.
Claim 25
Dependent Claim
33 words
The electrical device as defined in claim 16 , wherein said dielectric material has a top end that terminates at said top surface of the contact plug and said top end is faceted.
Claim 26
Dependent Claim
43 words
The electrical device as defined in claim 16 , wherein each of said gate stacks has a bottom end on the semiconductor substrate and an opposite top end, and wherein the top end of at least one of said gate stacks is faceted.
Claim 27
Dependent Claim
171 words
An electrical device comprising: a semiconductor substrate having an active region therein; a contact plug having a bottom surface with a width on the active region and an opposite top surface with a width, wherein: the width of the bottom surface is less than the width of the top surface, and the contact plug has an external surface from the top surface to the bottom surface that is continuously in contact with a single dielectric material that terminates at the top surface of the contact plug, the dielectric material extending from a dielectric material base upon the semiconductor substrate adjacent to the bottom surface and terminating at the top surface, wherein the dielectric material reaches the top surface at a region that is displaced from the vertical position with respect to the dielectric material base, and the external surface has at least one extended region with a constant first slope and at least one extended region with a constant second slope, and the first slope is different from the second slope.
Claim 28
Dependent Claim
171 words
An electrical device comprising: a semiconductor substrate having an active region therein; a contact plug having a bottom surface with a width on the active region and an opposite top surface with a width, wherein: the width of the bottom surface is less than the width of the top surface, and the contact plug has an external surface from the top surface to the bottom surface that is continuously in contact with a single dielectric material that terminates at the top surface of the contact plug, the dielectric material extending from a dielectric material base upon the semiconductor substrate adjacent to the bottom surface and terminating at the top surface, wherein the dielectric material reaches the top surface at a region that is displaced from the vertical position with respect to the dielectric material base, and the external surface has at least one extended region with a constant first slope and at least one extended region with a constant second slope, and the first slope is different from the second slope.
Claim 29
Dependent Claim
29 words
The electrical device as defined in claim 25 , wherein the contact plug is composed of a single electrically conductive material from the top surface to the bottom surface.
Claim 30
Dependent Claim
23 words
The electrical device as defined in claim 25 , wherein the single dielectric material is a spacer for at least one gate stack.
Claim 31
Dependent Claim
32 words
The electrical device as defined in claim 25 , wherein the active region has a width that is not as wide as the width of the top surface of the contact plug.
Claim 32
Dependent Claim
27 words
The electrical device as defined in claim 25 , wherein a planar surface of the dielectric material is co-planar with the top surface of the contact plug.
Claim 33
Dependent Claim
34 words
The electrical device as defined in claim 25 , wherein said single dielectric material has a top end that terminates at said top surface of the contact plug, and said top end is faceted.
References Cited (Backward Citations)
US3996657A
Cited
US4784719A
Cited
US5304829A
Cited
US5014098A
Cited
US5236549A
Cited
US5234852A
Cited
US5116460A
Cited
US5517044A
Cited
US5420075A
Cited
US5340763A
Cited
US5705838A
Cited
US5500816A
Cited
US5378646A
Cited
US5675185A
Cited
US6060783A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2005-10-21 | 2006-04-22 | 2006-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-10-21 | 2010-04-22 | 2010-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-10-21 | 2014-04-22 | 2014-10-22 | $7700.00 | Window Closed / Lapsed |