Transflective liquid crystal device and method of manufacturing the same
AssigneeThe Hong Kong University of Science and Technology
InventorsZhiguo Meng, Man Wong, Hoi Sing Kwok
Life of this patent
Estimating the term…
Abstract
The construction of electrodes for liquid-crystal displays using larger grain lower absorption (LGLA) poly-Si showing an absorptivity below 20% in the visible light region is described. Integration in the manufacturing of substrates for active-matrix LCDs is shown. Source, drain and channel region (108b, 108c, 108d) of the TFTs as well as the pixel-electrode (108e) are formed conjointly in a single poly-Si layer.
Claims30
A transflective liquid crystal display device comprising:
- a. a first substrate;
- b. a second substrate arranged facing said first substrate with a gap therebetween;
- c. a liquid crystal layer sandwiched in the gap between the first and second substrates;
- d. a partially doped semiconductive poly-Si layer formed on said first substrate, in which a pixel electrode and a portion of a TFT are formed;
- e. a mirror for performing display using reflected light;
- wherein said pixel electrode is electrically connected to said portion of the TFT and wherein said poly-Si has a grain size of 0.5-1000 μm, an average absorptivity of light of 5-20% in the visible light region, and a sheet resistance of 0.01-1 KΩ/square.
A transflective liquid crystal display device comprising
- a. a first substrate, a second substrate comprising and a liquid crystal layer provided between inner surfaces of the first and the second substrates,
- b. a plurality of pixel regions and a plurality of switching elements on the first substrate, each of the pixel regions comprising a reflective region and a transmissive region, wherein the transmissive region comprises a transmissive electrode formed at a location corresponding to the transmissive region of each pixel region, and the reflective region comprises
- i. a mirror for performing display using reflected light;
- ii. a metal electrode;
- iii. pixels of red, green, and blue colors, wherein pixel color is controlled by adjusting the area of the mirror;
- wherein the metal electrode is electrically connected to the switching element and wherein said transmissive electrode includes poly-Si, said poly-Si having a grain size of 0.5-1000 μm, an average absorptivity of 20% or lower, and a sheet resistance of 0.01-1 KΩ/square.
A process of making a transflective liquid crystal device, comprising:
- a. providing a first substrate;
- b. depositing an amorphous silicon layer on the substrate;
- c. forming a poly-Si layer from said amorphous silicon layer, said poly-Si having a grain size of about 0.5-1000 μm, an average absorptivity of 20% or lower in the visible light region and a sheet resistance of 0.01-1 KΩ/square;
- d. partially doping the poly-Si layer, forming a doped region and an un-doped region;
- e. forming a portion of a TFT and a pixel electrode in the doped region of the poly-Si layer;
- f. forming a second substrate arranged facing the first substrate with a gap therebetween;
- g. forming a liquid crystal layer in the gap between the first and second substrate.
A transflective liquid crystal display device made by
- a. forming a partially doped poly-Si layer on a first substrate, said poly-Si having a grain size of about 0.5-1000 μm, a sheet resistance of 0.01-1 KΩ/square and an average absorptivity of 20% or lower in the visible light region;
- b. forming an electrode region of a TFT and a pixel electrode in the partially doped poly-Si layer;
- c. forming a second substrate arranged facing the first substrate with a gap therebetween;
- d. forming a liquid crystal layer in the gap between the first and second substrate.
Dependencies are inferred from the claim text.