Abstract:
A field emission device (10) is made with a lateral emitter (100) substantially parallel to a substrate (20) and with a simplified anode stucture (70). The lateral-emitter field-emission device has a thin-film emitter cathode (100) which has a thickness not exceeding several hundred angstroms and has an emitting blade edge or tip (110) having a small radius of curvature. The anode's top surface is precisely spaced apart from and below the plane of the lateral emitter and receives electrons emitted by field emission from the blade edge or tip of the lateral-emitter cathode, when a suitable bias voltage is applied. A fabrication process is disclosed using process steps (S1-S18) similar to those of semiconductor integrated circuit fabrication to produce the novel devices and their arrays. Various embodiments of the fabrication process allow the use of conductive or insulating substrates (20) and allow fabrication of devices having various functions and complexity. The anode (70) is simply fabricated, without the use of prior-art processes which formed a spacer made by a conformal coating. In a preferred fabrication process for the simplified anode device, the following steps are performed: an anode film (70) is deposited; an insulator film (90) is deposited over the anode film; an ultra-thin conductive emitter film (100) is deposited over the insulator and patterned; a trench opening (160) is etched through the emitter and insulator, stopping at the anode film, thus forming and automatically aligning an emitting edge of the emitter; and means are provided for applying an electrical bias to the emitter and anode, sufficient to cause field emission of electrons from the emitting edge of the emitter to the anode. The anode film may comprise a phosphor (75) for a device specially adapted for use in a field emission display. The fabrication process may also include steps to deposit additional insulator films (130) and to deposit additional conductive films for control electrodes (140), which are automatically aligned with the emitter blade edge or tip (110).
Abstract:
A lateral field emission device and method of fabricating the device which maximizes gate control of the cathode emitter electric field strength is disclosed. Gate control increases when the position of the gate edge is optimized with respect to the position of the emitter tip. Maximum control is achieved if the gate extends a distance beyond the emitter in the direction of the anode. Preferably, the displacement of the gate edge from the emitter tip is one half the cathode tip-anode distance for optimum control. The high gain device of the present invention provides improved transconductance.
Abstract:
A face plate for a cathode ray tube display is produced by a method in which small holes are formed through a sheet of unfired ceramic tape. The holes are arranged in a desired pattern for the location of pixel dots. The holes are filled with generally transparent glass to form plugs in the desired pattern. The ceramic tape is cured to a hardened state by firing to an appropriate temperature. Each plug is coated at an inner, anode side of the face plate with phosphor of appropriate color.
Abstract:
A flat panel device contains a faceplate, a backplate, a light-emitting mechanism, and a spacer. The faceplate is connected to the backplate to form a sealed enclosure. The spacer is situated within the enclosure and supports the two plates against forces acting towards the enclosure. The spacer can take various forms and can be constituted with various materials. In one embodiment, the spacer includes a spacer wall formed with multiple sheets of laminated material consisting of ceramic, glass-ceramic, ceramic reinforced glass, devitrifying glass, or metal coated with electrical insulation. In another embodiment, the spacer includes a spacer wall having a surface that follows a non-straight path adjacent the faceplate. In yet another embodiment, the spacer is a spacer structure through which a plurality of holes extends. The light-emitting mechanism is typically implemented with an electron-emitting cathode and light-emissive material situated over the faceplate. The cathode may be a thermionic cathode or a field emitter cathode.
Abstract:
The source can be readily aligned and the energy spread of the emitted bean can be controlled to an arbitrarily small value by variation of the voltage. Since no high voltage is present within the emissive part of the electron source, a very compact electron source can be realized.
Abstract:
A method of fabricating a field emission micro-tip which can emit electrons uniformly and can be fabricated at a high yield when applied to a large device. The micro-tip is fabricated such that when the adhesive layer and mask are instantaneously etched the tungsten micro-tips are lifted upwardly due to the differences in internal stress and etching rates of the tungsten cathode, the lower adhesive layer and the upper mask layer. The sharpness of the micro-tip is easily adjusted depending on the shape of the micro-tip. Also, since the internal stress of tungsten and characteristics of the BOE method are utilized throughout the fabricating process, the reproducibility is ensured. Moreover, since multiple tips are fabricated, the output current can be manipulated in a wide range of nanoamperes to milliamperes. Since tungsten is used for fabricating the micro-tips, excellent properties are obtained with regard to strength, oxidation, work function, and electrical, chemical and mechanical durability.
Abstract:
A field emission device (100) having an electron emitter (101), for emitting electrons, an extraction electrode (102) proximally disposed with respect to the electron emitter (101), an anode (103) for collecting some of any emitted electrons is formed. Anode (103) is distally disposed with respect to the electron emitter (101). A transient current source (110) is operably coupled between the electron emitter (101) and a reference potential (107). Transient current source (110) provides a transient current to the electron emitter (101) to enhance response time for emission of electrons from the electron emitter (101) of the field emission device (100). A controlling input line (111) is provided for current controlling signals to the transient current source (110) with the controlling input line (111) being operably coupled to the transient current source (110).
Abstract:
A method is provided for creating gated filament structures for a field emission display. A multi-layer structure is provided that includes a substrate, an insulating layer, a metal gate layer positioned on a top surface of the insulating layer and a gate encapsulation layer positioned on a top surface of the metal gate layer. A plurality of gates are provided and define a plurality of apertures on the top of the insulating layer. A plurality of spacers are formed in the apertures at their edges on the top surface of the insulating layer. The spacers are used as masks for etching the insulating layer and form a plurality of pores in the insulating layer. The pores are plated with a filament material to create a plurality of filaments. The pores can be overplated to create the plurality of filaments. The filaments are vertically self-aligned in the pores.
Abstract:
An electron emitter contains a gate layer (38), an underlying dielectric layer (36), an intermediate non-insulating layer (34) situated below the dielectric layer, and a lower non-insulating region (32) situated below the intermediate non-insulating layer. A multiplicity of electron-emissive particles (42) are situated over the non-insulating region at the bottom of an opening (40) extending through the three layers. The ratio of the thickness of the dielectric layer to the thickness of the intermediate non-insulating layer is in the range of 1:1 to 4:1, while the ratio of the mean diameter of the opening to the thickness of the intermediate non-insulating layer is in the range 1:1 to 10:1. The presence of the intermediate non-insulating layer improves the collimation of the beam of electrons emitted from the electron-emissive elements. The electron emitter is manufactured according to a simple, readily controllable process.
Abstract:
A field emission device (10) has an anode (18) that is used to attract electrons emitter by an emitter (13). An inductor (19) is coupled in series between the anode (18) and a voltage source (21) in order to prevent arcing between the anode (18) and the emitter (13) of the field emission device (10).