JP2005101468A - Semiconductor device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor element where bubbles are reduced in a bump, and to provide its manufacturing method. <P>SOLUTION: The method for manufacturing a semiconductor element comprises a first step for preparing a semiconductor substrate 1 having a barrier metal layer 3 and a print mask 6 having an elongated opening 7, and a second step for arranging a print mask 6 on the semiconductor substrate 1 such that the opening 7 is located on the barrier metal layer 3. When the print mask 6 is arranged on the semiconductor substrate 1 in the second step, one end of the opening 7 in the longitudinal direction is located on the barrier metal layer 3 and the other end in the longitudinal direction is located outside the barrier metal layer 3. Furthermore, the distance L<SB>1</SB>between the other end of the opening 7 in the longitudinal direction and the end of the barrier metal layer most separated therefrom, and an effective radius r on the upper surface of the barrier metal layer is set to satisfy a relation 3.5×r≤L<SB>1</SB>. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a semiconductor element that is electrically connected to a circuit pattern on a circuit board via a bump, and a method for manufacturing the same.

  Conventionally, a semiconductor element is face-down bonded to the upper surface of a circuit board having a circuit pattern, that is, the semiconductor element is mounted on the circuit board with the integrated circuit formation surface of the semiconductor element facing the circuit board. Things have been done.

  A semiconductor element used for such face-down bonding is called a flip-chip type IC and generally has a terminal connected to a circuit pattern on a circuit board via a conductive material such as solder.

  As such a conventional flip chip type IC, as shown in FIG. 4, solder is applied on a plurality of barrier metal layers 13 made of nickel or the like deposited on one main surface of a semiconductor substrate 11 provided with an integrated circuit. A structure in which bumps 15 are selectively formed is known.

  When mounting such a flip chip type IC on a circuit board, the flip chip type IC is placed on the circuit board so that the solder bumps of the flip chip type IC face the corresponding circuit pattern on the circuit board, Thereafter, the solder bump is heated and melted at a high temperature, whereby the barrier metal layer of the flip chip IC is soldered to the circuit pattern on the circuit board.

The above-described flip chip type IC is usually manufactured by a technique as shown in FIG. That is,
(1) A semiconductor substrate 11 having a plurality of barrier metal layers 13 and a passivation layer 14 deposited on a region where the barrier metal layer 3 is not formed on the upper surface, and a plurality of one-to-one correspondences with the barrier metal layer 13 A printing mask 16 having an opening 17 is prepared (FIG. 5A);
(2) Next, the printing mask 16 is arranged on the semiconductor substrate 11 so that the opening 17 of the printing mask 16 is located on the barrier metal layer 13 (FIG. 5B).
(3) Subsequently, the solder paste 15′a supplied onto the printing mask 16 is printed and applied onto the barrier metal layer 13 through the opening 17 using a squeegee or the like (FIG. 5C).
(4) Finally, the applied solder paste 15 'is heated to form spherical solder bumps 15, and the semiconductor substrate 11 is processed into a predetermined shape, thereby completing a flip-chip IC (FIG. 5D). .

Note that the opening 17 provided in the above-described printing mask 16 has an elongated hole shape that is slightly larger than the barrier metal layer 13, and the printing mask 16 is placed on the semiconductor substrate 11 so as to surround the barrier metal layer 13 by the opening 17. In addition, the lower surface of the printing mask 16 is in contact with the surface of the passivation layer on the semiconductor substrate 11.
JP-A-6-267964

  However, when the print mask 16 is arranged on the semiconductor substrate 11 in this way, there is no gap between the semiconductor substrate 11 (passivation layer 14) and the print mask 16, so the solder paste 15 'is filled in the opening 17. At this time, the air in the opening 17 has no escape, and the air is caught in the solder paste 15 ′. When such solder paste 15 ′ is heated to form solder bumps 15 on the barrier metal layer 13, a flip chip IC in which many bubbles are mixed inside the solder bumps 15 is obtained. When this flip-chip type IC is mounted on a circuit board, the wettability between the melted solder bump 15 and the circuit pattern on the circuit board is deteriorated due to bubbles in the solder bump 15, and the bonding strength between them is reduced. Triggers problems that degrade.

  The present invention has been devised in view of the above problems, and an object of the present invention is to provide a semiconductor device with few bubbles contained in bumps and a method for manufacturing the same.

The semiconductor element manufacturing method of the present invention includes a first step of preparing a semiconductor substrate having a plurality of barrier metal layers on an upper surface and a printing mask having an elongated hole-like opening corresponding to the barrier metal layer; A second step of disposing a print mask on the semiconductor substrate such that the opening is positioned on the barrier metal layer; and supplying a paste on the print mask, and supplying the supplied paste through the opening to the barrier In the method for manufacturing a semiconductor device, comprising: a third step of applying on the metal layer; and a fourth step of heating the applied paste to form bumps on the barrier metal layer. When the printing mask is arranged on the semiconductor substrate, one end in the longitudinal direction of the opening is positioned on the barrier metal layer, and the other end in the longitudinal direction of the opening is positioned outside the barrier metal layer. Both the distance L ₁ between the longitudinal end portion and the barrier metal layer end farthest to the other end portion of the _opening, the relationship between the effective radius r of the barrier metal layer upper surface, wherein (1) 3.5 × characterized by being set so as to satisfy r ≦ L _1.

Further, in the method for manufacturing a semiconductor element of the present invention, in the above-described manufacturing method, in the second step, the distance L ₂ between the one end in the longitudinal direction of the opening and the end of the barrier metal layer, the upper surface of the barrier metal layer The relation of the effective radius r is set so as to satisfy the formula (2) 0.5 × r ≦ L ₂ ≦ 1.4 × r.

  Furthermore, the semiconductor element manufacturing method of the present invention is characterized in that, in the above-described manufacturing method, a chamfered portion is formed at a corner on the lower surface side of the printing mask located at one end in the longitudinal direction of the opening.

  On the other hand, the semiconductor device of the present invention is a semiconductor device in which a plurality of barrier metal layers are scattered on a semiconductor substrate, and bumps are formed on the barrier metal layers. The number of bubbles having a diameter of 1/5 or more of the effective radius r on the upper surface of the metal layer is an average of 1 / bump or less.

According to the present invention, when the printing mask is disposed on the semiconductor substrate, one longitudinal end of the opening of the printing mask is positioned on the barrier metal layer, and the other longitudinal end of the opening is outside the barrier metal layer. And the relationship between the distance L ₁ between the other end in the longitudinal direction of the opening and the end of the barrier metal layer farthest from the other end and the effective radius r of the upper surface of the barrier metal layer is expressed by Equation (1) 3 Since the paste was applied on the barrier metal layer through the opening in a state where the print mask was arranged on the semiconductor substrate so as to satisfy .5 × r ≦ L ₁ , a part of the applied paste was It will protrude greatly outside the barrier metal layer. Therefore, when the applied paste is heated in forming the bumps on the barrier metal layer, the paste that protrudes outside the barrier metal layer largely flows toward the barrier metal layer, and bubbles contained in the paste during the flow. Will be discharged out of the paste. As a result, the number of bubbles in the bump formed on the barrier metal layer can be reduced, and when the semiconductor element is mounted on the circuit board, the wettability between the melted bump and the circuit pattern on the circuit board is reduced. It becomes favorable and the joint strength between both can be made high.

  In addition, according to the present invention, since one end in the longitudinal direction of the opening is positioned on the barrier metal layer, a gap is formed between the print mask around the opening and the semiconductor substrate, and the paste is placed in the opening. When filling, the gap becomes an escape place for air in the opening, and the air is discharged from between the printing mask and the semiconductor substrate through the gap. Therefore, the number of bubbles mixed in the paste when applying the paste can be reduced, and this can also increase the bonding strength between the circuit board and the semiconductor element.

According to the invention, the relationship between the distance L ₂ between the longitudinal end of the opening and the end of the barrier metal layer and the effective radius r of the upper surface of the barrier metal layer is expressed by the equation (2) 0.5 × r ≦ L By setting to satisfy ₂ ≦ 1.4 × r, the paste applied on the barrier metal layer without protruding from the barrier metal layer can be slightly fluidized when heating the paste, A bump having a small number of bubbles can be provided.

  Furthermore, according to the present invention, a chamfered portion is formed at a lower surface side corner portion of the printing mask located at one end portion in the longitudinal direction of the opening so that the lower surface of the one end portion in the longitudinal direction of the opening contacts the barrier metal layer. Therefore, it is possible to prevent the surface of the barrier metal layer from being damaged and to maintain high wettability of the barrier metal layer with respect to the paste constituting the bump, thereby increasing the adhesion strength between the bump and the barrier metal layer. It becomes possible to raise.

  Furthermore, according to the present invention, the number of bubbles having a diameter of 1/5 or more of the effective radius r of the upper surface of the barrier metal layer existing in the bump is set to an average of 1 / bump or less. When mounting on the board, it is possible to effectively prevent the problem that bubbles gather near the joint surface between the bump and the circuit board and the joint strength between the two is insufficient.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view of a flip chip type IC shown as an example of a semiconductor element of the present invention. The flip chip type IC shown in FIG. 1 is roughly a semiconductor substrate 1, a circuit wiring 2, a barrier metal layer 3, and a passivation. It consists of a layer 4 and bumps 5.

  The semiconductor substrate 1 is made of a semiconductor material such as single crystal silicon, and a functional element (not shown) such as a transistor, a circuit wiring 2, a barrier metal layer 3, a passivation layer 4 and the like are deposited on the upper surface thereof, It functions as a support base material that supports these.

  Such a semiconductor substrate 1 is obtained by, for example, slicing a single crystal silicon ingot formed by a conventionally known chocolate ski method (pull-up method) or the like to a predetermined thickness, and polishing the surface thereof. Thereafter, an insulating film is formed on the entire surface of the plate body by a conventionally known thermal oxidation method.

  The circuit wiring 2 formed on the semiconductor substrate 1 is deposited to a thickness of 0.5 μm to 1.5 μm with a metal material such as aluminum or copper. It functions as a power supply wiring for supplying signals and the like.

  A pad region 2 a is provided on a part of the upper surface of the circuit wiring 2, and a plurality of barrier metal layers 3 are formed on the pad region 2 a.

  The barrier metal layer 3 is formed of a constituent material of the bump 5 described later and a material having good wettability. For example, when the bump 5 is formed of solder, the barrier metal layer 3 is mainly composed of nickel (Ni). For example, a structure in which zinc (Zn), Ni and gold (Au) are sequentially stacked from the semiconductor substrate 1 side, a structure in which Zn and Ni are sequentially stacked, a structure in which Ni and Au are sequentially stacked, palladium (Pd ), A configuration in which Ni and Au are sequentially stacked, a configuration in which Pd and Ni are sequentially stacked, and a configuration in which Ni and Au are sequentially stacked are employed.

  The barrier metal layer 3 effectively prevents the aluminum or the like forming the circuit wiring 2 from being eroded with the melting of the bump 5 provided on the barrier metal layer 3 when the flip chip type IC is mounted on the circuit board. It works to prevent it.

  The circuit wiring 2 including the pad region 2a described above is formed in a predetermined pattern on the upper surface of the semiconductor substrate 1 by employing conventionally known sputtering, photolithography technology, and etching technology. Further, the barrier metal layer 3 is formed by, for example, adopting a conventionally known electroless plating method or the like to the pad region 2a exposed from the passivation layer 4 described later, so that the constituent material of the barrier metal layer 3 is changed from the semiconductor substrate side. The layers are sequentially laminated to form a cylindrical shape with a thickness of 1 μm to 4 μm. As a result, the upper surface of the barrier metal layer 3 is usually higher than the surface of the passivation layer 4 described later.

On the other hand, a passivation layer 4 made of an electrically insulating material such as silicon nitride (Si ₃ N ₄ ), silicon oxide (SiO ₂ ), or polyimide is provided in the non-formation region of the barrier metal layer 3 with circuit wiring 2 or a functional element (not shown). It is applied to cover.

  A part of the passivation layer 4 extends to a part of the upper surface of the pad region 2 a of the circuit wiring 2, and the surface of the passivation layer 4 swells upward in the extended part as compared with other regions. It becomes.

  Such a passivation layer 4 effectively blocks the circuit wiring 2 and the barrier metal layer from being corroded from the atmosphere, thereby effectively corroding the functional element and the circuit wiring 2 due to contact with moisture contained in the atmosphere. It works to prevent it.

  The passivation layer 4 is formed to a thickness of 0.5 μm to 3.0 μm on the upper surface of the semiconductor substrate 1 by employing a conventionally known sputtering, photolithography technique, etching technique or the like.

  A spherical bump 5 is formed on the upper surface of the barrier metal layer 3 described above, and the bump 5 is formed of a conductive material such as solder. For example, when the bump 5 is made of solder, an alloy for metal bonding in which tin (Sn), silver (Ag), and copper (Cu) are melted and solidified at a predetermined ratio is generally used.

  The bump 5 acts to bond the barrier metal layer 3 of the flip chip IC and the circuit pattern on the circuit board by being heated and melted when the flip chip IC is mounted on the circuit board.

  Since the number of bubbles having a diameter of 1/5 or more of the effective radius r of the upper surface of the barrier metal layer contained in the bump 5 is very small as an average of 1 piece / bump or less, the bump chip IC is formed on the circuit board. When mounted on top, the wettability between the melted bump 5 and the circuit pattern on the circuit board becomes good. Therefore, it is possible to provide a flip chip IC capable of increasing the bonding strength between the flip chip IC and the circuit board.

  Note that the effective radius r of the upper surface of the barrier metal layer refers to the radius when the planar shape of the upper surface of the barrier metal layer is circular. Further, when the planar shape of the upper surface of the barrier metal layer is a shape other than a circle, it means the radius of a virtual circle having an area equal to the area of the upper surface of the barrier metal layer.

  Thus, the flip chip type IC described above is placed on the circuit board such that the plurality of bumps 5 face the corresponding circuit patterns on the circuit board, and then the bumps 5 are heated and melted at a high temperature, The molten bump 5 is mounted on the circuit board by bonding it to a circuit pattern or the like on the circuit board. At this time, since there are almost no large bubbles in the bumps, the bonding strength between the flip chip type IC and the circuit board can be increased.

  Next, a method for forming the above-described flip chip type IC will be described with reference to FIG. This figure is a cross-sectional view for explaining a method of manufacturing the flip chip type IC of FIG.

  Step (1): First, a semiconductor substrate 1 having a circuit wiring 2, a barrier metal layer 3, and a passivation layer 4 deposited on the upper surface, and a printing mask 6 are prepared (FIG. 2A).

  The printing mask 6 has a structure in which a plurality of openings 7 having a long hole shape are formed in a mask body formed in a plate shape by a metal material such as an aluminum alloy or a Ni alloy. The placed paste 5 ′ is applied on the barrier metal layer 3 through the opening 7. The printing mask 6 is formed by adopting a conventionally known additive method when the mask body is made of Ni alloy. Further, the shape of the opening 7 may be a long hole shape such as an oval shape, a rectangular shape, or a parallelogram shape.

  Step (2): Next, a print mask 6 is disposed on the semiconductor substrate 1 (FIG. 2B).

At this time, the printing mask 6 is disposed so as to contact the passivation layer 4 on the semiconductor substrate 1, one end in the longitudinal direction of the opening 7 is disposed on the barrier metal layer 3, and the other end in the longitudinal direction of the opening 7. The portion is disposed on the semiconductor substrate 1 so as to be farther away than the barrier metal layer 3. Specifically, the relationship between the distance L ₁ between the other end in the longitudinal direction of the opening 7 and the end of the barrier metal layer farthest from the other end and the effective radius r of the upper surface of the barrier metal layer is expressed by Equation (1) 3 .5 × r ≦ L ₁ is important, so that when the paste 5 ′ is applied onto the barrier metal layer 3 in a later step, a part of the paste 5 ′ is applied to the barrier metal. It is possible to greatly protrude outside the layer 3, and it is possible to increase the flow of the paste 5 ′ when the paste 5 ′ is heated to reduce the number of bubbles contained in the bumps 5. The effective radius r on the upper surface of the barrier metal layer is as described above.

  In addition, since one end in the longitudinal direction of the opening 7 is located on the barrier metal layer 3, the print mask 6 around the opening 7 is partially above the upper surface by the barrier metal layer 3 whose height of the upper surface is higher than that of the passivation layer 4. Thus, a gap G is formed between the lower surface of the printing mask 6 around the opening and the surface of the passivation layer on the semiconductor substrate 1. Therefore, when the paste 5 ′ is filled in the opening 7 in a later step, the gap G becomes an escape area for the air in the opening 7, and the air passes through the gap G and the print mask 6 and the semiconductor substrate 1 (passivation). It will be discharged from between the layers 4). Therefore, the number of bubbles mixed in the paste 5 'when applying the paste 5' can be reduced, and this can also be used to maintain the bonding strength between the circuit board and the flip chip type IC.

The distance between the distance L ₁ and the relation between the effective radius r addition to satisfying the above formula (1), as in the present embodiment, one end portion in the longitudinal direction with the above-described barrier metal layer end of the opening 7 L _2, by setting the relationship between the effective radius r of the barrier metal layer upper surface of the above so as to satisfy _{0.5 × r ≦ L 2 ≦ 1.4} × r, without protruding from the barrier metal layer 3 In addition, the paste 5 ′ applied on the barrier metal layer 3 can also be made to flow slightly when the paste 5 ′ is heated, whereby the bump 5 having a smaller number of bubbles can be obtained.

If the relationship between the distance L ₁ and the effective radius r is 3.5 × r> L ₁ , the flow distance of the applied paste 5 ′ is too short, and bubbles in the paste 5 ′ can be removed. It becomes difficult. Therefore, it is important to set the relationship between the distance L ₁ and the effective radius r to 3.5 × r ≦ L ₁ .

If the relationship between the distance L ₂ and the effective radius r is L ₂ <0.5 × r, the flow distance of the paste 5 ′ applied on the barrier metal layer 3 is short, so the bubbles of the paste 5 ′ On the other hand, if L ₂ > 1.4 × r, the amount of paste 5 ′ applied on the barrier metal layer 3 is too small, and the paste 5 ′ is heated. There is a possibility that the paste 5 ′ protruding outside the barrier metal layer 3 cannot flow to the barrier metal layer 3. Therefore, it is preferable to set the relationship between the distance L ₂ and the effective radius r so as to satisfy 0.5 × r ≦ L ₂ ≦ 1.4 × r.

  Step (3): Subsequently, the paste 5 ′ is supplied onto the printing mask, and the squeegee is moved in a state where the blade edge of the squeegee is pressed against the printing mask 6, and the paste 5 ′ is moved to the opening 7 of the printing mask 6. Then, it is applied on the barrier metal layer 3 (FIG. 2C).

  At this time, since the positional relationship between the opening 7 and the barrier metal layer 3 is set so as to satisfy the above formula (1), a part of the paste 5 ′ applied on the barrier metal layer 3 is part of the barrier metal layer. 3 will protrude greatly to the outside of 3.

  Note that a conductive material is used as the paste 5 '. For example, a solder paste or the like that is adjusted to a predetermined viscosity by adding and mixing a flux or the like to a large number of solder particles is preferably used.

  Step (4): Finally, the paste 5 ′ applied on the barrier metal layer 3 is dried, and then heated at a temperature of 220 ° C. to 260 ° C. for 20 seconds to 3 minutes, so that the barrier metal layer 3 is heated. Bumps 5 are formed on the substrate (FIG. 2D).

  When the paste 5 ′ is heated, the paste 5 ′ that protrudes outside the barrier metal layer 3 flows greatly toward the barrier metal layer 3, and bubbles contained in the paste 5 ′ are discharged outside the paste 5 ′ during the flow. Will be. As a result, the number of bubbles in the bump 5 formed on the barrier metal layer 3 can be reduced, and when the flip chip IC is mounted on the circuit board, the melted bump and the circuit pattern on the circuit board The wettability is improved, and the bonding strength between them can be increased.

  In addition, this invention is not limited to the above-mentioned embodiment, A various change and improvement are possible in the range which does not deviate from the summary of this invention.

  For example, in the above-described embodiment, if a chamfered portion 7 a such as an R surface or a C surface is formed at the lower surface side corner portion of the printing mask 6 positioned at one end portion in the longitudinal direction of the opening 7, one end portion in the longitudinal direction of the opening 7. Can be satisfactorily prevented from being damaged by contact with the barrier metal layer 3, whereby the wettability of the barrier metal layer 3 with respect to the paste 5 ′ constituting the bump 5 can be maintained high. The reliability of bonding between the bump 5 and the barrier metal layer 3 can be increased.

Next, the function and effect of the present invention will be described based on examples. In this embodiment, when a paste is applied on a plurality of barrier metal layers provided on a semiconductor substrate using a printing mask and heated to form bumps on the barrier metal layer, the longitudinal direction of the opening described above is applied. with different relation between the effective radius r of the distance L ₁ and the barrier metal layer upper surface of the other end portion and the barrier metal layer end little by little, in the case of forming a bump for each of these relationships, a barrier contained per bump The number of bubbles having a diameter of 1/5 or more of the effective radius r on the upper surface of the metal layer was measured.

The number of bubbles in the bump was measured by a microfocus X-ray inspection apparatus (X-ray transmission method). The opening is an oblong hole formed by combining a semicircular hole with a radius of 37 μm at both ends of a rectangular hole having a dimension of 50 μm × 74 μm, and the longitudinal direction of the opening. The width is 124 μm, and the width in the short direction is 74 μm. The barrier metal layer has a cylindrical shape whose upper surface is a circle having a radius of 3.5 μm (effective radius of 3.5 μm). As the paste, a solder paste in which Sn: Ag: Cu was mixed at a weight ratio of 96.5: 3.0: 0.5 was used, and the paste heating temperature when forming the bumps was 245 ° C. The number of barrier metal layers, that is, the number of bumps, was 30. The above results are shown in Table 1.

According to Table 1, sample No. _{1 in} which the relationship between the distance L ₁ between the other end in the longitudinal direction of the opening and the end of the barrier metal layer and the effective radius r of the upper surface of the barrier metal layer satisfies 3.5 × r ≦ L ₁ . 4-No. In 7, the number of bubbles is reduced. On the other hand, Sample No. is not satisfied 3.5 × r ≦ _{L 1} 1-No. In No. 3, the number of bubbles in the bump is increased.

From the above implementation results, in order to obtain the effect of the present invention, the relationship between the distance L ₁ between the other end in the longitudinal direction of the opening and the end of the barrier metal layer and the effective radius r of the barrier metal layer is 3.5 × r. It can be seen that it is sufficient if ≦ L ₁ is satisfied.

It is sectional drawing of the flip chip type IC as an example of the semiconductor element of this invention. (A)-(d) is sectional drawing for demonstrating the manufacturing method of the flip chip type IC of FIG. It is a top view of the opening of the printing mask used for an Example. It is sectional drawing of the flip chip type IC as an example of the conventional semiconductor element. (A)-(d) is sectional drawing for demonstrating the manufacturing method of the flip chip type IC of FIG.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate 2 ... Circuit wiring 2a ... Pad area | region 3 ... Barrier metal layer 4 ... Passivation layer 5 ... Bump 5 '... Paste 6 ... Printing mask 7 ..Opening

Claims (4)

A first step of preparing a semiconductor substrate having a plurality of barrier metal layers on an upper surface and a printing mask having an elongated hole-like opening corresponding to the barrier metal layer, and the opening is located on the barrier metal layer A second step of arranging the print mask on the semiconductor substrate, and a third step of supplying the paste on the print mask and applying the supplied paste onto the barrier metal layer through the opening. And a fourth step of heating the applied paste to form bumps on the barrier metal layer,
When the printing mask is disposed on the semiconductor substrate in the second step, one end in the longitudinal direction of the opening is positioned on the barrier metal layer, and the other end in the longitudinal direction of the opening is outside the barrier metal layer. The relationship between the distance L ₁ between the other end in the longitudinal direction of the opening and the end of the barrier metal layer farthest from the other end and the effective radius r of the upper surface of the barrier metal layer is expressed by the following equation (1). A method of manufacturing a semiconductor device, characterized in that the semiconductor device is set to satisfy.
Equation (1): 3.5 × r ≦ L 1 In the second step, the relationship between the distance L ₂ between one end of the opening in the longitudinal direction and the end of the barrier metal layer and the effective radius r of the upper surface of the barrier metal layer was set so as to satisfy Expression (2). The method of manufacturing a semiconductor device according to claim 1.
Formula (2): 0.5 × r ≦ L ₂ ≦ 1.4 × r The method for manufacturing a semiconductor device according to claim 1, wherein a chamfered portion is formed at a corner portion on the lower surface side of the printing mask located at one end portion in the longitudinal direction of the opening. In a semiconductor element formed by interposing a plurality of barrier metal layers on a semiconductor substrate and forming bumps on the barrier metal layer,
The number of bubbles having a diameter of 1/5 or more of the effective radius r of the upper surface of the barrier metal layer among the bubbles present in the bump is 1 on average / bump or less.

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