JPS6357942B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a semiconductor device, and mainly relates to a method of manufacturing a tape carrier type integrated circuit, and is particularly effective in stabilizing the shape of metal protruding electrodes and improving manufacturing yield. The present invention relates to a manufacturing method that exhibits the following characteristics.

Generally, a pattern is formed using a first photoresist, using this as a mask, metal wiring is formed by first plating, a pattern for protruding electrodes is formed using a second photoresist, the plating solution is removed by washing with water, and then the plating solution is removed. In the conventional semiconductor device manufacturing method of forming metal protruding electrodes by plating the second plating solution, the residue of the first plating solution is incorporated into the uneven portions of the plating surface and is not sufficiently removed before the second plating solution is applied. photoresist, exposed and
Since development processing and the like are performed, deformation of the photoresist pattern is likely to occur during development. That is,
The presence of plating solution residue at the interface between the first plating surface and the photoresist reduces the adhesion of the photoresist to the plating surface, promoting swelling of the photoresist during development and causing pattern movement. . The modification of the above photoresist pattern is the second
This deforms the shape of the metal protrusion electrode formed by the plating and reduces the adhesion between the lead wire and the metal protrusion electrode, which has a serious adverse effect on the reliability of the semiconductor device.

As a method of preventing such deformation of the photoresist pattern, there is a method of cleaning the substrate by immersing it in pure water excited by ultrasonic waves before applying the second photoresist to reduce the plating solution residue, or a method of reducing the plating solution residue. Conventionally, a method has been used in which the degree of polymerization of the photoresist is improved by increasing the ultraviolet irradiation time during the formation of the photoresist pattern, as described in 2, thereby reducing the swelling of the photoresist. However, the former method is not sufficiently effective in reducing the plating solution residue and there remains a risk of deformation of the photoresist pattern, while the latter method has various drawbacks such as a significant decrease in productivity.

The present invention eliminates the above-mentioned drawbacks and provides a method for forming metal protruding electrodes with a high yield while preventing deformation of a photoresist pattern. According to the present invention, no pattern deformation of the second photoresist occurs, and therefore no deformation occurs in the shape of the metal protrusion electrode formed using the photoresist as a mask.

That is, the feature of the present invention is that the first
forming a first photoresist pattern using the first photoresist pattern as a mask, forming a gold layer wiring by first gold plating, and then cleaning the semiconductor substrate by immersing it in pure water. a step of removing the first photoresist by a plasma ashing method after drying; a step of spraying a xylene solvent onto the surface of the semiconductor substrate while rotating the semiconductor substrate; and a step of drying the substrate. forming a second photoresist pattern, and then performing second gold plating using the second photoresist pattern as a mask, thereby forming a gold protrusion electrode on the wiring of the gold layer. A method of manufacturing a semiconductor device having the following features.

Next, the present invention will be explained by examples. 1 to 6 are cross-sectional views in the case where the present invention is applied to the formation of gold-plated wiring and gold protrusion electrodes of a tape carrier type integrated circuit. In FIG. 1, a platinum wiring pattern 2 patterned by an etching method or a lift-off method is provided on a semiconductor substrate 1 on which elements have already been formed by a general method. A first photoresist is deposited on this substrate and patterned into a desired shape by a conventional method to form a photoresist pattern 3 (FIG. 2). After this,
The substrate is immersed in a gold plating solution, and a current is passed between the substrate and the plating solution to perform plating 4 to a desired thickness (FIG. 3). Next, the substrate is washed by immersing it in pure water, and after drying, the first photoresist 3 is removed by plasma ashing (FIG. 4). Here, a thin residue 41 of the plating solution that cannot be removed by the cleaning described above remains on the gold plating surface, and if the second photoresist is applied as it is and patterning is performed, the photoresist and the gold plating surface will be separated due to the presence of the residue. The adhesion with the pattern deteriorates and the pattern becomes deformed.

Therefore, in the present invention, the surface of the substrate is cleaned with an organic solution prior to depositing the second photoresist. That is, a solvent such as xylene is sprayed on the substrate while it is being rotated, and then it is dried. As a result, the plating solution residue 41 on the first gold plating 4 is completely removed. Thereafter, a second photoresist is applied and exposed and developed to form a desired photoresist pattern. Thereafter, gold plating is performed on the substrate in a conventional manner to form gold protruding electrodes 6 (FIG. 5), and further, by removing all of the photoresist, gold wiring and gold protruding electrodes of the desired shape are formed. (Figure 6).

As described above, according to the present invention, a semiconductor device having plated wiring and plated electrodes can be manufactured with high yield and productivity.

[Brief explanation of the drawing]

FIGS. 1 to 6 are cross-sectional views showing embodiments of the present invention in the order of manufacturing steps. In the figure, 1...a semiconductor substrate on which elements have been formed, 2...a substrate 1 formed by a lift-off method, etc.
Upper platinum wiring pattern, 3... First photoresist patterned into desired shape, 4... First plating, 41... Residue of plating solution remaining on first plating, 5... Desired. A second photoresist patterned in the shape of 6... is a gold protrusion electrode formed by second plating.

Claims (1)

[Claims] 1. A step of forming a wiring pattern of a metal film on a semiconductor substrate, a step of forming a first photoresist pattern on the semiconductor substrate so that the wiring pattern of the metal film is exposed, and the first photoresist pattern. A step of forming a gold layer wiring on the wiring pattern of the metal film by first gold plating using as a mask, and then cleaning the semiconductor substrate by immersing it in pure water, drying it, and then applying a plasma ashing method. a step of removing the first photoresist pattern, a step of spraying a xylene solvent onto the surface of the semiconductor substrate while rotating the semiconductor substrate, and then drying it; and then performing second gold plating using the second photoresist pattern as a mask, thereby forming a gold protrusion electrode on the wiring of the gold layer. manufacturing method.