Oxidation of silicon using fluorine implant

Details Oxidation of silicon using fluorine implant Oxidation of silicon using fluorine implant

1999-05-14

2002-03-19

Booth, Richard (Department: 2812)

Semiconductor device manufacturing: process

Coating of substrate containing semiconductor region or of...

Multiple layers

C438S981000, C438S264000

Reexamination Certificate

active

06358865

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates a method for the oxidation of silicon and the formation of silicon oxide regions by implantation of fluorine into the silicon lattice and subsequently forming an oxide region by a typical oxide growth process.
BACKGROUND OF THE INVENTION
In the fabrication of a MOS (metal oxide semiconductor) semiconductor device, it is essential to form a gate oxide film by oxidation. The properties of a gate oxide film are greatly influenced by the atmosphere under which the film is formed. Accordingly, an oxide film can be deposited by processes differing from each other in atmospheric conditions. For instance, a silicon oxide film can be deposited by any of the processes belonging to, for example, the families of dry oxidation and wet oxidation. The dry oxidation process comprises supplying a sufficiently dried high purity oxygen to the surface of a hot silicon substrate. In this manner, a silicon oxide film can be formed on the surface of the silicon substrate. The wet oxidation process comprises supplying, to the surface of a silicon substrate, a hot carrier gas containing water vapor. This process also provides a silicon oxide film on the surface of the silicon substrate.
The presence of either chlorine or fluorine in an ambient of dry oxygen is known to accelerate the oxidation rate. It is known that a dry oxidation method to form a silicon oxide film under an oxidizing atmosphere based on a compound containing chlorine (e.g., HCl, Cl
2
, CCl
4
, C
2
HCl
3
, CH
2
Cl
2
, and C
2
H
3
Cl
3
) or a compound containing a halogen atom other than chlorine provides a silicon oxide film which yields an oxide film thicker than that produced by the dry oxidation method alone. In this regard, fluorine is much more efficient than chlorine. Typically, chlorine is added as a percentage of the total oxygen flow, whereas fluorine on the order of parts-per-million will have a noticeable effect on the oxidation rate.
However, these prior art processes often require additional processing steps, such as annealing, to form a sufficient oxide layer. Additionally, the prior art methods do not allow the growth of the field oxide regions and the gate oxide regions during a single oxide growth step. The present invention overcomes the drawbacks of the prior art methods.
SUMMARY OF THE INVENTION
The present invention relates to method for the oxidation of a semiconductor substrate and the formation of oxide regions or layers by implantation of fluorine into the silicon lattice and subsequently forming an oxide region by a typical oxide growth process. The oxide growth process may be a thermal oxidation process such as dry or wet ambient oxidation processes.
The oxide growth depends upon the amount of fluorine implanted into the substrate, the depth which the fluorine is implanted and the energy at which the fluorine is implanted. The process according to the present invention allows for the simultaneous growth of oxides having different thicknesses at the same time by tailoring the fluorine implantation. Additional advantages of the present invention will be apparent from the detailed description and drawings, which illustrate preferred embodiments of the invention.


REFERENCES:
patent: 4743563 (1988-05-01), Pfiester et al.
patent: 5480828 (1996-01-01), Hsu et al.
patent: 5576226 (1996-11-01), Hwang
patent: 5614421 (1997-03-01), Yang
patent: 5672521 (1997-09-01), Barsan et al.
patent: 5902128 (1999-05-01), Mathews et al.
patent: 5937310 (1999-08-01), Gardner et al.
patent: 6087237 (2000-07-01), Hwang
patent: 6091109 (2000-07-01), Hasegawa
patent: 6150220 (2000-11-01), Huh et al.
patent: 55085068 (1980-06-01), None
patent: 62177930 (1987-08-01), None
patent: 03163876 (1991-07-01), None
patent: 05074762 (1993-03-01), None
patent: 05217931 (1993-08-01), None
patent: 07240409 (1995-09-01), None
patent: 09055380 (1997-02-01), None
patent: 11330263 (1998-05-01), None
Tan Khai Nguyen, et al., Effects of Fluorine Implants on Induced Charge Components in Gate-Oxides Under Constant-Current Fowler-Nordheim Stress, IEEE Transaction on Electron Devices, vol. 44, No. 9, Sep. 1997.
B. Holm et al., Formation of Shallow Donor in Fluorine-Implanted Silicon, J. Appl. Phys. 79 (3), Feb. 1, 1998.
T. P. Chen et al., Investigation on the Distribution of Fluorine and Boron in Polycrystalline Silicon/Silicon Systems, J. Electrochem. Soc., vol. 142, No. 6, Jun. 1995.
Yang-Jlk Park, et al. Fluorine Implantation effect on baron diffusion in Si, Journal of Applied Physics, vol. 85, No. 2, Jan. 15, 1999.

Affiliated with

Also associated with

Rating

Oxidation of silicon using fluorine implant does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Oxidation of silicon using fluorine implant, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Oxidation of silicon using fluorine implant will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2826929