JPH11204691A - High frequency i/o terminal and package for high frequency semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a more reliable high frequency I/O terminal in which loss of high frequency signal is reduced by improving moisture resistance characteristics. SOLUTION: A dielectric wall member 27 is bonded to the upper surface of a dielectric substrate 26 through a part of a signal line 25b comprising a main conductor layer 28 of high melting point metal, a first plating layer 29 principally comprising nickel applied to the exposed surface thereof, a moisture resistant insulating coating material 31 covering the main conductor layer 28 and the first plating layer 29 within a range of 0.3-2 mm from the surface of the dielectric wall member 27, and a second plating layer 30 which principally comprises gold applied to the exposed surface of the first plating layer 29. According to the structure, moisture resistance characteristics can be enhanced by preventing the open circuit of the signal line due to the dew formation with the moisture resistant insulating coating material 31, while ensuring good high frequency transmission characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in a high frequency input / output unit of a high frequency semiconductor device package for accommodating a high frequency semiconductor element or a high frequency electronic circuit used for a microwave circuit or a millimeter wave circuit. The present invention relates to a high-frequency input / output terminal and a package for a high-frequency semiconductor device using the high-frequency input / output terminal, and more particularly to an improvement in their reliability.

[0002]

2. Description of the Related Art A high-frequency semiconductor element or a high-frequency electronic circuit using a high-frequency signal such as a microwave band or a millimeter-wave band is housed in a hermetically sealed state, and a high-frequency signal of a high-frequency semiconductor device package constituting a high-frequency semiconductor device is formed. In the input / output terminal section, a structure in which a signal line such as a microstrip line or a coplanar line formed on a dielectric substrate as a high-frequency transmission line and an inner layer signal line of a hermetic seal portion are generally used.

[0003] The input / output terminals are formed as signal input / output portions of a high-frequency semiconductor device package, and are also prepared as high-frequency input / output terminals and incorporated into the package.

As a package for a high-frequency semiconductor device having such an input / output terminal, a metal substrate and a frame-shaped metal wall member forming a container wall are cut out to provide a mounting portion for the high-frequency input / output terminal. A metal wall type structure in which a high frequency input / output terminal is fitted to the mounting portion or a frame-shaped dielectric wall member forming a dielectric substrate and a container wall is cut out to form a high frequency input / output terminal. A so-called ceramic wall type configuration in which a mounting portion is formed and high frequency input / output terminals are fitted to the mounting portion, or a high frequency input / output terminal is similarly fitted to a dielectric substrate and a frame-shaped metal wall member. And a structure in which the high-frequency input / output terminal having the above-described structure is formed on a dielectric substrate and a frame-shaped dielectric wall member.

For example, in the case of a package for a high-frequency semiconductor device having a metal wall type structure, a structure as shown in FIG.

In FIG. 3, reference numeral 1 denotes a substrate made of a metal plate such as copper, and reference numeral 2 denotes a frame-shaped wall member joined to the upper surface of the substrate 1 and made of metal such as copper or ceramic whose inner and outer surfaces are metallized. The substrate 1 is a plate-shaped member that also serves as a heat sink and a ground surface, and has a mounting portion on which a high-frequency semiconductor element or a high-frequency electronic circuit is mounted, and a wall member 2 surrounding the mounting portion. A high-frequency semiconductor element or a high-frequency electronic circuit, a matching circuit board, and the like (not shown) are mounted inside the cavity 3 formed by the substrate 1 and the substrate 3. Thereafter, a lid (not shown) made of metal or the like is attached to the upper surface of the wall member 2 by soldering, welding, or the like to form a high-frequency semiconductor device. It protects against disturbance.

In order to connect the inside and the outside of the cavity 3, a part of the wall member 2 is cut out and two kinds of feedthroughs are fitted and fixed by brazing or the like. One feedthrough 4 is for supplying power from an external electric circuit board or the like or supplying a low frequency such as a control signal, and the other feedthrough is a high frequency input / output terminal 5 for transmitting a high frequency signal. belongs to. Each of them includes a hermetic seal portion 4a, 5a composed of a dielectric substrate and a dielectric wall member, and a signal line 4b formed on the dielectric substrate so as to penetrate therethrough.
5b, and the signal lines 4b and 5b are made of metal and are insulated in a direct current manner from the substrate 1 and the wall member 2 serving as grounds. Also, in order not to be destroyed by a hot process such as brazing or mechanical stress,
Alumina ceramics is usually used as the dielectric.

It is the high-frequency input / output terminal 5 that determines the high-frequency performance of such a high-frequency semiconductor device package. The signal line 5b is usually provided on the surface of the signal line 5b inside and outside the cavity 3. A microstrip line which is exposed to the atmosphere, can be easily connected to other circuits by wire bonding or the like, and has good high frequency characteristics is used. However, in the hermetic seal portion 5a which penetrates the wall member 2, a microstrip line cannot be used. If the structure of the signal line 5b in this portion is significantly far from the microstrip line, a high-frequency signal is generated in that portion. Therefore, a strip line having a structure in which the signal line 5b penetrates a junction between the dielectric substrate and the dielectric wall member is used as the signal line 5b in the hermetic seal portion 5a because the reflection occurs and the high-frequency characteristics are significantly deteriorated. Normal.

In such a high frequency input / output terminal 5, when the dielectric is made of alumina ceramics, the signal line 5b uses a main conductor layer made of a metallized conductor layer of a refractory metal such as tungsten or molybdenum. In the portion of the microstrip line, nickel-plated and gold-plated metallized conductor layers of a high-melting-point metal are applied, and in the portion of the stripline, the metallized conductor layer of the high-melting-point metal is used as a sintered material.

[0010]

However, in the above-mentioned conventional high frequency input / output terminal 5, the leading end of the portion where the signal line 5b is exposed near the wall of the hermetic seal portion 5a composed of the dielectric substrate and the dielectric wall member. In the body layer, there is a problem that a small portion of nickel plating and gold plating is not sufficiently applied, so that when exposed to an environment such as high temperature and high humidity, the plating is not sufficient. There is a problem that the main conductor layer made of the high melting point metal is corroded preferentially in the part where the signal line 5b is not formed, and as a result, the signal line 5b is disconnected.

As described above, in the conventional high-frequency input / output terminal 5, the main conductor layer of the portion of the signal line 5b where the plating is not sufficiently applied is preferentially corroded in a high-temperature and high-temperature atmosphere, so that the signal line 5b is damaged. The reason for the disconnection will be described with reference to an enlarged sectional view of a main part of the high frequency input / output terminal 5 shown in FIG.

In FIG. 4, reference numeral 6 denotes a dielectric substrate, and reference numeral 7 denotes a dielectric wall member. A hermetic seal portion 5a is formed by joining these members. Reference numeral 8 denotes a main conductor layer made of a refractory metal such as tungsten or molybdenum formed on the upper surface of the dielectric substrate 6, reference numeral 9 denotes a nickel plating layer applied to the exposed surface of the microstrip line portion of the main conductor layer 8, reference numeral 10 Is a gold plating layer adhered to the surface of the nickel plating layer 9, and these constitute a signal line 5b. A denotes a portion of the hermetic seal portion 5a near the wall of the dielectric wall member 7 to which nickel plating and gold plating have not been sufficiently applied, and 11 denotes condensation adhering to the portion A.

In such a high frequency input / output terminal 5, the gold of the gold plating layer 10 and the tungsten or molybdenum of the main conductor layer 8 come into direct contact with each other at the portion indicated by A in FIG. When dew condensation 11 occurs, the dew condensation 11 becomes an electrolyte and forms a local battery. As a result, molybdenum and tungsten are ionized due to a difference in ionization tendency between gold and tungsten or molybdenum. A phenomenon of preferential corrosion will occur.

That is, of the four metal elements gold, nickel, tungsten, and molybdenum constituting the signal line 5b of the high frequency input / output terminal 5, nickel, tungsten, and molybdenum are used.
Since molybdenum has a high ionization tendency and gold has a low ionization tendency, when a battery is filled with an electrolyte between two of these four metals as electrodes, gold becomes the anode and nickel, tungsten and molybdenum become the cathode. In some cases, the reaction proceeds greatly, and these three metal elements having a high ionization tendency are eluted as ions in the electrolyte. However, nickel is not easily eluted because its surface is easily passivated. Therefore, gold (gold plated layer 10) and tungsten / molybdenum (main conductor layer 8) are in direct contact with each other, and an electrolyte (condensation 11) exists between them, as indicated by A in FIG. In this case, it is considered that gold serves as an anode and tungsten / molybdenum serves as a cathode, and tungsten / molybdenum is ionized and eluted, causing corrosion of the main conductor layer 8 and disconnection of the signal line 5b.

In order to solve such a problem, for example, as described below, the main conductor layer 8 is plated sufficiently to the portion near the wall of the hermetic seal portion 5a (dielectric wall member 7). The surface of the main conductor layer 8 made of a refractory metal such as tungsten or molybdenum is always covered with a nickel plating layer 9. The structure of the signal line 5b is changed so that even if the high melting point metal forming the main conductor layer 8 is preferentially ionized, the structure is not easily broken. The structure is such that the gold plating layer 10 and the main conductor layer 8 are not in direct contact with each other, so that a continuous electrolyte layer is unlikely to be formed between gold and the refractory metal even when the condensation 11 occurs. The exposed portion of the main conductor layer 8 is completely covered with the plating layer up to the wall so that even if dew condensation 11 occurs, the moisture does not contact the surface of the main conductor layer 8. Countermeasure plans such as this can be considered. However, in the high frequency input / output terminal 5, it goes without saying that the structure of the signal line 5b must be a structure through which high frequency signals can easily pass.

However, among the above-mentioned countermeasures, it is not necessary to change the structure of the signal line 5b, and it can be said that it is an ideal countermeasure. It is difficult to ensure completeness because bubbles easily remain in the solution or the plating solution hardly flows around the portion.

For example, an inner layer line conductor is formed inside the dielectric substrate 6 at a portion corresponding to the hermetic seal portion 5a, and the inner layer line conductor and the signal on the dielectric substrate 6 are provided before and after the hermetic seal portion 5a. There is a measure to connect the line 5b to the line 5b by a via conductor or the like so that the signal line has a structure bypassing the hermetic seal portion 5a. In this case, a high-frequency signal is easily reflected at the via conductor and transmission loss is reduced. Because it tends to be large,
It is difficult to provide high frequency input / output terminals having good high frequency characteristics.

Then, or is considered to be a practical countermeasure, and as a result of intensive research conducted by the present inventors on these, the high-frequency input / output terminal and the high-frequency semiconductor device package of the present invention have been completed. It is.

An object of the present invention is to provide a high-frequency input / output terminal with improved reliability and high loss of high-frequency signals with improved moisture resistance.

It is another object of the present invention to use a high-frequency input / output terminal with improved reliability and high loss of high-frequency signal, or to provide such a high-frequency input / output terminal. An object of the present invention is to provide a high-frequency semiconductor device package.

[0021]

The high frequency input / output terminal of the present invention has a ground conductor layer on the lower surface and a part of the signal line on the upper surface of a dielectric substrate having a signal line formed on the upper surface. In a high-frequency input / output terminal in which a dielectric wall member is joined to sandwich the signal line, the signal line mainly includes a main conductor layer made of a high melting point metal and nickel applied to an exposed surface of the main conductor layer. A first plating layer, a moisture-resistant insulating coating material covering the main conductor layer and the first plating layer within a range of 0.3 mm to 2 mm from the wall surface of the dielectric wall member, and exposing the first plating layer. And a second plating layer composed mainly of gold and adhered to the surface.

Further, in the high frequency input / output terminal according to the present invention, the moisture-resistant insulating coating material has a dielectric constant of 5 or less, a thermal expansion coefficient in a range of 7 to 10 ppm / ° C., and a softening temperature of It is characterized by being made of glass having a temperature of 1200 ° C. or less.

Further, a first high-frequency semiconductor device package of the present invention has a substrate having a mounting portion for mounting a high-frequency semiconductor element or a high-frequency electronic circuit on an upper surface, and a portion surrounding the mounting portion on the substrate. A frame-shaped wall member joined to the input / output terminal, an input / output terminal mounting portion formed by cutting out the wall member and having a conductive bottom surface, and a high-frequency And an input / output terminal for use.

Furthermore, a second high-frequency semiconductor device package of the present invention has a dielectric substrate having a grounding conductor on a lower surface and a mounting portion for mounting a high-frequency semiconductor element or a high-frequency electronic circuit on an upper surface; A signal line formed on the upper surface of the dielectric substrate from the vicinity of the mounting portion to the vicinity of the outer periphery of the dielectric substrate is joined to the dielectric substrate so as to surround the mounting portion and sandwich a part of the signal line. A frame-shaped dielectric wall member, wherein the signal line comprises a main conductor layer made of a high melting point metal, and a first plating layer containing nickel as a main component and applied to an exposed surface of the main conductor layer. A moisture-resistant insulating coating material that covers the main conductor layer and the first plating layer within a range of 0.3 mm or more and 2 mm or less from the wall surface of the dielectric wall member, and is attached to an exposed surface of the first plating layer. No. whose main component is gold It is characterized by comprising two plating layers.

Further, in the package for a high frequency semiconductor device according to the second aspect of the present invention, in the above structure, the moisture-resistant insulating coating material has a dielectric constant of 5 or less and a thermal expansion coefficient of 7 to 10 p.
It is characterized by being made of glass having a softening temperature of 1200 ° C. or lower within a range of pm / ° C.

According to the high frequency input / output terminal and the high frequency semiconductor device package of the present invention, the first plating layer mainly composed of nickel is formed on the exposed surface of the main conductor layer of the signal line near the wall of the dielectric wall member. The main conductor layer and the first plating layer are separated from the wall surface of the dielectric wall member by 0.3 mm or more.
mm or less, and a second plating layer containing gold as a main component is applied to the exposed surface of the first plating layer. By covering the part of the layer where the nickel plating has not been sufficiently applied with a moisture-resistant insulating covering material, direct contact between the main conductor layer composed of the high melting point metal and the gold plating layer and contact through the electrolyte such as condensation can be prevented. It can be avoided, and even if condensation occurs, the signal line will not corrode or break,
Moisture resistance can be significantly improved as compared with the conventional structure. Further, the signal line itself is a signal line having a small reflection like a conventional high-frequency semiconductor device package, and therefore has a small insertion loss. As a result, the humidity resistance is good, the reliability is high, and the loss of the high-frequency signal is small.

According to the high frequency input / output terminal and the high frequency semiconductor device package of the present invention, the moisture-resistant insulating coating material has a dielectric constant of 5 or less and a thermal expansion coefficient of 7 to 10%.
In the range of ppm / ° C, when a glass having a softening temperature of 1200 ° C or lower is used, the glass has excellent moisture resistance and completely prevents the slightly exposed main conductor layer from dew condensation and the like, Since the thermal expansion coefficient is close to that of ceramics such as alumina ceramics, which have excellent properties as a dielectric substrate, they have high reliability without cracking or peeling even if a thermal cycle load is applied. Will be excellent.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a partially broken perspective view similar to FIG. 3 showing an example of an embodiment of a high frequency input / output terminal and a first high frequency semiconductor device package of the present invention. Also,
FIG. 2 is an enlarged sectional view of a main part, similar to FIG. 4, showing the structure of the high-frequency input / output terminal of FIG.

In these figures, 21 is a substrate made of a metal plate such as copper, and 22 is a frame-shaped wall member joined to the upper surface of the substrate 21 and made of metal such as copper or ceramic whose inner and outer surfaces are metallized. . The substrate 21 is a plate-shaped member that also serves as a heat sink and a ground surface. The substrate 21 has a mounting portion on which a high-frequency semiconductor element or a high-frequency electronic circuit is mounted, and a wall member 22 surrounding the mounting portion. And substrate 21
A high-frequency semiconductor element or high-frequency electronic circuit, a matching circuit board, and the like (not shown) are mounted inside the cavity 23 constituted by the above. In this example, an example is shown in which the mounting portion inside the cavity 23 is formed in a flat surface shape.
The mounting portion may be formed in a concave shape. afterwards,
By attaching a lid (not shown) made of metal or the like to the upper surface of the wall member 22 by soldering, welding, or the like, a high-frequency semiconductor device is formed, and the high-frequency semiconductor element or high-frequency electronic circuit housed therein is protected from external disturbance. It will protect you.

Reference numeral 24 denotes a feed for supplying power from an external electric circuit board or the like or supplying a low frequency such as a control signal, which is fixed by brazing or the like by cutting out a part of the wall member 22. 25 is a through-hole, and a part of the wall member 22 is also cut out, and the bottom surface thereof, that is, the upper surface of the substrate 21 corresponding to the part is fitted to the input / output terminal mounting portion having conductivity, and is fixed by brazing or the like. High-frequency input / output terminal 5.

The bottom surface of the input / output terminal mounting portion is
And when the wall member 22 is made of metal, it is conductive,
When the substrate 21 and the wall member 22 are made of a dielectric material, they may be made conductive by applying a conductive layer. The conductive bottom surface is grounded by a suitable means (not shown).

According to the first high frequency semiconductor device package of the present invention, a so-called metal wall type high frequency semiconductor device package is obtained.

In this embodiment, the high frequency input / output terminals 25 are attached to both sides of the wall member 22 one by one. However, if necessary, a plurality of terminals may be attached to other positions or to one side. In this case, a plurality of input / output terminal attachment portions may be provided, and a plurality of high frequency input / output terminals 25 may be attached in parallel.

The high frequency input / output terminal 25 includes a hermetic seal portion 25a composed of a dielectric substrate 26 and a dielectric wall member 27 joined to the upper surface thereof, and a dielectric substrate 26 and a dielectric wall member 27. It has a signal line 25b formed on the dielectric substrate 26 so as to penetrate the hermetic seal portion 25a with a part thereof sandwiched therebetween, and a ground conductor layer 25c formed on the lower surface of the dielectric substrate 26. The signal line 25b is DC-insulated from the substrate 21 and the wall member 22, which serve as grounds.

In the high frequency input / output terminal 25,
The signal line 25b includes a main conductor layer 28 made of a metalized conductor layer of a refractory metal such as tungsten or molybdenum formed on the upper surface of the dielectric substrate 26, and a surface exposed from the hermetic seal portion 25a of the main conductor layer 28. A first plating layer 29 mainly composed of nickel and a dielectric wall member 27;
A moisture-resistant insulating coating material covering the main conductor layer 28 and the first plating layer 29 in a range of 0.3 mm or more and 2 mm or less from the wall surface of the main conductor layer 28, that is, in a range where L shown in FIG.
31 and a second plating layer 30 mainly composed of gold and deposited on the exposed surface of the first plating layer.

Thus, as is apparent in FIG.
The portion where the first plating layer 29 does not sufficiently cover the wall of the dielectric wall member 27 with respect to the main conductor layer 28 of the signal line 25b, that is, the range of 0.3 mm or more and 2 mm or less from the wall surface of the dielectric wall member 27 is moisture-resistant insulating coating By covering with material 31,
The gold of the second plating layer 30 deposited on the surface of the plating layer 29 does not come into direct contact with tungsten or molybdenum which is a high melting point metal of the main conductor layer 28. Since it is covered with the insulating covering material 31, the moisture becomes an electrolyte and does not come into contact with the electrolyte.

Further, even if moisture enters through the moisture-resistant insulating covering material 31, the second plating layer 30 and the main conductor layer 28
Since there is a distance covered by the moisture-resistant insulating covering material 31 between them, the possibility of contact between the two via the electrolyte is extremely small, and the possibility of a reaction occurring is also extremely low.

As a result, even in a high-temperature, high-humidity atmosphere, the main conductor layer 28 does not corrode and break the signal line 25b as in the prior art, and has excellent moisture resistance characteristics. Can be kept.

Further, since the basic structure of the signal line 25b is substantially the same as the conventional one, the reflection of the high-frequency signal does not increase in the hermetic seal portion 25a, and the high-frequency characteristics are small and the transmission loss is small. .

In the high frequency input / output terminal 25 of the present invention,
As the dielectric substrate 26 and the dielectric wall member 27, for example, a ceramic material such as alumina ceramics or mullite ceramics, or a material such as glass ceramics on which a main conductor layer 28 made of a high melting point metal is formed, is used. The thickness, width, and length are appropriately set according to the frequency, characteristic impedance, and the like of the transmitted high-frequency signal.

In particular, it is preferable that the thickness of the dielectric wall member 27 is relatively thin, for example, about 0.2 to 1.0 mm, and it is preferable that the dielectric wall member 27 be thicker than the dielectric substrate 26. And the resonance frequency can be increased, and the high-frequency characteristics are further improved. If the thickness of the dielectric wall member 27 is less than 0.2 mm, the actual production tends to be difficult, while
When the value exceeds, the dielectric loss increases, the transmission loss increases, and slot resonance tends to occur, so that the resonance frequency cannot be easily increased.

The same material as the dielectric substrate 26 may be used for the dielectric wall member 27. However, the dielectric constant of the dielectric wall member 27 and the dielectric constant of the dielectric substrate 26 are made different by using different materials. Is also good. In this case, for example, the dielectric constant of the dielectric wall member 27 is preferably lower than that of the dielectric substrate 26.
It is preferable to make the permittivity of 27 as close as possible to the vacuum permittivity, so that the change in the propagation mode at the junction between the dielectric substrate 26 and the dielectric wall member 27 and the other portions is small, and the transmission loss is reduced. Is preferred in that the value is smaller.

The main conductor layer 28 constituting the signal line 25b is made of a high melting point metal such as tungsten, molybdenum / manganese, or an alloy thereof, and is formed on the upper surface of the dielectric substrate 26 by an ordinary metallization method such as a thick film printing method. Is done. The thickness and the width are appropriately set according to the frequency and characteristic impedance of the transmitted high-frequency signal, and the thickness is usually set to about 5 to 20 μm.

The ground conductor layer 25c is made of the same metal material as the main conductor layer 28 of the signal line 25b or a metal material for high-frequency line conductors, such as copper, chromium, tantalum nitride, nichrome, titanium, palladium, or an alloy thereof. Are formed by a thick film printing method, various thin film forming methods, plating methods, and the like, and the thickness and width thereof are appropriately set according to the frequency and characteristic impedance of the transmitted high-frequency signal.

The ground conductor layer 25c may be formed by attaching a metal plate or a metal block in addition to the case where the ground conductor layer 25c is formed as a metal coating layer as described above.

The first plating layer 29 is mainly composed of nickel, and a metal such as a nickel-cobalt alloy may be used in addition to nickel. The main conductor layer is formed by a usual electrolytic plating method or electroless plating method. Deposited on 28 exposed surfaces.

The thickness of the first plating layer 29 is usually 1 to 3
The thickness is set to about μm, and within this range, the adhesion of the second plating layer 30 of gold plating is good, and peeling or blistering does not occur even in a chip or the like mounting process. This thickness is 1 μm
If it is less than 3 μm, the adhesion to the second plating layer 30 tends to be insufficient. On the other hand, if it exceeds 3 μm, peeling or blistering of the plating tends to easily occur in a later step.

The main conductor layer 28 near the wall of the dielectric wall member 27
In order to effectively cover the portion where the first plating layer 29 did not sufficiently cover the exposed surface of the substrate with the moisture-resistant insulating covering material 31, the first plating layer 29 uses the dielectric wall member 27 as much as possible.
It is preferable to sufficiently cover a range of less than 2 mm from the wall surface of the device, and for this purpose, it is preferable to use a micro-discharge device such as a dispenser.

As the moisture-resistant insulating coating material 31, it is necessary to use a water-resistant material which has strong adhesion to the first plating layer 29 and is not exposed to a plating solution or the like. For example, there are glasses such as borosilicate glass and aluminoborosilicate glass and resins such as epoxy and polyimide. The main conductor layer 28 is made of these materials.
And to cover the exposed surface of the first plating layer 29 from the wall surface of the dielectric wall member 27 in a range of 0.3 mm or more and 2 mm or less,
For example, a minute discharge device such as a dispenser may be used.

The thickness of the moisture-resistant insulating covering material 31 is appropriately set according to the material used and the specifications of the high-frequency input / output terminals and the high-frequency semiconductor device package.
For example, a thickness of 50 μm or less is preferable from the viewpoint of affecting high frequency characteristics.

The width of the moisture-resistant insulating covering material 31 may be set so as to sufficiently cover the width of the main conductor layer 28 and the first plating layer 29.

Further, a material made of glass having a dielectric constant of 5 or less, a coefficient of thermal expansion within a range of 7 to 10 ppm / ° C., and a softening temperature of 1200 ° C. or less is used as the moisture-resistant insulating covering material 31. , Dielectric substrate 26 and dielectric wall member 27
Adhesion with the alumina ceramic used in the first step is strong, the influence on the first plating layer 29 is small, and good high-frequency characteristics are obtained. As such a glass, for example, borosilicate glass or the like can be used.

The second plating layer 30 is mainly composed of gold, and is deposited on the exposed surface of the first plating layer 29 by a usual electrolytic plating method or an electroless plating method.

The thickness of the second plating layer 30 is usually 1 to 5
It is set to about μm, and within this range, good wire bonding characteristics can be obtained. This thickness is 1μ
If it is less than m, the wire bonding strength tends to decrease, while if it exceeds 5 μm, peeling and blistering tend to occur in a later step.

In order to avoid contact between the second plating layer 30 and the main conductor layer 28 which is a metallized conductor layer and to block moisture serving as an electrolyte, the first plating layer 31 covered with a moisture-resistant insulating coating material 31 is used. It is preferable to sufficiently cover the exposed surface of the layer 29 up to the portion covered with the moisture-resistant insulating covering material 31, and for this purpose, a small-volume discharge device such as a dispenser may be used.

Next, according to the second high-frequency semiconductor device package of the present invention, the lower surface has a ground conductor similar to the above-described ground conductor 25c, and the high-frequency semiconductor element or the high-frequency electronic circuit is mounted on the upper surface. A dielectric substrate made of the same material as the above-described dielectric substrate 26, and a signal line formed on the upper surface of the dielectric substrate from near the mounting portion to near the outer periphery of the dielectric substrate. A signal line similar to 25b and a shape similar to the above-described frame-shaped wall member 22 that surrounds the mounting portion on the dielectric substrate and is sandwiched with a part of the signal line interposed therebetween (however, the high-frequency input / output terminals 25 There is no notch as a mounting part of), a frame-shaped dielectric wall member of
This signal line has a main conductor layer similar to the above-described main conductor layer 28, a first plating layer similar to the above-described first plating layer 29, and a range of 0.3 mm or more and 2 mm or less from the wall surface of the dielectric wall member. The same moisture-resistant insulation coating material as the above-described moisture-resistant insulation coating material 31 covering the main conductor layer and the first plating layer, and the same as the above-described second plating layer 30 applied to the exposed surface of the first plating layer. Of the second plating layer.

According to the second high-frequency semiconductor device package of the present invention having such a configuration, a high-frequency signal input / output terminal having the same configuration as the high-frequency input / output terminal 25 of the present invention is provided. Therefore, the portion where the first plating layer does not sufficiently cover the wall of the dielectric wall member with respect to the main conductor layer of the signal line, that is, 0.3 mm or more and 2 m from the wall surface of the dielectric wall member.
By covering the range of m or less with the moisture-resistant insulating coating material, the gold of the second plating layer subsequently deposited on the surface of the first plating layer and the refractory metal of the main conductor layer do not come into direct contact with each other, Further, even if dew condensation occurs in this portion, since the portion is covered with the moisture-resistant insulating coating material, moisture becomes an electrolyte and does not come into contact with the electrolyte.

Even if moisture penetrates through the moisture-resistant insulating covering material, there is a distance between the second plating layer and the main conductor layer that is covered by the moisture-resistant insulating covering material. In addition, the possibility of contact between the two via the electrolyte is extremely small, and the possibility of a reaction occurring is also extremely low.

As a result, even in a high-temperature, high-humidity atmosphere, the main conductor layer is not corroded as in the prior art, and the signal line is not broken. Can be.

Since the basic structure of the signal line is almost the same as that of the conventional one, the reflection of the high-frequency signal does not increase in the hermetic seal portion, and the package for the high-frequency semiconductor device having good high-frequency characteristics with small transmission loss. Becomes

Further, the moisture-resistant insulating coating material in this case also has a dielectric constant of 5 or less and a thermal expansion coefficient of 7 to 10 ppm /
By using a glass material having a softening temperature of 1200 ° C. or lower within the range of ° C., the coating can be performed without adversely affecting the first plating layer 29, so that the adhesion is good, and the dielectric substrate 26 and the dielectric Since the thermal expansion coefficient matches that of the alumina ceramic used for the body wall member 27, no cracks are formed, and as a result, moisture is completely blocked.

According to the second high-frequency semiconductor device package of the present invention, the bonding wire or the ribbon is connected to the terminal electrode of the high-frequency semiconductor element or the like mounted on the mounting portion and the wiring conductor of the external electric circuit. The high frequency semiconductor element and the like inside the package are electrically connected to each other and the external electric circuit, and the lid is attached to the upper surface of the dielectric wall member. And is housed in a hermetically sealed manner to provide a high-frequency semiconductor device as a product.

As the dielectric substrate and the dielectric frame, a dielectric similar to the above-described dielectric of the high frequency input / output terminal according to the present invention may be used according to the specifications of the package. Further, it is desirable to form a ground conductor layer on almost the entire lower surface of the dielectric substrate from the viewpoint that the ground conductor layer needs to be in an ideal ground state.

In addition to joining the dielectric substrate and the dielectric frame separately manufactured, for example, the dielectric substrate and the ceramic green sheet which becomes the dielectric frame after firing are laminated and fired. And may be joined by being integrated.

The dielectric constant of the portion of the dielectric wall member corresponding to the high-frequency input / output terminal is made different from that of the other portions of the dielectric wall member, for example, by making it low, so that the hermetic seal portion and the front and rear portions thereof can be removed. By making the propagation mode of the high-frequency signal closer, the reflection loss and the insertion loss can be effectively reduced.

A plurality of high frequency input / output terminals may be provided at desired positions as necessary. The ground conductor layer may be formed as a metal coating layer, or may be formed by attaching a metal plate or a metal block. May be formed.

[0067]

Next, specific examples of the high frequency input / output terminal and the high frequency semiconductor device package according to the present invention will be described.

Example 1 FIGS. 3 and 4 show a so-called metal wall type high frequency semiconductor device package.
The package sample A for a high-frequency semiconductor device provided with the high-frequency input / output terminal having the conventional structure shown in FIG. 1 and the hermetic seal portion of the high-frequency input / output terminal described as a countermeasure for the problem to be solved by the invention A package sample B for a high-frequency semiconductor device having a high-frequency input / output terminal having a structure bypassed by using an inner layer line conductor and a via conductor, and a book having the high-frequency input / output terminal of the present invention shown in FIGS. Each of the first package samples for a high-frequency semiconductor device of the invention was manufactured.

Here, the external size (size of the substrate) of the high-frequency semiconductor device package is 2 cm × 3 cm, and the size of the high-frequency input / output terminals is 1 mm wide × 3 mm long × 1 height.
mm (dielectric substrate is 1mm wide x 3mm long x 0.5m high)
m, dielectric wall member is 1mm wide x 0.7mm long x 0.35 height
mm). Copper is used for the package substrate and the frame-shaped wall member, alumina ceramic is used for the dielectric substrate and the dielectric wall member of the high frequency input / output terminal, tungsten is used for the main conductor layer of the signal line, and nickel is used. The thickness of the plating layer (first plating layer) was 2 μm, and the thickness of the gold plating layer (second plating layer) was 1.5 μm.

The package sample for a high-frequency semiconductor device of the present invention is made of an epoxy resin and a borosilicate glass having a relative dielectric constant of 5.0 (softening temperature: 950 ° C.) as a moisture-resistant insulating coating material.
The range in which the moisture-resistant insulating covering material covers the signal line is 0.2 mm, 0.4 mm, 1 mm, 1.8 mm, 2.3 mm, and 2.3 mm, including the sample as a comparative example.
Fourteen types of samples C to P were prepared as 3 mm / 5 mm samples.

Then, five samples were selected for each of the package samples of each structure, and left for 1000 to 3000 hours in an environment of a temperature of 85 ° C. and a humidity of 85% RH. The occurrence of disconnection due to corrosion was examined. The insertion loss at 40 GHz of each sample was examined as the high-frequency transmission characteristics of the high-frequency input / output terminals. Table 1 shows the number (pieces) of disconnection occurring after each time and the value (dB) of insertion loss. The insertion loss was determined to be good when the insertion loss was 0.5 dB or less.

[0072]

[Table 1]

As can be seen from Table 1, in Sample A, one wire was broken after 2000 hours, and after 3000 hours, three wires were broken. In Sample C as a comparative example of the present invention, two wires were broken after 2000 hours.
Three after 3000 hours, one for sample J after 2000 hours, 3000
After 4 hours, disconnection occurred in 4 pieces, whereas in sample B and samples D to FK to M of the present invention and samples G to IN and P of the comparative example, sample D 1 after 2000 hours, 1 after 3000 hours for sample E, 3000 for sample K
0 hours after the occurrence of disconnection was observed, and according to the sample B and the sample in which the covering range of the moisture-resistant insulating coating material was 0.3 mm or more in the high-frequency input / output terminal of the structure of the present invention, the conventional structure was used. It can be seen that the reliability is high even under high temperature and high humidity.

On the other hand, the insertion loss of sample B was as large as 35 dB, and that of samples G to I.N to P, which are comparative examples, exceeded 0.5 dB. 0.4 dB for all samples D to FK to M
It can be seen that the insertion loss is as small as below, and the insertion loss is almost the same as that of the sample A having the conventional structure.

Example 2 Next, the composition of glass as a moisture-resistant insulating coating material was adjusted so that the coefficient of thermal expansion was 5 ppm · 7 pp.
Glasses of m, 10 ppm, and 15 ppm were prepared, and using these, a package sample for a high-frequency semiconductor device having the same high-frequency input / output terminal of the present invention as in Example 1 was produced.
The softening temperature of these glasses was 900 to 1050 ° C. Then, these samples were subjected to -65 ° C to 200 ° C, 50
A temperature cycle test was performed under 0 cycle conditions, and the presence or absence of cracks was confirmed for each of the moisture-resistant insulating coating materials.

As a result, when the dielectric substrate was made of alumina ceramics, no cracks were observed in the samples having the thermal expansion coefficients of 7 ppm and 10 ppm, and the samples had high reliability in the temperature cycle test. It could be confirmed. Slight cracks were observed in the samples having a thermal expansion coefficient of 5 ppm and 15 ppm, but all of these were practically acceptable.

Example 3 Next, the composition of glass as a moisture-resistant insulating coating material was adjusted so that the relative dielectric constant was 4.8 · 10 ·
Thirty glasses were prepared, and the covering range of the moisture-resistant insulating covering material was set to 1.0 mm ± 0.5 mm using the same. A package for a high-frequency semiconductor device having the same high-frequency input / output terminal of the present invention as in [Example 1] A sample was prepared. The softening temperatures of these glasses were 980 ° C, 500 ° C, and 450 ° C, respectively. For these samples, the insertion loss at 40 GHz was examined as the high-frequency transmission characteristics of the high-frequency input / output terminals.

As a result, the sample having a relative dielectric constant of 30 was 0.5 d
B, while the sample with a relative dielectric constant of 10 was 0.5 dB, the sample with a relative dielectric constant of 4.8 had an extremely low insertion loss of 0.3 dB, confirming that it had particularly good high-frequency transmission characteristics. Was.

Further, a second high-frequency semiconductor device package sample of the present invention having the same high-frequency input / output terminal portions as the samples of the present invention in Examples 1 to 3 was prepared. When the same evaluation was performed as described above, almost the same good results were obtained.

As shown in the above embodiments, the high frequency input / output terminal and the high frequency semiconductor device package of the present invention have excellent moisture resistance, excellent reliability under high temperature and high humidity, and excellent high frequency characteristics. It was confirmed that it was.

The above is merely an example of the embodiment of the present invention, and the present invention is not limited to the embodiment. Various changes and improvements may be made without departing from the gist of the present invention. No problem. For example, polyimide or the like may be used as the resin material.

[0082]

As described above, according to the high frequency input / output terminal and the high frequency semiconductor device package of the present invention, the exposed surface of the main conductor layer of the signal line near the wall of the dielectric wall member has
A first plating layer containing nickel as a main component is applied, and the main conductor layer and the first plating layer are covered with a moisture-resistant insulating coating material in a range of 0.3 mm or more and 2 mm or less from the wall surface of the dielectric wall member. Since the second plating layer mainly composed of gold was applied to the exposed surface of the first plating layer, there was a portion where the nickel plating was not sufficiently applied to the main conductor layer near the wall of the dielectric wall member. However, by covering the portion with a moisture-resistant insulating coating material, it is possible to avoid direct contact between the main conductor layer made of a high melting point metal and the gold plating layer and through an electrolyte such as dew condensation. The signal line did not corrode or break, the moisture resistance was significantly improved as compared to the conventional structure, and the reflection of high-frequency signals was small and the insertion loss was small.

According to the high frequency input / output terminal and the high frequency semiconductor device package of the present invention, the moisture-resistant insulating coating material has a dielectric constant of 5 or less and a thermal expansion coefficient of 7 to 10%.
When a glass having a softening temperature of 1200 ° C. or less in the range of ppm / ° C. is used, the glass has excellent moisture resistance and the main conductor layer is completely removed from the dew condensation or the like near the wall surface of the dielectric wall member. At the same time, the thermal expansion coefficient is close to that of ceramics such as alumina ceramics, which have excellent properties as a dielectric substrate, so there is no cracking or peeling even if a thermal cycle load is applied, and high reliability can be achieved. ,
Furthermore, the high frequency transmission characteristics were excellent.

As described above, according to the present invention, the input / output terminal for high frequency with improved humidity resistance and high loss of the high frequency signal and the high reliability and high frequency with improved moisture resistance are improved. A high-frequency semiconductor device package using a high-frequency input / output terminal having a small signal loss or having such a high-frequency input / output terminal can be provided.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing an example of an embodiment of a high frequency input / output terminal and a high frequency semiconductor device package of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the high frequency input / output terminal of FIG.

FIG. 3 is a partially cutaway perspective view showing an example of a conventional high frequency input / output terminal and a conventional high frequency semiconductor device package.

FIG. 4 is an enlarged sectional view of a main part of the high frequency input / output terminal of FIG. 3;

[Explanation of symbols]

 21 ··· Substrate 22 ···· Wall member 25 ··· High frequency input / output terminal 25b ···· Signal line 25c ··· Ground conductor layer 26 ····· Dielectric substrate 27 dielectric wall member 28 main conductor layer 29 first plating layer 30 second plating layer 31 moisture resistant insulation coating material

Claims (5)

[Claims] 1. A high-frequency input comprising a dielectric substrate having a ground conductor layer on a lower surface and a signal line formed on an upper surface, and a dielectric wall member joined to an upper surface of the dielectric substrate with a part of the signal line interposed therebetween. In the output terminal, the signal line includes: a main conductor layer made of a high melting point metal; a first plating layer mainly composed of nickel deposited on an exposed surface of the main conductor layer; and a wall surface of the dielectric wall member. A moisture-resistant insulating coating material covering the main conductor layer and the first plating layer in a range of 0.3 mm or more and 2 mm or less, and a first layer mainly composed of gold deposited on an exposed surface of the first plating layer. A high frequency input / output terminal comprising two plating layers. 2. The moisture-resistant insulating coating material is made of glass having a dielectric constant of 5 or less, a coefficient of thermal expansion in a range of 7 to 10 ppm / ° C., and a softening temperature of 1200 ° C. or less. The high frequency input / output terminal according to claim 1. 3. A substrate having a mounting portion for mounting a high-frequency semiconductor element or a high-frequency electronic circuit on an upper surface, a frame-shaped wall member joined to the substrate so as to surround the mounting portion, and the wall. An input / output terminal mounting portion formed by cutting out a member and having a conductive bottom surface, and a high frequency input / output terminal according to claim 1 or 2 fitted to the input / output terminal mounting portion. A package for a high-frequency semiconductor device, comprising: 4. A dielectric substrate having a ground conductor on a lower surface and a mounting portion for mounting a high-frequency semiconductor element or a high-frequency electronic circuit on an upper surface, and a dielectric on the upper surface of the dielectric substrate from near the mounting portion. A signal line formed around the outer periphery of the body substrate, and a frame-shaped dielectric wall member joined to the dielectric substrate so as to surround the mounting portion and sandwich a part of the signal line, The signal line has a main conductor layer made of a high melting point metal, a first plating layer mainly composed of nickel applied to an exposed surface of the main conductor layer, and 0.3 mm or more from a wall surface of the dielectric wall member. A moisture-resistant insulating coating material covering the main conductor layer and the first plating layer in a range of 2 mm or less, and a second plating layer mainly composed of gold, which is deposited on an exposed surface of the first plating layer. For high frequency semiconductor devices characterized by the following: package. 5. The moisture-resistant insulating coating material is made of glass having a dielectric constant of 5 or less, a coefficient of thermal expansion within a range of 7 to 10 ppm / ° C., and a softening temperature of 1200 ° C. or less. The package for a high-frequency semiconductor device according to claim 4.