JP2013110307A - Semiconductor element mounting package and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that a large-scale and expensive device is required for filling a paste in through holes in a bottomed state when manufacturing a substrate having through hole electrodes.SOLUTION: When a conductive paste is filled in through holes, the paste is filled in the through holes in a through state. By molding a substrate with a thickness thicker than a target thickness and polishing the substrate to the target thickness after hardening of the paste, a dent due to shrinkage of the paste in hardening can be avoided.

Description

  The present invention relates to a package for mounting a semiconductor element having a through electrode and a method for manufacturing the same.

  In recent years, electronic devices have been reduced in size and weight, and electronic components incorporated in electronic devices are also required to be small and light. A package for mounting a semiconductor element having a through electrode can be reduced in size, and is widely used because an electronic device can be reduced in size and weight by mounting electronic components of the electronic device at high density. The through electrode may be filled with a conductive paste inside the electrode (for example, Patent Document 1) or filled with metal by electroplating (for example, Patent Document 2).

  Here, an example of the through electrode that fills the inside of the electrode with the conductive paste in a bottomed state will be described with reference to FIG. In the package substrate composed of the upper substrate 21 and the lower substrate 22, the upper substrate 21 has a through hole 23. Since the upper substrate 21 and the lower substrate 22 are bonded together, the through hole 23 is in a bottomed hole state (FIG. 3A). A plating resist 24 is attached to the upper substrate 21, and a conductive metal 25 (mainly copper or the like) is deposited on the surface by plating (FIGS. 3B and 3C). The conductive paste 26 is filled into the bottomed through hole using a vacuum printing method (FIG. 3D). The plating resist 27 is attached again to deposit the lid plating 28 (FIGS. 3E and 3F). The plated film on the surface including the lid plating is formed into a predetermined pattern by a method such as photo patterning to obtain a package substrate (FIG. 3G).

  In Patent Document 1, since the through electrode is filled with the conductive paste with a bottomed state, a vacuum printing apparatus that is a larger apparatus than a normal printing apparatus is required. In Patent Document 2, since a metal layer is deposited and filled on the through electrode by electroplating, a plating lead for electroplating is required, and there are restrictions on high density and design.

JP 2010-103518 A (page 10, FIG. 5) JP 2008-016819 A (page 9, FIG. 2, FIG. 3)

  Therefore, an object of the present invention is to form and provide a through electrode without using a large-scale apparatus such as a vacuum printing apparatus and without using a plating lead that hinders high density.

  In the semiconductor package manufacturing method according to the present invention, the conductive paste is filled in a through hole state. Since it is not a bottomed state but a through-hole state, the conductive paste can be filled with a normal screen printer without using a vacuum printing apparatus. In addition, when the number of through holes to be filled is small, it is possible to perform filling by dispensing conductive paste into individual through holes by dispensing.

  Most conductive pastes shrink slightly when cured. In order to avoid dents in the through electrode due to curing shrinkage, the thickness of the substrate to be filled with the conductive paste should be thicker than the target thickness, and after filling the conductive paste in the through-hole state, both sides of the substrate should be polished and polished. The surface of the through electrode filled with the conductive paste is flattened while the thickness is set to a desired thickness. Thereafter, it is bonded and bonded to another substrate having electrodes formed on the surface.

  According to the semiconductor package manufacturing method of the present invention, it is possible to form a through electrode without using an expensive and large-scale vacuum printing apparatus.

It is sectional drawing which shows typically the manufacturing method of the package by this invention. It is sectional drawing which shows typically the manufacturing method of the package by this invention. It is sectional drawing which shows the manufacturing method of the conventional package typically.

In the package manufacturing method of the present invention, the paste is filled in the through-hole state when the through-hole is filled with the conductive paste. By forming the substrate thickness to be thicker than the target thickness in advance, and polishing the paste to the target thickness after curing the paste, the dent due to the curing shrinkage of the paste can be eliminated.
Embodiments of the present invention will be described below with reference to the drawings.

  A method for manufacturing a package for mounting a semiconductor element having a through electrode according to this embodiment will be described with reference to FIG. In this embodiment, an example in which glass is used as a substrate material will be described. Fig.1 (a) shows the cross section of the glass substrate 1 used as the base of a board | substrate. As a material of the glass substrate 1, so-called soda glass can be used. Soda glass is also called soda-lime-silica glass, and is characterized by easy molding, excellent chemical durability, easy availability of raw materials, and low cost. Next, in FIG. 1 (b), the glass substrate 1 is softened at a high temperature, and is pressed from above and below with the mold 2. Thus, the glass substrate 1 with the through-hole 3 as shown in FIG.1 (c) is obtained by press-molding the glass substrate 1. FIG. If the shape of the through hole 3 is constricted at the center of the through hole 3 as shown in FIG. 1C, the conductive paste 4 to be filled next is prevented from falling off.

  Here, the thickness of the glass substrate 1 is finished slightly thicker than the target thickness. Next, the conductive paste 4 is filled in the through hole 3. As the conductive paste material, a silver paste in which silver powder is dispersed in a thermosetting resin, a copper paste in which copper powder is dispersed, a paste in which copper powder coated with silver is dispersed, or the like can be used. Alternatively, a baked silver paste in which the resin component is volatilized and almost pure silver remains by baking at a high temperature can be used. As a filling means of the conductive paste 4, in order to take a large number, when the number of through holes 3 in the glass substrate 1 is large, a screen printing method using a metal plate is used. You can select and use the law as appropriate. When the conductive paste 4 filled in the through hole 3 is heat-cured, a dent 5 is usually generated due to curing shrinkage of the conductive paste 4. As shown in FIG. 1E, the conductive paste 4 having the recess 5 is polished together with the glass substrate 1 so as to have a target thickness 6, and the through electrode by the conductive paste 4 as shown in FIG. Thus, the glass lower substrate 7 on which is formed is obtained.

  Next, a method of mounting the semiconductor element 8 on the package will be described with reference to FIG. Here, a light receiving sensor element is used as the semiconductor element 8. A lid plating 9 is formed on the conductive paste 4 of the lower substrate 7 on which the through electrode is formed. Here, the lid plating 9 is electroless plating. Specifically, the palladium catalyst on the glass is washed away by leaving the lower substrate 7 immersed in a solution containing a catalyst mainly containing palladium, and washed appropriately, so that it can remain only on the conductive paste 4. According to a conventional method, electroless nickel plating and electroless gold plating can be performed to form a lid plating composed of a nickel plating layer and a gold plating layer. By using such electroless plating, it is possible to produce the lid plating 9 only on the conductive paste 4 as shown in FIG. 2B without using a method such as photo patterning. The material of the lid plating is not limited to nickel and gold, and metals such as chromium, copper, and silver can also be used.

  Next, the lid side substrate 10 on which the semiconductor element 8 is placed will be described. As shown in FIG. 2C, the lid side substrate 10 has a window 11 in which glass of another material is embedded in the center. An electrode 12 for connecting the semiconductor element 8 is formed on the surface of the lid side substrate 10. As described above, since the semiconductor element 8 is a light receiving sensor element, the light receiving surface 13 sensitive to light exists on the active surface. The semiconductor element 8 is face-down mounted on the electrode 12 on the lid side substrate 10 with the light receiving surface 13 of the semiconductor element 8 aligned with the position facing the window 11. The light receiving surface 13 can be directed to the outside using the glass of the different material as the window 11. As a material for the lid-side substrate 10, it is desirable to use a light-shielding material such as black soda glass in which a black pigment is dispersed in order to avoid stray light on the light receiving surface 13.

  In general, the light receiving surface of a semiconductor element has sensitivity in a wide wavelength range from the infrared region to the ultraviolet region across the visible light region. Various glass materials for the window 11 can be selected depending on the purpose of the light receiving sensor. Visibility can be corrected by embedding green glass (for example, phosphate-based glass) having infrared cut and ultraviolet cut characteristics as the window 11 to provide an illuminance sensor device. An infrared sensor can be formed by embedding glass that transmits the infrared region and cuts the ultraviolet region from the visible region as the window 11, and similarly, an ultraviolet sensor can be formed by embedding the glass that cuts the visible light region from the infrared region as the window 11. .

  The lower glass substrate 7 on which the through electrode is formed and the lid side substrate 10 on which the semiconductor element 8 is mounted face down are bonded together with an adhesive 14. The adhesive 14 is mixed with about 1% to 5% of conductive particles 15. As the adhesive 14, a thermosetting epoxy resin or an ultraviolet curable acrylic resin can be used. Examples of the conductive particles include metal particles such as nickel, copper, and silver, particles obtained by superposing nickel plating and gold plating on resin balls, and particles obtained by applying only nickel plating to resin balls. The particle 15 has a diameter of about 1 μm to 10 μm, preferably about 4 μm to 7 μm. This is because the particles 15 serve as spacers that determine the thickness of the adhesive 14 when cured. If the adhesive layer is too thick or too thin, it is not preferable in terms of strength. The electrode 15 of the lid side substrate 10 and the lid plating 9 of the lower substrate 7 can be electrically connected by the particles 15, and a package 16 on which the semiconductor element 8 is mounted is obtained.

  A package for mounting a semiconductor element having a through electrode can be easily manufactured, which can contribute to reduction in size and weight of an electronic device.

DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Mold 3 Through-hole 4 Conductive paste 7 Glass lower substrate 8 Semiconductor element 9 Lid plating 10 Lid side substrate 11 Window 12 Electrode 13 Light-receiving surface 14 Adhesive 15 Conductive particle 16 Package

Claims (3)

In a semiconductor element mounting package comprising a lid side substrate on which a semiconductor element is mounted and a glass lower substrate bonded to the lid side substrate,
A through-hole having a shape with a constricted central portion penetrating in the thickness direction of the lower glass substrate;
A through electrode made of a conductive paste filled in the through hole;
A plated portion formed on the surface of the through electrode;
An adhesive having conductive particles provided between the lid side substrate and the glass lower substrate;
A package for mounting a semiconductor element, comprising: In a method for manufacturing a semiconductor element mounting package comprising a lid side substrate on which a semiconductor element is mounted and a glass lower substrate bonded to the lid side substrate,
Forming a through hole in the lower glass substrate;
A semiconductor comprising: a step of filling the through hole with a conductive paste; a step of curing the conductive paste; a step of polishing the substrate to a predetermined thickness; and a step of plating on the conductive paste. A method for manufacturing an element mounting package.   3. The method of manufacturing a package for mounting a semiconductor element according to claim 2, wherein the through hole penetrates in the thickness direction of the lower glass substrate and has a constriction at the center.

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