US5229309A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing semiconductor device using a ferroelectric film over a source region
Assignee: Ramtron International Corp
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Filing: 1991-05-31
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Granted: 1993-07-20
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Expires: 2011-05-31
Abstract
Abstract A method for manufacturing a memory integrating a ferroelectric film, having properties such as excellent information rewriting times, breakdown voltage and leak current and the like, by forming a lower electrode sandwiching a ferroelectric material on a high concentration diffusion layer, such as source and drain regions, formed on a semiconductor substrate, and forming a polysilicon film between the electrode and the high concentration diffusion layer. A semiconductor device formed by the method of the present invention is also disclosed.
Inventors
- 👤 Koji Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:05
CPC Classifications
H; H10; H10B; H10B53/00; H10D; H10D1/00; H10D1/60; H10D1/68; H10D1/682
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
147 words
A method for forming a semiconductor device comprising the steps of: forming a source region and a drain region located in a substrate with a gate electrode over said substrate and between said source region and said drain region; establishing an insulating layer over said substrate and around said gate electrode; establishing a contact hole in said insulating layer to said source region; establishing a polysilicon film located directly over and in direct contact with the source region in said contact hole, the polysilicon film also being located over said insulating layer; establishing a lower electrode over said polysilicon film; establishing a ferroelectric film over said lower electrode; etching said lower electrode and said ferroelectric film; etching said polysilicon film so that said polysilicon film is in said contact hole and over a portion of said insulating layer; and establishing an upper electrode over said ferroelectric film.
Claim 2
Independent Claim
147 words
A method for forming a semiconductor device comprising the steps of: forming a source region and a drain region located in a substrate with a gate electrode over said substrate and between said source region and said drain region; establishing an insulating layer over said substrate and around said gate electrode; establishing a contact hole in said insulating layer to said source region; establishing a polysilicon film located directly over and in direct contact with the source region in said contact hole, the polysilicon film also being located over said insulating layer; establishing a lower electrode over said polysilicon film; establishing a ferroelectric film over said lower electrode; etching said lower electrode and said ferroelectric film; etching said polysilicon film so that said polysilicon film is in said contact hole and over a portion of said insulating layer; and establishing an upper electrode over said ferroelectric film.
Claim 3
Dependent Claim
31 words
The method of claim 1 wherein said polysilicon film is established by chemically vapor growing said film and has a thickness at least equal to the thickness of the insulating layer.
Claim 4
Dependent Claim
33 words
The method of claim 1 further comprising the steps of establishing a second insulating layer over said insulating layer and defining a wiring electrode in said second insulating layer to said drain region.
Claim 5
Dependent Claim
102 words
A semiconductor device comprising: a substrate with a source region and a drain region located therein; a gate electrode located over said substrate and between said source region and said drain region; an insulating layer located over said substrate and around said gate electrode; a polysilicon film located in a contact hole in said insulating layer and located directly over and in direct contact with said source region and located over a portion of said insulating layer; a lower electrode located over said polysilicon film; a ferroelectric film located over said lower electrode; and an upper electrode located over said ferroelectric film.
Claim 6
Dependent Claim
102 words
A semiconductor device comprising: a substrate with a source region and a drain region located therein; a gate electrode located over said substrate and between said source region and said drain region; an insulating layer located over said substrate and around said gate electrode; a polysilicon film located in a contact hole in said insulating layer and located directly over and in direct contact with said source region and located over a portion of said insulating layer; a lower electrode located over said polysilicon film; a ferroelectric film located over said lower electrode; and an upper electrode located over said ferroelectric film.
Claim 7
Dependent Claim
22 words
The device of claim 4 wherein said lower electrode is comprised of a element from the group comprises of platinum and palladium.
Claim 8
Dependent Claim
13 words
The device of claim 4 wherein said ferroelectric film is comprised of PZT.
Claim 9
Dependent Claim
13 words
The device of claim 4 wherein said upper electrode is comprised of aluminum.
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