JP6459690B2 - Electronic component and manufacturing method thereof - Google Patents

Description

  The present invention relates to an electronic component and a manufacturing method thereof.

  7 to 9 are cross-sectional views for explaining a conventional method of manufacturing an electronic component.

  As shown in FIG. 7A, an Al electrode pad 111 is formed on the semiconductor substrate 101, and a passivation film 112 is formed on the entire surface including the Al electrode pad 111. Next, an opening located on the Al electrode pad 111 is formed in the passivation film 112.

  Next, as shown in FIG. 7B, a photosensitive polyimide film is applied over the semiconductor substrate 101 having the Al electrode pad 111 and the passivation film 112, and is exposed and developed. Thereby, a resin layer 113 made of a polyimide film is formed on the passivation film 112. Next, the resin layer 113 is cured to form resin protrusions (core resin) 102 above the semiconductor substrate 101 as shown in FIG.

  Thereafter, as shown in FIG. 7D, a TiW film 103 is formed on the Al electrode pad 111, the passivation film 112, and the core resin 102 by sputtering. Next, an Au film 107 is formed on the TiW film 103 by sputtering.

  Next, as shown in FIG. 8A, a photoresist film is applied on the Au film 107, exposed and developed, thereby forming a resist pattern 116 on the Au film 107. Next, as shown in FIG. 8B, the Au film 107 is wet etched using the resist pattern 116 as a mask.

  Next, as shown in FIG. 8C, the resist pattern 116 is removed. Next, as shown in FIG. 8D, the wiring layer 114 including the TiW film 103 and the Au film 107 is formed by etching the TiW film 103 using the Au film 107 as a mask. The wiring layer 114 is electrically connected to the Al electrode pad 111 and passes above the core resin 102 (see, for example, Patent Document 1).

  Next, as shown in FIG. 9, a mounting substrate 104 having an electrode (bonded electrode 106) that is bonded to the wiring layer 114 including the TiW film 103 and the Au film 107 passing above the core resin 102 of the semiconductor substrate 101 is prepared. To do. Next, the semiconductor substrate 101 and the mounting substrate 104 are aligned so that the wiring layer 103 on the core resin 102 and the bonded electrode 106 face each other. Next, the Au film 107 of the wiring layer 103 on the core resin 102 is bonded to the bonded electrode 106 by applying a load to the semiconductor substrate 101 and the mounting substrate 104. As a result, the semiconductor substrate 101 is mounted on the mounting substrate 104.

  When the Au film 107 of the wiring layer 114 on the core resin 102 is bonded to the bonded electrode 106, a load is applied to the semiconductor substrate 101 and the mounting substrate 104 to deform the core resin 102 as shown in FIG. At this time, since the end portion 105 of the core resin 102 is greatly deformed, the wiring layer 114 of the end portion 105 must also follow the deformation of the core resin. Since the Au film 107 of the wiring layer 114 is a soft material, it can sufficiently follow the deformation of the end portion 105 of the core resin 102. However, since the TiW film 103 of the wiring layer 114 is a hard material, the TiW film 103 needs to be formed thin in order to follow the deformation of the end portion 105 of the core resin 102.

  When the TiW film 103 is formed thinly, the TiW film 103 sufficiently follows the deformation of the end portion 105 of the core resin 102, so that there is no problem with the bonding on the resin core 102 shown in FIG.

  On the other hand, the wiring layer 114 passing above the core resin 102 is electrically connected to the Al electrode pad 111 as shown in FIG. For this reason, the TiW film 103 also functions as a barrier layer for preventing the Al electrode pad 111 from contacting the Au film 107. However, if the thickness of the TiW film 103 is thin, there arises a problem that it does not function sufficiently as a barrier layer.

  Specifically, the TiW film 103 has a defect, and if the TiW film 103 is thin, Au in the Au film 107 diffuses to the Al electrode pad 111 through the defect and an Au—Al alloy is formed. End up. As the alloy grows, the resistance of the Al electrode pad 111 may increase, or the Al electrode pad 111 may be destroyed at an early stage.

JP2007-12678

  Some aspects of the present invention relate to an electronic component that can function as a barrier of a TiW film even if the thickness of the TiW film on the resin layer is reduced, or a method for manufacturing the same.

  One embodiment of the present invention includes a resin layer located on an insulating film, a TiW film located on the resin layer and the insulating film, a Cu film, an Ag film, a Pd film, and a Pt located on the TiW film. Including any one of a film, a Cr film, a Ni film, and a Ti film, and an Au film positioned on the any one film, wherein the any one film is more than a film thickness of the TiW film. An electronic component characterized by having a thin film thickness.

  According to one embodiment of the present invention, the TiW film can function as a barrier even if the thickness of the TiW film on the resin layer is reduced.

  One embodiment of the present invention is the above-described embodiment of the present invention, wherein the insulating film has an opening, an Al film or an Al alloy film positioned under the opening, and the TiW film includes: The electronic component is electrically connected to the Al film or the Al alloy film through the opening.

  According to one aspect of the present invention, since the Cu film is formed on the TiW film, Cu enters the defect portion of the TiW film, and the Au of the Au film on the Cu film passes through the defect portion of the TiW film. Can hinder. For this reason, even if the thickness of the TiW film on the resin layer is reduced, the function as a barrier of the TiW film can be exhibited.

  Another embodiment of the present invention is the electronic component according to the above embodiment of the present invention, wherein the any one film is etched simultaneously with the Au film or the TiW film. Thereby, a process can be simplified.

One embodiment of the present invention includes a step (a) of forming a resin layer on an insulating film, a step (b) of forming a TiW film on the resin layer and the insulating film, a Cu film on the TiW film, A step (c) of forming any one of an Ag film, a Pd film, a Pt film, a Cr film, a Ni film, and a Ti film; and a step (d) of forming an Au film on the one of the films. Forming a wiring pattern by forming a resist pattern on the Au film, and etching the Au film and any one of the films using the resist pattern as a mask; and peeling the resist pattern And (f) and a step (g) of etching the TiW film using the wiring as a mask.
According to one aspect of the present invention, since the Cu film is formed on the TiW film, Cu enters the defect portion of the TiW film, and the Au of the Au film on the Cu film passes through the defect portion of the TiW film. Can hinder. For this reason, even if the thickness of the TiW film on the resin layer is reduced, the function as a barrier of the TiW film can be exhibited.

  One embodiment of the present invention includes a step (a) of forming a resin layer on an insulating film, a step (b) of forming a TiW film on the resin layer and the insulating film, a Cu film on the TiW film, A step (c) of forming any one of an Ag film, a Pd film, a Pt film, a Cr film, a Ni film, and a Ti film; and a step (d) of forming an Au film on the one of the films. Forming a wiring pattern by forming a resist pattern on the Au film and etching the Au film using the resist pattern as a mask; peeling the resist pattern (f); and wiring A step (g) of etching any one of the films and the TiW film using a mask as a mask.

  According to one aspect of the present invention, since the Cu film is formed on the TiW film, Cu enters the defect portion of the TiW film, and the Au of the Au film on the Cu film passes through the defect portion of the TiW film. Can hinder. For this reason, even if the thickness of the TiW film on the resin layer is reduced, the function as a barrier of the TiW film can be exhibited.

  Another embodiment of the present invention is the above-described embodiment of the present invention, wherein the step of forming an electrode having an Al film or an Al alloy film over the substrate before the step (a), the electrode and the substrate Forming the insulating film on the insulating film, and exposing the electrode through the opening by forming an opening in the insulating film, wherein the step (b) includes the electrode and the resin layer. And a method of manufacturing an electronic component, wherein the TiW film is formed on the insulating film.

FIG. 6 is a plan view illustrating an electronic component according to one embodiment of the present invention. (A) is sectional drawing along the AA line shown in FIG. 1, (B) is sectional drawing along the BB line shown in FIG. (A)-(D) are sectional drawings explaining the manufacturing method of the electronic component shown in FIG.1 and FIG.2. (A)-(D) are sectional drawings explaining the manufacturing method of the electronic component shown in FIG.1 and FIG.2. FIGS. 4A to 4D are cross-sectional views illustrating a method for manufacturing an electronic component according to one embodiment of the present invention. FIGS. FIGS. 4A to 4D are cross-sectional views illustrating a method for manufacturing an electronic component according to one embodiment of the present invention. FIGS. (A)-(D) are sectional drawings for demonstrating the manufacturing method of the conventional electronic component. (A)-(D) are sectional drawings for demonstrating the manufacturing method of the conventional electronic component. Sectional drawing for demonstrating the manufacturing method of the conventional electronic component.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be easily understood by those skilled in the art that modes and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below.

[First Embodiment]
FIG. 1 is a plan view illustrating an electronic component according to one embodiment of the present invention. 2A is a cross-sectional view taken along line AA shown in FIG. 1, and FIG. 2B is a cross-sectional view taken along line BB shown in FIG.

  As shown in FIGS. 1 and 2A and 2B, a semiconductor element 11 (not shown) such as a transistor and wirings (not shown) are formed on a semiconductor substrate 11 as a substrate. The semiconductor substrate 11 may be a semiconductor wafer such as a silicon wafer or a semiconductor chip such as a silicon chip. Moreover, a glass substrate may be used as a substrate, and a ceramic substrate may be used.

  An Al electrode pad 12 is formed on the semiconductor substrate 11. A passivation film (also referred to as an insulating film) 13 is formed on the Al electrode pad 12 and the semiconductor substrate 11, and an opening located on the Al electrode pad 12 is formed in the passivation film 13. Although the electrode pad 12 made of an Al film is used in the present embodiment, an electrode pad made of an Al alloy may be used.

  A core resin (also referred to as a resin layer or a resin protrusion) 14 is formed on the passivation film 13. The core resin 14 is formed in a line shape as shown in FIG.

  A TiW film 22 is formed on the resin protrusion 14, the passivation film 13, and the Al electrode pad 12, and a Cu film 15 is formed on the TiW film 22. An Au film 23 is formed on the Cu film 15. The Au film 23, the Cu film 15 and the TiW film 22 constitute a plurality of wiring layers 24. The wiring layers 24 are electrically connected to the Al electrode pads 12 and pass over the resin protrusions 17 (FIGS. 1 and 2 (A) and (B)).

  The Al electrode pad 12 is in contact with the TiW film 22. Since the Cu film 15 is an auxiliary film for increasing the barrier property of the TiW film 22 by allowing Cu to enter the defect portion of the TiW film 22, the film thickness of the Cu film 15 is smaller than the film thickness of the TiW film 22. May be. In the present embodiment, the Cu film 15 is used as a film for enhancing the barrier property of the TiW film 22, but is not limited to the Cu film, and is not limited to an Ag film, Pd film, Pt film, or Cr film. Any one of a Ni film and a Ti film may be used.

  Next, a method for manufacturing the electronic component shown in FIGS. 1 and 2 will be described with reference to FIGS.

  As shown in FIG. 3A, an Al electrode pad 12 is formed on a semiconductor substrate 11, and a passivation film 13 is formed on the entire surface including the Al electrode pad 12. Next, an opening located on the Al electrode pad 12 is formed in the passivation film 13.

  Next, as shown in FIG. 3B, a photosensitive polyimide film is applied over the semiconductor substrate 11 having the Al electrode pad 12 and the passivation film 13, and is exposed and developed. Thereby, a resin layer 14 a made of a polyimide film is formed on the passivation film 13. The cross-sectional shape of the resin layer 14a is a quadrangle.

  Next, the resin layer 14a is cured to form the core resin 14 above the semiconductor substrate 11 as shown in FIG. The cross-sectional shape of the core resin 14 is a semi-circular shape.

  Thereafter, as shown in FIG. 3D, a TiW film 22a having a thickness of 40 to 100 nm is formed on the Al electrode pad 12, the passivation film 13, and the core resin 14 by sputtering. Next, a Cu film 15a having a thickness of 5 to 50 nm is formed on the TiW film 22a by sputtering. Next, an Au film 23a having a film thickness of 100 to 3000 nm (preferably 200 to 1000 nm) is formed on the Cu film 15a by sputtering.

  Next, as shown in FIG. 4A, a photoresist film is applied on the Au film 23a, and exposed and developed to form a resist pattern 31 on the Au film 23a. Next, as shown in FIG. 4B, the Au film 23a and the Cu film 15a are wet-etched with, for example, a KI solution using the resist pattern 31 as a mask. Since the Cu film 15a is thinner than the TiW film 22a, the Au film 23a and the Cu film 15a can be etched simultaneously. Further, the side etching of the Cu film 15a can be suppressed by making the film thickness of the Cu film 15a thinner than the TiW film 22a.

  Next, as shown in FIG. 4C, the resist pattern 31 is peeled off. Next, as shown in FIG. 4D, the wiring layer 24 including the TiW film 22, the Cu film 15, and the Au film 23 is obtained by wet-etching the TiW film 22a with, for example, hydrogen peroxide water using the Au film 23 as a mask. Form. The wiring layer 24 is electrically connected to the Al electrode pad 12 and passes above the resin protrusion 14.

  Next, a mounting substrate having an electrode (corresponding to the bonded electrode 106 shown in FIG. 9) to be bonded to the wiring layer 24 passing above the resin protrusion 14 of the semiconductor substrate 11 is prepared (not shown). Next, the semiconductor substrate 11 and the mounting substrate (corresponding to the substrate 104 shown in FIG. 9) are aligned so that the wiring layer 24 on the resin protrusion 14 and the bonded electrode face each other. Next, by applying a load to the semiconductor substrate 11 and the mounting substrate, the wiring layer 24 on the resin protrusion 14 is bonded to the electrode to be bonded. Thereby, the semiconductor substrate 11 is mounted on the mounting substrate.

  According to the present embodiment, since the Cu film 15 is formed on the TiW film 22, Cu enters the defect portion of the TiW film 22, and Au of the Au film 23 on the Cu film 15 passes through the defect portion of the TiW film 22. Can prevent you from doing. For this reason, the formation of the Au—Al alloy on the Al electrode pad 12 can be suppressed. As a result, an increase in the resistance of the Al electrode pad 12 due to the Au—Al alloy can be suppressed, and the occurrence of destruction of the Al electrode pad 12 can be suppressed.

  Further, by making the thickness of the Cu film 15a thinner than that of the TiW film 22a, the wiring layer 24 on the resin protrusion 14 is cracked when the wiring layer 24 on the resin protrusion 14 is bonded to the bonded electrode of the mounting substrate. This can be suppressed. Therefore, it is possible to suppress the influence of the crushability of the resin protrusion 14.

  Further, as described above, Cu enters the defect portion of the TiW film 22 and prevents the Au of the Au film 23 on the Cu film 15 from passing through the defect portion of the TiW film 22, thereby increasing the temperature at a high temperature (eg, 400 ° C.) The heat resistance can be improved, and the reliability withstanding long-time use can be secured.

  In addition, since the TiW film 22a, the Cu film 15a, and the Au film 23a are continuously processed by sputtering, the number of processes is not increased compared to the case where the TiW film 22a and the Au film 23a are continuously processed by sputtering.

  By forming the TiW film 22 thin, the amount of side etching when the TiW film 22a is wet etched can be reduced, and the adhesion between the wiring layer 24 and the passivation film 13 can be improved.

[Second Embodiment]
5 and 6 are cross-sectional views for explaining a method of manufacturing an electronic component according to an aspect of the present invention. The same parts as those in FIGS. 3 and 4 are denoted by the same reference numerals, and only different parts are described. To do.

  The processes shown in FIGS. 5A to 5D and 6A are the same as the processes shown in FIGS. 3A to 3D and FIG.

  As shown in FIG. 6B, the Au film 23a is wet-etched with a KI solution, for example, using the resist pattern 31 as a mask.

  Next, as shown in FIG. 6C, the resist pattern 31 is peeled off. Next, as shown in FIG. 6D, the Cu film 15a and the TiW film 22a are wet-etched with, for example, hydrogen peroxide water using the Au film 23 as a mask. Since the Cu film 15a is thinner than the TiW film 22a, the TiW film 22a and the Cu film 15a can be etched simultaneously. Further, the side etching of the Cu film 15a can be suppressed by making the film thickness of the Cu film 15a thinner than the TiW film 22a.

  In this way, the wiring layer 24 including the TiW film 22, the Cu film 15, and the Au film 23 is formed. The wiring layer 24 is electrically connected to the Al electrode pad 12 and passes above the resin protrusion 14.

  In this embodiment, the same effect as that of the first embodiment can be obtained.

  Note that in one embodiment of the present invention, when a specific B (hereinafter referred to as “B”) is formed above (or below) a specific A (hereinafter referred to as “A”) (when B is formed), It is not limited to the case where B is directly formed (or B is formed) on (or below). It includes the case where B is formed (otherwise B) is formed on the upper side (or the lower side) of A through other things as long as the effects of the present invention are not inhibited.

  DESCRIPTION OF SYMBOLS 11 ... Semiconductor substrate, 12 ... Al electrode pad, 13 ... Passivation film (insulating layer), 14 ... Core resin (resin layer, resin protrusion), 14a ... Resin layer, 15, 15a ... Cu film, 22, 22a ... TiW film , 23, 23a ... Au film, 24 ... wiring layer, 31 ... resist pattern, 104 ... mounting substrate, 106 ... electrode to be joined.

Claims (6)

A resin layer located on the insulating film and having resin protrusions ;
A TiW film located on the resin layer and the insulating film;
Any one of a Cu film, an Ag film, a Pd film, a Pt film, a Cr film, a Ni film, and a Ti film located on the TiW film;
An Au film located on any one of the films,
Including
The film thickness of the TiW film is thin so as to follow the deformation of the resin protrusion that is deformed by a load for bonding the electrode to be bonded and the Au film,
The electronic component according to claim 1, wherein the one of the films has a thickness smaller than that of the TiW film. In claim 1,
The insulating film has an opening;
Having an Al film or an Al alloy film located under the opening,
The electronic component, wherein the TiW film is electrically connected to the Al film or the Al alloy film through the opening. In claim 1 or 2,
The thickness of the TiW film is 40 to 100 nm . Forming a resin layer having resin protrusions on the insulating film (a);
A step (b) of forming a TiW film on the resin layer and the insulating film;
A step (c) of forming any one of a Cu film, an Ag film, a Pd film, a Pt film, a Cr film, a Ni film and a Ti film on the TiW film;
A step (d) of forming an Au film on any one of the films;
Forming a resist pattern on the Au film, and forming a wiring by etching the Au film and any one of the films using the resist pattern as a mask; and
A step (f) of removing the resist pattern;
Etching the TiW film using the wiring as a mask (g);
Including
The film thickness of the TiW film is formed to be thin so as to follow the deformation of the resin protrusion deformed by a load for bonding the electrode to be bonded and the Au film,
Any one of the films is formed thinner than the thickness of the TiW film . Forming a resin layer having resin protrusions on the insulating film (a);
A step (b) of forming a TiW film on the resin layer and the insulating film;
A step (c) of forming any one of a Cu film, an Ag film, a Pd film, a Pt film, a Cr film, a Ni film and a Ti film on the TiW film;
A step (d) of forming an Au film on any one of the films;
Forming a wiring pattern by forming a resist pattern on the Au film and etching the Au film using the resist pattern as a mask; and
A step (f) of removing the resist pattern;
Etching the any one film and the TiW film using the wiring as a mask (g);
Including
The film thickness of the TiW film is formed to be thin so as to follow the deformation of the resin protrusion deformed by a load for bonding the electrode to be bonded and the Au film,
Any one of the films is formed thinner than the thickness of the TiW film . In claim 4 or 5,
Before the step (a), a step of forming an electrode having an Al film or an Al alloy film on a substrate, a step of forming the insulating film on the electrode and the substrate, and an opening in the insulating film Forming and exposing the electrode through the opening, and
The step (b) is a step of forming the TiW film on the electrode, the resin layer, and the insulating film.

Images