Patent US143835A successfully refreshed from Google Patents.
Patent US882926A successfully refreshed from Google Patents.
Patent US5840200A successfully refreshed from Google Patents.
US5840200A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing semiconductor devices
Assignee: Panasonic Holdings Corp
•
Filing: 1997-01-24
•
Granted: 1998-11-24
•
Expires: 2017-01-24
Abstract
Abstract A device insulating film, a lower-layer platinum film, a ferroelectric film, an upper-layer platinum film, and a titanium film are sequentially formed on a semiconductor substrate in this order. On the titanium film, a photoresist mask is further formed in a desired pattern. The thickness of the titanium film is adjusted to be 1/10 or more of the total thickness of a multilayer film consisting of the upper-layer platinum film, the ferroelectric film, and the lower-layer platinum film. The titanium film is then subjected to dry etching and the photoresist film is removed by ashing process. The titanium film thus patterned is used as a mask in etching the upper-layer platinum film, the ferroelectric film, and the lower-layer platinum film by a dry-etching method using a plasma of a gas mixture of chlorine and oxygen in which the volume concentration of oxygen gas is adjusted to be 40%. During the dry-etching process, the titanium film is oxidized to provide a high etching selectivity. Subsequently, the titanium film is removed by dry etching using a plasma of chlorine gas.
Inventors
- 👤 Satoshi Nakagawa
- 👤 Toyoji Ito
- 👤 Yoji Bito
- 👤 Yoshihisa Nagano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:37
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/28; H10P50/282; H10P50/283; H10P50/285
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
87 words
A method of manufacturing semiconductor devices, comprising the steps of: forming a film to be etched on a semiconductor substrate, said film to be etched being made of at least one of a ferroelectric material, a high dielectric constant material, and platinum; forming a patterned mask made of a metal to be oxidized on said film to be etched; and selectively etching said film to be etched by using said patterned mask as an etching mask and a plasma of a gas mixture of chlorine and oxygen.
Claim 2
Independent Claim
87 words
A method of manufacturing semiconductor devices, comprising the steps of: forming a film to be etched on a semiconductor substrate, said film to be etched being made of at least one of a ferroelectric material, a high dielectric constant material, and platinum; forming a patterned mask made of a metal to be oxidized on said film to be etched; and selectively etching said film to be etched by using said patterned mask as an etching mask and a plasma of a gas mixture of chlorine and oxygen.
Claim 3
Dependent Claim
35 words
A method according to claim 1, wherein said step of forming the mask comprises the step of forming a film made of at least one of titanium, a titanium compound, and an alloy containing titanium.
Claim 4
Dependent Claim
37 words
A method according to claim 1, wherein said step of selectivity etching the film to be etched comprises the step of adjusting a volume concentration of oxygen gas in said gas mixture to be 30% or more.
Claim 5
Independent Claim
105 words
A method of manufacturing semiconductor devices, comprising the steps of: forming a film to be etched on a semiconductor substrate, said film to be etched being made of at least one of a ferroelectric material and a high dielectric constant material; forming a patterned multilayer mask on said film to be etched, said multilayer mask comprising a lower-layer mask made of an insulating material and an upper-layer mask made of a metal likely to be oxidized on said lower-layer mask; selectively etching said film to be etched by using an oxidizing and halogenating gas plasma; and removing said upper-layer mask while leaving said lower-layer mask.
Claim 6
Independent Claim
105 words
A method of manufacturing semiconductor devices, comprising the steps of: forming a film to be etched on a semiconductor substrate, said film to be etched being made of at least one of a ferroelectric material and a high dielectric constant material; forming a patterned multilayer mask on said film to be etched, said multilayer mask comprising a lower-layer mask made of an insulating material and an upper-layer mask made of a metal likely to be oxidized on said lower-layer mask; selectively etching said film to be etched by using an oxidizing and halogenating gas plasma; and removing said upper-layer mask while leaving said lower-layer mask.
Claim 7
Dependent Claim
25 words
A method according to claim 4, wherein said step of forming the lower-layer mask comprises the step of forming a film made of silicon oxide.
Claim 8
Dependent Claim
36 words
A method according to claim 4, wherein said step of forming the upper-layer mask comprises the step of forming a film made of at least one of titanium, a titanium compound, and an alloy containing titanium.
Claim 9
Dependent Claim
43 words
A method according to claim 6, wherein said step of removing the upper-layer mask comprises the step of etching said upper-layer mask by using a reducing gas plasma under such a condition that titanium and titanium oxide are etched at the same rate.
Claim 10
Dependent Claim
26 words
A method according to claim 7, wherein said step of removing the upper-layer mask comprises the step of selecting a reducing gas plasma of boron trichloride.
Claim 11
Independent Claim
104 words
A method of manufacturing semiconductor devices, comprising the steps of: forming a film to be etched on a semiconductor substrate, said film to be etched being made of at least one of a ferroelectric material and a high dielectric constant material; forming an electrode pattern made of platinum on said film to be etched; forming a patterned mask made of an insulating material on said film to be etched, said patterned mask being larger than said electrode pattern and covering said electrode pattern; and selectively etching said film to be etched by using said patterned mask as an etching mask and a gas plasma.
Claim 12
Independent Claim
104 words
A method of manufacturing semiconductor devices, comprising the steps of: forming a film to be etched on a semiconductor substrate, said film to be etched being made of at least one of a ferroelectric material and a high dielectric constant material; forming an electrode pattern made of platinum on said film to be etched; forming a patterned mask made of an insulating material on said film to be etched, said patterned mask being larger than said electrode pattern and covering said electrode pattern; and selectively etching said film to be etched by using said patterned mask as an etching mask and a gas plasma.
References Cited (Backward Citations)
US3836446A
Cited
US3975252A
Cited
JPS60247816A
Cited
JPS61248048A
Cited
JPS6292323A
Cited
JPS62120019A
Cited
JPH0589662A
Cited
US5254217A
Cited
JPH07130712A
Cited
US5443688A
Cited
JPH07221070A
Cited
JPH08181128A
Cited
JPH0883756A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-11-23 | 2002-05-25 | 2002-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-23 | 2006-05-25 | 2006-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-23 | 2010-05-25 | 2010-11-24 | $7700.00 | Window Closed / Lapsed |