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AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorsYoshiharu Hirakata, Takeshi Fukada, Shunpei Yamazaki
Estimating the term…
An interlayer insulating film (104) that is formed on a substrate(101) so as to cover TFTs(102, 103) is planarized by mechanical polishing that is typified by CMP. Pixel electrodes (106, 107) are formed on the interlayer insulating film(104) and an insulating layer(108) is formed so as to cover the pixel electrodes. The insulating layer(108) is planarized by second mechanical polishing so that the surfaces of the pixel electrodes become flush with those of resulting buried insulating layers(112, 113). Since the pixel electrode surfaces have no steps, such problems as alignment failures of a liquid crystal material and a contrast reduction due to diffused reflection of light can be prevented.
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Active matrix addressed cells: through-hole connection of the pixel electrode to the active element through an insulation layer
Integrated devices formed in or on insulating or conducting substrates
Characterised by multiple TFTs: interconnections, e.g. scanning lines
Characterised by multiple TFTs: characterised by the compositions or shapes of the interlayer dielectrics
Term ended 22 Mar 2018 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
1. Field of the Invention
The present invention relates to a manufacturing method of a liquid crystal display device (LCD), in particular, an active matrix liquid crystal display device (hereinafter abbreviated as AM-LCD) that uses a semiconductor thin film. The invention can be applied to an electro-optical device having such a display device.
2. Description of the Related Art
FIGS. 1A to 1C are sectional views for brief description of the present invention;
FIGS. 2A and 2B show the configuration of a conventional pixel matrix circuit;
FIGS. 3A to 3D and 4A to 4C show a process of manufacturing a reflection-type LCD according to a first embodiment of the invention;
First, the present invention will be described briefly with reference to FIGS. 1A to 1C and 10A to 10C.
In FIG. 1A, reference numeral 101 denotes a substrate having an insulating substrate, and numerals 102 and 103 denote first and second pixel TFTs, respectively, formed on the substrate 101. The first and second pixel TFTs 102, 103 are covered with an interlayer insulating film 104, which is an insulating film for electrically insulating the pixel TFTs 102 and 103 from pixel electrodes that will be formed later.
A first feature of a first aspect of the invention is that the interlayer insulating film 104 that has been deposited so as to be thicker than a necessary thickness is subjected to a planarization step (particularly by mechanical polishing). The interlayer insulating film 104 polishing step, which will be described later, will play an important role in forming pixel electrodes later. In FIG. 1A, a broken line 105 represents the shape of the interlayer insulating film 104 before being subjected to the polishing step and indicates that surface asperities of the interlayer insulating film 104 are removed, i.e., the surface is planarized, by the mechanical polishing step.