US6008103A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming trench capacitors in an integrated circuit
Assignee: Qimonda AG
•
Filing: 1998-02-27
•
Granted: 1999-12-28
•
Expires: 2018-02-27
Abstract
Abstract A method for forming a trench capacitor in a substrate, including a buried plate of the trench capacitor, is disclosed. The method includes forming a trench within the substrate. The trench has a trench interior surface. The method further includes forming an oxide collar within the trench. The oxide collar covers a first portion of the trench interior surface, leaving a second portion of the trench interior surface uncovered with the oxide collar. There is also included doping the second portion of the trench interior surface with a first dopant using a plasma-enhanced doping process. The plasma-enhanced doping process being configured to cause the first dopant to diffuse into the second portion substantially without depositing an additional layer on the trench interior surface. Additionally, there is included driving the first dopant into the substrate using a high temperature process to form the buried plate.
Inventors
- 👤 Joachim Hoepfner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:09
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/01; H10D1/045; H10D1/047; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/038
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
117 words
A method fabricating a semiconductor device, the method comprising: forming a trench within a semiconductor body, said trench having a trench interior surface; forming an oxide collar within said trench, said oxide collar covering a first portion of said trench interior surface, leaving a second portion of said trench interior surface uncovered with said oxide collar; thereafter, doping said second portion of said trench interior surface with a first dopant using a plasma-enhanced doping process, said plasma-enhanced doping process being configured to cause said first dopant to diffuse into said second portion substantially without depositing an additional layer on said trench interior surface; and driving said first dopant into said semiconductor body using a high temperature process.
Claim 2
Independent Claim
117 words
A method fabricating a semiconductor device, the method comprising: forming a trench within a semiconductor body, said trench having a trench interior surface; forming an oxide collar within said trench, said oxide collar covering a first portion of said trench interior surface, leaving a second portion of said trench interior surface uncovered with said oxide collar; thereafter, doping said second portion of said trench interior surface with a first dopant using a plasma-enhanced doping process, said plasma-enhanced doping process being configured to cause said first dopant to diffuse into said second portion substantially without depositing an additional layer on said trench interior surface; and driving said first dopant into said semiconductor body using a high temperature process.
Claim 3
Dependent Claim
21 words
The method of claim 1 wherein said forming said oxide collar is accomplished using a local oxidation of silicon (LOCOS) process.
Claim 4
Dependent Claim
20 words
The method of claim 1 wherein said semiconductor body represents a p-type substrate, said first dopant represents an n-type dopant.
Claim 5
Dependent Claim
12 words
The method of claim 3 wherein said first dopant represents arsenic dopant.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein said semiconductor body represents an n-type substrate, said first dopant represents a p-type dopant.
Claim 7
Dependent Claim
18 words
The method of claim 1 wherein said plasma doping process comprises a plasma immersion ion implantation (PIII) process.
Claim 8
Dependent Claim
16 words
The method of claim 1 wherein said plasma doping process comprises a plasma doping (PLAD) process.
Claim 9
Dependent Claim
37 words
The method of claim 1 further comprising: forming a cap layer above said first dopant prior to said driving, said cap layer being configured to prevent said first dopant from contaminating a chamber employed during said driving.
Claim 10
Dependent Claim
31 words
The method of claim 1 wherein said trench represents a bottle-shaped trench, said bottle-shaped trench having a trench opening smaller than a cross-section of an interior region of said bottle-shaped trench.
Claim 11
Dependent Claim
22 words
The method of claim 9 wherein said bottle-shaped trench is employed in the fabrication of a dynamic random access memory (DRAM) circuit.
Claim 12
Dependent Claim
24 words
The method of claim 1 wherein the trench is formed as a trench for a trench capacitor, the trench capacitor including a buried plate.
Claim 13
Dependent Claim
36 words
The method of claim 1 wherein the trench is formed as a trench for a trench capacitor, the trench capacitor including a buried plate, said first dopant representing a dopant employed to form said buried plate.
Claim 14
Independent Claim
91 words
A method of fabricating a semiconductor device, said method comprising: forming a trench within a semiconductor body, said trench having a trench interior surface; forming an oxide collar within said trench, said oxide collar covering a first portion of said trench interior surface such that a second portion of said trench interior surface is exposed: and doping said second portion of said trench interior surface with a first dopant using a plasma-enhanced doping process said oxide collar preventing said first dopant from doping said first portion of said trench interior surface.
Claim 15
Independent Claim
91 words
A method of fabricating a semiconductor device, said method comprising: forming a trench within a semiconductor body, said trench having a trench interior surface; forming an oxide collar within said trench, said oxide collar covering a first portion of said trench interior surface such that a second portion of said trench interior surface is exposed: and doping said second portion of said trench interior surface with a first dopant using a plasma-enhanced doping process said oxide collar preventing said first dopant from doping said first portion of said trench interior surface.
Claim 16
Dependent Claim
26 words
The method of claim 13 wherein said plasma-enhanced doping process is one of a plasma immersion ion implantation (PIII) process and a plasma doping (PLAD) process.
Claim 17
Dependent Claim
33 words
The method of claim 13 wherein said oxide collar is employed as a mask to protect a substrate region adjacent said oxide collar from dopant penetration of said first dopant during said doping.
Claim 18
Dependent Claim
21 words
The process of claim 1 wherein said forming said oxide collar is accomplished using a local oxidation of silicon (LOCOS) process.
Claim 19
Dependent Claim
20 words
The process of claim 13 wherein said semiconductor body represents a p-type substrate, said first dopant represents an n-type dopant.
Claim 20
Dependent Claim
12 words
The process of claim 17 wherein said first dopant represents arsenic dopant.
Claim 21
Dependent Claim
20 words
The process of claim 13 wherein said semiconductor body represents an n-type substrate, said first dopant represents a p-type dopant.
Claim 22
Dependent Claim
37 words
The process of claim 13 further comprising: forming a cap layer above said first dopant prior to said driving, said cap layer being configured to prevent said first dopant from contaminating a chamber employed during said driving.
Claim 23
Dependent Claim
31 words
The method of claim 13 wherein said trench represents a bottle-shaped trench, said bottle-shaped trench having a trench opening smaller than a cross-section of an interior region of said bottle-shaped trench.
Claim 24
Dependent Claim
22 words
The method of claim 13 wherein said trench capacitor is employed in the fabrication of a dynamic random access memory (DRAM) circuit.
Claim 25
Dependent Claim
34 words
The method of claim 13 wherein said plasma-enhanced doping process is configured to cause said first dopant to diffuse into said second portion substantially without depositing an additional layer on said trench interior surface.
Claim 26
Independent Claim
155 words
A method for forming in a substrate a trench capacitor of a dynamic random access memory (DRAM) circuit, said trench capacitor including a buried plate, said method comprising: forming a trench within said substrate, said trench having a trench interior surface; forming an oxide collar within said trench, said oxide collar covering a second portion of said trench interior surface, leaving said first portion of said trench interior surface uncovered with said oxide collar; and doping at least said first portion of said trench interior surface with a first dopant using a plasma-enhanced doping process, said plasma-enhanced doping process is one of a plasma immersion ion implantation (PIII) process and a plasma doping (PLAD) process, said plasma-enhanced doping process being configured to cause said first dopant to diffuse into said first portion substantially without depositing an additional layer on said trench interior surface, said first dopant representing a dopant employed to form said buried plate.
Claim 27
Independent Claim
155 words
A method for forming in a substrate a trench capacitor of a dynamic random access memory (DRAM) circuit, said trench capacitor including a buried plate, said method comprising: forming a trench within said substrate, said trench having a trench interior surface; forming an oxide collar within said trench, said oxide collar covering a second portion of said trench interior surface, leaving said first portion of said trench interior surface uncovered with said oxide collar; and doping at least said first portion of said trench interior surface with a first dopant using a plasma-enhanced doping process, said plasma-enhanced doping process is one of a plasma immersion ion implantation (PIII) process and a plasma doping (PLAD) process, said plasma-enhanced doping process being configured to cause said first dopant to diffuse into said first portion substantially without depositing an additional layer on said trench interior surface, said first dopant representing a dopant employed to form said buried plate.
Claim 28
Dependent Claim
26 words
The method of claim 24 wherein said oxide collar is formed within said trench using a local oxidation of silicon (LOCOS) process prior to said doping.
Claim 29
Dependent Claim
33 words
The method of claim 24 further comprising employing said oxide collar as a mask to protect a substrate region adjacent said oxide collar from dopant penetration of said first dopant during said doping.
References Cited (Backward Citations)
US4861729A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-12-27 | 2003-06-28 | 2003-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-12-27 | 2007-06-28 | 2007-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-12-27 | 2011-06-28 | 2011-12-28 | $7700.00 | Window Closed / Lapsed |