JPH08264681A - Semiconductor device - Google Patents

Abstract

PURPOSE: To obtain a semiconductor device for restoring a crack due to thermal stress generated at the joint part between the semiconductor chip of the semiconductor device and a base. CONSTITUTION: A semiconductor chip 1 is joined to a base 2 by a joint metal 7 whose melt point is less than 183 deg.C and the semiconductor chip 1 is sealed along with at least either of an inactive gas 8 and a reducing substance 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device in which a semiconductor chip and a base material are joined with metal and sealed.

[0002]

2. Description of the Related Art FIG. 11 is a sectional view showing a conventional semiconductor device. In the figure, 1 is a semiconductor chip made of, for example, silicon, 2 is a substrate such as an alumina ceramic package, 3 is a semiconductor chip 1 and a base. A joining metal that joins the material 2 with, for example, a solder alloy having a composition of 95% Pb-5% Sn, 4 is a lead for electrically connecting the semiconductor chip 1 to the outside, and 5 is a terminal of the semiconductor chip 1 and a lead. 4 is a bonding wire for electrically connecting 4 to each other. Such a semiconductor device is described in, for example, “MITSUBISHI ELECTRIC CO., LTD.
ISHI DATA BOOK IC PACKAGES) "(issued in October 1989).

[0003]

Since the conventional semiconductor device is configured as described above, the Si of the semiconductor chip 1 is
And the solder alloy of the bonding metal 3, or the solder alloy and the alumina of the base material 2 have large thermal expansion coefficients, so that heat generated from the semiconductor device itself during operation and the environment in which the semiconductor device is installed Due to the temperature change of the semiconductor chip 1 and the base material 2, a thermal stress is generated in the joint portion between the semiconductor chip 1 and the base material 2, which causes cracks 6 in the solder alloy as the joint metal 3 of the joint portion.
However, there is a problem that the semiconductor device is eventually generated and propagated, and eventually the semiconductor device is destroyed.

The present invention has been made in order to solve the above-mentioned problems, and is provided with a joint portion that can be restored to its original state even if a joint portion between the semiconductor chip and the base material is cracked. The purpose is to obtain a semiconductor device.

Further, according to the present invention, even if an external force such as vibration acts on the semiconductor device during the heating for repairing the crack, the semiconductor chip is not displaced or moved, and the bonding wire is cut. The purpose is to obtain no semiconductor device.

[0006]

According to another aspect of the present invention, there is provided a semiconductor device in which a semiconductor chip is bonded to a base material by a bonding metal having a melting point of less than 183 ° C.
It is sealed with at least one of an inert gas and a reducing substance arranged in contact with the bonding metal.

In a semiconductor device according to a second aspect of the present invention, the bonding metal is mainly composed of lead, tin, bismuth, indium or antimony as a main component or an alloy containing at least two or more of these metals. It is a thing.

In a semiconductor device according to a third aspect of the present invention, the through-hole in the central portion of the metal is made of a high melting point bonding metal having a melting point of 183 ° C. or higher, and the other portions are made of a bonding metal having a melting point of less than 183 ° C. The semiconductor chip is sealed with at least one of an inert gas and a reducing substance arranged in contact with the bonding metal.

In a semiconductor device according to a fourth aspect of the present invention, the bonding metal of the portion other than the penetrating portion contains lead, tin, bismuth, indium or antimony as a main component, or at least two or more of these metals. The main component is an alloy, and the high melting point bonding metal in the penetration part is lead, tin,
Indium, antimony, silver, gold, platinum, palladium,
The main component is silicon or aluminum, or the main component is an alloy containing at least two or more of these metals.

In the semiconductor device according to the fifth aspect of the present invention, the area of the metal penetrating portion parallel to the joint surface is 0.1% or more of the total area of the joint surface.

In a semiconductor device according to a sixth aspect of the present invention, the inert gas is nitrogen, carbon dioxide, a rare gas, hydrogen or carbon monoxide, or a mixed gas containing at least two of these gases, and the reducing property is The substance is mainly composed of an organic acid type flux, a polymer type flux or a mixture of these substances.

According to a seventh aspect of the present invention, there is provided a semiconductor device in which an oxygen adsorbent, a water vapor adsorbent, or both of these adsorbents are sealed together with a semiconductor chip.

In the semiconductor device according to the invention of claim 8, the inner wall of the base material is coated with titanium.

According to a ninth aspect of the semiconductor device of the present invention, the inner wall of the base material has a geometric shape for constraining the semiconductor chip.

In a semiconductor device according to a tenth aspect of the present invention, the base material or the semiconductor chip is provided with a heating device.

[0016]

In the semiconductor device according to the invention of claim 1, the semiconductor chip is bonded to the base material by a bonding metal having a melting point of less than 183 ° C., and the semiconductor chip is placed in contact with an inert gas or this bonding metal. Even if a failure such as a crack occurs in the joining metal due to the sealing with the conductive material, the crack can be repaired by heating the joining metal to a temperature of less than 183 ° C. to melt the joining metal.

A semiconductor device according to a second aspect of the present invention has a bonding metal containing lead, tin, bismuth, indium or antimony as a main component, or an alloy containing at least two or more of these metals as a main component. By doing so, it is possible to easily and reliably perform the joining with the joining metal.

According to a third aspect of the present invention, in the semiconductor device, the melting point of the central portion of the joining metal is 183 ° C. or higher,
The melting point other than this portion has a melting point of less than 183 ° C., and the semiconductor chip is sealed with an inert gas and a reducing substance arranged in contact with the bonding metal, so that the bonding metal in the portion other than the penetrating portion Even if a failure such as a crack occurs,
The crack can be repaired by heating to a temperature of less than 183 ° C. to melt the joining metal in the portion other than the penetrating portion without melting the penetrating portion.

In a semiconductor device according to a fourth aspect of the present invention, the bonding metal of the portion other than the penetrating portion contains lead, tin, bismuth, indium or antimony as a main component, or an alloy containing at least two or more of these metals. With the main component as the main component, and the lead-containing high melting point bonding metal
By using tin, indium, antimony, silver, gold, platinum, palladium, silicon or aluminum as a main component or an alloy containing at least two or more of these metals as a main component Can be easy and reliable.

In the semiconductor device according to the fifth aspect of the present invention, the area parallel to the joint surface in the metal penetrating portion is 0.1% or more of the total area of the joint surface, so that even if an external force acts on the semiconductor device. , It is possible to prevent the semiconductor chip from shifting or moving.

In a semiconductor device according to a sixth aspect of the present invention, the inert gas is nitrogen, carbon dioxide, a rare gas, hydrogen or carbon monoxide, or a mixed gas containing at least two of these gases, and the reducing property is reduced. By using a substance containing an organic acid-based flux, a polymer-based flux, or a mixture of these substances as a main component, it is possible to prevent an oxide film from existing on a fracture surface such as a crack generated in the joining metal.

In the semiconductor device according to the invention of claim 7, the oxygen adsorbent, the water vapor adsorbent, or both of these adsorbents are sealed together with the semiconductor chip.
Even if outside air containing oxygen and water vapor enters the sealed space, the oxide film can be prevented from existing on the fracture surface such as a crack generated in the bonding metal because it is adsorbed by these adsorbents.

In the semiconductor device according to the invention of claim 8, since the inner wall of the base material is coated with titanium, even if outside air containing oxygen enters the space in which the semiconductor chip is sealed,
Since oxygen is adsorbed by titanium, it is possible to prevent an oxide film from existing on a fracture surface such as a crack generated in the joining metal.

In the semiconductor device according to the invention of claim 9, the semiconductor chip is sealed by the base material having a geometrical shape for constraining the semiconductor chip, so that even if an external force acts on the semiconductor device. It can be prevented from slipping or moving.

According to a tenth aspect of the present invention, a semiconductor device is provided with a heating device on a base material or a semiconductor chip.
The cracked portion of the bonding metal can be melted without heating the entire substrate on which the semiconductor device is mounted.

[0026]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. 1 is a sectional view showing a semiconductor device according to a first embodiment of the present invention. Since the same reference numerals as those of the conventional one indicate the same or corresponding portions, the description thereof will be omitted. In the figure, 7 is a joining metal that joins the semiconductor chip 1 and the base material 2 and has a melting point of less than 183 ° C., for example, the composition is 49% Sn-41%.
A solder alloy having Pb-10% Bi and a melting point of 166 ° C. is used. Reference numeral 8 denotes an inert gas filled in the space in which the semiconductor chip 1 is sealed, for example, a rare gas such as argon gas is used. A metallizing process was performed on the bonding surface between the bonding metal 7 having a melting point of less than 183 ° C. and the semiconductor chip 1 and the bonding surface between the bonding metal 7 and the ceramic base material 2.

Next, the operation will be described. Melting point 166
When the semiconductor device having the bonding metal 7 having a temperature of 0 ° C. was repeatedly operated, cracks 6 were generated in the bonding metal 7 due to thermal stress. Therefore, the entire semiconductor device was heated in a reflow furnace set to a temperature of 170 ° C. to melt the joining metal 7. Since this semiconductor device is mounted on the substrate with Sn—Pb eutectic solder having a melting point of 183 ° C. like the one usually used, when it is heated at a temperature of less than 183 ° C. as in Example 1. The mounting joint is not destroyed. In this way, since the melted bonding metal 7 around the crack 6 has fluidity, the crack 6 was filled, and the bonding metal 7 was restored to the state before the crack 6 occurred. Further, since the bonding metal 7 is sealed in the space filled with the inert gas 8, the fracture surface of the crack 6 is clean without being oxidized, and therefore the crack 6 is easily bonded.

As described above, according to the first embodiment, the melting point of the bonding metal 7 for bonding the semiconductor chip 1 and the base material 2 is 18%.
By setting the temperature to be less than 3 ° C., the crack 6 generated in the bonding metal 7 can be repaired without damaging the mounting bonding portion only by heating the semiconductor device at a temperature lower than this temperature to the melting point of the bonding metal or higher. The semiconductor chip 1 is not limited to silicon, but may be a compound semiconductor such as gallium arsenide, and the same effect can be obtained even if the base material 2 is made of ceramics other than alumina, metal, resin, silicon, or the like. It goes without saying that it will be done.

Example 2. Although the case where the inert gas is sealed is shown in the above-mentioned Example 1, as shown in FIG.
The reducing substance 9 may be placed in contact with the bonding metal 7 while sealing the inert gas, and the same effect as that of the first embodiment can be obtained. In addition, as such a reducing substance, for example, an adhesive active rosin which is an organic acid-based flux is used. By repeatedly operating the semiconductor device, the semiconductor device having cracks 6 in the bonding metal 7 was heated in the same manner as in Example 1 to melt the bonding metal 7. Here, first, before the joining metal 7 is melted,
The activated rosin, which is a solid reducing substance 9, was melted by heating to obtain fluidity and penetrate into the crack 6 to cover the fracture surface of the crack 6 and positively reduce it. Next, the molten bonding metal 7 begins to fill the crack 6, and the reducing substance 9 covering the fracture surface of the crack 6 is excluded from the bonding metal 7, so that the reducing substance 9 that has penetrated into the crack 6 melts. The metal 7 is extruded to the outside. In this way, the crack 6 could be repaired.

As described above, according to the second embodiment, the reducing substance 9 positively reduces the fracture surface of the crack 6, so that the oxidation is prevented by the inert gas 8 only. The crack 6 can be easily and surely repaired. In addition, in Example 2, the reducing substance 9 was used together with the inert gas, but the same effect can be obtained even if only the reducing substance 9 is arranged in contact with the bonding metal 7 without using the inert gas. can get.

Example 3. In Example 1, the melting point is 183.
49% Sn-41% Pb-
Although the composition of 10% Bi is used, it is not limited to this as long as the metal has a melting point of less than 183 ° C., and lead, tin,
A material containing bismuth, indium or antimony as a main component or an alloy containing at least two or more of these metals as a main component may be used, and the same effect as that of the first embodiment can be obtained. In addition, this "main component" includes the above metal simple substance and the above alloy simple substance. In particular, it is possible to obtain a desired melting point by using a multi-component alloy.

Example 4. In the first embodiment, the joining metal 7
As shown in FIG. 3, a metal having a melting point of less than 183 ° C. is used. However, as shown in FIG. 3, the central penetrating part of the metal is a high melting point bonding metal having a melting point of 183 ° C. or higher, and the other parts are melting points. Of a bonding metal having a temperature of less than 183 ° C. may be used, and the same effect as that of the first embodiment can be obtained.

In FIG. 3, reference numeral 15 is a high melting point bonding metal having a melting point of 183 ° C. or more, which is disposed in the central penetrating portion of the metal for bonding the semiconductor chip 1 and the base material 2. As such a high melting point bonding metal 15, for example, 95% Pb-5%
A solder alloy having a Sn composition and a melting point of 310 ° C. is used. By repeatedly operating the semiconductor device, the semiconductor device having cracks 6 in the bonding metal 7 was heated in the same manner as in Example 1 to melt the bonding metal 7. The heating temperature (170 ° C.) at this time is the melting point of the high melting point bonding metal 15 (3
10 ° C.) or less, so the high melting point bonding metal 15 in the central portion
Does not melt, the crack 6 is repaired in the same manner as in Example 1 above, and the semiconductor chip 1 is firmly bonded to the base material 2 by the high melting point bonding metal 15.

As described above, according to the fourth embodiment, even if a failure such as a crack 6 occurs in the joining metal 7, the joining metal 7 is heated to a temperature lower than the melting point of the high melting point joining metal 15 and lower than 183 ° C. It goes without saying that the crack 6 can be repaired by melting the part of the joining metal 7 other than the part with the high melting point joining metal 15, and the high melting point joining metal 15 is different from the semiconductor chip 1 and the base material 2 in the first embodiment. Because it is joined more firmly,
During the heating for repairing the crack 6, the semiconductor chip 1 does not shift or move even if an external force such as vibration acts on the semiconductor device.
It is possible to prevent inconvenience such as disconnection.

Since the thermal stress acting on the joint between the semiconductor chip 1 and the base material 2 is maximized in the outer peripheral portion, the crack 6 always occurs from the outer peripheral portion of the joint metal 7 and propagates inward. . Therefore, the crack 6 does not reach the high-melting-point bonding metal 15 in the central portion of the bonding portion, and the surrounding bonding metal 7
If the cracks are repaired while existing only in the cracks, the cracks 6 can be completely joined and repaired as in the first embodiment.

Example 5. In Example 4, the melting point is 18
49% Sn-41% Pb-as the joining metal 7 below 3 ° C
Although the composition of 10% Bi is used, it is not limited to this as long as the metal has a melting point of less than 183 ° C., and lead, tin,
A material containing bismuth, indium or antimony as a main component or an alloy containing at least two or more of these metals as a main component may be used. In addition, this "main component" includes the above metal simple substance and the above alloy simple substance. Further, a solder alloy having a composition of 95% Pb-5% Sn and a melting point of 310 ° C. was used as the high melting point bonding metal 15, but the present invention is not limited to this as long as the metal has a melting point of 183 ° C. or more, and lead, A material containing tin, indium, antimony, silver, gold, platinum, palladium, silicon or aluminum as a main component or an alloy containing at least two or more of these metals as a main component may be used. In addition, this "main component" includes the above-mentioned simple metals having a melting point of 183 [deg.] C. or higher and the above-mentioned simple alloys. By using the metals as described above, the same effect as that of the above-described fourth embodiment can be obtained. In particular, it is possible to obtain a desired melting point by using a multi-component alloy.

Here, the ratio of the area parallel to the joint surface of the high melting point joint metal 15 disposed in the central portion of the joint portion between the semiconductor chip 1 and the base material 2 to the total area of the joint surface is 1 from the outside.
Assuming that a shock of 000 G is applied, 0.1% or more is desired from the following formula. Density of semiconductor chip D = 2.34 × 10 ⁻³ (g / mm ³ ) Thickness of semiconductor chip T = 1 (mm) Area of semiconductor chip A = 100 (mm ² ) Tensile strength of high melting point bonding metal 15 S = Assuming 2000 (g / mm ² ), the stress F applied to the high melting point bonding metal 15 is F = D × T × A × 1000 = 234 (g), and the area B of the high melting point bonding metal 15 that can withstand this stress. Is B = F / S = 0.1 (mm ² ). Therefore, the ratio R of the area of the joining portion of the high melting point joining metal 15 to the entire area of the semiconductor chip 1 is R = B / A = 0.1 (%).

Example 6. Although the case where the sealed space of the semiconductor chip 1 is filled with argon has been shown in the above-mentioned Example 1, the present invention is not limited to this as long as it is an inert gas, and nitrogen, carbon dioxide, a rare gas, hydrogen or It may be filled with carbon monoxide or a mixed gas containing at least two or more of these gases, and the same effect as that of the first embodiment can be obtained.

Example 7. In Example 2 above, the reducing substance 9
Although the case where activated rosin, which is an organic acid-based flux, is used as an example, any substance that does not cause damage such as corrosion to the semiconductor chip 1, the base material 2, the bonding wires 5, the leads 4, etc. may be used. Other than acid flux,
For example, a polymer-based flux can be used, and the same effect as in Example 2 can be obtained.

Example 8. In the first embodiment, the joining metal 7
In order to prevent the oxidation of the fractured surface of the crack 6 generated in the above, the case where the space in which the semiconductor chip 1 is sealed is filled with argon is shown. As shown in FIG. However, the same effect as that of the first embodiment can be obtained.

In the figure, 10 is an oxygen adsorbent. The method of repairing the crack 6 generated in the bonding metal 7 during the repeated operation of the semiconductor device is the same as that of the above-described first embodiment, but the base material 2 is not completely sealed, and, for example, a semiconductor filled with argon gas 8 is used. Even when outside air enters the space where the chip 1 is sealed, the oxygen adsorbent 10 preferentially consumes oxygen and cracks 6
Oxidation of the fracture surface can be prevented. Therefore, since an oxide film is not formed on this fractured surface and it is kept clean, the crack 6 can be easily joined and repaired.

As described above, according to the eighth embodiment, by using the oxygen adsorbent 10, the fracture surface of the crack 6 is kept cleaner than in the first embodiment, so that the crack 6 can be repaired more easily. be able to. In addition, although the case where the oxygen adsorbent is sealed is shown in this Example 8, the same effect can be obtained when the steam adsorbent is used or both the oxygen adsorbent and the steam adsorbent are sealed. Needless to say.

Embodiment 9 FIG. In the first embodiment, the joining metal 7
In order to prevent the oxidation of the fracture surface of the crack 6 generated in the above, the case where the space in which the semiconductor chip 1 is sealed is filled with argon is shown. In addition to this, as shown in FIG. The base material 2 coated with 11 may be used, and the same effect as that of the first embodiment can be obtained.

In the figure, 11 is a titanium coating 11 applied to the inner surface of the base material 2, and a titanium film formed by vacuum vapor deposition, for example, is used. The method for repairing the crack 6 generated in the bonding metal 7 during the repeated operation of the semiconductor device is the same as in the first embodiment. Incomplete sealing of the base material 2,
For example, even if outside air enters the space in which the semiconductor chip 1 filled with the argon gas 8 is sealed, the titanium coating 1
Since 1 adsorbs oxygen by the gettering effect, oxidation of the fracture surface of the crack 6 can be prevented. Therefore, since an oxide film is not formed on this fractured surface and it is kept clean, the crack 6 can be easily joined and repaired.

As described above, according to the ninth embodiment, since the base material 2 coated with the titanium film 11 is used,
Since the fracture surface of the crack 6 is kept cleaner than in the first embodiment, the crack 6 can be easily repaired.

Example 10. In the fourth embodiment, in order to prevent the semiconductor chip 1 from being displaced or moved by an external force such as vibration while the semiconductor device is being heated, and the bonding wire 5 from being cut, the melting point is set in the central portion of the bonding metal 7. Although the case where a high melting point bonding metal of 183 ° C. or higher is used is shown, as shown in FIGS. 6 to 8, a base material having a geometric shape for constraining the semiconductor chip 1 on the inner wall may be used.
The same effect as that of the fourth embodiment can be obtained.

In the figure, reference numerals 12, 13 and 14 denote base materials having on their inner walls a geometrical shape for restraining the semiconductor chip 1. The geometric shape is not particularly limited as long as it constrains the semiconductor chip 1 from the left-right direction and the vertical direction. The gap between the semiconductor chip 1 and the base material 2 is set to 1 mm or less in both the horizontal direction and the vertical direction. The method for repairing the crack 6 generated in the bonding metal 7 during the repeated operation of the semiconductor device is the same as that in the above-described fourth embodiment, but the semiconductor device is heated during the heating for repairing the crack 6 generated in the bonding metal 7, for example. Even if an external force such as vibration is applied, the semiconductor chip 1 is not
The movement is restrained by.

As described above, according to the tenth embodiment, since the semiconductor chip 1 is constrained by the geometrical shape of the inner wall of the base material, the high melting point bonding metal is used as in the fourth embodiment. Without this, the semiconductor chip 1 can be prevented from being displaced or moved, and the inconvenience such as cutting of the bonding wire 5 can be prevented.

Example 11. Although the reflow furnace device is used to heat the semiconductor device in the first embodiment, a base material 2 provided with a heating device as shown in FIG. 9 may be used, and the same effect as in the first embodiment is obtained. be able to.

In the figure, 16 is a heating device, and for example, a thin film heater or the like can be used. The crack 6 generated in the bonding metal 7 during repeated operation of the semiconductor device is
The bonding portion is heated by a thin film heater, which is a heating device 16 disposed inside, to melt and repair the bonding metal 7.

As described above, according to the eleventh embodiment, it is not necessary to heat the entire substrate on which the semiconductor device is mounted, and only the semiconductor device can be selectively heated. Compared to Example 1, less energy is required for heating and the device can be made compact. Although the heating device 16 is installed in the base material 2 in the eleventh embodiment, the same effect can be obtained by installing the heating device 16 in the semiconductor chip 1.

In the above examples 1 to 11, the case of so-called die bonding in which the entire back surface of the semiconductor chip 1 is bonded to the base material 2 is shown. However, so-called flip-chip bonding shown in FIG. In this case, the same effect can be obtained.

[0053]

As described above, according to the invention of claim 1,
A semiconductor chip is bonded to a base material with a bonding metal having a melting point of less than 183 ° C., and the semiconductor chip is sealed together with at least one of an inert gas and a reducing substance arranged in contact with the bonding metal. Therefore, even if a failure such as a crack occurs in the bonding metal, there is an effect that the crack can be repaired without damaging the mounting bonding portion by heating the bonding metal to a temperature of less than 183 ° C to melt the bonding metal.

According to the invention of claim 2, the joining metal is lead,
Since the main component is tin, bismuth, indium, or antimony, or the alloy containing at least two or more of these metals, it is possible to easily and surely bond with the bonding metal. There is an effect that can be.

According to the third aspect of the present invention, of the metal, the through portion of the central portion including both the bonding surface with the semiconductor chip and the base material is a high melting point bonding metal having a melting point of 183 ° C. or higher, and the other portions than the through portion. Since the portion is composed of a bonding metal having a melting point of less than 183 ° C., and the semiconductor chip is configured to be sealed together with at least one of an inert gas and a reducing substance arranged in contact with the bonding metal. , Even if a failure such as a crack occurs in the joining metal other than the penetration portion, the joining metal of the portion other than the penetration portion is melted by heating to a temperature of less than 183 ° C without melting the penetration portion. This crack can be repaired. Therefore,
During heating for repairing cracks, for example, even if an external force such as vibration acts on the semiconductor device, the semiconductor chip does not shift or move, and it is possible to prevent inconvenience such as cutting of the bonding wire.

According to the invention of claim 4, the bonding metal of the portion other than the penetrating portion is mainly composed of lead, tin, bismuth, indium or antimony, or an alloy containing at least two or more of these metals. The main component is a high melting point bonding metal in the penetrating portion, which contains lead, tin, indium, antimony, silver, gold, platinum, palladium, silicon or aluminum as the main component, or at least two or more of these metals. Since the main component is the alloy containing, there is an effect that the joining by the metal can be performed easily and surely.

According to the fifth aspect of the invention, the area parallel to the joint surface in the metal penetration portion is set to 0.
Since it is configured to be 1% or more, it is possible to prevent the semiconductor chip from shifting or moving even when an external force is applied to the semiconductor device, and it is possible to prevent inconveniences such as cutting of the bonding wire 5.

According to the invention of claim 6, the inert gas is nitrogen, carbon dioxide, a rare gas, hydrogen or carbon monoxide or a mixed gas containing at least two or more of these gases, and the reducing substance is The organic acid flux, polymer flux, or a mixture of these substances is used as the main component, so it is possible to prevent the oxide film from existing on the fracture surface such as cracks in the joining metal. There is an effect that joining with a metal can be performed easily and surely.

According to the invention of claim 7, since the oxygen adsorbent, the water vapor adsorbent, or both of these adsorbents are sealed together with the semiconductor chip, the sealed space contains oxygen or water vapor. Even if outside air invades, it is possible to prevent the oxide film from existing on the fracture surface such as a crack generated in the joining metal because it is adsorbed by these adsorbents, so that the effect of easily and reliably joining with the joining metal is obtained. is there.

According to the eighth aspect of the present invention, since the inner wall of the base material is coated with titanium, even if the outside air containing oxygen enters the space in which the semiconductor chip is sealed, the oxygen is still supplied by the titanium. Since it is possible to prevent oxidation of the fracture surface such as a crack generated in the joining metal due to the adsorption of the, it is possible to easily and surely join with the joining metal.

According to the ninth aspect of the invention, since the inner wall of the base material is provided with a geometrical shape for restraining the semiconductor chip, the semiconductor chip does not shift or move even when an external force is applied to the semiconductor device. In addition to this, there is an effect that it is possible to prevent inconvenience such as cutting of the bonding wire.

According to the tenth aspect of the present invention, since the base material or the semiconductor chip is provided with the heating device, the cracked portion of the bonding metal is melted without heating the entire substrate on which the semiconductor device is mounted. It is effective in repairing cracks generated in the joining metal.

[Brief description of drawings]

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

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

FIG. 3 is a sectional view showing a configuration of a semiconductor device according to a fourth embodiment of the present invention.

FIG. 4 is a sectional view showing a structure of a semiconductor device according to an eighth embodiment of the present invention.

FIG. 5 is a sectional view showing a structure of a semiconductor device according to a ninth embodiment of the present invention.

FIG. 6 is a sectional view showing the structure of a semiconductor device according to Example 10 of the present invention.

FIG. 7 is a sectional view showing a structure of a semiconductor device according to a tenth embodiment of the present invention.

FIG. 8 is a sectional view showing a structure of a semiconductor device according to a tenth embodiment of the present invention.

FIG. 9 is a sectional view showing a structure of a semiconductor device according to an eleventh embodiment of the present invention.

FIG. 10 is a sectional view showing a configuration of a semiconductor device by flip chip bonding according to the present invention.

FIG. 11 is a sectional view showing a configuration of a conventional semiconductor device.

[Explanation of symbols]

1 semiconductor chip, 2 base material, 7 bonding metal, 8 inert gas, 9 reducing substance, 10 oxygen adsorbent, 11 titanium coating, 15 high melting point bonding metal, 16 heating device.

Claims (10)

[Claims] 1. A semiconductor device in which a semiconductor chip is bonded to a base material by a bonding metal, wherein the melting point of the bonding metal is less than 183 ° C., and the semiconductor chip is placed in contact with an inert gas and the bonding metal. A semiconductor device, which is encapsulated with at least one of the reducing substances described above. 2. The bonding metal is mainly composed of lead, tin, bismuth, indium or antimony, or is mainly composed of an alloy containing at least two kinds of these metals. The semiconductor device according to claim 1. 3. In a semiconductor device in which a semiconductor chip is bonded to a base material by a metal, a melting point of a central portion of the metal including both bonding surfaces of the semiconductor chip and the base material has a melting point of 183 ° C. or higher. The melting point bonding metal is formed of a bonding metal having a melting point of less than 183 ° C. other than the penetrating portion, and the semiconductor chip includes at least one of an inert gas and a reducing substance disposed in contact with the bonding metal. A semiconductor device, which is sealed together with one side. 4. The joining metal of the portion other than the penetrating portion,
The main component is lead, tin, bismuth, indium or antimony, or an alloy containing at least two of these metals. A material containing at least indium, indium, antimony, silver, gold, platinum, palladium, silicon or aluminum as a main component or an alloy containing at least two or more of these metals as a main component. 3. The semiconductor device according to item 3. 5. The semiconductor device according to claim 3, wherein an area of the metal penetrating portion parallel to the joint surface is 0.1% or more of the total area of the joint surface. 6. The inert gas is nitrogen, carbon dioxide,
It is a rare gas, hydrogen, carbon monoxide, or a mixed gas containing at least two or more of these gases, and the reducing substance contains an organic acid flux, a polymer flux, or a mixture of these substances as a main component. The semiconductor device according to claim 1, wherein the semiconductor device is a semiconductor device. 7. The semiconductor device according to claim 1, wherein the oxygen adsorbent, the water vapor adsorbent, or both of these adsorbents are sealed together with the semiconductor chip. 8. The semiconductor device according to claim 1, wherein an inner wall of the base material is coated with titanium. 9. The semiconductor device according to claim 1, wherein an inner wall of the base material has a geometric shape for constraining a semiconductor chip. 10. The base material or the semiconductor chip comprises:
10. The semiconductor device according to claim 1, further comprising a heating device.