Patent US2858641A successfully refreshed from Google Patents.
Patent EP0273702A2 successfully refreshed from Google Patents.
EP0273702A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Radiation hardening techniques for metal-oxide silicon devices
Assignee: General Electric Co
•
Filing: 1987-12-23
•
Granted: —
•
Expires: 2007-12-23
Abstract
Abstract Techniques for improving the radiation hardness of CMOS VLSI devices manufactured using a standard commercial process are disclosed. The techniques include a boron bird's beak implant after a field oxide is grown by the LOCOS process. The radiation hardness of the devices is further enhanced by a bird's beak etch to form a self-aligned guard ring.
Inventors
- 👤 Ching-Yeu Wei
- 👤 Henry Hugh Woodbury
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 06:17
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/0188; H10D84/02; H10D84/03; H10D84/038; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10D84/858; H10P; H10P30/00; H10P30/20; H10P30/22; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/0125; H10W10/0126; H10W10/0127; H10W10/10; H10W10/13
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
71 words
A process for radiation hardening very large scale integrated circuits including metal oxide silicon devices produced using a retrograde P-well process, comprising the steps of: forming a local oxidation of silicon field isolation for each of said devices, said local oxidation producing a bird's beak structure; implanting boron ions in the region of the bird's beak structure; and etching the field oxide to remove a portion of the bird's beak structure.
Claim 2
Dependent Claim
71 words
A process for radiation hardening very large scale integrated circuits including metal oxide silicon devices produced using a retrograde P-well process, comprising the steps of: forming a local oxidation of silicon field isolation for each of said devices, said local oxidation producing a bird's beak structure; implanting boron ions in the region of the bird's beak structure; and etching the field oxide to remove a portion of the bird's beak structure.
Claim 3
Dependent Claim
35 words
The process for radiation hardening recited in claim 1 wherein the step of implanting is performed using boron ions having an energy of approximately 250 keV to produce an implant dose of approximately 2x10¹³ ions/cm².
Claim 4
Dependent Claim
33 words
The process for radiation hardening recited in claim 1 wherein the step of etching removes 1000Å to 2000Å of a field oxide to form a self-aligned guard ring with a higher threshold voltage.
Claim 5
Dependent Claim
32 words
The process for radiation hardening recited in claim 2 wherein the step of etching removes 1000Å to 2000Å of field oxide to form a self-aligned guard ring with a higher threshold voltage.
Claim 6
Dependent Claim
63 words
A process for radiation hardening an NMOS semiconductor device comprising the steps of: forming a local oxidation of semiconductor to provide field isolation for said device, said local oxidation producing a bird's beak structure including a tip; implanting boron ions in the region of the bird's beak structure including the tip; and removing a portion of the bird's beak structure including the tip.
Claim 7
Dependent Claim
63 words
A process for radiation hardening an NMOS semiconductor device comprising the steps of: forming a local oxidation of semiconductor to provide field isolation for said device, said local oxidation producing a bird's beak structure including a tip; implanting boron ions in the region of the bird's beak structure including the tip; and removing a portion of the bird's beak structure including the tip.
Claim 8
Dependent Claim
40 words
The process for radiation hardening recited in claim 5 wherein said semiconductor comprises silicon and the step of implanting is performed using boron ions having an energy of approximately 250 keV to produce an implant dose of approximately 2x10¹³ ions/cm².
Claim 9
Dependent Claim
32 words
The process for radiation hardening recited in claim 5 wherein the step of etching removes 1000Å to 2000Å of field oxide to form a self-aligned guard ring with a higher threshold voltage.
Claim 10
Dependent Claim
32 words
The process for radiation hardening recited in claim 6 wherein the step of etching removes 1000Å to 2000Å of field oxide to form a self-aligned guard ring with a higher threshold voltage.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.