JP2001196507A - Semiconductor device and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor element 3a, 3b, which is internally and normally sealed, for a long period of time due to cracks in an insulating substrate 1, peeling or rupture in a sealing resin 6, and for a long time. Cannot be operated. SOLUTION: A substantially square plate-like shape having a concave portion 1b for accommodating a semiconductor element 3b on one main surface, and a plurality of wiring conductors 4 arranged from the inside of the concave portion 1b to the outer peripheral portion of the main surface. The insulating base 1, the semiconductor element 3 b mounted on the bottom surface of the concave portion 1 b, and one end joined to a portion led out to the outer periphery of the main surface of the wiring conductor 4, and the other end directed outward from the side surface of the insulating base 1 A plurality of projecting external lead terminals 2 and an insulating base 1
The semiconductor device 3b comprises a sealing resin 6 for sealing one end of the external lead terminal 2, and the recess 1b is a semiconductor device whose side surface is an inclined surface or a stepped surface. The stress is satisfactorily dispersed and alleviated on the side surface of the concave portion 1b which is an inclined surface or a step-like surface, so that the occurrence of cracks in the insulating base 1 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-sealed semiconductor device used for an information processing device such as a computer.

[0002]

2. Description of the Related Art Conventionally, a resin-encapsulated semiconductor device used for an information processing device such as a computer includes a semiconductor element,
The semiconductor device includes a die pad on which a semiconductor element is mounted, a large number of external lead terminals extending at predetermined intervals from the periphery of the die pad, and a sealing resin for sealing the semiconductor element, the die pad, and a portion near the die pad of the external lead terminal. . In this semiconductor device, a lead frame in which a die pad and a large number of external lead terminals are integrally connected via a frame-shaped connecting band is prepared, and a semiconductor element is mounted and fixed on the upper surface of the die pad of the lead frame. Then, each electrode of the semiconductor element is electrically connected to a portion of the external lead terminal near the die pad via a bonding wire, and the semiconductor element, the die pad, and the portion of the external lead terminal near the die pad are sealed with a sealing resin. It is manufactured by.

A lead frame is made of a metal mainly composed of copper or iron, and is manufactured by subjecting a thin plate of a metal mainly composed of copper or iron to metal processing such as punching or etching which is conventionally known. Is done.

In such a conventional semiconductor device, a semiconductor element, a die pad, and a portion of an external lead terminal near a die pad are sealed with a sealing resin, and then the external lead terminal is cut and separated from a frame-shaped connecting band. The external lead terminals are electrically independent, and the outer end of each external lead terminal is connected to the wiring conductor of the external electric circuit board via solder, so that each electrode of the semiconductor element housed inside is connected via the external lead terminal. To be connected to an external electric circuit.

In recent years, however, the density and integration of semiconductor elements have been rapidly increasing, and the number of electrodes has been greatly increased. Accordingly, each electrode of the semiconductor element has been connected to an external electric circuit. External lead terminals also have a line width of, for example, 0.
It is as thin as 3 mm or less, and the interval between adjacent external lead terminals is also as extremely small as 0.3 mm or less. Therefore, in this conventional semiconductor device, when an external force is applied to the external lead terminal, for example, when connecting the external lead terminal to an external electric circuit, the external lead terminal is easily deformed by the external force, and the adjacent external lead terminal is deformed. However, there has been a problem in that a short circuit may occur due to contact, and the external lead terminal cannot be accurately and firmly connected to a predetermined external electric circuit. There is also a demand for accommodating a plurality of semiconductor elements in one semiconductor device, thereby increasing the mounting density of the semiconductor elements on an external electric circuit board and increasing the speed of signal transmission and reception between the semiconductor elements. Was.

Therefore, in order to solve the above-mentioned problems and to satisfy the above-mentioned requirements, as shown in a sectional view of FIG. 9, an electrically insulating material such as an aluminum oxide sintered body is used. The semiconductor element mounting part 21a on which the semiconductor element 23a is mounted has a concave part 21b in the center of the lower surface in which the semiconductor element 23b is accommodated, and fan-likely spreads from the periphery of the semiconductor element mounting part 21a and the inside of the concave part 21b to the peripheral part of the upper surface. A substantially rectangular plate-shaped insulating base 21 having a plurality of wiring conductors 24 made of metal powder such as tungsten or molybdenum to be derived, and a semiconductor element mounting portion 21a of the insulating base 21, and its electrodes A semiconductor element 23a electrically connected to the inner end via a bonding wire 25a and a semiconductor element 23a housed in the recess 21b, and its electrode is bonded to the wiring conductor 24. A semiconductor element 23b which is electrically connected via the ear 25b, one end wiring conductor 24
A plurality of external lead terminals 22 which are joined to a portion of the upper surface of the insulating base 21 extending to the outer peripheral portion and the other end of which protrudes outward from a side surface of the insulating base 21; the insulating base 21 and the semiconductor elements 23a and 23b. A semiconductor device comprising a sealing resin 26 made of a thermosetting resin such as an epoxy resin for sealing one end of the external lead terminal 22 has been proposed. According to such a semiconductor device, since the external lead terminal 22 is attached to the outer end portion of the fan-shaped spread wiring conductor 24, the external lead terminal 22 has a large line width and a large adjacent space. It is possible to maintain electrical insulation between adjacent external lead terminals 22 while effectively preventing deformation of the external lead terminals 22. Also, two semiconductor elements 23a are provided in the same semiconductor device.
.Since 23b is housed close to the semiconductor element
The packing density of the external electric circuit boards 23a and 23b is increased, and the transmission and reception of signals between the semiconductor elements 23a and 23b can be performed at a high speed over a short distance.

To manufacture such a semiconductor device, first, a semiconductor element 23 is placed in a concave portion 21b formed on the lower surface of the insulating base 21.
b, and each electrode of the semiconductor element 23b is electrically connected to the wiring conductor 24 via a bonding wire 25b. Then, the semiconductor element is mounted on the semiconductor element mounting portion 21a formed on the upper surface side of the insulating base 21. With the element 23a mounted,
Each electrode of the semiconductor element 23a is electrically connected to the wiring conductor 24 via a bonding wire 25a. Thereafter, as shown in a sectional view of FIG. An upper mold 51 having a cavity 51a having a shape corresponding to the surface shape of the above, and a lower mold having a cavity 52a having a shape corresponding to the surface shape of the lower half of the sealing resin 26 on the upper surface side.
52, the insulating base 21 and the semiconductor elements 23a and 23b, and one end of the external lead terminal 22 are positioned in the cavities 51a and 52a of the mold 50. Is set by sandwiching it between an upper mold 51 and a lower mold 52, and then, as shown in a sectional view in FIG.
By injecting the sealing resin 26 in a liquid state into the insides 51a and 52a and thermally curing the same, the insulating base 21 and the semiconductor elements 23a and 23
b and one end of the external lead terminal 22 are sealed with a thermosetting sealing resin 26.

The cavity 51a of the mold 50 is
In order to inject the sealing resin 26 into the liquid 52a in a liquid state, the resin injection path 53 for injecting the resin and the air are discharged between the upper mold 51 and the lower mold 52 of the mold 50. A method of injecting the liquid sealing resin 26 into the mold 50 through the resin injection path 53 is provided.

In this semiconductor device, the insulating substrate
The reason why the semiconductor element 23b mounted on the lower surface side of the semiconductor device 21 is accommodated in the recess 21b is that the semiconductor element 23a is mounted on the semiconductor element mounting portion 21a on the upper surface of the insulating base 21.
This is to prevent the b and the bonding wire 25b from being damaged by contacting an external member or the like.

[0010]

However, in the conventional semiconductor device as shown in FIG. 9, the side surface of the concave portion 21b formed on the lower surface of the insulating base 21 rises substantially perpendicularly to the bottom surface of the concave portion 21b. Therefore, the structure is such that stress is easily concentrated on the corner between the bottom surface and the side surface of the concave portion 21b. Therefore, when heat or the like generated during the operation of the semiconductor elements 23a and 23b is repeatedly applied to the insulating base 21 and the sealing resin 26, the stress generated due to the difference in the coefficient of thermal expansion between the insulating base 21 and the sealing resin 26 is reduced. Acting intensively at the corner between the side surface and the bottom surface of 21b, cracks are generated in the insulating base 21 starting from this corner, and as a result, the wiring conductor 24 attached to the insulating base 21 However, there is a problem that the semiconductor elements 23a and 23b cannot be normally operated due to disconnection as the crack progresses.

In this semiconductor device, when the semiconductor device is manufactured, the insulating base 21 to which the semiconductor elements 23a and 23b and the external lead terminals 22 are joined is molded with a molding die 50.
When the sealing resin 26 is injected in a liquid state into the mold 50 after being set in the mold 50, the side surface of the concave portion 21b rises substantially vertically from the lower surface of the insulating base 21 to the bottom surface of the concave portion 21b.
The liquid sealing resin 26 does not satisfactorily wrap around the corner between the side surface 21b and the bottom surface of the concave portion 21b, and air is caught in the sealing resin 26 at this portion to form a large void,
When such voids are generated, the semiconductor elements 23a and 23b
The air and the like trapped in the voids thermally expand due to the heat and the like generated during the operation, causing the sealing resin 26 to peel or rupture. As a result, the hermetic sealing by the sealing resin 26 is incomplete. As a result, the semiconductor element 23b housed in the recess 21b cannot be operated normally for a long period of time.

The present invention has been devised in view of such conventional problems, and has as its object to prevent the occurrence of cracks in the insulating base or peeling or bursting of the sealing resin. Accordingly, it is an object of the present invention to provide a semiconductor device and a method for manufacturing the same, which enable a semiconductor element sealed therein to operate normally and stably for a long period of time.

[0013]

According to the present invention, there is provided a semiconductor device comprising:
A substantially square plate-shaped insulating base having a concave portion for accommodating the semiconductor element on one main surface, and a plurality of wiring conductors arranged from the inside of the concave portion to the outer peripheral portion of the main surface;
A semiconductor element mounted on the bottom surface of the concave portion, and a plurality of external lead terminals, one end of which is joined to a portion led out to the outer peripheral portion of the main surface of the wiring conductor, and the other end of which protrudes outward from a side surface of the insulating base; A semiconductor device comprising an insulating base, a semiconductor element, and a sealing resin for sealing one end of an external lead terminal, wherein the recess has a side surface formed as an inclined surface or a stepped surface. .

Further, a method of manufacturing a semiconductor device according to the present invention
A substantially square plate-shaped insulating base having a concave portion for accommodating the semiconductor element on one main surface, and a plurality of wiring conductors arranged from the inside of the concave portion to the outer peripheral portion of the main surface;
A semiconductor element mounted on the bottom surface of the concave portion, and a plurality of external lead terminals each having one end joined to a portion led out to the outer peripheral portion of the main surface of the wiring conductor and the other end projecting outward from a side surface of the insulating base. One end of the insulating base, the semiconductor element, and the external lead terminals are set by setting the mold in a mold having cavities on both main surface sides of the insulating base and injecting and curing a liquid resin in the mold. A method for manufacturing a semiconductor device in which is sealed with a sealing resin,
The side surface of the concave portion of the insulating base may be an inclined surface or a stepped surface.

According to the semiconductor device of the present invention, since the side surface of the concave portion is an inclined surface or a stepped surface, the stress applied to the corner between the side surface and the bottom surface of the concave portion of the insulating substrate is favorably applied to the side surface of the concave portion. Can be alleviated.

Further, according to the method of manufacturing a semiconductor device of the present invention, by setting the side surface of the concave portion of the insulating substrate to be an inclined surface or a stepped surface, the insulating substrate is set in a mold, and then the mold metal is set. When the liquid sealing resin is injected into the mold, the liquid sealing resin flows well along the side surface of the concave portion. As a result, the inside of the concave portion is well filled with the sealing resin, and a large void is formed in the sealing resin. Can be effectively prevented from being formed.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view showing an embodiment of a semiconductor device according to the present invention, wherein 1 is an insulating base, 2 is an external lead terminal, 3a and 3b are semiconductor elements, and 6 is a sealing resin. FIG. 2 is a top view of the semiconductor device shown in FIG. 1 excluding the sealing resin 6.

The insulating substrate 1 is made of an electrically insulating material such as a sintered body of aluminum oxide, a sintered body of aluminum nitride, a sintered body of mullite, a sintered body of silicon carbide, a sintered body of silicon nitride, and glass ceramic. Having a semiconductor element mounting portion 1a in which the semiconductor element 3a is mounted in the center of the upper surface, and a concave portion 1b in which the semiconductor element 3b is accommodated in the center of the lower surface. The semiconductor element 3a is fixed to the semiconductor element mounting portion 1a, and the semiconductor element 1b is fixed to the bottom surface of the concave portion 1b via an adhesive such as brazing material, glass, resin, or the like.

The insulating substrate 1 is provided with a semiconductor element mounting portion 1.
A large number of wiring conductors 4 made of metal powders of metal such as tungsten, molybdenum, copper, silver, etc., spreading in a fan shape from the periphery of a and the inside of the concave portion 1b to the outer peripheral portion are formed. The wiring conductor 4 functions as a conductive path for electrically connecting the respective electrodes of the semiconductor elements 3a and 3b to the external lead terminals 2, and the inner ends of the respective electrodes of the semiconductor elements 3a and 3b are provided with bonding wires. These are electrically connected via 5a and 5b, respectively, and one end of the external lead terminal 2 is joined to the outer end. And the wiring conductor 4
It spreads like a fan from the inner end to the outer end, and the line width and the adjacent interval at the outer end are wide,
Thereby, the line width and the adjacent distance of the external lead terminal 2 joined to the outer end can be widened.

External lead terminal 2 joined to wiring conductor 4
Is a terminal for connecting the semiconductor elements 3a and 3b to an external electric circuit. The semiconductor elements 3a and 3b are connected by connecting the external lead terminals 2 to the wiring conductors of the external electric circuit board.
b is electrically connected to an external electric circuit via the wiring conductor 4 and the external lead terminal 2. The external lead terminal 2 has a line width and an adjacent interval of, for example, 0.3.
mm, so that even if an external force is applied to the external lead terminals 2, the external lead terminals 2 will not be greatly deformed, and the electrical insulation between the adjacent external lead terminals 2 will be reduced. The external lead terminals 2 can be accurately and reliably electrically connected to a predetermined external electric circuit while maintaining them.

The insulating base 1 and the semiconductor elements 3a.
3b and one end of the external lead terminal 2 joined to the wiring conductor 4 are sealed with a sealing resin 6 such as an epoxy resin, so that the semiconductor elements 3a and 3b are air-tightly sealed, and from the external environment. Is protected. In this example, the side surface of the concave portion 1b of the insulating base 1 is an inclined surface. As a result, thermal stress generated due to a difference in thermal expansion coefficient between the insulating base 1 and the sealing resin 6 is reduced.
Even if the stress is repeatedly applied to the inner surface side of the concave portion 1b, the stress is satisfactorily dispersed and alleviated on the side surface of the concave portion 1b which is an inclined surface, and as a result, cracks are effectively prevented from being generated in the insulating base 1. It is possible to always operate the semiconductor elements 3a and 3b normally without breaking the wiring conductor 4.

The side surface of the concave portion 1b has an inclination angle A.
If it is less than 10 °, it is necessary to make the size of the insulating base 1 extremely large in order to obtain the required depth as the concave portion 1b, which makes it difficult to reduce the size of the semiconductor device. When it exceeds, it becomes difficult to satisfactorily disperse and relax the stress applied to the corner between the side surface and the bottom surface of the concave portion. Therefore, the inclination angle A of the side surface of the recess 1b is preferably in the range of 10 to 80 °.

Further, a chamfered portion 1c having a width of, for example, 0.1 mm or more and an angle of 10 to 80 ° with respect to the outer peripheral side surface of the insulating substrate 1 is formed at a corner between the outer peripheral side surface and the lower surface of the insulating substrate 1. In addition, the stress applied to the sealing resin 6 in contact with the corner due to the difference in thermal expansion coefficient between the insulating base 1 and the sealing resin 6 can be satisfactorily dispersed and relaxed. By making the thickness between the side surfaces of the sealing resin 6 large, cracks in the sealing resin 6 can be effectively prevented. Therefore, it is preferable to form a chamfered portion 1c having a width of 0.1 mm or more and an angle of 10 to 80 ° with respect to the outer peripheral side surface of the insulating substrate 1 at the corner between the outer peripheral side surface and the lower surface of the insulating substrate 1.

FIG. 3 shows another embodiment of the semiconductor device according to the present invention. In the example shown in FIG. 3, similarly to the above-described example, a semiconductor element mounting portion 11a made of an electrically insulating material such as an aluminum oxide sintered body and having a semiconductor element 13a mounted on a central portion of the upper surface and a central portion of the lower surface is formed on the lower surface. A plurality of metal powders, such as tungsten and molybdenum, having a concave portion 11b for accommodating the semiconductor element 13b and extending in a fan shape from the periphery of the semiconductor element mounting portion 11a and from the inside of the concave portion 11b to the outer peripheral portion of the upper surface. A substantially rectangular flat insulating substrate 11 having a wiring conductor 14 and a semiconductor element mounting portion 11a of the insulating substrate 11
A semiconductor element 13a electrically connected to an inner end portion of the 14 through a bonding wire 15a, and a semiconductor element 13a housed in the recess 11b;
A semiconductor element 13b whose electrode is electrically connected to the wiring conductor 14 via a bonding wire 15b, and one end is joined to a portion of the wiring conductor 14 which is led to the outer periphery of the upper surface of the insulating base 11 and the other end is connected. A plurality of external lead terminals 12 projecting outward from the side surfaces of the insulating base 11, and a thermosetting resin such as an epoxy resin sealing one end of the insulating base 11, the semiconductor elements 13a and 13b, and the external lead terminals 12. And a sealing resin 16. In this example, the side surface of the concave portion 11b of the insulating base 11 is a stepped surface. In the case of this example, since the side surface of the concave portion 11b is a stepped surface, the thermal stress generated due to the difference in thermal expansion coefficient between the insulating base 11 and the sealing resin 16 causes the concave portion of the insulating base 11 Even if the stress is repeatedly applied to the inner surface side of 11b, the stress is satisfactorily dispersed and alleviated on the side surface of the concave portion 11b having the stepped surface, and as a result, cracks are effectively prevented from being generated in the insulating base 11. Therefore, the semiconductor elements 13a and 13b can always be normally operated without breaking the wiring conductor 14.

The side surface of the recess 11b has a height of each step of 0.
If it exceeds 5 mm, it tends to be difficult to satisfactorily disperse and relax the stress on this side. Therefore, the height of each step of the recess 11b is preferably 0.5 mm or less. When the inclination angle A is less than 10 °, the side surface of the concave portion 11b is formed on the insulating base 11 to obtain a necessary depth as the concave portion 11b.
Needs to be extremely large, which makes it difficult to reduce the size of the semiconductor device. On the other hand, if it exceeds 80 °, the stress applied to the corner between the side surface and the bottom surface of the concave portion is reduced. It becomes difficult to favorably mitigate the dispersion. Therefore, the inclination angle A of the side surface of the concave portion 11b is 10 to 80.
The range of ゜ is preferred.

Further, a chamfered portion 11c having a width of, for example, 0.1 mm or more and an angle of 10 to 80 ° with respect to the outer peripheral side surface of the insulating substrate 11 is formed at a corner between the outer peripheral side surface and the lower surface of the insulating substrate 11. The stress applied to the sealing resin 16 in contact with the corners due to the difference in the thermal expansion coefficient between the insulating base 11 and the sealing resin 16 can be satisfactorily dispersed and relaxed. By making the thickness between the side surfaces of the sealing resin 16 large, cracks in the sealing resin 16 can be effectively prevented. Therefore, it is preferable to form a chamfered portion 11c having a width of 0.1 mm or more and an angle of 10 to 80 ° with respect to the outer peripheral side surface of the insulating substrate 11 at the corner between the outer peripheral side surface and the lower surface of the insulating substrate 11.

Next, a method of manufacturing a semiconductor device according to the present invention will be described with reference to an example of manufacturing the semiconductor device shown in FIG.

First, as shown in the sectional view of FIG. 4, an insulating base 1, external lead terminals 2, and semiconductor elements 3a and 3b are prepared.

When the insulating substrate 1 is made of, for example, an aluminum oxide sintered body, an appropriate binder and a solvent are added to a raw material powder such as aluminum oxide, silicon oxide, calcium oxide, and magnesium oxide, and the mixture is mixed to form a slurry. In addition, a plurality of ceramic green sheets for the insulating substrate 1 are obtained by adopting a sheet forming technique such as a doctor blade method or a calender roll method, which is well known in the art, to obtain a plurality of ceramic green sheets. The green sheet is appropriately punched, and a metal paste for the wiring conductor 4 is printed and applied in a predetermined pattern by using a conventionally known thick film technique such as a screen printing method. It has a concave part on the lower surface, which is vertically stacked and cut into a predetermined shape, and the side surface becomes an inclined surface. Give the ceramic molded body, finally in a reducing atmosphere the green ceramic body is fabricated by firing at a temperature of about 1600 ° C.. The metal paste for the wiring conductor 4 can be obtained, for example, when the wiring conductor is made of tungsten metallization, by adding and mixing a suitable binder and solvent to tungsten powder to form a paste. Usually, a metal having excellent corrosion resistance, such as nickel or gold, and having excellent wire bonding properties and wettability with a brazing material is formed on the exposed surface of the wiring conductor 4 by electrolytic plating or electroless plating. It is plated to a thickness of 1 to 20 μm.

On the other hand, the external lead terminal 2 is formed into a predetermined shape by subjecting a thin plate made of a metal such as a copper alloy containing copper as a main component or an iron alloy containing iron as a main component to an appropriate punching process or etching process. It is produced in. In order to hold the external lead terminals 2 at a predetermined interval, the external ends of the external lead terminals 2 are connected by a frame-shaped connecting band integrally formed with the respective lead terminals 2. Preferably. Such a connecting band may be cut and removed from the external lead terminal 2 before connecting the external lead terminal 2 to the external electric circuit board.

The semiconductor elements 3a and 3b are manufactured by a conventional method.

Next, as shown in the sectional view of FIG. 5, one end of the external lead terminal 2 is connected to the outer end of the wiring conductor 4 by a silver-copper alloy, a gold-tin alloy, a gold-germanium alloy, a silver-tin. The semiconductor element 3a is joined to the semiconductor element mounting portion 1a by the brazing material such as an alloy, lead-tin alloy, gold-tin-lead-silver alloy, gold-tin-lead-palladium alloy, and the bottom surface of the recess 1b. The semiconductor element 3b is bonded and fixed via an adhesive made of a brazing material such as a gold-silicon alloy or a resin such as an epoxy resin, and the respective electrodes of the semiconductor elements 3a and 3b are wired via bonding wires 5a and 5b. Connect to conductor 4.

Finally, as shown in the cross-sectional view of FIG. 6, the insulating substrate 1 to which the semiconductor elements 3a and 3b and the external lead terminals 2 are joined is formed on the lower surface into the surface shape of the upper half of the sealing resin 6. In a mold die 30 comprising an upper die 31 having a cavity 31a of a corresponding shape and a lower die 32 having a cavity 32a of a shape corresponding to the lower half surface shape of the sealing resin 6 on the upper surface side. As shown in a sectional view of FIG. 7, the sealing resin 6 such as an epoxy resin is injected into the molding die 30 in a liquid state through a resin injection path 33 and thermally cured, thereby obtaining As shown, a semiconductor device in which the insulating base 1, the semiconductor elements 3a and 3b, and one end of the external lead terminal 2 are sealed with the sealing resin 6 is completed. At this time, in this example, the concave portion 1b of the insulating base 1 is used.
It is important that the side surface is inclined at, for example, 10 ° to 80 °. In this example, the concave portion 1b of the insulating base 1
Is inclined, for example, at an angle of 10 to 80 °. Therefore, when the insulating base 1 is set in the mold 30 and the liquid sealing resin 6 is injected, the liquid sealing resin 6 is inclined. Flows well along the side surface of the concave portion 1b, and the inside of the concave portion 1b is filled with the sealing resin 6 without any gap. As a result, a large void is not formed inside the sealing resin 6. . Therefore, according to the manufacturing method of this example, it is possible to provide a semiconductor device having excellent hermetic reliability, in which air or the like sealed in the voids does not thermally expand and peeling or rupture occurs in the sealing resin 6. Can be. In addition, the concave portion 1
When the inclination angle A of the side surface of b is less than 10 °, it is necessary to make the size of the insulating substrate 1 extremely large in order to obtain the necessary depth as the concave portion 1b, which makes it difficult to miniaturize the semiconductor device. On the other hand, when the angle exceeds 80 °, when the insulating base 1 is set in the mold 30 and the liquid sealing resin 6 is injected, the liquid resin 6 is satisfactorily formed along the side surface of the concave portion 1b. The inside of the concave portion 1b does not flow and the sealing resin 6
Tend to be difficult to fill without gaps. Therefore, the inclination angle A of the side surface of the concave portion 1b is preferably in the range of 10 to 80 °. Further, if a chamfered portion 1c having a width of 0.1 mm or less and an angle of 10 to 80 ° with the outer peripheral side surface of the insulating substrate 1 is formed at a corner between the outer peripheral side surface and the lower surface of the insulating substrate 1,
When the liquid sealing resin 6 is injected into the molding die 30 on which the insulating base 1 is set, the distance between the insulating base 1 and the side surface of the cavity 32a of the lower die 32 becomes wide, so that the insulating base 1 The liquid sealing resin 6 can be favorably injected between the lower surface and the lower mold 32. Therefore, a chamfered portion 1c having a width of 0.1 mm or less and an angle of 10 to 80 ° with the outer peripheral side surface of the insulating substrate 1 is formed at a corner between the outer peripheral side surface and the lower surface of the insulating substrate 1. Is preferred.

When the embodiment shown in FIG. 3 is manufactured, as shown in the sectional view of FIG.
Insulating substrate 11 to which 13b and external lead terminals 12 are bonded
An upper mold 41 having a cavity 41a having a shape corresponding to the upper half surface shape of the sealing resin 16 on the lower surface side, and a cavity having a shape corresponding to the lower half surface shape of the sealing resin 16 on the upper surface side After setting in a mold 40 comprising a lower mold 42 having a 42a, a sealing resin 16 such as an epoxy resin is injected into the mold 40 in a liquid state through a resin injection path 43 and thermoset. By doing so, as shown in FIG. 3, a semiconductor device in which the insulating base 11, the semiconductor elements 13a and 13b, and one end of the external lead terminal 12 are sealed with the sealing resin 16 is completed. In this case, since the side surface of the concave portion 11b of the insulating base 11 is a stepped surface having an inclination angle A of, for example, 10 to 80 °, the insulating base 11 is set in the mold 40 and the liquid sealing resin is set. When 16 is injected, liquid sealing resin
16 flows well along the side surface of the concave portion 11b that has become a stepped surface, and the inside of the concave portion 11b is filled with the sealing resin 16 without gaps,
As a result, a large void is not formed inside the sealing resin 16. The inclination angle A of the side surface of the recess 11b
Is less than 10 °, it is necessary to make the size of the insulating base 11 extremely large in order to obtain a necessary depth for the concave portion 11b, which makes it difficult to reduce the size of the semiconductor device. Is exceeded, when the insulating base 11 is set in the mold 40 and the liquid sealing resin 16 is injected, the liquid resin 16 does not flow well along the side surface of the concave portion 11b and flows through the concave portion 11b. It tends to be difficult to fill the gap with the sealing resin 16 without gaps. Therefore, the inclination angle A of the side surface of the recess 11b is preferably in the range of 10 to 80 °.

Note that the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present invention. For example, in the above-described embodiment, the insulating bases 1 and 11 are formed from ceramics such as an aluminum oxide sintered body.
Are materials other than ceramics, such as thermosetting polyimide resin and BT resin (Bismaleimide Triazine Resi
n). It may be formed from a glass epoxy resin substrate, a glass plate, or the like. In the above embodiment, the wiring conductors 4 and 14 are formed from metal powder metallization such as tungsten metallization. However, the wiring conductors 4 and 14 are formed from metal thin films such as copper, aluminum and gold. Is also good. Further, the wiring conductor 4
A capacitance element, a resistance element, or the like connected to 14 may be provided. Furthermore, in the above embodiment, the semiconductor element 3a
・ 3b ・ 13a ・ 13b are bonding wires 5a
Although the electrodes of the semiconductor elements 3a, 3b, 13a, and 13b may be connected to the wiring conductors 4 and 14 by flip-chip connection, the electrodes are connected to the wiring conductors 4 and 14 via 5b, 15a, and 15b. .

[0037]

According to the semiconductor device of the present invention, since the side surface of the concave portion is an inclined surface or a stepped surface, the stress applied to the corner between the side surface and the bottom surface of the concave portion of the insulating base is reduced. In the aspect of dispersion can be satisfactorily alleviated, as a result,
It is possible to provide a semiconductor device in which a semiconductor element can always be normally operated without causing cracks in an insulating base and without breaking a wiring conductor.

Further, according to the method of manufacturing a semiconductor device of the present invention, by setting the side surface of the concave portion of the insulating base as an inclined surface or a stepped surface, the insulating base is set in a mold, and then the mold is set. When the liquid sealing resin is injected into the mold, the liquid sealing resin flows well along the side surface of the concave portion. As a result, the inside of the concave portion is well filled with the sealing resin, and a large void is formed in the sealing resin. Can be effectively prevented, and as a result, the air or the like sealed in the voids does not thermally expand and the sealing resin does not peel or burst, and the semiconductor element housed inside , Which can operate normally and stably over a long period of time, and has excellent airtight reliability.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of a semiconductor device of the present invention.

FIG. 2 is a top view of the semiconductor device shown in FIG. 1 excluding a sealing resin 6;

FIG. 3 is a sectional view showing another example of the embodiment of the semiconductor device of the present invention.

FIG. 4 is a cross-sectional view for describing the method for manufacturing a semiconductor device according to the present invention.

FIG. 5 is a sectional view for illustrating the method for manufacturing a semiconductor device according to the present invention.

FIG. 6 is a cross-sectional view for describing the method for manufacturing a semiconductor device according to the present invention.

FIG. 7 is a cross-sectional view for explaining the method for manufacturing a semiconductor device according to the present invention.

FIG. 8 is a sectional view for illustrating the method for manufacturing the semiconductor device shown in FIG.

FIG. 9 is a cross-sectional view showing a conventional semiconductor device.

10 is a cross-sectional view for explaining the method for manufacturing the semiconductor device shown in FIG.

11 is a cross-sectional view for explaining the method for manufacturing the semiconductor device shown in FIG.

[Explanation of symbols]

 1, 11 ... Insulating base 1a, 11a .... Semiconductor element mounting part 1b, 11b .... Concave part 2, 12, ... ... External lead terminals 3a, 3b, 13a, 13b semiconductor elements 4, 14,..., Wiring conductors 6, 16,.

Claims (2)

[Claims] 1. A substantially square plate-shaped insulating base having a concave portion for accommodating a semiconductor element on one main surface, and a plurality of wiring conductors arranged from the inside of the concave portion to the outer peripheral portion of the main surface. And a plurality of semiconductor elements mounted on the bottom surface of the concave portion, one end of which is joined to a portion of the wiring conductor extending to the outer peripheral portion of the main surface, and the other end of which protrudes outward from a side surface of the insulating base. And a sealing resin for sealing the insulating base, the semiconductor element, and the one end of the external lead terminal, wherein the side surface of the concave portion has an inclined surface or a stepped shape. A semiconductor device, which is provided as a surface. 2. A substantially square-plate-shaped insulating base having a concave portion for accommodating a semiconductor element on one main surface and a plurality of wiring conductors arranged from the inside of the concave portion to the outer peripheral portion of the main surface. And a plurality of semiconductor elements mounted on the bottom surface of the concave portion, one end of which is joined to a portion of the wiring conductor extending to the outer peripheral portion of the main surface, and the other end of which protrudes outward from a side surface of the insulating base. The external lead terminals are set in a mold having cavities on both main surfaces of the insulating base, and a liquid resin is injected into the mold to cure the insulating base. A method for manufacturing a semiconductor device for sealing one end of the semiconductor element and the external lead terminal with a sealing resin,
A method of manufacturing a semiconductor device, wherein a side surface of the concave portion of the insulating base is an inclined surface or a stepped surface.