Patent US3725150A successfully refreshed from Google Patents.
US3725150A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making a fine geometry, self-aligned device structure
Assignee: Motorola Solutions Inc
•
Filing: 1971-10-29
•
Granted: 1973-04-03
•
Expires: 1991-10-29
Abstract
Abstract A fine geometry, self-aligned device structure is fabricated by interspersing diffusion and pattern steps, including preferential etching, by which line widths of one micron, and pattern repeat distances of five microns in transistors, are easily attained.
Inventors
- 👤 W George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:27
CPC Classifications
H; H10; H10P; H10P95/00; H10D; H10D10/00; H10D10/01; H10D10/051; H10D10/056; H10D10/058; H10W; H10W74/00; H10W74/40; Y; Y10; Y10S; Y10S148/00; Y10S148/043; Y10S148/051; Y10S148/053; Y10S148/106; Y10S148/113; Y10S148/114; Y10S148/122
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
87 words
The process of claim 1 wherein said plurality of layers comprises first, second the third layers of silicon nitride, polycrystalline silicon, and silicon dioxide respectively, and the additional steps of: first etching said polysilicon layer to define said second complementary area before performing said first diffusion to insulate and protect said first and third layers from interreaction and to serve as a mask for a subsequent etch of said first layer; and etching said first layer, using the second layer as a mask, after the first diffusion.
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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |