Long Quoc Dinh

US Patent:

6351254, Feb 26, 2002

Filed:

Jul 6, 1998

Appl. No.:

09/110166

Inventors:

Long N. Dinh - Concord CA
Mehdi Balooch - Berkeley CA
William McLean, II - Oakland CA
Marcus A. Schildbach - Livermore CA

Assignee:

The Regents of the University of California

International Classification:

G09G 320

US Classification:

345 752, 313310, 3151693

Abstract:

A junction-based field emission display, wherein the junctions are formed by depositing a semiconducting or dielectric, low work function, negative electron affinity (NEA) silicon-based compound film (SBCF) onto a metal or n-type semiconductor substrate. The SBCF can be doped to become a p-type semiconductor. A small forward bias voltage is applied across the junction so that electron transport is from the substrate into the SBCF region. Upon entering into this NEA region, many electrons are released into the vacuum level above the SBCF surface and accelerated toward a positively biased phosphor screen anode, hence lighting up the phosphor screen for display. To turn off, simply switch off the applied potential across the SBCF/substrate. May be used for field emission flat panel displays.

US Patent:

7118630, Oct 10, 2006

Filed:

Aug 10, 2000

Appl. No.:

09/636134

Inventors:

Mehdi Balooch - Berkeley CA, US
Long N. Dinh - Concord CA, US
Wigbert J. Siekhaus - Berkeley CA, US

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

C23C 16/00

US Classification:

118726, 427596, 427597

Abstract:

Short-wavelength photons are used to ablate material from a low work function target onto a suitable substrate. The short-wavelength photons are at or below visible wavelength. The elemental composition of the deposit is controlled by the composition of the target and the gaseous environment in which the ablation process is performed. The process is carried out in a deposition chamber to which a short-wavelength laser is mounted and which includes a substrate holder which can be rotated, tilted, heated, or cooled. The target material is mounted onto a holder that spins the target during laser ablation. In addition, the deposition chamber is provided with a vacuum pump, an external gas supply with atomizer and radical generator, a gas generator for producing a flow of molecules on the substrate, and a substrate cleaning device, such as an ion gun. The substrate can be rotated and tilted, for example, whereby only the tip of an emitter can be coated with a low work function material.

US Patent:

62356151, May 22, 2001

Filed:

Feb 15, 2000

Appl. No.:

9/504302

Inventors:

Long N. Dinh - Concord CA
William McLean - Oakland CA
Mehdi Balooch - Berkeley CA
Edward J. Fehring - Dublin CA
Marcus A. Schildbach - Livermore CA

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H01L 2120
H01L 2136

US Classification:

438487

Abstract:

Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500. degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

US Patent:

61627070, Dec 19, 2000

Filed:

May 18, 1998

Appl. No.:

9/080096

Inventors:

Long N. Dinh - Concord CA
William McLean - Oakland CA
Mehdi Balooch - Berkeley CA
Edward J. Fehring - Dublin CA
Marcus A. Schildbach - Livermore CA

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H01L 2120

US Classification:

438487

Abstract:

Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500. degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

US Patent:

61208574, Sep 19, 2000

Filed:

May 18, 1998

Appl. No.:

9/080109

Inventors:

Mehdi Balooch - Berkeley CA
Long N. Dinh - Concord CA
Wigbert J. Siekhaus - Berkeley CA

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

C23C 1428
B05D 512

US Classification:

427596

Abstract:

Short-wavelength photons are used to ablate material from a low work function target onto a suitable substrate. The short-wavelength photons are at or below visible wavelength. The elemental composition of the deposit is controlled by the composition of the target and the gaseous environment in which the ablation process is performed. The process is carried out in a deposition chamber to which a short-wavelength laser is mounted and which includes a substrate holder which can be rotated, tilted, heated, or cooled. The target material is mounted onto a holder that spins the target during laser ablation. In addition, the deposition chamber is provided with a vacuum pump, an external gas supply with atomizer and radical generator, a gas generator for producing a flow of molecules on the substrate, and a substrate cleaning device, such as an ion gun. The substrate can be rotated and tilted, for example, whereby only the tip of an emitter can be coated with a low work function material.

US Patent:

6019913, Feb 1, 2000

Filed:

May 18, 1998

Appl. No.:

9/080110

Inventors:

Long N. Dinh - Concord CA
Mehdi Balooch - Berkeley CA
Marcus A. Schildbach - Livermore CA
Alex V. Hamza - Livermore CA
William McLean - Oakland CA

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H01J 902

US Classification:

252516

Abstract:

Low work function, stable compound clusters are generated by co-evaporation of a solid semiconductor (i. e. , Si) and alkali metal (i. e. , Cs) elements in an oxygen environment. The compound clusters are easily patterned during deposition on substrate surfaces using a conventional photo-resist technique. The cluster size distribution is narrow, with a peak range of angstroms to nanometers depending on the oxygen pressure and the Si source temperature. Tests have shown that compound clusters when deposited on a carbon substrate contain the desired low work function property and are stable up to 600. degree. C. Using the patterned cluster containing plate as a cathode baseplate and a faceplate covered with phosphor as an anode, one can apply a positive bias to the faceplate to easily extract electrons and obtain illumination.