Francisco A Santiago

US Patent:

6881669, Apr 19, 2005

Filed:

May 9, 2001

Appl. No.:

09/853925

Inventors:

Tak Kin Chu - Bethesda MD, US
Francisco Santiago - Fredericksburg VA, US
Kevin A. Boulais - Waldorf MD, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H01L021/44
H01L021/4763

US Classification:

438653, 438627, 438643

Abstract:

An epitaxial barrier material provides not only a unique growth medium for growing single crystal structures of elemental metal thereon, but also provides an effective diffusion barrier at extremely thin thicknesses against migration of atoms from the metallization layer into an adjacent semiconductor substrate or low dielectric insulation layer. This invention is particularly advantageous for forming single crystal, transition metal conductor lines, contacts, filled trenches, and/or via plugs, and especially conductor structures based on transition metals of copper, silver, gold, or platinum. These metals are highly attractive for interconnect strategies on account of there respective low resistivity and high reliability characteristics. Processes for making the barrier film in a semiconductor device are also covered. The capability to use copper interconnect strategies coupled with the proviso of an extremely thin barrier film makes possible a significant increase in the component density and a corresponding reduction in the number of layers in large scale integrated circuits, as well as improved performance.

US Patent:

7525711, Apr 28, 2009

Filed:

Aug 16, 2006

Appl. No.:

11/504859

Inventors:

Donald W. Rule - Silver Spring MD, US
Kevin A. Boulais - Waldorf MD, US
Francisco Santiago - Fredericksburg VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G02F 1/03
G02F 1/00
H01P 7/00

US Classification:

359244, 359321, 359241, 333235

Abstract:

In one general aspect, a tunable electromagnetic metamaterial as described herein includes a substrate and an array of split ring resonators formed on the substrate. At least one of the split ring resonators is a capacitively tuned split ring resonator. The capacitively tuned split ring resonator includes a structure having a gap and is formed of an electrically conductive material. The capacitively tuned split ring resonator also includes a region of photo-capacitive material formed in close proximity to the structure such that the capacitance of the metamaterial is changed when illuminated by controlling electromagnetic radiation having a selected range of wavelengths.

US Patent:

7864394, Jan 4, 2011

Filed:

Apr 9, 2009

Appl. No.:

12/420840

Inventors:

Donald W. Rule - Silver Spring MD, US
Kevin A. Boulais - Waldorf MD, US
Francisco Santiago - Fredericksburg VA, US

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G02F 1/03

US Classification:

359244, 359241

Abstract:

A dynamically variable lens is made from actively tunable electromagnetic metamaterial cells. The lens operates on electromagnetic radiation including: radio frequency waves, microwaves, teraherz waves, near infrared waves, infrared waves and visible waves. The focal length of the lens is changed at a selected frequency. In the alternative, the frequency of radiation operated on is changed as a function of time. A third alternative provides precise control of the index of refraction of the lens. The index of refraction is varied progressively across the lens from one edge to the opposite edge causing the radiation to be directed at an angle.

US Patent:

48533394, Aug 1, 1989

Filed:

Jul 27, 1988

Appl. No.:

7/224962

Inventors:

Tak-Kin Chu - Bethesda MD
Francisco Santiago - Elkridge MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H01L 3118
H01L 2144

US Classification:

437 2

Abstract:

In a process of preparing an infrared sensitive photodiode comprising the eps of (1) forming by vacuum deposition an epitaxial layer of a semiconductor alloy material selected from the group consisting of PbS, PbSe, PbTe, PbS. sub. x Se. sub. 1-x, PbS. sub. x Te. sub. 1-x, PbSe. sub. x Te. sub. 1-x, Pb. sub. y Sn. sub. 1-y S, Pb. sub. y Sn. sub. 1-y Se, Pb. sub. y Sn. sub. 1-y Te, Pb. sub. y Sn. sub. 1-y S. sub. x, Pb. sub. y Sn. sub. 1-y S. sub. x Te. sub. 1-x, Pb. sub. y Sn. sub. 1-y Se. sub. x Te. sub. 1-x, Pb. sub. z Cd. sub. 1-z S, Pb. sub. z Cd. sub. 1-z Se, Pb. sub. z Cd. sub. 1-z Te, Pb. sub. z Cd. sub. 1-z S. sub. x Se. sub. 1-x, Pb. sub. z Cd. sub. 1-z S. sub. x Te. sub. 1-x, and Pb. sub. z Cd. sub. 1-z Se. sub. x Te. sub. 1-x, wherein 0

US Patent:

54352649, Jul 25, 1995

Filed:

May 19, 1994

Appl. No.:

8/246209

Inventors:

Francisco Santiago - Elkridge MD
Tak K. Chu - Bethesda MD
Michael F. Stumborg - Bethesda MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

C30B 2518

US Classification:

117 92

Abstract:

A process for growing single crystal epitaxial BaF. sub. 2 layers on gallium arsenide substrates by slowly reacting BaF. sub. 2 vapor with the clean, hot GaAs substrate at 500. degree. to 700. degree. C. in high vacuum until a uniform, thin (. about. 12. ANG. ) layer of reaction product is formed and then vapor depositing BaF. sub. 2 onto the reaction layer at room temperature to 400. degree. C. to form the single crystal, epitaxial BaF. sub. 2 layer.

US Patent:

56907370, Nov 25, 1997

Filed:

May 31, 1995

Appl. No.:

8/454983

Inventors:

Francisco Santiago - Elkridge MD
Tak-Kin Chu - Bethesda MD
Michael Stumborg - Rockville MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

C30B 2518

US Classification:

117 92

Abstract:

A process for growing single crystal epitaxial BaF. sub. 2 layers on gallium rsenide substrates by slowly reacting Ba, BaCl. sub. 2, Bal. sub. 2, BaBr. sub. 2, BaF. sub. 2. cndot. BaCl. sub. 2, BaF. sub. 2. cndot. BaBr. sub. 2, BaF. sub. 2. cndot. BaI. sub. 2, BaCl. sub. 2. cndot. BaBr. sub. 2, Ba. sub. 3 (GaF. sub. 6). sub. 2, BAH. sub. 2, or BaO. sub. 2 vapor with a clean, hot GaAs substrate at 500. degree. C. to 700. degree. C. in high vacuum until a uniform, thin (. about. 12. ANG. ) layer of reaction product is formed and then vapor depositing BaF. sub. 2 onto the reaction layer at room temperature to 400. degree. C. to form the single crystal, epitaxial BaF. sub. 2 layer.

US Patent:

49003739, Feb 13, 1990

Filed:

Jul 19, 1989

Appl. No.:

7/381880

Inventors:

Tak-Kin Chu - Bethesda MD
Francisco Santiago - Elkridge MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H01L 2144
H01L 2714
H01L 3102
H01L 3118

US Classification:

148 334

Abstract:

In a process for preparing an infrared sentitive photodiode comprising the teps of: (1) forming by vacuum deposition an epitaxial layer of a semiconductor alloy material selected from the group consisting of PbSe, PbTe, PbSe. sub. x Te. sub. 1-x, Pb. sub. y Sn. sub. 1-y Se, Pb. sub. y Sn. sub. 1-y Te, Pb. sub. y Sn. sub. 1-y Se. sub. x Te. sub. 1-x, Pb. sub. z Cd. sub. 1-z Se, Pb. sub. z Cd. sub. 1-z Te, and Pb. sub. z Cd. sub. 1-z Se. sub. x Te. sub. 1-x, wherein 0

US Patent:

48700274, Sep 26, 1989

Filed:

Jul 27, 1988

Appl. No.:

7/224958

Inventors:

Tak-Kin Chu - Bethesda MD
Francisco Santiago - Elkridge MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H01L 21203
H01L 21363
H01L 2714
H01L 3100

US Classification:

437 3

Abstract:

In a process for preparing an infrared sentitive photodiode comprising the teps of: (1) forming by vacuum deposition an epitaxial layer of a semiconductor alloy material selected from the group consissting of PbSe, PbTe, PbSe. sub. x Te. sub. 1-x, Pb. sub. y Sn. sub. 1-y Se, Pb. sub. y Sn. sub. 1-y Te, Pb. sub. y Sn. sub. 1-y Se. sub. x Te. sub. 1-x, Pb. sub. z Cd. sub. 1-z Se, Pb. sub. z Cd. sub. 1-z Te, and Pb. sub. z Cd. sub. 1-x Se. sub. x Te. sub. 1-x, wherein 0