Photomask and its design method

Abstract

The invention discloses a light shield and its designing method. The light shield comprises a transparent part and a lightproof part forming a light shield pattern, the transparent part is partially provided with a diffraction grating structure area adjacent to the edge of the lightproof part, and the grating strip of the diffraction grating structure area parallels to the edge of the adjacent lightproof part. The diffraction grating structure area adjacent to the edge of the lightproof part is designed in the transparent part of the light shield, so the energy of the area exposed to a polyimide film changes, thereby the morphology of the exposed polyimide film is changed, the polyimide film with no tilting can be obtained after heating curing treatment, and an unfavorable influence of tilting on filing solder balls in the subsequent packaging process of an IC circuit is solved.

Description

technical field [0001] The present invention relates to semiconductor manufacturing technology, in particular to a photomask used in lithography at the packaging stage in an IC manufacturing process and a method for designing the photomask. Background technique [0002] In semiconductor manufacturing technology, in the packaging stage of IC (integrated circuit, integrated circuit), a layer of polyimide (polyimide) film is coated on the surface of the substrate containing the chip to protect the substrate; The polyimide film is exposed, developed and heated and cured by etching means, and finally a groove is formed in the required part of the polyimide film to expose the part of the conductive layer in the substrate that needs to be electrically connected to the outside world; then fill the groove with solder balls for electrical connection with the outside world. After the polyimide film is heated and cured, some undesired changes will occur in its morphology, so the existi...

AI Technical Summary

Problems solved by technology

[0006] Because in the subsequent packaging process, solder balls will be filled in the groove 4, the existence of the lift 21 will affect the filling of the solder balls, such as easy to cause voids in the solder balls, affecting the combination of the solder balls and the substrate 1, etc., resulting in Detrimental effects on the subsequent packaging process

Images