阅读说明：本技术 一种新型电镀法制作大锡球方法 (method for making big tin ball by new electroplating method ) 是由 郁发新 冯光建 王志宇 陈华 张兵 于 2019-09-27 设计创作，主要内容包括：本发明公开了一种新型电镀法制作大锡球方法,具体包括如下步骤：101)辅助层制作步骤、102)曝光步骤、103)电镀步骤、104)大锡球制作步骤；本发明提供双层胶曝光的方式制作的一种新型电镀法制作大锡球方法。(The invention discloses a method for manufacturing large solder balls by novel electroplating methods, which comprises the following steps of 101) manufacturing an auxiliary layer, 102) exposing, 103) electroplating and 104) manufacturing the large solder balls, and provides a method for manufacturing novel electroplating methods by exposing double-layer glue.)

1, novel electroplating method for manufacturing big tin balls, which is characterized in that the method comprises the following steps:

101) the manufacturing method of the auxiliary layer comprises the steps of manufacturing a seed layer on the upper surface of a carrier plate through a physical sputtering, magnetron sputtering or evaporation process, manufacturing an th photoresist layer above the seed layer, wherein the thickness of the th photoresist layer ranges from 1um to 100um, the manufacturing method adopts a spin coating process or a spraying process, and manufacturing a second photoresist layer above the th photoresist layer to form the auxiliary layer, wherein the manufacturing method and the thickness of the second photoresist layer are the same as those of the th photoresist layer;

102) an exposure step: exposing the auxiliary layer through an exposure process, and then exposing only the second photoresist layer through a second exposure process;

103) electroplating, namely removing th photoresist layers and the second photoresist layers of the exposed auxiliary layer by a developing process to expose the electroplated metal position of the interconnection pad, and depositing electroplated metal, wherein the metal adopts or a mixture of titanium, copper, aluminum, silver, palladium, gold, thallium, tin and nickel, and the metal deposition adopts a layer or multilayer structure;

104) the big tin ball manufacturing step: removing the auxiliary layer by wet etching or dry etching process, and removing the seed layer by wet etching process; and coating the soldering flux on the upper surface of the carrier plate, and cleaning the soldering flux through reflow soldering to obtain the large solder balls.

2. The new electroplating method for making big solder balls as claimed in claim 1, wherein the seed layer has a thickness of 1nm to 100 μm, and a -layer or multi-layer structure, and is made of or more of Ti, Cu, Al, Ag, Pd, Au, Tl, Sn, and Ni.

Technical Field

The invention relates to the technical field of semiconductors, in particular to a method for manufacturing a large tin ball by novel electroplating methods.

Background

Wafer level packaging technology is the most technologies used in advanced packaging field, especially for consumer products, wafer level packaging is widely applied to mobile electronic devices and micro-functional devices by due to its advantages of small size, light weight, thin thickness, etc.

The wafer level packaging uses solder balls or metal bumps like the external solder interconnection , the manufacturing process of the solder balls comprises direct ball planting, solder ball manufacturing by using solder paste and solder ball manufacturing by electroplating, the bumps comprise metal column planting and metal bump electroplating, however, in the process of manufacturing the solder balls by electroplating, the height of the electroplated tin is influenced by the thickness of the photoresist layer, if a larger solder ball needs to be manufactured, very thick solder tin needs to be electroplated, the existing photoetching gluing process is difficult to realize, if the electroplating area is increased, the amount of the electroplated tin can be increased, but the base of the solder ball is increased, and the solder ball still cannot be too large.

Disclosure of Invention

The invention overcomes the defects of the prior art and provides novel methods for manufacturing the big solder ball by using the electroplating method.

The technical scheme of the invention is as follows:

method for making big tin ball by new electroplating method, which comprises the following steps:

101) the manufacturing method of the auxiliary layer comprises the steps of manufacturing a seed layer on the upper surface of a carrier plate through a physical sputtering, magnetron sputtering or evaporation process, manufacturing an th photoresist layer above the seed layer, wherein the thickness of the th photoresist layer ranges from 1um to 100um, the manufacturing method adopts a spin coating process or a spraying process, and manufacturing a second photoresist layer above the th photoresist layer to form the auxiliary layer, wherein the manufacturing method and the thickness of the second photoresist layer are the same as those of the th photoresist layer;

102) an exposure step: exposing the auxiliary layer through an exposure process, and then exposing only the second photoresist layer through a second exposure process;

103) electroplating, namely removing th photoresist layers and the second photoresist layers of the exposed auxiliary layer by a developing process to expose the electroplated metal position of the interconnection pad, and depositing electroplated metal, wherein the metal adopts or a mixture of titanium, copper, aluminum, silver, palladium, gold, thallium, tin and nickel, and the metal deposition adopts a layer or multilayer structure;

104) the big tin ball manufacturing step: removing the auxiliary layer by wet etching or dry etching process, and removing the seed layer by wet etching process; and coating the soldering flux on the upper surface of the carrier plate, and cleaning the soldering flux through reflow soldering to obtain the large solder balls.

, the seed layer has a thickness of 1nm to 100um, and has a structure of layers or multi-layer structure, and is made of or more of titanium, copper, aluminum, silver, palladium, gold, thallium, tin and nickel.

Compared with the prior art, the invention has the advantages that: the invention manufactures large-area electroplating soldering tin on a smaller base in a double-layer glue exposure mode, and then obtains a larger solder ball through reflux.

Drawings

FIG. 1 is a schematic view of a carrier layer of the present invention;

FIG. 2 is a schematic view of FIG. 1 with an th photoresist layer;

FIG. 3 is a schematic view of FIG. 2 after exposure of a second photoresist layer disposed thereon in accordance with the present invention;

FIG. 4 is a schematic view of the metallization of FIG. 3 of the present invention;

FIG. 5 is a schematic view of FIG. 4 with the th photoresist layer removed and the second photoresist layer removed in accordance with the present invention;

FIG. 6 is a schematic view of the seed layer removal of FIG. 5 according to the present invention;

FIG. 7 is a schematic view of the present invention;

FIG. 8 is a schematic view of a seed layer and an th photoresist layer disposed on a carrier according to the present invention;

FIG. 9 is a schematic representation of the th exposure area of FIG. 8 requiring exposure in accordance with the present invention;

FIG. 10 is a schematic view of FIG. 9 with a second photoresist layer disposed and showing the desired exposure area in accordance with the present invention;

FIG. 11 is a schematic view of the invention in FIG. 10 with photoresist applied.

The carrier 101, the seed layer 102, the th photoresist layer 103, the second photoresist layer 104, the bonding pad 105, the plated metal 106, the large solder ball 107, the th exposure region 108, and the second exposure region 109 are marked in the figure.

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, wherein like or similar reference numerals refer to like or similar elements or elements of similar function throughout. The embodiments described below with reference to the drawings are exemplary only, and are not intended as limitations on the present invention.

It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein by .

Reference numerals in the various embodiments are provided for steps of the description only and are not necessarily associated in a substantially sequential manner. Different steps in each embodiment can be combined in different sequences, so that the purpose of the invention is achieved.

The invention is further described in conjunction with the figures and the detailed description.