JP2510585Y2 - Package for storing semiconductor devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in a semiconductor device housing package for housing a semiconductor device, particularly a semiconductor integrated circuit device.

(Prior Art and Problems Thereof) In recent years, as the performance and speed of information processing apparatuses have increased, the density and integration of semiconductor elements constituting the information processing apparatuses have rapidly increased. Therefore, the amount of heat generated per unit area and unit volume of the semiconductor element increases, and a problem is how to efficiently remove the heat in order to operate the semiconductor element normally and stably.

Conventionally, as a method for removing heat generated by a semiconductor element, as shown in FIG. 2, a mounting portion 11a is placed on a metal base 11 having a mounting portion 11a on which a semiconductor element 13 is mounted in a central portion of an upper surface. A semiconductor element housing package having a structure in which the insulating frame 12 is brazed and attached so as to surround the semiconductor element 13 is mounted on the semiconductor element mounting portion 11a of the metal base 11 and the semiconductor element 13 is The heat generated is absorbed by the metal substrate 11 and the absorbed heat is released to the atmosphere.

In the package for housing the semiconductor element, the metal base body 11 has a thermal expansion coefficient of the insulating frame body 12 so that a large thermal stress is not generated between the metal base body 11 and the insulating frame body 12 which is brazed and attached to the upper surface.
Is formed of a metal similar to that of, for example, a copper-tungsten alloy (Cu-W alloy), and the insulating frame 12 has a high melting point of molybdenum (Mo), tungsten (W), manganese (Mn), etc. on its lower surface. A metallized metal layer 14 made of a metal is deposited and formed, and the metallized metal layer 14 is formed on a metal substrate.
The insulating frame body 12 is brazed and attached to the metal base 11 by brazing to the metal base 11 via a brazing material 15 such as silver braze (Ag—Cu alloy).

However, in this conventional semiconductor element storage package, since the semiconductor element 13 is directly attached to the metal base 11 and the lower surface of the metal base 11 is largely exposed, the semiconductor element storage package is When mounted on an external circuit board, if other electronic components or wiring conductors on the circuit board come into contact with the metal base 11, unnecessary electricity will flow to the semiconductor element 13 housed inside via the metal base 11. As a result, there is a defect that the semiconductor element 13 may malfunction or its characteristics may deteriorate.

Therefore, in order to solve the above-mentioned drawbacks, the present applicant first applied aluminum oxide (alumina: Al ₂ O ₃ ) to the outer surface of the metal substrate.
We proposed a package for accommodating semiconductor devices in which an insulating coating layer consisting of is deposited by sputtering etc.
(See the official gazette).

However, in this semiconductor device housing package, the thermal expansion coefficient of aluminum oxide that constitutes the insulating coating layer is about 7.
0 × 10 ^-6 / ° C, which is different from the thermal expansion coefficient (6.0 × 10 ^-6 / ° C) of copper-tungsten that composes the metal substrate, and the heat generated by conventional semiconductor devices is about 3 W However, the current value is about 10 W, and the calorific value is more than three times as large, which causes the following defects.

That is, since there is a difference in thermal expansion coefficient between the insulating coating layer and the metal substrate, when heat generated by the semiconductor element is applied to both, a thermal stress is generated between the two and the insulating coating layer is formed by the thermal stress. When peeled off from the metal base, as a result of which the metal base is exposed and other electronic components or wiring conductors on the circuit board come into contact with the metal base, unnecessary electricity is generated in the semiconductor element housed inside through the metal base. Flow, which may cause the semiconductor element to malfunction or cause deterioration in characteristics. Further, when the insulating coating layer is peeled off from the metal substrate, the semiconductor element attached on the insulating coating layer is also simultaneously welded to the metal substrate. As a result, the heat generated by the semiconductor element cannot be satisfactorily conducted and absorbed by the metal substrate, and the electrodes of the semiconductor element can be satisfactorily electrically connected to the external circuit board. Had drawbacks such as resulting in loss of function as a semiconductor device can no longer be connected.

(Object of the Invention) The present invention has been devised in view of the above-mentioned drawbacks, and an object thereof is to firmly adhere an insulating coating layer to a metal substrate to prevent unnecessary electricity from flowing to a semiconductor element housed inside. It is an object of the present invention to provide a package for accommodating a semiconductor element, which can operate the semiconductor element normally and stably over a long period of time without any element.

(Means for Solving the Problems) The present invention is made of a copper-tungsten alloy, and surrounds the mounting portion on a metal substrate having a mounting portion on which a semiconductor element is mounted in the center of the upper surface. In a package for accommodating a semiconductor element formed by attaching an insulating frame, at least the surface of the semiconductor element mounting portion of the metal substrate is provided with 30.0 to 70.0% by weight of amorphous glass and 30.0 to 70.0% by weight of aluminum oxide powder, and It is characterized in that an insulating coating layer containing at least one of tight powder and spinel powder is applied.

(Example) Next, this invention is demonstrated in detail based on an accompanying drawing.

FIG. 1 shows an embodiment of a package for housing a semiconductor device of the present invention, in which 1 is a metal base and 2 is an insulating frame.

The metal base 1 is provided with a convex mounting portion 1a for mounting the semiconductor element 3 on the center of the upper surface thereof.
The semiconductor element 3 is attached to the upper side with an adhesive.

The metal base 1 directly conducts and absorbs the heat generated by the semiconductor element 3 and releases the absorbed heat into the atmosphere, so that a large thermal stress is not generated between the metal base 1 and the insulating frame 2 described later. It is made of a material having a coefficient of expansion similar to that of the insulating frame 2 and good thermal conductivity, specifically, a copper-tungsten alloy (Cu-W alloy).

The metal base 1 made of the copper-tungsten alloy
Is, for example, tungsten powder (about 10 μm) 1000 Kg / c
Pressure molding with a pressure of m ² and this in a reducing atmosphere,
To obtain a porous tungsten sintered body by firing at a temperature of about 2300 ° C., and then to impregnate the porous portion of the tungsten sintered body with a capillary phenomenon by using copper heated and melted at a temperature of 1100 ° C. Formed by.

The metal base 1 has an insulating coating layer 4 deposited on the surface of the semiconductor element mounting portion 1a.

The insulating coating layer 4 serves to electrically insulate and separate the metal base 1 from the semiconductor element 3 mounted on the semiconductor element mounting portion 1a of the metal base 1, and the metal base 1 is provided on the circuit board. Even if other electronic components or wiring conductors come into contact with each other and unnecessary electric power flows to the semiconductor element 3 through the metal substrate 1, the electric current flow is completely blocked by the insulating coating layer 4 and is unnecessary for the semiconductor element 3. No electricity flows.

The insulating coating layer 4 comprises 30.0 to 70.0% by weight of amorphous glass and 30.0 to 70.0% by weight of aluminum oxide powder,
It is made by containing at least one of steatite powder and spinel powder, and its thermal expansion coefficient is 5.7 to 6.5 × 10 ^-6 / ° C.
Then, it is approximated to the thermal expansion coefficient of copper-tungsten forming the metal substrate 1. Therefore, even if the heat generated by the semiconductor element 3 is applied to both the insulating coating layer 4 and the metal substrate 1, the thermal expansion coefficients of the two are similar to each other, so that a large thermal stress does not occur between the two and the thermal stress is not generated. Insulation coating layer 4
Does not separate from the metal substrate 1.

The insulating coating layer 4 is composed of amorphous glass as silicon oxide (SiO ₂ ) 64.0% by weight, boron oxide (B ₂ O ₃ ) 19.0% by weight,
A glass comprising 8.0% by weight of aluminum oxide (Al ₂ O ₃ ), 3.0% by weight of sodium oxide, 3.0% by weight of potassium oxide (K ₂ O), 2.0% by weight of (Na ₂ O), etc. is preferably used, and the amorphous glass powder is At least one of aluminum oxide powder, steatite powder, and spinel powder, and an appropriate organic solvent and solvent are added and mixed to form a slurry, which is printed and applied on the semiconductor element mounting portion 1a of the metal substrate 1 and at the same time. The semiconductor element mounting portion of the metal substrate 1 is baked by baking at a temperature of 1000 ° C.
1a is applied to the surface.

When the amount of aluminum oxide powder, steatite powder, and spinel powder contained in the amorphous glass is less than 30.0% by weight, or exceeds 70.0% by weight, the thermal expansion coefficient of the insulating coating layer 4 becomes insulating. Since the thermal expansion coefficient of the coating layer 4 is not satisfied, the insulating coating layer 4 cannot be firmly adhered to the metal substrate 1. Therefore, the amounts of aluminum oxide powder, steatite powder, and spinel powder contained in the amorphous glass are limited to the range of 30.0 to 70.0% by weight.

If 1.0 to 10.0 parts by weight of at least one of niobium oxide and tantalum oxide is added to the inside of the insulating coating layer 4, the wettability of the insulating coating layer 4 with respect to the metal substrate 1 is greatly improved, and the insulating coating layer 4 Can be firmly adhered to the metal substrate 1. Therefore, the insulating coating layer 4 contains at least one of niobium oxide and tantalum oxide in the range of 1.0 to 10.0.
It is desirable to add parts by weight.

Further, if the thickness of the insulating coating layer 4 is less than 5.0 μm, the electrical insulation between the metal substrate 1 and the semiconductor element 3 is insufficient, and unnecessary electricity easily flows to the semiconductor element 3. When the thickness exceeds 250.0 μm, the heat generated by the semiconductor element 3 tends not to be well conducted and absorbed by the metal substrate 1, so that the thickness of the insulating coating layer 4 is 5.0 to 250.0 μm.
It is preferable to set it in the range of m.

The metal base 1 has an insulating frame body 2 attached to the outer peripheral edge of the upper surface of the metal base body 1 so as to surround the convex mounting portion 1a provided on the upper surface of the metal base body 1. A space for accommodating the semiconductor element 3 is formed with 2.

The insulating frame 2 is made of an electrically insulating material such as alumina ceramics. For example, a powder of alumina ceramics is mixed with an appropriate organic solvent or solvent to form a slurry, and the slurry is formed by a doctor blade method. (Ceramic green sheet) is formed, and thereafter, the green sheet is appropriately punched, and a plurality of sheets are laminated and fired at a high temperature.

On the lower surface of the insulating frame 2, a metallized metal layer 5 made of a high melting point metal powder such as tungsten or molybdenum is deposited. The metallized metal layer 5 and the metal base 1 are coated with a brazing material 6 such as silver solder. It is attached to the metal substrate 1 by brazing via.

A conductive layer 7 made of a high melting point metal powder such as molybdenum or tungsten is provided inside the insulating frame 2. The conductive layer 7 functions to connect the electrode of the semiconductor element 3 to the external lead pin 8. , An external lead pin 8 at one end
However, the bonding wire 9 connected to the electrode of the semiconductor element 3 is attached to the other end.

The external lead pins 8 attached to the conductive layer 7 provided on the insulating frame 2 serve to connect the electrodes of the semiconductor element 3 housed inside to an external circuit, and are made of Kovar (Fe-Ni-Co alloy). A metal such as 42Alloy (Fe-Ni alloy) processed into a rod shape is used.

It should be noted that nickel (N
i), if a metal having good conductivity and excellent corrosion resistance made of gold (Au) is layered by a plating method, the electrical connection between the external lead pin 8 and the external circuit becomes good, and the external lead pin 8 The oxidative corrosion of is effectively prevented. Therefore,
On the outer surface of the external lead pin 8, nickel (Ni), gold (A
u), which is a metal with good conductivity and excellent corrosion resistance
It is preferable to layer them to a thickness of 10 to 10 μm.

A lid 10 is attached to the upper surface of the insulating frame 2 via a sealing material such as glass or resin, whereby the inside of the semiconductor element housing package is completely hermetically sealed.

Thus, the semiconductor element 3 is mounted on the convex mounting portion 1a of the metal substrate 1 to which the insulating frame 2 is mounted, and each electrode of the semiconductor element 3 is connected to the conductive layer 7 through the bonding wire 9. By attaching the lid body 10 to the upper surface of the insulating frame body 2 with a sealing material interposed therebetween, a semiconductor device as a final product is obtained.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. For example, the insulating coating layer 4 may be used as the semiconductor element mounting portion of the metal substrate 1. Not limited to the surface 1a, it may be adhered to the entire outer surface of the metal substrate 1. In this case, the insulating coating layer 4
In order to prevent unnecessary flow of electricity to the semiconductor element 3 and effectively prevent oxidative corrosion of the metal substrate 1, it is preferable that the insulating coating layer 4 be deposited on the entire outer surface of the metal substrate 1.

(Effect of the Invention) According to the package for accommodating a semiconductor element of the present invention, at least the surface of the semiconductor element mounting portion of the metal base having a thickness of 30.0 to 30.0.
Since a 70.0 wt% amorphous glass is coated with an insulating coating layer containing 30.0 to 70.0 wt% of at least one of aluminum oxide powder, steatite powder, and spinel powder, a package for housing a semiconductor device is obtained. When mounted on a circuit board, even if other electronic components or wiring conductors on the circuit board contact the metal base, the metal base and the semiconductor element mounted on the upper surface of the metal base are electrically connected by the insulating coating layer. Since they are electrically isolated from each other, no unnecessary electricity flows through the semiconductor element, and the semiconductor element accommodated inside can be normally and stably operated for a long period of time.

Further, since the insulating coating layer of the present invention has a coefficient of thermal expansion similar to that of copper-tungsten which constitutes the metal substrate, even if heat generated by the semiconductor element is applied to both the insulating coating layer and the metal substrate, the heat is generated between the two layers. No thermal stress is generated, and the insulating coating layer does not peel off from the metal substrate. Therefore, also by this, the semiconductor element housed inside can be normally and stably operated for a long period of time.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a semiconductor device housing package according to the present invention, and FIG. 2 is a sectional view of a conventional semiconductor device housing package. 1 ... Metal substrate, 1a ... Semiconductor element mounting portion 2 ... Insulating frame, 4 ... Insulating coating layer

Claims (1)

(57) [Scope of utility model registration request] 1. An insulating frame body is mounted on a metal base made of a copper-tungsten alloy and having a mounting portion on which a semiconductor element is mounted in the center of the upper surface so as to surround the mounting portion. In a package for storing a semiconductor element, which is composed of at least 30.0 to 70.0% by weight of amorphous glass on the surface of at least the semiconductor element mounting portion of the metal base, 30.0 to 70.0% by weight of aluminum oxide powder, steatite powder, and spinel powder. A package for accommodating a semiconductor element, characterized in that an insulating coating layer containing one kind is deposited.