Disclosed are a liquid crystal display device which reduces the number of masks and improves an aperture ratio, and a method for fabricating the same. The liquid crystal display device includes gate and data lines perpendicularly intersecting on a substrate having pixel and pad parts; a thin film transistor on the substrate at the intersection of the gate and data lines; a pixel electrode on the substrate at the pixel part and connected directly to a drain electrode of the thin film transistor; an insulating film on the overall surface of the substrate including the pixel electrode and the thin film transistor; an organic film on the insulating film over the thin film transistor and the data line; and a common electrode of slit shapes overlapping the pixel electrode such that the insulating film is interposed between the common electrode and the pixel electrode.

Liquid crystal display device and method for fabricating the same

Reflection anisotropy spectroscopy (RAS) is a non-destructive optical probe of surfaces that is capable of operation within a wide range of environments. In this review we trace the development of RAS from its origins in the 1980s as a probe of semiconductor surfaces and semiconductor growth through to the present where it is emerging as a powerful addition to the wide range of existing ultra-high vacuum (UHV) surface science techniques. The principles, instrumentation and theoretical considerations of RAS are discussed. The recent progress in the application of RAS to investigate phenomena at metal surfaces is reviewed, and applications in fields including electrochemistry, molecular assembly, liquid crystal device fabrication and remote stress sensing are discussed. We show that the experimental study of relatively simple surfaces combined with continuing progress in the theoretical description of surface optics promises to unlock the full potential of RAS. This provides a firm foundation for the application of the technique to the challenging fields of ambient, high pressure and liquid environments. It is in these environments that RAS has a clear advantage over UHV-based probes for investigating surface phenomena, and its surface sensitivity, ability to monitor macroscopic areas and rapidity of response make it an ideal complement to scanning probe techniques which can also operate in such environments.

http://iopscience.iop.org/article/10.1088/0034-4885/68/6/R01/pdf

Reflection anisotropy spectroscopy

We used near-edge x-ray absorption fine structure (NEXAFS) spectroscopy to link the orientational bond order at three carbonaceous surfaces-rubbed polyimide, ion beam-irradiated polyimide, and ion beam-irradiated diamondlike carbon films-with the direction of liquid crystal (LC) alignment on these surfaces. We show that, in general, LC alignment can be created on any carbonaceous substrate by inducing orientational order at its surface. Our results form the scientific basis for LC alignment layers consisting of amorphous carbon films in which orientational order near the surface is induced by a directional low-energy ion beam.

https://science.sciencemag.org/content/sci/292/5525/2299.full.pdf

Liquid crystal alignment on carbonaceous surfaces with orientational order.

A liquid crystal display device comprises at least two insulating layers formed on a first conductive layer, a second conductive layer formed between the at least two insulating layers, a first contact hole penetrating an upper insulating layer of the at least two insulating layers on the second conductive layer, a second contact hole penetrating the at least two insulating layers and exposing a portion of the first conductive layer, and a contact part comprising a bridge electrode formed of a third conductive layer for connecting the first and second conductive layers through the first and second contact holes. The second contact hole comprises an internal hole penetrating the at least two insulating layers and an external hole surrounding the internal hole forming in the upper insulating layers.

Liquid crystal display device and manufacturing method thereof

Nanocrystalline intermetallic powders have been synthesized from metal salt precursors at low temperatures using a modified polyol process with tetraethylene glycol as the solvent. This solution route has yielded several phase-pure compounds in the M−Sn (M = Ag, Au, Co, Cu, Fe, Ni), Pt−M‘ (M‘ = Bi, Pb, Sb, Sn), and Co−Sb bimetallic systems. In the Co−Sb system, CoSb and CoSb3 can be selectively produced by controlling the initial metal concentrations and the reaction temperature. The Co−Sn and Cu−Sn systems can selectively form Co3Sn2 vs CoSn and Cu6Sn5 vs Cu41Sn11 during a single reaction as a function of temperature. These results demonstrate kinetic control over crystal structure in these intermetallic systems. The reaction progress may be monitored at different times and temperatures by XRD, giving insight into the reaction pathways. TEM micrographs show that the particle sizes in the M−Sn systems range from 5 to 50 nm, while the Pt−M‘ systems range from 10 to 100 nm. SEM micrographs show that these p...

Low-Temperature Solution Synthesis of Nanocrystalline Binary Intermetallic Compounds Using the Polyol Process

The technique used to align liquid crystals—rubbing the surface of a substrate on which a liquid crystal is subsequently deposited1,2,3—has been perfected by the multibillion-dollar liquid-crystal display industry. However, it is widely recognized that a non-contact alignment technique would be highly desirable for future generations of large, high-resolution liquid-crystal displays. A number of alternative alignment techniques have been reported4,5,6,7, but none of these have so far been implemented in large-scale manufacturing. Here, we report a non-contact alignment process, which uses low-energy ion beams impinging at a glancing angle on amorphous inorganic films, such as diamond-like carbon. Using this approach, we have produced both laptop and desktop displays in pilot-line manufacturing, and found that displays of higher quality and reliability could be made at a lower cost than the rubbing technique. The mechanism of alignment is explained by adopting a random network model of atomic arrangement in the inorganic films. Order is induced by exposure to an ion beam because unfavourably oriented rings of atoms are selectively destroyed. The planes of the remaining rings are predominantly parallel to the direction of the ion beam.

Atomic-beam alignment of inorganic materials for liquid-crystal displays

The ability to align liquid crystals to a substrate is a critical step in the liquid crystal display (LCD) manufacturing process with the industry standard technique employing a mechanical rubbing technique to accomplish this function. However, mechanical rubbing can result in debris generation contaminating not only the substrate being processed but also the clean room housing the equipment. As such, post-cleaning of the display panels is required to remove the debris from the surface in addition to the physical isolation of the mechanical rubbing equipment within the clean room environment introducing considerable time and expense. In addition, uneven wear of the mechanical roller during the rubbing process may result in localized defects that will not be observed until final inspection of a completely assembled display. We have developed and introduced into LCD manufacturing a non-contact alignment technique utilizing both diamond-like carbon (DLC) and a low energy ion beam (IB). The replacement of the polyimide alignment layer with DLC results in a completely dry processing technique for both the thin film deposition and alignment steps.

Ion beam alignment for liquid crystal display fabrication

The present invention provides a liquid crystal display device that can eliminate an electrostatic discharge problem resulting from a high dielectric constant filler that is appropriate for improved shape stability of a sealing material. More particularly, the present invention is directed to sealing material 40 disposed between an array substrate 10 and an opposing substrate 12 contains a resin material and an inorganic dielectric filler. The filler consists of talc, mica or alumina having a dielectric constant higher than that of the resin material, and has plate-like or variable shape. The array substrate 10 includes gate lines 26 and data lines 24 that are separated by an insulating layer 28. The gate lines 26 or the data lines 24 that lie on the surface of the insulating layer 28 on the side of the sealing material 40 (e.g., the data lines 24) are led to the surface of the insulating layer 28 opposite the sealing material 40 through vias 62 in the insulating layer 28 and conductive lines 60, before the data lines 24 reach the location of the sealing material 40. Therefore, at the location of the sealing material 40, the data lines 24 are separated from the sealing material 40 by the insulating layer 28, and an electrostatic discharge that occurs through the sealing material 40 can be prevented.

LCD with via connections connecting the data line to a conducting line both before and beyond the sealing material

A method for improving the anchoring of liquid crystals on carbon alignment layers used in liquid crystal displays involves exposing the alignment layer to hydrogen atoms. The atomic hydrogen exposure passivates the surface of the carbon layer to stabilize the anchoring of the subsequently deposited liquid crystals. The substrate on which the carbon layer is supported is located beneath a stretched tungsten filament, and the substrate and filament are located in a vacuum chamber containing hydrogen gas. The heating of the tungsten filament by an appropriate power source dissociates the hydrogen gas into hydrogen atoms and the hydrogen atoms contact the surface of the carbon layer. The process is applicable to stabilize carbon alignment layers that have been formed by directional deposition of carbon, as well as carbon alignment layers where the alignment is caused by a separate ion irradiation step after the carbon layer is formed. As a result of the hydrogen passivation, the liquid crystals subsequently deposited on the passivated carbon alignment layer retain their alignment substantially longer than without the passivation treatment.

Method to stabilize a carbon alignment layer for liquid crystal displays

PROBLEM TO BE SOLVED: To make visual angle characteristics of black brightness in a horizontal oblique direction optimum by achieving a low pretilt angle while holding anchoring energy in an IPS mode by a liquid crystal display panel. SOLUTION: The liquid crystal display panel includes an array substrate overlaid with an alignment layer by covering a polymer layer and a transparent electrode formed on the polymer, and 5 nm or more of surface roughness Ra by roughening the polymer layer overlaying the array substrate and the surface of the alignment layer in the IPS (In-Plane Switching) liquid crystal display panel sealing a liquid crystal layer between the array substrate and a color filter substrate. COPYRIGHT: (C)2006,JPO&NCIPI

Yoshiki Nakagawa

Papers

Atomic-beam alignment of inorganic materials for liquid-crystal displays

Ion beam alignment for liquid crystal display fabrication

LCD with via connections connecting the data line to a conducting line both before and beyond the sealing material

Method to stabilize a carbon alignment layer for liquid crystal displays

Ips liquid crystal display panel