US3784424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for boron containing glasses useful with semiconductor devices
Assignee: General Electric Co
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Filing: 1971-09-27
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Granted: 1974-01-08
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Expires: 1991-09-27
Abstract
Abstract A glass containing about 5 percent or more by weight boron oxide may be etched using fluoroboric acid as an etchant. The fluoroboric acid etchant is advantageously employed becuase of its comparatively low acidity. The boron oxide containing glass may be utilized as a boron diffusion source in the fabrication of semiconductor devices and may be covered by a barrier layer, such as phosphosilicate glass.
Inventors
- 👤 Yuen Chang Shao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:34
CPC Classifications
C; C03; C03C; C03C15/00; H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P14/00; H10P14/60; H10P32/00; H10P32/10; H10P32/14; H10P32/1408; H10P32/141; H10P32/17; H10P32/171; H10P95/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
68 words
An etching process according to claim 1 in which the glass body is formed as a continuous layer on a silicon semiconductor substrate and contains at least about 20 percent by weight boron oxide, and the substrate with the continuous layer thereon is heated to a temperature sufficient to drive a portion of the boron contained within the glass layer into the substrate prior to applying fluoroboric acid.
Claim 2
Dependent Claim
149 words
An etching process according to claim 1 including forming the glass body as a continuous layer on a silicon semiconductor substrate and to contain at least about 20 percent by weight boron oxide, providing a glass barrier layer comprised of phosphosilicate glass over at least a portion of the continuous layer to prevent outward diffusion of boron and to getter impurities, heating the substrate with the glass layers to a temperature sufficient to drive a portion of the boron contained within the continuous layer into the substrate, forming the resist layer to be substantially inert toward fluoroboric acid and to define an aperture over at least a portion of the barrier layer, removing that portion of the barrier layer that lies within an area defined by the aperture, and applying the fluoroboric acid to the continuous layer within the aperture to form a corresponding aperture within the continuous substrate.
Claim 3
Dependent Claim
160 words
A process for connecting a conductive layer which is supported upon an insulative layer to the surface of a semiconductive substrate comprising forming on an exposed surface of the conductive layer and a laterally adjacent surface of the semiconductive substrate a layer of a glass passivant containing at least about 5 percent by weight boron oxide, forming a layer overlying the glass passivant which is substantially inert to fluoroboric acid and which defines an aperture overlying both the conductive layer and the semiconductive substrate adjacent thereto, applying fluoroboric acid having a pH of from about 5.5 to 7 to the surface portion of the glass passivant layer defined by the aperture in an amount sufficient to permit formation of a corresponding aperture in the glass passivant layer exposing the conductive layer and the semiconductive substrate surface laterally adjacent thereto, and providing an electrically conductive interconnection within the aperture between the conductive layer and the semiconductive substrate surface portion adjacent thereto.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |