US4755865A
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Means for stabilizing polycrystalline semiconductor layers
Assignee: NXP USA Inc
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Filing: 1987-04-09
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Granted: 1988-07-05
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Expires: 2007-04-09
Abstract
Abstract Implantation of oxygen or nitrogen in polysilicon layers to a dose above about 10 15 ions/cm 2 retards rapid grain boundary migration of conventional dopants such as B, P, As, Sb, and the like during dopant activation. Pre-annealing of the poly films to increase the grain size also decreases rapid grain boundary migration. The effects can be combined by first pre-annealing and then implanting oxygen or nitrogen before introducing the dopant. It is desirable to anneal the oxygen implant before introducing the dopant to allow for oxygen diffusion to the grain surfaces where it precipitates and blocks the grain boundaries. Vertical and lateral migration of the dopants can be inhibited by placing the implanted oxygen or nitrogen between the dopant and the location desired to be kept comparatively free of dopants. When very high dopant activation temperatures are used the blocking effect of the oxygen on the grain boundaries is overwhelmed by dopant diffusion through the grains.
Inventors
- 👤 Syd. R. Wilson
- 👤 Richard B. Gregory
- 👤 Charles J. Varker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:30
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/40; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/01338; H10P; H10P32/00; H10P32/30; H10P32/302
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
85 words
A semiconductor device comprising: a substrate; a polycrystalline semiconductor layer having a first surface in contact with said substrate and a second surface opposite said first surface; a first region within said polycrystalline semiconductor layer containing oxygen at a concentration in the range 10 19 to 10 21 atoms/cm 3 ; a second region in said polycrystalline semiconductor layer containing a peak concentration of a conductivity altering dopant; and wherein a portion of said first region lies between said second region and said first surface.
Claim 2
Dependent Claim
85 words
A semiconductor device comprising: a substrate; a polycrystalline semiconductor layer having a first surface in contact with said substrate and a second surface opposite said first surface; a first region within said polycrystalline semiconductor layer containing oxygen at a concentration in the range 10 19 to 10 21 atoms/cm 3 ; a second region in said polycrystalline semiconductor layer containing a peak concentration of a conductivity altering dopant; and wherein a portion of said first region lies between said second region and said first surface.
Claim 3
Dependent Claim
23 words
The device of claim 1 wherein said first region has a thickness of at least one-fourth the thickness of said polycrystalline semiconductor layer.
Claim 4
Dependent Claim
85 words
A semiconductor device comprising: a substrate; a polycrystalline semiconductor layer having a first surface in contact with said substrate and a second surface opposite said first surface; a first region within said polycrystalline semiconductor layer containing oxygen at a concentration in the range 10 19 to 10 21 atoms/cm 3 ; a second region in said polycrystalline semiconductor layer containing a peak concentration of a conductivity altering dopant; and wherein a portion of said first region lies between said second region and said second surface.
Claim 5
Dependent Claim
85 words
A semiconductor device comprising: a substrate; a polycrystalline semiconductor layer having a first surface in contact with said substrate and a second surface opposite said first surface; a first region within said polycrystalline semiconductor layer containing oxygen at a concentration in the range 10 19 to 10 21 atoms/cm 3 ; a second region in said polycrystalline semiconductor layer containing a peak concentration of a conductivity altering dopant; and wherein a portion of said first region lies between said second region and said second surface.
Claim 6
Dependent Claim
23 words
The device of claim 3 wherein said first region has a thickness of at least one-fourth the thickness of said polycrystalline semiconductor layer.
Claim 7
Dependent Claim
69 words
A semiconductor device comprising: a substrate having an insulating surface; a polycrystalline semiconductor layer on said insulating surface, wherein said polycrystalline layer has a first region doped with a first dopant a second region substantially free of said first dopant, and a third region containing oxygen or nitrogen at a concentration in the range 10 19 to 10 21 atoms/cm 3 located laterally between said first and second regions.
Claim 8
Dependent Claim
69 words
A semiconductor device comprising: a substrate having an insulating surface; a polycrystalline semiconductor layer on said insulating surface, wherein said polycrystalline layer has a first region doped with a first dopant a second region substantially free of said first dopant, and a third region containing oxygen or nitrogen at a concentration in the range 10 19 to 10 21 atoms/cm 3 located laterally between said first and second regions.
Claim 9
Dependent Claim
75 words
A semiconductor device comprising: a substrate having an insulating surface; a polycrystalline semiconductor layer on said insulating surface, wherein said polycrystalline layer has a first region doped with a first dopant, a second region substantially free of said first dopant, and a third region implanted with oxygen or nitrogen to a dose in the range from more than 10 14 to less than 10 17 ions/cm 2 located laterally between said first and second regions.
Claim 10
Dependent Claim
75 words
A semiconductor device comprising: a substrate having an insulating surface; a polycrystalline semiconductor layer on said insulating surface, wherein said polycrystalline layer has a first region doped with a first dopant, a second region substantially free of said first dopant, and a third region implanted with oxygen or nitrogen to a dose in the range from more than 10 14 to less than 10 17 ions/cm 2 located laterally between said first and second regions.
Claim 11
Dependent Claim
23 words
The semiconductor device of claim 31 wherein said dose is in the range from 10 15 to about 10 16 ions/cm 2 .
References Cited (Backward Citations)
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