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US3933530A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of radiation hardening and gettering semiconductor devices

Assignee: RCA Corp
•
Filing: 1975-01-28
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Granted: 1976-01-20
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Expires: 1995-01-28
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Abstract

Abstract In one embodiment, a semiconductor device, such as an insulated-gate-field-effect-transistor (IGFET), is simultaneously radiation hardened with Al ions and its threshold voltage stabilized with halide ions, such as Cl ions, by bombarding a silicon dioxide gate insulator of the device with molecular ions of an aluminum halide, such as AlCl 2 + ions. In another embodiment, a surface (target) of silicon is bombarded with molecular AlCl 2 + ions to ion implant separate Al ions and Cl ions. There, an oxide layer subsequently thermally grown on the bombarded surface includes the Al ions and the Cl ions, and the oxide layer is radiation hardened and gettered.

Inventors

  • 👤 Charles William Mueller
  • 👤 Edward Curtis Douglas
  • 👤 Chung Pao Wu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 07:16
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/40; H10D; H10D99/00; Y; Y10; Y10S; Y10S257/00; Y10S257/906; Y10S438/00; Y10S438/953

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 121 words
A method of radiation hardening and gettering a layer of silicon dioxide formed on a body of semiconductor material during the manufacture of a semiconductor device, said method comprising the steps of: providing a source of molecular aluminum halide ions, and accelerating said molecular aluminum halide ions towards said body, on an impact course, with a kinetic energy that is greater than the molecular binding energy of said molecular aluminum halide ions so that each of said molecular aluminum halide ions breaks up into Al ions and halide ions upon impact, whereby each of said Al ions and halide ions assumes an ion-implantation energy substantially proportional to the ratio of its mass to the mass of said molecular aluminum halide ions.
Claim 2
Independent Claim 121 words
A method of radiation hardening and gettering a layer of silicon dioxide formed on a body of semiconductor material during the manufacture of a semiconductor device, said method comprising the steps of: providing a source of molecular aluminum halide ions, and accelerating said molecular aluminum halide ions towards said body, on an impact course, with a kinetic energy that is greater than the molecular binding energy of said molecular aluminum halide ions so that each of said molecular aluminum halide ions breaks up into Al ions and halide ions upon impact, whereby each of said Al ions and halide ions assumes an ion-implantation energy substantially proportional to the ratio of its mass to the mass of said molecular aluminum halide ions.
Claim 3
Dependent Claim 48 words
A method of radiation hardening and gettering a layer of silicon dioxide as described in claim 1, wherein: said molecular aluminum halide ions are caused to impact with said layer of silicon dioxide on said body, whereby to implant said ions of Al and halide in said layer.
Claim 4
Dependent Claim 68 words
A method of radiation hardening and gettering a layer of silicon dioxide as described in claim 1, wherein: said molecular aluminum halide ions are caused to impact with a surface of said body of semiconductor material for implantation therein, said semiconductor material is silicon, and said surface is thereafter thermally oxidized to form said layer of silicon dioxide, whereby said layer contains said ions of Al and halide.
Claim 5
Dependent Claim 56 words
A method of radiation hardening and gettering a layer of silicon dioxide as described in claim 1, wherein: the step of providing a source of molecular aluminum halide ions comprises vaporizing an aluminum halide chosen from the group consisting of aluminum fluoride, aluminum chloride, aluminum bromide, aluminum iodide, and mixtures thereof in a hot-filament ion source.
Claim 6
Dependent Claim 37 words
A method of radiation hardening and gettering a layer of silicon dioxide as described in claim 1, wherein: said semiconductor device is an IGFET, and said layer of silicon dioxide is a gate dielectric of said IGFET.
Claim 7
Dependent Claim 34 words
A method of radiation hardening and gettering a layer of silicon dioxide as described in claim 1, wherein: said layer of silicon dioxide is annealed after said Al and halide ions are implanted therein.
Claim 8
Dependent Claim 41 words
A method of radiation hardening and gettering a layer of silicon dioxide as described in claim 1, wherein: said molecular aluminum halide ions are derived by vaporizing AlCl 3 in a hot filament source to obtain molecular AlCl 2 + ions.

References Cited (Backward Citations)

US3556878A Cited
US3570112A Cited
US3799813A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-01-19 1979-07-21 1980-01-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-01-19 1983-07-21 1984-01-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-01-19 1987-07-21 1988-01-20 $7700.00 Window Closed / Lapsed

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