JPH0917904A - Wiring board and semiconductor device receiving package using it and packaging structure thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a strong and stable connection state for a long term by using a sintered material, having a specific value of a linear thermal expansion coefficient at a temperature in a specific range, produced by baking a molded body containing a filler in a ratio within a specific of value, which filter containing a metal oxide whose linear thermal expansion coefficient is not less than a specific value. SOLUTION: As an insulating board for a package, a molded body containing 20-80volume% of lithium silicic acid glass having 5-30weight% of Li2 O and a yielding point of 400 deg.C-800 deg.C and 80-20volume% of a filler containing a metal oxide whose linear thermal expansion coefficient is not less then 6ppm/ deg.C at 40 deg.C-400 deg.C, is sintered. Further, by using the sintered body having a linear thermal expansion coefficient of 8-18ppm/ deg.C at 40 deg.C-400 deg.C, the linear thermal expansion coefficient of the sintered body can easily be controlled in the range of 8-18ppm/ deg.C and the sintered body can be manufactured with improved reproducibility. Thus, the semiconductor device received in the container can be electrically connected accurately and strongly for a long term.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board having a metallized wiring layer, a semiconductor device package having the wiring board, and a mounting structure thereof.

[0002]

2. Description of the Related Art Conventionally, a wiring board has a structure in which a metallized wiring layer is disposed on the surface or inside of an insulating substrate.
Further, as a typical example using this wiring board, a semiconductor element housing package for housing a semiconductor element, particularly a semiconductor integrated circuit element such as an LSI (Large Scale Integrated Circuit Element) is generally made of an electrical material such as alumina ceramics. An insulating substrate made of an insulating material and having a recess for accommodating a semiconductor element in the center of its upper surface, and a plurality of refractory metal powders such as tungsten and molybdenum that are led out from the periphery of the recess of the insulating substrate to the lower surface. Individual metallized wiring layers,
It is composed of a plurality of connection pads formed on the lower surface of the insulating substrate and electrically connected to the metallized wiring layer, connection terminals brazed and attached to the connection pads, and a lid. The semiconductor element is glass on the bottom of the recess of the substrate,
The electrodes of the semiconductor element and the metallized wiring layer are electrically connected to each other through a bonding wire, and the lid is attached to the upper surface of the insulating substrate by a sealing material such as glass or resin. The semiconductor element as a product is packaged by bonding the semiconductor element through the above, and hermetically sealing the semiconductor element inside the container composed of the insulating substrate and the lid.

In order to connect the semiconductor element housing package to the wiring conductor of the external electric circuit board, the connection terminals connected to the connection pads on the lower surface of the insulating board of the semiconductor element housing package and the external electric circuit board are connected. The wiring conductor can be electrically connected by soldering or the like.

Generally, as the degree of integration of a semiconductor element increases, the number of electrodes formed on the semiconductor element also increases, but along with this, the number of terminals in a semiconductor housing package for housing the same also increases. However, there is a limit to increase the size of the package itself as the number of electrodes increases, and it is necessary to increase the density of terminals in the package because further miniaturization is required.

As a structure for increasing the density of terminals in a conventional package, a pin grid array (P) in which metal pins such as Kovar are connected to the lower surface of the package is used.
GA) is the most common, but recently, a quad flat package (QFP) of the type in which gull wing-shaped (L-shaped) metal pins are connected to metallized wiring layers led out on four sides of the package, package There is a leadless chip carrier (LCC) that has electrode pads on the four side surfaces, and a ball grid array (BGA) in which a large number of spherical terminals made of solder are arranged on the lower surface of an insulating substrate. Is said to be the highest density possible.

In this ball grid array (BGA), a spherical terminal made of a brazing material such as solder is brazed to a connection pad, and the spherical terminal is placed and abutted on a wiring conductor of an external electric circuit board. After that, the terminals are heat-melted at a temperature of about 250 to 400 ° C., and the spherical terminals are joined to the wiring conductors to be mounted on the external electric circuit board. With such a mounting structure, each electrode of the semiconductor element housed inside the semiconductor element housing package is electrically connected to the external electric circuit through the metallized wiring layer and the connection terminal.

Further, as an insulating substrate in a package for housing a semiconductor element, an insulating material made of a sintered body such as glass-ceramic is mainly used.

For example, Japanese Patent Laid-Open No. 63-117929 proposes a glass ceramic body using ZnO--Al ₂ O ₃ --SiO ₂ glass. According to such a publication, the chemical composition and heat treatment conditions are set. It has been reported that the coefficient of linear thermal expansion can be controlled by producing crystals of cordierite or zinc pebbles in addition to zinc silicate by controlling the.

[0009]

Ceramics such as alumina and mullite used as an insulating substrate in these packages have a high strength of 200 MPa or more and are reliable as a multi-layering technology with a metallized wiring layer. Although it is useful because of its high thermal conductivity, its coefficient of linear thermal expansion is approximately 4 to 7 ppm / ° C, while it is used as the glass-epoxy insulating layer that is most often used as an external electric circuit board on which a package is mounted. The linear thermal expansion coefficient of the printed circuit board on which the Cu wiring layer is formed is 11 to 18 ppm / ° C.
And very big.

Therefore, when the semiconductor integrated circuit element is housed inside the semiconductor element housing package and then mounted on an external electric circuit board such as a printed circuit board, the heat generated during the operation of the semiconductor integrated circuit element acts as an insulating substrate. When repeatedly applied to both the external electric circuit board, a large thermal stress is generated between the insulating board and the external electric circuit board due to the difference in linear thermal expansion coefficient between the two. This thermal stress has no significant effect when the number of terminals in the package is relatively small, such as 300 or less, but the effect tends to increase as the number of terminals exceeds 300 and the package itself becomes larger. That is, when thermal stress is repeatedly applied by repeating the operation and stop of the package, this thermal stress acts on the outer peripheral portion of the connection pad on the lower surface of the insulating substrate and the bonding interface between the wiring conductor and the terminal of the external electric circuit board. As a result, the connection pad may be peeled off from the insulating substrate or the terminal may be peeled off from the wiring conductor, so that the connection terminal of the package for housing the semiconductor element can be stably electrically connected to the wiring conductor of the external electrode circuit for a long time. It had the drawback of not being able to.

Further, although it has been reported that a substrate having a high coefficient of linear thermal expansion can be obtained in the integrated circuit package substrate using a glass ceramic body disclosed in Japanese Patent Laid-Open No. 63-117929, as described in the publication. Even with the same composition, the precipitated crystal phase changes due to slight differences in heat treatment conditions, making it difficult to control the linear thermal expansion coefficient in a stable manner. Moreover, since expensive crystalline glass is used, the package can be manufactured inexpensively. It cannot be done.

In general, borosilicate glass is most used as a glass used for producing a glass-ceramic sintered body, but this borosilicate glass is sintered because of its relatively high yield point. Therefore, it is necessary to use glass as a main component. Therefore, in the case of firing at a low temperature, there is a problem that the manufacturing cost becomes high because a large amount of expensive glass is required. In addition, there are cases where debinding and sintering are not sufficiently performed, and therefore, it was necessary to finely control the composition of glass and the filler.

Further, according to the wiring board and the package for accommodating semiconductor elements, the insulating substrate and the metallized wiring layer provided inside and on the surface of the insulating substrate are simultaneously fired. At present, there is no study on co-firing with a substrate.

Therefore, the present invention provides a wiring board having a metallized wiring layer on the surface or inside of an insulating substrate having a high thermal expansion characteristic, and a semiconductor element storage package having a high thermal expansion characteristic and storing a semiconductor element. An object of the present invention is to provide a highly reliable package for housing a semiconductor element, which can maintain a stable and stable connection state for a long time with respect to an external electric circuit using glass-epoxy resin or the like as an insulator, and a mounting structure thereof. To do.

Furthermore, a high-quality and inexpensive wiring board and semiconductor capable of co-firing with a Cu metallized wiring layer, capable of efficiently removing a binder and sintering at a low temperature even with a relatively small amount of glass. An object is to provide a package for storing elements.

[0016]

As a result of repeated studies on the above problems, the inventors of the present invention found that Li ₂ was used as an insulating substrate.
Lithium silicate glass containing 5 to 30% by weight of O stably deposits lithium silicate crystals with a linear thermal expansion coefficient of 13 ppm / ° C in the sintering process. By adding a compound having a coefficient and firing it, a sintered body having a high thermal expansion can be produced, and lithium silicate glass has a relatively low yield point as compared with borosilicate glass, and as a result,
The inventors have found that low-temperature firing is possible even when the amount of glass added is small, and completed the present invention.

That is, according to the present invention, in a wiring board in which a metallized wiring layer is provided on the surface or inside of the insulating substrate, the insulating substrate contains 5 to 30% by weight of Li ₂ O and the yield point is 400 ° C. A molded body containing 20 to 80% by volume of lithium silicate glass at ˜800 ° C. and 80 to 20% by volume of a filler containing a metal oxide having a linear thermal expansion coefficient at 40 ° C. to 400 ° C. of 6 ppm / ° C. or more. Baked 4
Coefficient of linear thermal expansion at 0 ° C to 400 ° C is 8 to 18 ppm
It is characterized by comprising a sintered body of / ° C.

Also, as an insulating substrate in a package for accommodating semiconductor elements, it contains 5 to 30% by weight of Li ₂ O,
2 lithium silicate glass with a yield point of 400 ℃ ~ 800 ℃
40 degreeC which baked the molded object which contains 0-80 volume% and the filler containing the metal oxide whose linear thermal expansion coefficient in 40 degreeC-400 degreeC is 6 ppm / degreeC or more at 80-20 volume% 40 degreeC.
Linear thermal expansion coefficient at ~ 400 ° C is 8-18ppm / ° C
It is composed of a sintered body.

Further, according to the present invention, for storing a semiconductor element, the above-mentioned sintered body is provided as an insulating substrate on an external electric circuit board having a wiring conductor formed on the surface of an insulating body containing at least an organic resin. The package is mounted by brazing and connecting to the wiring conductor of the circuit board via the connection terminal.

[0020]

According to the present invention, as a wiring substrate or an insulating substrate for a semiconductor element housing package, 20 to 20% of lithium silicate glass containing 5 to 30% by weight of Li ₂ O and having a yield point of 400 to 800 ° C is used. Linear heat at 40 ° C to 400 ° C obtained by firing a molded body containing 80% by volume and a filler containing a metal oxide having a linear thermal expansion coefficient at 40 ° C to 400 ° C of 6 ppm / ° C or more at a ratio of 80 to 20% by volume. Expansion coefficient is 8 to 1
By using the sintered body of 8 ppm / ° C., the linear thermal expansion coefficient of the sintered body can be easily controlled within the range of 8 to 18 ppm / ° C., and the product can be reproducibly manufactured. Further, by using lithium silicate glass containing Li ₂ O as an essential component in an amount of 5 to 30 wt% as the above glass, high thermal expansion of lithium silicate (for example, Li ₂ SiO ₃ ) can be deposited.

Further, the yield point of lithium silicate glass is set to 4
By setting the temperature to 00 ° C. to 800 ° C., the glass content can be reduced and the filler can be increased, and the firing shrinkage start temperature can be increased. Thereby,
It is possible to efficiently remove the molding binder such as an organic resin added at the time of molding, and to match the firing conditions with the metallization that is fired at the same time as the insulating substrate.

Further, the coefficient of linear thermal expansion of the lithium silicate crystal phase precipitated from the lithium silicate glass is about 13 ppm / ° C.
To easily control the linear thermal expansion coefficient of the entire sintered body in the range of 8 to 18 ppm / ° C by adding a filler containing a metal oxide having a linear thermal expansion coefficient of 6 ppm / ° C or higher at 0 ° C to 400 ° C. Can be done.

As described above, as an insulating substrate in a package for accommodating semiconductor elements mounted on an external electric circuit formed of a printed circuit board such as a glass-epoxy substrate, 4
The linear thermal expansion coefficient in the temperature range of 0 to 400 ° C is 8 to 1
By using the ceramics of 8 ppm / ° C., the difference in linear thermal expansion coefficient between the insulating substrate and the external electric circuit substrate becomes small, and as a result, the difference in linear thermal expansion coefficient between the insulating substrate and the external electric circuit substrate. The terminal does not cause a connection failure between the terminal and the wiring conductor of the external electric circuit due to the thermal stress, which also ensures that the semiconductor element housed inside the container and the external electric circuit can be accurately and firmly electrically connected for a long period of time. It becomes possible to make a physical connection.

Further, since the linear thermal expansion coefficient of Cu used as the internal wiring of the package is approximately 18 ppm / ° C., the reliability of the adhesion of the metallized wiring to the substrate is improved. be able to.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings showing an embodiment. FIG. 1 and FIG. 2 are views showing an embodiment of a package for housing a BGA type semiconductor device and a mounting structure thereof according to the present invention. This package has a metallized wiring layer provided on the surface or inside an insulating substrate. In addition, a so-called wiring board has a basic structure, A indicates a package for housing a semiconductor element, and B indicates an external electric circuit board.

The semiconductor element housing package A is composed of an insulating substrate 1, a lid 2, a metallized wiring layer 3, terminals 4 and a semiconductor element 5 housed inside the package. The insulating substrate 1 and the lid 2 are semiconductors. A container 6 for hermetically housing the element 5 therein is configured. That is, the insulating substrate 1 has a recess 1 in which the semiconductor element 5 is placed and housed in the center of the upper surface.
a is provided, and the semiconductor element 5 is bonded and fixed to the bottom surface of the recess 1a through an adhesive such as glass or resin.

On the insulating substrate 1, a plurality of metallized wiring layers 3 are adhered and formed from the periphery of the concave portion 1a in which the semiconductor element 5 is mounted and accommodated to the lower surface. As shown in FIG. 2, a large number of recesses 1b are provided, and connection pads 3a electrically connected to the metallized wiring layer 3 are adhered to the bottom surface of the recesses 1b. Solder (tin-lead alloy) is formed on the surface of the connection pad 3a.
A protruding terminal 4 made of a brazing material such as is attached as a connection terminal 4 to the external electric circuit board. As a method of mounting the protruding terminals 4, there are a method of arranging a spherical or columnar brazing material on the connection pad 3a and a method of printing the brazing material on the connection pad by a screen printing method.

The connection terminal 4 attached to the connection pad 3a has a protrusion 4a on the lower surface of the insulating substrate 1,
Connection pad 3a to which each electrode of the semiconductor element 5 is connected
Is connected to the wiring conductor 8 of the external electric circuit board B, and the semiconductor element housing package A is connected to the external electric circuit board B.
It has the effect of being mounted on top.

The metallized wiring layer 3 electrically connected to the connection pads 3a is electrically connected to each electrode of the semiconductor element 5 through the bonding wires 7, so that the electrodes of the semiconductor element are connected to each other. It will be electrically connected to the pad 3a. In the external electric circuit board B, the wiring conductor 8 is formed on the surface of the insulator 9.

On the other hand, the external electric circuit board B is composed of an insulator 9 and a wiring conductor 8, and the insulator 9 is a printed circuit board made of a material containing at least an organic resin. Specifically, the linear thermal expansion coefficient at 40 to 400 ° C. is 12 to 16 like glass-epoxy composite materials.
It is composed of an insulating material of ppm / ° C. Also, this circuit board B
The wiring conductor 8 formed on the surface of the copper is usually made of Cu, A or the like in terms of the matching of the coefficient of linear thermal expansion with the insulator and the good electrical conductivity.
It is made of a metal conductor such as u, Al, Ni, or Pb—Sn.

In order to mount the package A for accommodating semiconductor elements on the external electric circuit board B, the insulating substrate 1 of the package A is used.
The projecting terminals 4 made of solder attached to the connection pads 3a on the lower surface are placed and abutted on the wiring conductors 8 of the external electric circuit board B, and then heated at a temperature of about 250 to 400 ° C. As a result, the protruding terminal 4 itself made of a brazing material such as solder is melted, and the terminal 4 is joined to the wiring conductor 8 to be mounted on the external electric circuit board B. At this time,
It is desirable that a brazing material is adhered to the surface of the wiring conductor 8 in order to easily connect the terminal 4 with the brazing material.

As another example, as shown in FIG. 3, a spherical terminal 10 made of a high melting point material is brazed to the connection pad 3a by a low melting point brazing material 11 as the connection terminal. This high melting point material needs to have a higher melting point than the low melting point brazing material used for brazing, and the brazing brazing material is, for example, Pb 40 wt% -Sn.
In the case of being composed of a solder having a low melting point of 60% by weight, the spherical terminal may be, for example, a solder having a high melting point of 90% by weight of Pb and 10% by weight of Sn,
It is composed of a metal such as Cu, Ag, Ni, Al, Au, Pt, and Fe.

In such a structure, the spherical terminal 10 attached to the connection pad 3a on the lower surface of the insulating substrate 1 of the package A is placed and abutted on the wiring conductor 8 of the external electric circuit board B, and then the spherical terminal is attached. 10 can be mounted on the external electric circuit board B by adhering it to the wiring conductor 8 with a brazing material 12 such as solder. Au is used as a low melting point brazing material.
The connection terminal may be connected to the external electric circuit board using —Sn alloy, and a columnar terminal may be used instead of the spherical terminal.

Next, the mounting structure of the leadless chip carrier (LCC) type package C on the external transmission circuit board B will be described with reference to FIG. In FIG. 4, the same members as those in FIG. 1 are denoted by the same reference numerals. In the package C in FIG. 4, the metallized wiring layers 3 individually connected to the electrodes of the semiconductor element are led out to four side surfaces of the insulating substrate 1, and the metallized wiring layers led to the side surfaces are connected to the connection terminals 4.
Is composed. Further, according to this package C, in order to prevent electromagnetic interference, the recess 1a for housing the semiconductor element 5 is filled with epoxy resin or the like, and the recess is sealed by the lid 13 made of a conductive resin. Further, a conductive layer 14 for grounding is formed on the bottom surface of the package C.

To mount the package C on the external electric circuit board B, the connecting terminals 4 on the side surface of the insulating substrate 1 of the package C are placed on and abutted on the wiring conductors 8 of the external electric circuit board B, and brazing material or the like is used. To electrically connect. At this time, the connection terminals 4 are desirably coated with a brazing material on the surface of the wiring conductor 8 in order to facilitate connection with the brazing material.

(Material of Insulating Substrate) According to the present invention, the insulating substrate 1 is 40 to 4 as a package for accommodating semiconductor elements mounted on the surface of such an external electric circuit board B.
The linear thermal expansion coefficient in the temperature range of 00 ° C is 8 to 18 pp
It is important that the sintered body has m / ° C, especially 9 to 14 ppm / ° C. This is important for alleviating the generation of thermal stress due to the difference in thermal expansion between the external electric circuit board B and the electrical connection state between the external electric circuit board B and the package A maintained for a long period of time. And the coefficient of linear thermal expansion is less than 8 ppm / ° C, or 18 pp
If it is larger than m / ° C., the thermal stress due to the difference in thermal expansion becomes large, and it is impossible to prevent deterioration of the electrical connection state between the external electric circuit board B and the package A.

The thermal expansion coefficient of the insulating substrate is 8 to 18 p.
With the increase in pm / ° C., the difference in thermal expansion between the semiconductor element and the semiconductor element using Si as the substrate increases. Therefore, as the adhesive material, it is necessary to appropriately select an adhesive material for the insulating substrate of the semiconductor element so that the semiconductor element does not peel off due to the difference in thermal expansion. Desirably, the adhesive is made of a flexible material capable of buffering the difference in thermal expansion. For example, an organic adhesive such as an epoxy-based or polyimide-based adhesive, or in some cases, a metal such as Ag is blended. Those are preferably used.

According to the present invention, as a sintered body constituting the insulating substrate having such a high linear thermal expansion coefficient, a molded body containing 20 to 80% by volume of crystalline glass and 80 to 20% by volume of a filler component. It is composed of a sintered body obtained by firing. The amount of the crystalline glass and the filler component is limited to the above range because the amount of the crystalline glass component is less than 20% by volume, in other words, the filler component is 80% by volume.
If the amount is larger, liquid phase sintering cannot be performed and it is necessary to fire at a high temperature. In that case, the metallization melts in the metallization simultaneous firing. Also, the crystalline glass is 80
If the content of the filler is more than 20% by volume, that is, if the content of the filler is less than 20% by volume, the properties of the sintered body largely depend on the properties of the crystalline glass, making it difficult to control the material properties and lowering the sintering start temperature. Therefore, there arises a problem that it cannot be fired at the same time as the wiring conductor. Also, the cost of the raw material increases.

As the crystallizable glass, it is important to use a lithium silicate glass containing 5 to 30% by weight, particularly 5 to 20% by weight of Li ₂ O, and such a lithium silicate glass is used. By using it, lithium silicic acid having a high coefficient of thermal expansion can be deposited. If the content in Li ₂ O is lower than 5% by weight, the amount of lithium silicic acid crystals produced during firing will be small and high thermal expansion cannot be achieved. If the content is higher than 30% by weight, the dielectric loss tangent will be 100.
Since it exceeds × 10 ^-4 , the characteristics as a substrate deteriorate.
Further, it is desirable that Pb is not substantially contained in this glass. This is because Pb is toxic and requires a special apparatus and control for preventing poisoning during the manufacturing process, so that the sintered body cannot be manufactured at low cost. Considering the case where Pb is unavoidably mixed as an impurity, the amount of Pb is preferably 0.05% by weight or less.

Further, the yield point of crystalline glass is 400 ° C.
It is also necessary that the temperature is from 800 to 800C, especially from 400 to 650C. This is because when molding a mixture of crystalline glass and a filler, a molding binder such as an organic resin is added, but this binder is efficiently removed, and at the same time, firing conditions with metallization that is fired at the same time as the insulating substrate. Necessary to achieve matching, the yield point is 40
If the temperature is lower than 0 ° C., the sintering of the crystalline glass starts at a low temperature.
This is because simultaneous firing with metallization at 0 to 800 ° C. cannot be performed, and densification of the molded body starts at a low temperature, so that the binder cannot be decomposed and volatilized, and a binder component remains to affect the properties. On the other hand, the yield point is 800
If the temperature is higher than ℃, sintering becomes difficult unless the amount of crystalline glass is increased, and the cost of the sintered body is increased because a large amount of expensive crystalline glass is required.

It is desirable that the amount of this filler component be appropriately adjusted according to the yield point of the crystalline glass. That is, when the yield point of the crystalline glass is as low as 400 ° C. to 650 ° C., the sinterability at low temperatures is increased, so that the content of the filler can be relatively large as 50 to 80% by volume. On the other hand, when the yield point of the crystalline glass is as high as 650 ° C. to 800 ° C., the sinterability is reduced, so that the content of the filler is 20 to
It is desirable to add a relatively small amount of 50% by volume.

The crystalline glass used in the present invention has a shrinkage initiation temperature of 700 ° C. or lower without a filler, and melts at 850 ° C. or higher, so that a metallized wiring layer or the like cannot be provided. But 2 fillers
By mixing in a proportion of 0 to 80% by volume, a liquid phase for crystal precipitation and liquid phase sintering of the filler component can be formed at the firing temperature. Further, since the shrinkage start temperature of the entire molded body can be raised, it is possible to match the simultaneous firing conditions with the metallized wiring layer depending on the type of metallization used by adjusting the content of the filler. Further, in order to reduce the raw material cost, it is preferable to reduce the content of expensive crystalline glass.

For example, as the metallized wiring layer, Cu,
When the metallization is made of one or more of Ag, Ni, Pd, and Au, firing of these metallizations is 600 to 1000.
Since it occurs at a temperature of 0 ° C., the yield point of the crystalline glass is preferably 400 ° C. to 650 ° C., and the content of the filler is preferably 50% to 80% by volume in order to perform the co-firing. Further, by reducing the amount of the expensive crystalline glass, the cost of the sintered body can be reduced.

The linear thermal expansion coefficient of the crystalline glass at 40 ° C. to 400 ° C. is 6 to 18 ppm / ° C., especially 7 to
It is also necessary to be 13 ppm / ° C. This is because when the linear thermal expansion coefficient deviates from the above range, a difference in thermal expansion with the filler occurs, which causes a decrease in strength of the sintered body. Further, if the linear thermal expansion coefficient of the filler is less than 6 ppm / ° C, it becomes difficult to set the linear thermal expansion coefficient of the sintered body to 8 to 18 ppm / ° C.

Examples of the crystalline glass satisfying the above characteristics are SiO ₂ —Li ₂ O—Al ₂ O ₃ and SiO ₂ —Li ₂ O—Al ₂ O ₃ —MgO—TiO ₂ SiO ₂ —Li ₂ O. _{-Al 2 O 3 -MgO-Na 2} O-F SiO 2 -Li 2 O-Al 2 O 3 -K 2 O-Na 2 O-ZnO, SiO 2 -Li 2 O-Al 2 O 3 -K 2 O _{-P 2 O 5 SiO 2 -Li 2} O-Al 2 O 3 -K 2 O-P 2 O 5 -ZnO-Na 2 O SiO 2 -Li 2 O-MgO, SiO 2 -Li 2 O-ZnO, etc. composition can be mentioned, of which according to the SiO ₂ is present invention, an essential component for forming a lithium silicate, SiO ₂ is in the glass the total amount, present in a proportion of 60 to 85 wt%, The total content of SiO ₂ and Li ₂ O is 65 to 95% by weight in the total amount of glass, and lithium silicate It is desirable for precipitating crystals. In this lithium silicate glass, B ₂ O ₃ is desirably 1% by weight or less.

The mixture of the crystalline glass and the filler is added to an organic resin binder of a suitable shape, and then formed into a sheet by a desired forming means such as a doctor blade, a rolling method or a die press. After molding, it is fired.

In firing, first, the binder component blended for molding is removed. The binder is removed in an air atmosphere at about 700 ° C., but when Cu is used as the wiring conductor, it contains water vapor.
This is performed in a nitrogen atmosphere at 0 to 700 ° C. At this time, it is preferable that the shrinkage start temperature of the molded body is about 700 to 850 ° C., and if the shrinkage start temperature is lower than this, it becomes difficult to remove the binder. It is necessary to control the yield point as described above.

The firing is performed in an oxidizing atmosphere at 850 ° C. to 1300 ° C., whereby the relative density is densified to 90% or more. If the baking temperature at this time is lower than 850 ° C., the metallization layer cannot be densified, and if it exceeds 1300 ° C., the metallization layer is melted by simultaneous baking with the metallization wiring layer. However, when Cu is used as the wiring conductor, 85
This is performed in a non-oxidizing atmosphere such as nitrogen at 0 to 1050 ° C.

In the glass-ceramic sinter thus produced, the crystalline phase produced from crystalline glass, the crystalline phase produced by the reaction of crystalline glass and the filler,
Alternatively, there is a crystal phase or the like generated by decomposition of the filler component, and a glass phase exists at the grain boundaries of these crystal phases.
As the crystal phase to be precipitated, in order to increase the linear thermal expansion coefficient of the entire sintered body, it is desirable that a crystal phase having a linear thermal expansion coefficient of at least 6 ppm / ° C at 40 to 400 ° C be precipitated.

Examples of such a crystal phase having a linear thermal expansion coefficient of 6 ppm / ° C. or higher include cristobalite (SiO ₂ ),
Quartz (SiO ₂ ), tridymite (SiO ₂ ), forsterite (2MgO · SiO ₂ ), spinel (M
gO ・ Al ₂ O ₃ ), wollastonite (CaO ・ Si
O ₂ ), Monticellanite (CaO ・ MgO ・ SiO
₂ ), nepheline (Na ₂ O ・ Al ₂ O ₃・ Si
O ₂ ), lithium silicate (Li ₂ O.SiO ₂ ),
Jiopusaido _{(CaO · MgO · 2SiO 2)} , Merubinaito _{(3CaO · MgO · 2SiO 2)} , Akerumaito _{(2CaO · MgO · 2SiO 2)} , magnesia (M
gO), alumina (Al ₂ O ₃ ), carnegieite (N
a ₂ O.Al ₂ O ₃ .2SiO ₂ ), enstatite (MgO.SiO ₂ ), magnesium borate (2MgO
・ B ₂ O ₃ ), celsian (BaO ・ Al ₂ O ₃・ 2S)
iO ₂ ), B ₂ O ₃ .2MgO.2SiO ₂ , garnite (ZnO.Al ₂ O ₃ ), petalite (LiAlSi)
_At least one selected from the group of ₄ O ₁₀ ). Among these, a crystal phase of 8 ppm / ° C. or more is particularly preferable. In addition, the linear thermal expansion coefficient of the final sintered body may exceed 18 ppm / ° C. due to the addition of the filler. In that case, it is necessary to mix with a filler having a small coefficient of linear thermal expansion to appropriately control the coefficient of linear thermal expansion.

Further, using the above sintered body as an insulating substrate, C
In order to manufacture a wiring board or a package in which a metallized wiring layer made of at least one of u, Ag, Ni, Pd, and Au is arranged, a crystallized glass and a filler as described above for forming an insulating substrate are manufactured. An appropriate organic binder, a plasticizer, and a solvent are added to and mixed with the raw material powder made of to prepare a slurry, and the slurry is prepared as a green sheet (raw sheet) by employing a doctor blade method or a calendar roll method. Then, as the metallized wiring layer 3 and the connection pad, a metal paste obtained by adding and mixing an organic binder, a plasticizer and a solvent to an appropriate metal powder is printed and applied to the green sheet in a predetermined pattern by a known screen printing method. In some cases, the green sheet is appropriately punched to form a through hole, and the hole is filled with a metallizing paste.
By stacking a plurality of these green sheets and simultaneously firing the green sheets and metallization, a package having a multilayer structure can be obtained.

The present invention will be described below in more concrete examples.

[0053]

【Example】

Example 1 As crystalline glass, 74% by weight of SiO ₂ −1
4% Li ₂ O-4% Al ₂ O ₃ -2% P ₂ O ₅ -2% K
₂ O-2% ZnO-2% Na ₂ O (Pb content 50 pp
m or less, yield point 480 ° C), and weight ratio of 78%
_{SiO 2 -10% Li 2 O-} 4% Al 2 O 3 -2% P 2
Two kinds of glass having O ₅ -2% K ₂ O-3% K ₂ O-1% Na ₂ O (Pb content of 50 ppm or less, yield point 480 ° C.) were prepared, and shown in Table 1 for this glass. As a filler component, forsterite (2MgO.Si
O ₂ , linear thermal expansion coefficient 10ppm / ° C, quartz (Si
O ₂ , linear thermal expansion coefficient 15 ppm / ° C., cristobalite (SiO ₂ , linear thermal expansion coefficient 20 ppm / ° C.), wollastonite (CaO · SiO ₂ , linear thermal expansion coefficient 9 ppm)
/ ° C), petalite (LiAlSi ₄ O ₁₀ , linear thermal expansion coefficient 8 ppm / ° C), MgO (linear thermal expansion coefficient 9 ppm /
℃), nepheline (Na ₂ O ・ Al ₂ O ₃・ SiO ₂ ,
Linear thermal expansion coefficient 9ppm / ℃) Mullite (3Al ₂ O ₃ ·
2SiO ₂ , linear thermal expansion coefficient of 4 ppm / ° C.), and alumina (Al ₂ O ₃ , linear thermal expansion coefficient of 7 ppm / ° C.) were weighed and mixed so as to have the composition shown in Table 1. After pulverizing this mixture, adding an organic binder and thoroughly mixing the mixture, a molded product having a shape of 3.5 × 3.5 × 15 mm is produced by a uniaxial pressing method, and the molded product is subjected to N ₂ at 700 ° C. +
After debindering in H ₂ O, 65 in a nitrogen atmosphere
A sintered body was produced by firing at 0 to 1300 ° C.

Next, the coefficient of linear thermal expansion at 40 to 400 ° C. was measured for the sintered body obtained as described above and shown in Table 1. Further, the sintered body was processed into a diameter of 60 mm and a thickness of 2 mm, and the relative dielectric constant and the dielectric loss were determined by the method of JISC2141. The measurement is performed using an LCR meter (YHP4284A) at 25 ° C under the conditions of 1 MHz and 1.0 Vrsm.
Was measured, and the relative dielectric constant at 25 ° C. was measured from the capacitance. Moreover, the presence or absence of residual carbon after the binder removal treatment was confirmed.

(Heat cycle test during mounting) Next, using each raw material composition in Table 1, toluene and isopropyl alcohol as a solvent, an acrylic resin as a binder, and DBP (dibutyl phthalate) as a plasticizer were used to prepare a doctor blade. A green sheet having a thickness of 500 μm was produced by the method.

A Cu metallization paste was applied to the surface of this green sheet by a screen printing method to apply a metallization wiring layer. Also, a through hole is formed at a predetermined position of the green sheet so that the inside of the through hole is finally exposed to the lower surface of the substrate, and Cu is also formed in the through hole.
Filled with metallization paste. Then, six green sheets to which the metallizing paste was applied were laminated and pressure-bonded while positioning the through holes.

After removing the binder from this laminate in N ₂ + H ₂ O at 700 ° C., the metallized wiring layer and the insulating substrate were simultaneously fired in a nitrogen atmosphere at each firing temperature to produce a wiring board for a package.

Next, a concave portion was formed on the lower surface of the wiring board at a position to be connected to the through hole, and a connection pad made of Cu metallization was prepared. Then, connection terminals made of solder (30 to 10% of tin-70 to 90% of lead) were attached to the connection pads as shown in FIG. The connection terminal is 1 cm ²
It was formed on the entire lower surface of the wiring board at a density of 30 terminals per contact.

On the other hand, a glass-epoxy substrate 40
A printed circuit board having a wiring conductor made of a copper foil formed on the surface of an insulator having a linear thermal expansion coefficient of 13 ppm / ° C. at −800 ° C. was prepared.

Then, the package wiring board is aligned so that the wiring conductors on the printed circuit board and the connection terminals of the package insulating board are connected, and this is placed in an N ₂ atmosphere at 260 ° C. for 3 minutes. After heat treatment, the package wiring board was mounted on the surface of the printed board. By this heat treatment, it was confirmed that the solder connection terminals of the package wiring board were melted and electrically connected to the wiring conductors of the printed circuit board.

Next, the test sample was mounted on the surface of the printed wiring board for packaging as described above, and the test sample was placed in a constant temperature bath controlled at temperatures of -40 ° C. and 125 ° C. for 15 minutes / Holding for 15 minutes was set as one cycle, and the cycle was repeated up to 1000 cycles. The electrical resistance between the wiring conductor of the printed circuit board and the wiring substrate for the package was measured for each cycle, and the number of cycles until the electrical resistance changed was shown in Table 1. Further, with respect to the Cu metallized layer obtained by co-firing, peeling, melting, and sintering failure of the metallized layer were evaluated.

[0062]

[Table 1]

As is clear from Table 1, in the sample No. 9 having a glass content of less than 20% by volume, a dense sintered body could not be obtained, and the sample No. 2 exceeding 80% by volume was not obtained. , 7, 15 and 16, the metallized layer was melted and Cu
And could not be fired at the same time.

On the other hand, the product of the present invention having a filler content of 20 to 80% by volume did not cause debye failure and the co-firing of Cu metallization was good. Further, in a package wiring board manufactured by using a glass ceramic having a linear thermal expansion coefficient of 8 to 18 ppm / ° C. as an insulating substrate, there is no change in electrical resistance between the wiring conductor of the printed circuit board and the package wiring board even after 1000 cycles of temperature increase / decrease. It was not seen at all, and extremely stable and good electrical connection could be maintained.

Further, as a result of identifying the crystal phase by X-ray diffraction measurement, the crystal phases of lithium silicic acid and the filler component were detected as the crystal phases in all the sintered bodies of the present invention.

Example 2 As crystallizable glass, as shown in Table 2, the ratio of glass: filler was 30:70 in weight ratio, using forsterite as a filler, with respect to glasses having different amounts of Li ₂ O. Were mixed in the same manner as in Example 1, molded in the same manner as in Example 1, debindered, and fired at the temperatures shown in Table 2.
Then, in the same manner as in Example 1, with respect to the sintered body obtained as described above, the linear thermal expansion coefficient at 40 to 400 ° C., the relative dielectric constant, the dielectric loss, and the presence or absence of residual carbon after the debinding process were performed. It was confirmed.

A wiring board having Cu as a metallized wiring layer was prepared in the same manner as in Example 1 using the compositions shown in Table 2.
This was mounted on a glass-epoxy substrate, a thermal cycle test at the time of mounting was performed, and a wiring layer of Cu metallization by simultaneous firing was observed. The results are shown in Table 3.

[0068]

[Table 2]

[0069]

[Table 3]

As is clear from the results of Tables 2 and 3, the sample No. 32 having a yield point lower than 400 ° C. could not be co-fired with Cu. In the sample No. 33 having a yield point of more than 800 ° C., it was not possible to sinter unless the firing temperature was raised, and therefore Cu metallization could not be performed.
In addition, a sample No. 2 containing no Li ₂ O in the crystallized glass
In No. 6, the coefficient of linear thermal expansion was lower than 6 ppm / ° C., and the occurrence of cracks which was considered to be due to the difference in thermal expansion with the filler was recognized. Further, in the sample No. 31 having a Li ₂ O content of more than 30% by weight, the dielectric loss was larger than 100 × 10 ^-4 .

On the other hand, if the Li ₂ O content is 5 to 30
In Sample Nos. 27 to 30 using glass having a yield point of 400 ° C. to 800 ° C., the binder can be almost completely removed to produce a dense sintered body. I was able to. Further, co-firing with the Cu metallized layer was also possible and showed strong adhesive strength.

As a result of the identification of the crystal phase by X-ray diffraction measurement, lithium silicic acid and the forsterite crystal phase as the filler component were detected in all the samples except the sample No. 26 in which Li ₂ O was not present. Was done.

[0073]

As described above in detail, according to the wiring board and the package for accommodating semiconductor elements of the present invention, when the wiring board and the package for mounting the semiconductor element are mounted on an external electric circuit board such as a printed circuit board having a large coefficient of linear thermal expansion, the wires of the both boards are accommodated. It is possible to suppress the stress generation due to the difference in the coefficient of thermal expansion, and to electrically connect the package and the external electric circuit accurately and firmly for a long period of time. Moreover, it is possible to realize a highly reliable package mounting structure that can sufficiently cope with the increase in the number of pins due to the increase in size of semiconductor circuit elements.

Furthermore, the cost of raw materials can be reduced by combining high-cost crystalline glass and low-cost filler,
Moreover, since it is possible to perform co-firing with metallization and remove the binder efficiently, it is possible to provide a high-quality and inexpensive wiring board and semiconductor element housing package.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view for explaining a mounting structure of a BGA type semiconductor element housing package of the present invention.

FIG. 2 is an enlarged sectional view of a main part of FIG.

FIG. 3 is an enlarged sectional view of a main part of another embodiment of the connection terminal.

FIG. 4 is a cross-sectional view for explaining a mounting structure of a leadless chip carrier type package of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating substrate 1b ... Recess 2 ... Lid 3 ... Metallized wiring layer 3a ... Connection pad 4 ... Connection terminal 4a ... Projection 5 ... Semiconductor element 6 ... Container 8 ... Wiring conductor 9 ... Insulator A ... BGA type package B ... External electric circuit board C ... LCC type package

Front page continued (72) Inventor Takeshi Kubota 1-1 Yamashita-cho, Kokubun-shi, Kagoshima Kyocera Stock Company Kagoshima Kokubun Plant (72) Inventor Ren Kunimatsu 1-1, Yamashita-cho, Kokubun-shi, Kagoshima Kyocera Corporation Inside the Kagoshima Kokubu Factory

Claims (3)

[Claims] 1. A wiring board in which a metallized wiring layer is provided on the surface or inside of an insulating substrate, wherein the insulating substrate contains 5 to 30% by weight of Li ₂ O and has a yield point of 400.
20 ~ 80% by volume of lithium silicate glass at ℃ ~ 800 ℃
And the linear thermal expansion coefficient at 40 ° C to 400 ° C is 6 ppm
40 ° C. to 40 ° C. obtained by firing a molded body containing a filler containing a metal oxide of not less than / ° C. at a ratio of 80 to 20% by volume.
A wiring board comprising a sintered body having a linear thermal expansion coefficient at 0 ° C of 8 to 18 ppm / ° C. 2. A semiconductor element is housed in a container consisting of an insulating substrate having connection terminals attached thereto and a lid, and the connection terminals and electrodes of the semiconductor element are arranged on the surface or inside of the insulating substrate. In a package for housing a semiconductor element, which is electrically connected by the provided metallized wiring layer,
The insulating substrate contains lithium silicate glass having a Li ₂ O content of 5 to 30% by weight and a yield point of 400 ° C. to 800 ° C.
8 to 80% by volume and a filler containing a metal oxide having a linear thermal expansion coefficient of 6 ppm / ° C. or more at 40 ° C. to 400 ° C.
The linear thermal expansion coefficient at 40 ° C. to 400 ° C. obtained by firing a molded body containing 0 to 20% by volume is 8 to 18 pp.
A package for storing a semiconductor element, which is made of a sintered body of m / ° C. 3. The connection terminal of the package for accommodating a semiconductor element according to claim 2, wherein the wiring conductor is soldered to the wiring conductor on an external electric circuit board having a wiring conductor adhered to the surface of an insulator containing at least an organic resin. A mounting structure of a package for accommodating a semiconductor element, which is characterized by being attached and bonded.