Texas Instruments Corporation

Jules D Levine

Bruce E Gnade

Robert H Taylor

Chi-Cheong Shen

Millard J Jensen

Kenneth G Vickers

Gregory Barton Hotchkiss

Scott Robert Summerfelt

Chih-Chen Cho

Robert M Wallace

William R McKee

Milfred D Hammerbacher

Kent R Carson

Robert E Yui

Phil E Hecker, Jr

Ronald E Haney

Daron G Evans

Sidney G Parker

David E Witter

Vernon E Knepprath

Paul R Sharrock

Millard J Jensen, Deceased

A field emission display device includes groupings of microtip emitters 14 which are energized by applying a negative potential to cathode 16 relative to the signal electrode 22, thereby inducing an electric field which draws streams of electrons 38 from the apexes of microtips 14. Electrons 38 emitted from microtips 14 impinge upon extraction plate 36 causing emission of a secondary stream of electrons 40 which are accelerated toward anode 40. Apparatus and methods for controlling these primary and secondary electron streams are described.

Bistable field emission display device using secondary emission

A computer image display device includes a light transparent glass anode plate (10) spaced from a cathode substrate (12) which has a plurality of microtips (14). Plate (10) has an inside surface (25) which is contoured with an array of prisms (36) having equal sides (58, 59) that converge rearwardly toward apexes (38) of peaks (36). Apexes (38) are covered with light absorbing material (47), then covered at anode comb forming regions (51, 52, 53) with conductive material (48). Different color luminescing phosphors (24a, 24b, 24c) are applied over the respective anode combs (51, 52, 53). Sides (58, 59) direct ambient light toward apexes (38) for absorption by material (47). Light emitted by phosphors (24a, 24b, 24c) is directed by valleys (60) toward outside surface (35) of plate (10).

Method of making an ambient light absorbing face plate for flat panel

An electron emitter plate (110) for an FED image display has an extraction (gate) electrode (22) spaced by an insulating spacer (125) from a cathode electrode including a conductive mesh (18). Arrays of microtips (14) are located in mesh spacings (16), within apertures (26) formed in extraction electrode (22) and subcavities (141) formed through apertures (26) in insulating spacer (125). Subcavities (141a) are open to row-adjacent and column-adjacent subcavities (141b, 141c) to form larger main cavities (144). Posts (143) of insulating spacer (125) separate diagonally-adjacent cavities (141d). Subcavities (141) are formed by over-etching a layer of insulating spacer material (25) through apertures (26) before or after forming microtips (14) through the same apertures (26). Over-etching reduces the dielectric constant factor of gate-to-cathode capacitance in the finished structure.

Field emission device with over-etched gate dielectric

A grooved anode plate 40 for use in a field emission flat panel display device comprises a transparent planar substrate 42 having a plurality of electrically conductive, parallel stripes 46 comprising the anode electrode of the device, which are covered by phosphors 48.sub.R, 48.sub.G and 48.sub.B. In one embodiment, grooves 50, having generally straight sidewalls, are formed in the upper surface of planar substrate 42 at the interstices of conductors 46. In a second embodiment, grooves 50', which provide a substantial undercutting of the material of substrate 42' adjacent the edges of conductors 46', are formed in the upper surface of planar substrate 42' at the interstices of conductors 46'. A substantially opaque, electrically insulating material 52 is affixed to substrate 42 in the grooves 50 formed between conductors 46, acting as a barrier to the passage of ambient light into and out of the device. The grooves 50 in the surface of substrate 42 and the electrical insulating quality of opaque material 52 increase the electrical isolation of conductive stripes 46 from one another, reducing the risk of breakdown due to increased leakage current. Opaque material 52 preferably comprises glass having impurities dispersed therein, wherein the impurities may include one or more organic dyes, selected to provide relatively uniform opacity over the visible range of the electromagnetic spectrum. Alternatively, the impurities may include the black oxide of a transition metal such as cobalt. Two methods of fabricating grooved anode plate 40 are disclosed.

Flat panel display anode plate having isolation grooves

A method of fabricating electron emission structures 28 having enhanced emission characteristics. The method comprises the steps of providing a substrate 10 having electron emission structures 5 thereon and having a layer 5' over the electron emission structures. The layer 5' having apertures 30 in alignment with said electron emission structures 5. Then modifying the electron emission structures 5 through the apertures 30 with a directional ion milling beam; thereby creating modified electron emission structures 17,29 with enhanced emission efficiency.

Self-aligned method of micro-machining field emission display microtips

An electron emitter plate (110) for an FED image display has an extraction (gate) electrode (22) spaced by an insulating layer (125) from a cathode electrode including a conductive mesh (18). Hexagonal close-packed arrays (12) of microtips (14) are located in mesh spacings (16), within apertures (26) formed in extraction electrode (22). Microtips (14) are formed on a conductive plate (17) laterally spaced from mesh structure (18) by a resistive layer (15). Insulating layer (125) is etched to connect apertures (26) and place microtips (14) in a common cavity within each mesh spacing (16).

Field emission device with close-packed microtip array

An electron emitter plate (110) for an FED image display has an extraction (gate) electrode (22) spaced by a dielectric insulating spacer (125) from a cathode electrode including a conductive mesh (18). Arrays (12) of microtips (14) are located in mesh spacings (16), within apertures (26) formed in clusters (23) in extraction electrode (22). Microtips (14) are deposited through the apertures (26). Apertures (26) are arranged in regular, periodic arrays (23, 23', 123, 123') defining lattices having occupied apertured positions and internal unapertured vacancy positions (150, 150'). The insulating spacer (125) is etched to undercut electrode (22) to connect apertured lattice positions, forming a common cavity (141) for microtips (14) within each mesh spacing (16), and leaving central posts (143) at the unapertured vacancies (150, 150'). The etch-out reduces the dielectric constant factor of gate-to-cathode capacitance in the finished structure. Placing posts at vacancy positions enables gate support over the cavity without sacrificing high microtip density.

Field emission device with lattice vacancy, post-supported gate

An electron emitter plate (110) for an FED image display has an extraction (gate) electrode (22) spaced by a dielectric insulating spacer (125) from a cathode electrode including a conductive mesh (18). Arrays (12) of microtips (14) are located in mesh spacings (16), within apertures (26) formed in clusters (23) in extraction electrode (22). Microtips (14) are deposited through the apertures (26). The insulating spacer (125) is etched to undercut electrode (22) to connect apertures, forming a common cavity (141) for microtips (14) within each mesh spacing (16). Support beam structures (143) are deposited onto extraction electrode (22), either separately or simultaneously with formation of the microtips (14). The support beam structures (143) span the cavity (141) to support the extraction electrode (22) above the cathode electrode over cavity (141). The etch-out reduces the dielectric constant factor of gate-to-cathode capacitance in the finished structure. Strengthening the gate (22) with structures (143) enables gate support over the cavity (141).

Field emission device with suspended gate

An electron emitter plate (110) for an FED image display has an extraction (gate) electrode (22) spaced by a dielectric insulating spacer (125) from a cathode electrode including a conductive mesh (18). Arrays (12) of microtips (14) are located in mesh spacings (16), within apertures (26) formed in clusters (23) in extraction electrode (22). Microtips (14) are deposited through the apertures (26). The insulating spacer (125) is etched to undercut electrode (22) to connect apertures, forming a common cavity (141) for microtips (14) within each mesh spacing (16). Support beam structures (143) are deposited onto extraction electrode (22), either separately or simultaneously with formation of the microtips (14). The support beam structures (143) span the cavity (143) to support the extraction electrode (22) above the cathode electrode over cavity (143). The etch-out reduces the dielectric constant factor of gate-to-cathode capacitance in the finished structure. Strengthening the gate (22) with structures (143) enables gate support over the cavity (141).

An anode plate 50 for use in a field emission flat panel display device comprises a transparent planar substrate 58 having a plurality of electrically conductive, parallel stripes 52 comprising the anode electrode of the device, which are covered by phosphors 54.sub.R, 54.sub.G and 54.sub.B. A substantially opaque, electrically insulating material 56 is affixed to substrate 58 in the spaces between conductors 52, acting as a barrier to the passage of ambient light into and out of the device. The electrical insulating quality of opaque material 56 increases the electrical isolation of conductive stripes 52 from one another, reducing the risk of breakdown due to increased leakage current. Opaque material 56 preferably comprises glass having impurities dispersed therein, wherein the impurities may include one or more organic dyes, selected to provide relatively uniform opacity over the visible range of the electromagnetic spectrum. Alternatively, the impurities may include the black oxide of a transition metal such as cobalt. Opaque material 56 is formed by mixing a TEOS solution with a dye or a source of metallic ions, spinning or spreading the mixture on glass substrate 58, and curing the mixture to drive out the organics and solvents. Two methods of fabricating anode plate 50 are disclosed.

Method of making an anode plate for use in a field emission device

To prevent degradation of field emission in a field emission device (FED) (10) resulting from the accumulation of contaminating impurities on the surface (42) of the microtips (26) of the FED (10), a high voltage pulse is applied at a cathode voltage control (46) connected between a grid conductor layer (24) and a metal mesh (18) of the FED (10). Upon application of the pulse, the impurities are desorbed from the surface (42) of the microtips (26) and are captured by a getter (44), which binds the impurities to its surface.

Field emission device high voltage pulse system and method

A face plate (10) of an FED image display has a grooved rear surface (25) formed with projections (36). Projections (36) have surfaces (39) covered in regions (58, 59) with electrical conductive material (54) and different color emitting phosphor particles (56a, 56b). The regions (58, 59) define different color anode combs. Surfaces (39) in regions (61) between regions (58,59) are covered with insulative, light absorbing material (62) for absorption of ambient light. Surfaces (39) are formed to encourage forward direction of phosphor-emitted light. In one embodiment, surfaces (39) serve to channel ambient light rearwardly toward projection apexes (40) which are covered with light absorbing material (62). Projections (36) may be parallel elongated prisms, pyramids or cones.

Grooved anode plate for cathodoluminescent display device

Ambient light absorbing face plate for flat panel display

An mode plate 80 for use in a field emission flat panel display device comprises a transparent planar substrate 88 having a plurality of electrically conductive, parallel stripes 50 comprising the anode electrode of the device, which are covered by phosphors 84.sub.R, 84.sub.G and 84.sub.B. The conductors 50 which are covered by the same color phosphors are electrically interconnected by buses 52, 54, and 56. A substantially opaque, electrically insulating material 86 is affixed to substrate 88 in the spaces between conductors 50, acting as a barrier to the passage of ambient light into and out of the device. In addition, the same substantially opaque, electrically insulating material 86 is formed between the conductors 50 and the buses 52, 54, and 56, thereby providing electrical isolation between the two layers. Opaque material 86 preferably comprises glass having impurities dispersed therein, wherein the impurities may include one or more organic dyes, selected to provide relatively uniform opacity over the visible range of the electromagnetic spectrum. Alternatively, the impurities may include the black oxide of a transition metal such as cobalt.

Growing community of inventors

Dallas, TX, United States of America

Jules D Levine