Semiconductor device and method of manufacturing the same
AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorsYoshiharu Hirakata, Shunpei Yamazaki
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AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorsYoshiharu Hirakata, Shunpei Yamazaki
Estimating the term…
To provide an active matrix type liquid crystal display device having fine display performance, an interlayer insulating film 104 covering TFTs 102, 103 formed on a substrate 101 is first flattened by mechanical polishing typified by a CMP. Then pixel electrodes 106, 107 are formed thereon, and further, an insulating layer 108 covering the pixel electrodes is formed. And then, the insulating layer 108 is flattened by second mechanical polishing so that the surfaces of the pixel electrodes and the surface of the insulating layers 112, 113 form the same plane. By this, a difference in level disappears, and it is possible to prevent lowering of contrast or the like due to poor orientation of a liquid crystal material, diffused reflection of light, and the like.
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A semiconductor device comprising:
A display device comprising:
A display device comprising:
A display device comprising:
A semiconductor device comprising:
Dependencies are inferred from the claim text.
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Liquid crystal cells structurally associated with a semi-conducting layer or substrate, e.g. cells forming part of an integrated circuit: active…
Active matrix addressed cells: light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally…
Active matrix addressed cells: through-hole connection of the pixel electrode to the active element through an insulation layer
Constructional arrangements; Manufacturing methods: planarisation layers
Term end not estimated
1. Field of the Invention
The present invention relates to a method of manufacturing a liquid crystal display device (LCD), and particularly to a method of manufacturing an active matrix type liquid crystal display device using a semiconductor thin film (hereinafter referred to as an AM-LCD). The present invention can be applied to an electrooptical device equipped with such a display device.
Incidentally, in the present specification, the term “semiconductor device” indicates all devices which function by using a semiconductor. Thus, the foregoing display device and the electrooptical device are included in the category of the semiconductor device. However, in the present specification, for facilitation of the distinction, terms such as a display device and an electrooptical device are selectively used.
In the accompanying drawings:
FIGS. 1A to 1C are views for explaining the outline of the present invention;
FIGS. 2A and 2B are views showing the structure of a conventional pixel matrix circuit;
First, the outline of the present invention will be described with reference to FIGS. 1A to 1C. In FIG. 1A, reference numeral 101 denotes a substrate having an insulating surface, 102 denotes a first pixel TFT formed on the substrate 101, and 103 denotes a second pixel TFT. The first and second TFTs 102 and 103 are covered with an interlayer insulating film 104. The interlayer insulating film 104 is an insulating film for electrically insulating pixel electrodes formed later from the TFTs.
The first feature of the present invention is that the interlayer insulating film 104 having a sufficient thickness is deposited in advance, and a flattening step (especially flattening by mechanical polishing) is carried out. As described later, the polishing step of the interlayer insulating film 104 plays an important role when a pixel electrode is subsequently formed. In FIG. 1A, a dotted line denoted by 105 indicates the shape of the interlayer insulating film 104 prior to the polishing step, and this indicates that the unevenness of the interlayer insulating film 104 is flattened by the mechanical polishing step.
It is important to carry out this flattening so that the remaining unevenness becomes not larger than 10% of the thickness of the pixel electrode.