JP2744740B2 - Semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device which forms a hybrid integrated circuit by mounting a flip chip on a circuit board.

[0002]

2. Description of the Related Art FIG. 5 is a cross-sectional view showing an example of a conventional semiconductor device. In FIG. 5, reference numeral 1 denotes a flip chip, 2 denotes a flip-chip 1 and a circuit board on which other electronic components (not shown) are mounted. The ceramic substrate 3 is a plastic cylindrical protection ring surrounding the flip chip 1 and mounted on the ceramic substrate 2, 4 is a silicon gel as a gel injected and filled in the protection ring 3, 5 is the flip chip 1 And an exterior resin for exteriorly mounting the entire ceramic substrate 2 on which a hybrid integrated circuit is mounted with other electronic components mounted thereon.

In order to assemble a conventional semiconductor device configured as described above, first, electronic components such as a resistor and a capacitor and a flip chip 1 of 3 mm square, for example, are mounted on a ceramic substrate 2 on which a desired wiring pattern is formed. Thus, a hybrid integrated circuit is formed. Next, a diameter of 5 to 6 is set on the ceramic substrate 2 so as to surround the flip chip 1.
The protective ring 3 having a cylindrical shape having a thickness of 0.5 mm, a thickness of 0.5 mm, and a height of 2 mm is attached. Further, silicon gel 4 is injected into the protection ring 3 and filled so that the flip chip 1 is buried. Thereafter, the ceramic substrate 2 on which the hybrid integrated circuit is formed is immersed in an exterior resin solution, for example, an epoxy-based resin solution, to cover the entire surface of the ceramic substrate 2 and the mounted components with the exterior resin 5.

In the above-described conventional semiconductor device, since the cylindrical protection ring 3 is attached so as to surround the flip chip 1 mounted on the ceramic substrate 2, external force is not directly applied to the flip chip 1, The breakage of the flip chip 1 is prevented. Further, since the protective ring 3 is filled with the silicon gel 4, the penetration of moisture into the flip chip 1 is prevented, and the moisture resistance of the flip chip 1 is improved. Furthermore, since the entire surface of the ceramic substrate 2 and the mounted components is covered with the exterior resin 5, the moisture resistance of the entire hybrid integrated circuit is improved and the reliability is improved.

[0005]

As described above, in the conventional semiconductor device, the cylindrical protective ring 3 is mounted on the ceramic substrate 2, and after the protective ring 3 is filled with the silicon gel 4, the exterior resin 5 is removed. Because of the coating, in a heat cycle test in which a high temperature state and a low temperature state are repeated, a thermal stress generated due to a difference in thermal expansion coefficient between the ceramic substrate 2 and the protection ring 3 causes a boundary between the ceramic substrate 2 and the protection ring 3. In other words, the resin concentrates on the lower end of the outer periphery of the protective ring 3, cracks occur in the outer resin 5 at the lower end of the outer periphery of the protective ring 3, and the silicon gel 4 and the lithicon gel 5 There is a problem that cracks occur in the exterior resin 5 on the top 4, the moisture resistance is reduced, and the reliability is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a semiconductor device capable of suppressing the occurrence of cracks in an exterior resin due to a change in temperature, improving moisture resistance and improving reliability. The purpose is to gain.

[0007]

According to a first aspect of the present invention, there is provided a semiconductor device including a flip chip mounted on a circuit board, a protective ring surrounding the flip chip and having an upper opening on the circuit board. In a semiconductor device which is mounted and filled with a gel in a protective ring and packaged with a package resin, an outer peripheral surface of the protective ring is formed so as to be inclined such that its outer diameter is reduced from a lower end surface toward an upper end surface. In addition, the upper opening of the protection ring is closed by a ring cover.

Further, in a semiconductor device according to a second aspect of the present invention, a flip chip is mounted on a circuit board, a protection ring surrounding the flip chip and having an upper opening is mounted on the circuit board, and the protection ring is provided. In a semiconductor device which is filled with a gel and packaged with a package resin, an outer peripheral surface of the protective ring is formed into a curved surface so that an outer diameter thereof is reduced from a lower end surface toward an upper end surface, and the protective ring is formed. Is closed with a ring cover.

Further, in a semiconductor device according to a third aspect of the present invention, a flip chip is mounted on a circuit board, a protective cover is mounted around the flip chip, and a gel is filled in the protective cover . In a semiconductor device packaged with a package resin, the protective cover has a hollow hemispherical shape, and a gel injection hole and an air vent hole are formed in the protective cover .

In a semiconductor device according to a fourth aspect of the present invention, a flip chip is mounted on a circuit board, and the protection ring surrounds the flip chip and has an upper opening on the circuit board. In a semiconductor device comprising a protective ring, a gel filled in the protective ring, and a package with a package resin, a protective cover having a smooth curved outer peripheral surface is placed on the circuit board so as to surround and store the protective ring. It is to be attached to.

[0011]

According to the first aspect of the present invention, since the outer peripheral surface of the protection ring is formed so as to be inclined so that the outer diameter thereof is reduced from the lower end surface toward the upper end surface, the circuit board is subjected to a temperature change. The concentration of thermal stress caused by the difference in the coefficient of thermal expansion between the protection ring and the protection ring at the lower end of the outer periphery of the protection ring is reduced, and the occurrence of cracks in the exterior resin at the lower end of the outer periphery of the protection ring is suppressed. In addition, since the upper opening of the protection ring is closed by the ring cover, the protection ring and the ring cover completely surround the flip chip, preventing the flip chip from being damaged by external force, and furthermore, the outer resin is placed on the gel. Is not covered, and there is no occurrence of cracks in the exterior resin on the gel, which has conventionally occurred due to a temperature change.

In a second aspect of the present invention,
Since the outer peripheral surface of the protection ring is formed into a curved surface such that its outer diameter decreases from the lower end surface toward the upper end surface, the outer peripheral surface of the protective ring is caused by a difference in coefficient of thermal expansion between the circuit board and the protective ring due to a temperature change. The generated thermal stress is reduced over the entire outer periphery of the protection ring, and the occurrence of cracks in the exterior resin is suppressed over the entire outer periphery of the protection ring. In addition, since the upper opening of the protection ring is closed by the ring cover, the protection ring and the ring cover completely surround the flip chip, preventing the flip chip from being damaged by external force, and furthermore, the outer resin is placed on the gel. Is not covered, and there is no occurrence of cracks in the exterior resin on the gel, which has conventionally occurred due to a temperature change.

In a third aspect of the present invention,
Since the protective cover is a hollow hemispherical shape, is relaxed throughout the outer periphery of the thermal stress protective cover caused by the difference in thermal expansion coefficient between the circuit board and the protective cover as the temperature changes, the exterior throughout the protective cover outer periphery Generation of cracks in the resin is suppressed. In addition, the flip chip is completely surrounded, preventing the flip chip from being damaged by external force, and furthermore, the outer resin is not coated on the gel. There is no occurrence.

[0014] In a fourth aspect of the present invention,
Since the outer peripheral surface of the protective ring is surrounded by a protective cover having a smooth curved surface and accommodated, the thermal stress generated due to the difference in the coefficient of thermal expansion between the circuit board and the protective cover due to the temperature change is reduced. It is alleviated over the entire outer periphery of the protection ring, and the occurrence of cracks in the exterior resin is suppressed over the entire outer periphery of the protection ring.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. Embodiment 1 FIG. Embodiment 1 is an embodiment according to the first invention of the present invention. FIG. 1 is a cross-sectional view of a semiconductor device showing a first embodiment of the present invention. In the drawing, the same or corresponding parts as those of the conventional semiconductor device shown in FIG.

In the drawing, reference numeral 6 denotes a protection ring. The protection ring 6 has, for example, a lower end having an outer diameter of 6 mm, an upper end having an outer diameter of 5 mm, an inner peripheral diameter of 4.5 mm, and a height of 2 mm. The outer peripheral surface is formed in a cylindrical shape in which the outer diameter is inclined such that the outer diameter decreases from the lower end surface toward the upper end surface. Reference numeral 7 denotes a ring cover for closing the upper opening of the protection ring 6, and reference numeral 8 denotes an air layer generated between the silicon gel 4 filled in the protection ring 6 and the ring cover 7.

In order to assemble the semiconductor device configured as described above, first, electronic components such as a resistor and a capacitor and a flip chip 1 of, for example, 3 mm square are mounted on a ceramic substrate 2 on which a desired wiring pattern is formed. Construct a hybrid integrated circuit. Next, a protection ring 6 is attached on the ceramic substrate 2 so as to surround the flip chip 1. Next, the silicon gel 4 is injected into the protection ring 6 and filled so that the flip chip 1 is buried. Further, the upper opening of the protection ring 6 is closed by the ring cover 7. At this time, an air layer 8 is formed in a gap between the silicon gel 4 and the ring cover 7. Thereafter, the ceramic substrate 2 on which the hybrid integrated circuit is formed is immersed in an exterior resin solution, for example, an epoxy-based resin solution, to cover the entire surface of the ceramic substrate 2 and the mounted components with the exterior resin 5.

According to the first embodiment, since the outer peripheral surface of the protection ring 6 is inclined from the lower end surface toward the upper end surface,
Concentration of the thermal stress caused by the difference in the coefficient of thermal expansion between the ceramic substrate 2 and the protection ring 6 due to the temperature change at the boundary between the ceramic substrate 2 and the protection ring 6 is reduced, and the exterior resin at the boundary is reduced. 5 is suppressed. Further, since the upper opening of the protection ring 6 is closed by the ring cover 7, the exterior resin 5 is not directly covered on the silicon gel 4, and is generated in the conventional semiconductor device shown in FIG. The occurrence of cracks in the exterior resin 5 on the silicon gel 4 due to the temperature change is prevented.

Accordingly, the occurrence of cracks in the exterior resin 5 due to repeated temperature changes in the high temperature state and the low temperature state is suppressed, the moisture resistance of the exterior resin 5 is improved, and the reliability can be improved.

The protection ring 6 and the ring cover 7
Since the flip chip 1 is completely surrounded by
External force is not directly applied to the flip chip 1, and the flip chip 1 can be protected with high strength from damage due to external force.

Embodiment 2 FIG. Embodiment 2 is an embodiment according to the second invention of the present invention. FIG. 2 is a cross-sectional view of a semiconductor device according to a second embodiment of the present invention. In the figure, reference numeral 9 denotes a protection ring. The protection ring 9 has, for example, an outer diameter of 6 mm at a lower end, 5 mm at an upper end, and 4.5 inner circumference
mm, the height is 2 mm, and the outer peripheral surface is formed into a curved surface such that the outer diameter decreases from the lower end surface toward the upper end surface. Reference numeral 10 denotes a ring cover for closing the upper opening of the protection ring 9.

In the second embodiment, the outer peripheral surface of the protection ring 9 is formed as a curved surface so that the outer diameter decreases from the lower end surface toward the upper end surface, so that the ceramic substrate 2 and the protection ring 9 Is reduced not only at the boundary between the ceramic substrate 2 and the protection ring 9 but also over the entire outer periphery of the protection ring 9 , so that not only the boundary but also the protection ring 9 is reduced. Cracking of the exterior resin 5 is suppressed over the entire outer peripheral surface.
Further, the upper opening of the protection ring 9 is closed by the ring cover 10 to prevent the exterior resin 5 from being covered on the silicon gel 4 and to prevent external force from being directly applied to the flip chip 1.

Therefore, according to the second embodiment, the occurrence of cracks in the entire exterior resin 5 due to the temperature change is suppressed, the moisture resistance of the exterior resin 5 is improved, and the reliability can be improved. Thus, the flip chip 1 can be protected with high strength from being damaged by an external force.

Embodiment 3 FIG. Embodiment 3 is an embodiment according to the third invention of the present invention. FIG. 3 is a cross-sectional view of a semiconductor device showing a third embodiment of the present invention. In the figure, reference numeral 11 denotes a protective cover . The protective cover 11 has, for example, an outer diameter of 6 mm and an inner diameter of 5 mm.
mm. 12 is a protective cover 11
An air vent hole 13 is formed in the protective cover 11, and a gel injection hole 13 is formed in the protective cover 11.

In the third embodiment, a protective cover is provided so as to surround the flip chip 1 mounted on the ceramic substrate 2.
-11 and attach the silicone gel 4 through the gel injection hole 13.
After the injection, the exterior resin 5 is covered. The other configuration is the same as that of the first embodiment.

According to the third embodiment, the exterior resin 5 is not covered on the silicon gel 4 and the protective cover 11
Has a smooth curved surface, which suppresses the occurrence of cracks in the entire exterior resin 5, improves the moisture resistance of the exterior resin 5, improves reliability, and allows external force to be directly applied to the flip chip 1. Without being applied, the flip chip 1 can be protected with high strength from damage due to external force.

Embodiment 4 FIG. Embodiment 4 is an embodiment according to the fourth invention of the present invention. FIG. 4 is a sectional view of a semiconductor device according to a fourth embodiment of the present invention.
Is a protective cover, and the protective cover 14 is mounted on the ceramic substrate 2 so as to house the entire protective ring 3.

According to the fourth embodiment thus constructed, since the outer peripheral surface of the protective cover 14 has a smooth curved surface, the coefficient of thermal expansion between the ceramic substrate 2 and the protective cover 14 with a change in temperature is increased. The thermal stress generated due to the difference between the two is alleviated over the entire outer periphery of the protective cover 14, the occurrence of cracks in the exterior resin 5 is suppressed, and the moisture resistance of the exterior resin 5 is improved.
Reliability can be improved. Further, the flip chip 1 can be protected with high strength from damage due to external force.

Further, since the protective cover 14 is covered, the structure of the conventional protective ring 3 can be changed from the conventional protective ring 3 to the protective ring in each of the above embodiments for the purpose of improving reliability. Can be effectively utilized.

[0030]

Since the present invention is configured as described above, it has the following effects.

According to the first aspect of the present invention, a flip chip is mounted on a circuit board, a protection ring surrounding the flip chip and having an upper opening is mounted on the circuit board, and gel is placed in the protection ring. In a semiconductor device that is filled and packaged with a package resin, an outer peripheral surface of a protective ring is formed so as to be inclined so that an outer diameter thereof is reduced from a lower end surface toward an upper end surface, and an upper opening of the protective ring is formed. Since the part is closed by the ring cover, the occurrence of cracks in the exterior resin at the boundary between the circuit board and the protection ring and at the interface between the exterior resin and the gel is suppressed, the moisture resistance of the exterior resin can be improved, and reliability can be improved. Performance can be improved and the flip chip can be prevented from being damaged by external force.

According to the second aspect of the present invention, a flip chip is mounted on a circuit board, a protection ring surrounding the flip chip and having an upper opening is mounted on the circuit board, and the flip ring is mounted in the protection ring. In a semiconductor device filled with a gel and packaged with a package resin, an outer peripheral surface of the protective ring is formed into a curved surface so that an outer diameter thereof is reduced from a lower end surface toward an upper end surface, and the upper surface of the protective ring is formed. Since the opening is closed by the ring cover, the occurrence of cracks in the exterior resin at the entire outer periphery of the protection ring and at the interface between the exterior resin and the gel is suppressed, and the moisture resistance of the exterior resin can be improved, improving reliability. In addition, the flip chip can be prevented from being damaged by external force.

Further, according to the third aspect of the invention, mounted flip-chip on a circuit board, mounting the protective cover on the circuit board surrounding the flip-chip, a protective cover
In a semiconductor device that is filled with gel and packaged with a package resin, the protective cover has a hollow hemispherical shape, and the protective cover has a gel injection hole and an air vent hole. The occurrence of cracks in the exterior resin at the entire outer periphery of the cover and at the interface between the exterior resin and the gel is suppressed, the moisture resistance of the exterior resin can be improved, reliability can be improved, and breakage of the flip chip due to external force can be prevented. can do.

According to the fourth aspect of the present invention, a flip chip is mounted on a circuit board , a protection ring surrounding the flip chip and having an upper opening is mounted on the circuit board, and the flip ring is mounted in the protection ring. In a semiconductor device that is filled with gel and packaged with a package resin, a protective cover having a smooth curved outer peripheral surface is mounted on the circuit board so as to surround and store the protective ring. The occurrence of cracks in the exterior resin at the entire outer periphery of the cover and at the interface between the exterior resin and the gel is suppressed, the moisture resistance of the exterior resin can be improved, reliability can be improved, and breakage of the flip chip due to external force can be prevented. can do.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a semiconductor device according to a second embodiment of the present invention;

FIG. 3 is a sectional view of a semiconductor device according to a third embodiment of the present invention;

FIG. 4 is a sectional view of a semiconductor device according to a fourth embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating an example of a conventional semiconductor device.

[Explanation of symbols]

1 Flip chip, 2 ceramic substrate (circuit board), 4 silicon gel (gel), 5 exterior resin, 6
Protective ring, 7 Ring cover, 9 Protective ring, 10
Ring cover, 11 protective cover , 12 air vent hole, 13 gel injection hole, 14 protective cover .

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI H01L 25/18

Claims (4)

(57) [Claims] 1. A flip chip is mounted on a circuit board,
In a semiconductor device comprising a protection ring surrounding the flip chip and having an upper opening on the circuit board, filling the protection ring with gel, and packaging with a packaging resin, an outer periphery of the protection ring A semiconductor device wherein a surface is formed so as to be inclined so that an outer diameter thereof is reduced from a lower end surface toward an upper end surface, and an upper opening of the protection ring is closed by a ring cover. 2. A flip chip mounted on a circuit board,
In a semiconductor device comprising a protection ring surrounding the flip chip and having an upper opening on the circuit board, filling the protection ring with gel, and packaging with a packaging resin, an outer periphery of the protection ring A semiconductor device having a surface formed into a curved surface such that an outer diameter thereof is reduced from a lower end surface toward an upper end surface, and an upper opening of the protection ring is closed by a ring cover. 3. A flip chip is mounted on a circuit board,
Protective cover on the circuit board surrounding the flip chip
In a semiconductor device in which a bar is attached, gel is filled in the protective cover , and the protective cover is packaged with a package resin, the protective cover is formed into a hollow hemispherical shape and the protective cover is formed.
A semiconductor device having a gel injection hole and an air vent hole formed in a cover . 4. A flip chip is mounted on a circuit board,
Open the top on the circuit board surrounding the flip chip
A protective ring having an opening is attached, a gel is filled in the protective ring, and the semiconductor device is packaged with a package resin, and a protective cover having a smooth curved outer peripheral surface surrounds the protective ring. A semiconductor device mounted on the circuit board so as to be accommodated.