Method for producing grey mask and grey mask

Abstract

An object of the present invention is to provide a method for manufacturing a gray tone mask in halftone film type being capable of manufacturing TFT in high quality. The present invention relates to a method for manufacturing gray tone mask having a light-shielding part, a transparent part, and a translucent part, comprising the steps of preparing a mask blank having a translucent film (22) and a light-shielding film (23) sequentially formed on a transparent substrate (21), forming a resist pattern (24a) of an area corresponding to the light-shielding part onto the mask blank and forming a light-shielding part onto the translucent film (22) by etching light-shielding film (23) with said resist pattern (24a) as a mask, and forming resist pattern (24b) onto an area at least comprising the translucent part, and subsequently forming the translucent part and transparent part by etching translucent film (22) with the said resist pattern (24b) as a mask.

Description

technical field [0001] The present invention relates to a method of manufacturing a graytone mask and a graytone mask suitable for use in the manufacture of thin film transistor liquid crystal displays (Thin Film Transistor Liquid Crystal Display: hereinafter referred to as TFT-LCD) and the like. Background technique [0002] Patent Document 1: JP-A-2000-111958 [0003] Non-Patent Document 1: "Monthly Magazine EFPIDI INTELLIGENCE (FPD·Intelligence)", May 1999, p.31-35. [0004] Since TFT-LCDs have the advantages of being thinner and having lower power consumption than CRTs (cathode ray tubes), their commercialization is currently progressing rapidly. TFT-LCD has a TFT substrate in which TFTs are arranged in each pixel arranged in a matrix, and has a color filter in which red, green, and blue pixel patterns are arranged corresponding to each pixel and overlapped with a liquid crystal phase. rough structure. TFT-LCD has many manufacturing processes, and only the TFT substra...

AI Technical Summary

Problems solved by technology

[0013] However, according to such a conventional mask manufacturing method, pattern drawing is performed separately in the photolithography step of forming the light-transmitting part for the first time and the photolithography step of forming the semi-transparent part in the second time. In order to avoid pattern deviation between the second drawing and the first drawing, in practice, even if the alignment accuracy is improved, it is difficult to completely eliminate the alignment deviation

For example, if Figure 14 As shown in (a), due to misalignment, when the semi-transparent portion pattern 203 is formed offset along the illustrated X direction, the area of ​​the light shielding portion corresponding to the source / drain of the TFT substrate is different from the design value , there will be a problem that the TFT characteristics will change

In addition, if Figure 14 As shown in (b), due to misalignment, when the semi-transparent portion pattern 203 is formed offset in the Y direction shown in the figure, problems will arise due to a short circuit between the source / drain of the TFT substrate.

In short, in such a conventional mask manufacturing method, it is very difficult to form the channel part which is particularly important in TFTs with high precision.

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