JP3451038B2 - Dielectric circuit board and millimeter-wave semiconductor device including the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric circuit board for mounting a millimeter wave semiconductor element in a face-down form, and a millimeter wave semiconductor device formed by mounting the millimeter wave semiconductor element on the dielectric circuit board. It is a thing.

[0002]

(Background) In recent years, as the processing speed of information processing devices has increased and the resolution of image processing devices has increased,
Large-capacity ultra-high-speed wireless communication in the millimeter wave band of up to 300 GHz is drawing attention. A high-performance millimeter-wave semiconductor device is indispensable to construct a millimeter-wave band wireless communication device.
A millimeter wave semiconductor device is obtained by mounting a millimeter wave semiconductor element on a dielectric circuit board having a circuit pattern formed on the surface thereof.

However, when the millimeter wave semiconductor element is electrically connected to the dielectric circuit board by the wire bond method which has been widely used for mounting semiconductor devices, signal terminals and circuits are used. There is a problem that signal attenuation is increased due to the influence of the inductance of the metal wire connecting to the board terminal, and desired characteristics cannot be obtained. Therefore, as a mounting method of a millimeter wave semiconductor element, there is a method of facing the element surface toward the dielectric circuit board side, such as a flip-chip bonding method using a protruding electrode, a method of reducing inductance by so-called face down. Often used.

However, in such a face-down mounting method, when the surface of the dielectric circuit substrate facing the millimeter wave semiconductor element is basically made of a conductor, the distance is generally several μm to several tens μm, and the impedance In order to reduce the
It will be difficult.

For this reason, the conductor provided on the surface of the dielectric circuit board facing the millimeter wave semiconductor element is limited to the minimum necessary conductor, and the ground conductor is placed with a dielectric layer of a predetermined thickness separated. As a result, a large mounting margin can be secured for the impedance shift. The ground conductor is placed on the back surface if the dielectric substrate is a double-sided board, and on the inner layer or the back surface if the dielectric substrate is a multilayer board.
Hereinafter, this ground conductor will be referred to as a "back surface ground conductor".

Further, in this case, the grounding conductor provided on the millimeter wave semiconductor element is electrically connected to the grounding conductor provided on the surface of the dielectric substrate through, for example, the protruding electrode, and the grounding conductor on the surface is grounded. The body is connected to the backside ground conductor through a via hole having the conductor filled therein. If the path length from the millimeter-wave semiconductor element becomes longer than a certain length, the function of the back-side grounded conductor as the grounded conductor of the millimeter-wave semiconductor element at high frequencies will deteriorate. Therefore, in order to avoid this functional deterioration, the via hole is arranged in the millimeter wave semiconductor element mounting portion. In particular, in order to reduce the path length, it is often placed directly below the bump electrode. Therefore, generally, the arrangement of the via holes follows the arrangement of the protruding electrodes arranged in the peripheral portion of the millimeter wave semiconductor element, and has a rectangular shape that is substantially along the shape of the millimeter wave semiconductor element.

(Example of Conventional Millimeter Wave Semiconductor Device) FIG.
14 to 14, an example of a conventional millimeter wave semiconductor device using the flip chip bonding method will be described.

FIG. 12 is a plan view showing a dielectric circuit board 2 on which a circuit pattern 4 for mounting the millimeter wave semiconductor element 3 by a flip chip bonding method is formed. However, in FIG. 12, the dielectric portion 20 (see FIG. 14) of the dielectric circuit board 2 is omitted. A circuit pattern 4 made of a conductive material is formed on the main surface of the dielectric circuit board 2 made of a dielectric material such as ceramic, that is, a surface on which the millimeter wave semiconductor element is mounted, and a high frequency signal transmission characteristic is improved on the surface. For the purpose, it is plated with gold. In the example shown in FIG. 12, as the circuit pattern 4,
A signal input / output terminal 4a and a ground potential pattern 4b are formed. The millimeter wave semiconductor element mounting portion 7 is an area where the millimeter wave semiconductor element 3 is mounted. The via holes 6 are arranged in a rectangular shape following the shape of the mounted millimeter-wave semiconductor element 3, and are normally arranged at regular intervals on a fixed line.

FIG. 13 is a plan view showing the millimeter wave semiconductor device 3 having the protruding electrodes 10 formed thereon. However, it is a plan view of the lower surface seen through from above rather than from below. G
The millimeter-wave semiconductor element 3 made of a material such as aAs has a circuit (not shown) of a millimeter-wave device formed on the circuit formation surface by a wafer process technique, and a bonding pad 9 is provided as a signal input / output terminal 12. Further, on the bonding pad 9, a protruding electrode 10 made of gold or the like is formed.

FIG. 14 is a sectional view taken along line II-II showing the millimeter wave semiconductor device 1 in which the millimeter wave semiconductor element 3 of FIG. 13 is mounted on the dielectric circuit board 2 of FIG. 12 by the flip chip bonding method. Is. A potential pattern 5 for grounding (hereinafter, referred to as "rear surface ground potential pattern") 5 is basically formed on the entire back surface of the dielectric circuit board 2. The ground potential pattern 4b on the front surface and the ground potential pattern 5 on the back surface are connected by a via hole 6 in which a conductor is filled.

When the millimeter wave semiconductor device 1 is assembled, the projecting electrodes 10 are connected to the circuit by thermocompression bonding so that the circuit forming surface of the millimeter wave semiconductor element and the circuit pattern 4 of the dielectric circuit board face each other. It is bonded to the millimeter wave semiconductor element mounting portion 7 on the surface of the pattern 4. After that, the millimeter-wave semiconductor device 1 is hermetically sealed to protect the external environment, and a millimeter-wave signal transmitting / receiving antenna is further formed as necessary.

[0012]

In the millimeter wave semiconductor device 1 in which the millimeter wave semiconductor element 3 is mounted on the dielectric circuit board 2 by face down of the conventional structure, as described above, the via holes 6 are arranged in the millimeter wave. The via hole 6 has a rectangular shape following the outer shape of the semiconductor element 3 and is normally arranged on a fixed line at regular intervals.
The positional relationship such as the distance and direction between the via holes in each part of the arrangement is the same. As a result, the resonance frequencies of the respective parts are almost the same. Therefore, when a resonance depending on the positional relationship occurs, repetition of the similar positional relationship amplifies the resonance to a greater extent and propagates it further. As a result, depending on the design of the used frequency and the circuit pattern, a significant level variation distribution may occur in the used frequency band due to resonance, which may adversely affect the characteristics of the millimeter wave semiconductor device 1.

FIG. 15 is a schematic diagram showing an example of high frequency characteristics of the millimeter wave semiconductor device 1 shown in FIGS. The vertical axis represents frequency and the vertical axis represents high-frequency characteristics. The shaded areas F1 to F2 are frequency bands used, and the lowest level of high-frequency characteristics that can be used (hereinafter referred to as "usable minimum level"). T1 is set. There is no problem if the high frequency characteristics are better than the lowest usable level T1 in the used frequency band.

The high frequency characteristics of the conventional millimeter wave semiconductor device 1 tend to gradually deteriorate as the frequency increases. Further, deterioration having a locally sharp peak is seen at frequencies F3, F4, and F5. These F3, F4, F
The frequency at which the high frequency characteristic locally deteriorates, such as 5, is hereinafter referred to as "local deterioration frequency". Of the locally deteriorated frequencies, F4 is within the usable frequency band and is below the lowest usable level T1, and therefore adversely affects the use of the millimeter wave semiconductor device 1.

The present invention has been made in order to solve the above-mentioned problems, and when a millimeter-wave semiconductor device is constructed, a dielectric circuit substrate in which high frequency characteristics are not adversely affected by amplification and propagation of resonance, Another object of the present invention is to provide a millimeter wave semiconductor device using the same.

[0016]

In order to achieve the above object, in one aspect of a dielectric circuit board according to the present invention, a dielectric capable of forming a millimeter wave semiconductor device by mounting a millimeter wave semiconductor element. a circuit board having a via hole rows arranged in correspondence with the respective sides of the mounting region of the millimeter wave semiconductor devices, the via hole column, a via hole containing therein a grounded conductor is in alignment They are arranged so that they will not be listed. Or In another aspect, a formable dielectric circuit board millimeter wave semiconductor device by implementing a millimeter wave semiconductor devices, are arranged to correspond to the respective sides of the mounting region of the millimeter wave semiconductor devices There is a via hole array, and the via hole array is such that via holes including a grounded conductor inside are arranged such that the distance between adjacent via holes is not constant.

By adopting the above-mentioned structure, the positional relationship between the via holes 6 is messed up and diversified, and the resonance frequency is different for each part. as a result,
Many other parts resonate in response to resonance at a certain frequency,
The phenomenon of amplification and propagation is less likely to occur.

In the above invention, preferably, the distance between any two of the via holes arranged adjacent to each other is less than 1/2 of the effective wavelength on the substrate surface.

By adopting the above configuration, the distance between the via holes arranged adjacent to each other is less than 1/2 of the effective wavelength, and therefore, the electromagnetic wave between the portion surrounded by the via holes and the outside thereof. Effective shutoff.

Further, in the above invention, preferably, from any one of the above-mentioned via holes, two adjacent vias are provided on both sides of the via hole.
The via holes are arranged such that the distance to one of the via holes and the distance to the other are different from each other. With this configuration, the probability that the resonance frequencies are different is increased, so that amplification and propagation are easily suppressed.

Further, in the above invention, preferably, from the central via hole within a distance of 1/2 or less of the effective wavelength on the substrate surface from the central via hole which is one via hole arbitrarily selected from the above via holes. The number of other via holes whose distances are substantially equal to each other is 3 or less. With this configuration, amplification and propagation of resonance due to the distance are suppressed.

Further, in the above invention, preferably, from the midpoint of a line segment formed by connecting the centers of two via holes adjacent to each other arbitrarily selected from the via holes, from the midpoint of the effective wavelength on the substrate surface, Within the range of the distance of 2 or less, the number of other via holes that intersect the straight line formed by extending the line segment is 2 or less.

By adopting the above-mentioned structure, the propagation of resonance, which tends to travel straight, can be suppressed because the number of via holes arranged in the direction of straight travel is reduced.

[0024] In the dielectric circuit other aspects of the substrate according to the present invention, there is provided a formable dielectric circuit board millimeter wave semiconductor device by implementing a millimeter-wave semiconductor device, a via hole rows that are sequence The via hole array is an array of via holes including a grounded conductor therein, and the via hole array is arranged in a substantially arc shape.
The major axis of the arc of each of the above-mentioned substantially arc-shaped portions is less than 1/2 of the effective wavelength on the surface of the substrate.

By adopting the above structure, the frequency of resonance generated in each substantially arcuate portion can be made relatively high. As a result, it is possible to prevent the high frequency characteristic from falling below the usable level in the used frequency band.

[0026] In yet another aspect of the dielectric circuit board according to the present invention, there is provided a formable dielectric circuit board millimeter wave semiconductor device by implementing a millimeter wave semiconductor devices, arrays and via holes column And the via hole array is an array of via holes including a grounded conductor therein, and the via hole array includes a substantially rectangular portion composed of four or more via holes arranged in a substantially rectangular shape. The length of the rectangular long side of each of the rectangular portions is less than 1/2 of the effective wavelength on the substrate surface.

By adopting the above structure, the frequency of resonance generated in each substantially rectangular portion can be made relatively high. As a result, it is possible to prevent the high frequency characteristic from falling below the usable level in the used frequency band.

[0028] In still another aspect of the dielectric circuit board according to the present invention, the via hole array includes a parallel via hole array along a plurality of substantially parallel straight lines, and each of the parallel via hole arrays extends along each straight line. The via holes arranged in parallel are arranged at unequal intervals.

By adopting the above structure, the resonance frequency can be made relatively high. as a result,
It is possible to prevent the high frequency characteristic from falling below the usable level in the used frequency band.

One aspect of the millimeter wave semiconductor device according to the present invention includes the above-mentioned dielectric circuit board on which a millimeter wave semiconductor element is mounted. With this configuration, it is possible to provide a millimeter-wave semiconductor device whose high-frequency characteristics are not lower than the lowest usable level in the frequency band used.

In another aspect of the millimeter wave semiconductor device according to the present invention, a millimeter wave semiconductor element whose outer edge portion is surrounded by a plurality of linearly arranged protruding electrode rows is mounted on a dielectric circuit board. a wave semiconductor device, a via hole of the dielectric circuit board, in the vicinity of each of the protruding electrode array has a bi Aho <br/> Le columns, the via hole column containing therein a grounded conductor Are arranged so as not to be placed on a straight line parallel to the corresponding protruding electrode row.

With the above structure, it is possible to provide a millimeter-wave semiconductor device in which the high-frequency characteristics do not fall below the lowest usable level in the operating frequency band.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1) (Structure) With reference to FIGS. 1 to 3, the structure of a millimeter wave semiconductor device 1 on which a dielectric circuit board 2 according to the present embodiment is mounted will be described. As the dielectric portion 20 of the dielectric circuit board 2 in the present embodiment, the material is ceramics, the plate thickness is 150 μm, and the relative dielectric constant is about 9.

FIG. 1 shows a plan view of the dielectric circuit board 2. However, in FIG. 1, the dielectric portion 20 of the dielectric circuit board 2 is omitted. A circuit pattern 4 for mounting a millimeter wave semiconductor element is formed on one surface, which is the main surface of the dielectric circuit board 2. The circuit pattern 4 includes a signal input / output pattern 4a and a ground potential pattern 4b. The circuit pattern 4 is a via hole 6 for shielding electromagnetic waves.
The via hole array 60 having the arrangement of is arranged corresponding to each side so as to substantially surround the millimeter wave semiconductor element mounting portion 7 as the mounting area of the millimeter wave semiconductor element. Via holes 6 arranged adjacent to each other in the via hole row 60
The distance L1 between them is less than 1/2 of the effective wavelength. Here, the "effective wavelength" means the effective wavelength on the surface of the dielectric substrate, and the effective wavelength is the dielectric constant of the substance such as air or resin in contact with the dielectric substrate, the shape or material of the circuit pattern, etc. It is a value determined from. The same applies to the description below in the case of "effective wavelength".

Further, the via holes 6 in the via hole array 60 are arranged in a shape (non-linear unevenness) that does not fit on a straight line on each side when viewed from the top surface.

As shown in FIG. 1, the distance between the via holes 6 sandwiching the signal input / output pattern 4a is longer than the other places, and it is not limited to 1/2 or less of the effective wavelength, but this place is not limited. Then, since the via hole row 60 is interrupted, it is assumed that these via holes 6 do not correspond to “the via holes 6 arranged adjacent to each other in the via hole row 60”.

FIG. 2 shows a plan view of the structure of the millimeter wave semiconductor device 3. However, it is a plan view of the lower surface seen through from above rather than from below. The bump electrode 10 made of gold is formed on the bonding pad 9 on the circuit formation surface. In the example shown in FIG. 2, the circuit of the millimeter-wave semiconductor element 3 is a combination of a so-called through transmission line 11 and an input / output terminal 12, but a filter, a radiating element, an element having various gains, It may be a composite circuit thereof.

FIG. 3 is a cross-sectional view taken along the line I--I of the dielectric circuit board 2 (see FIG. 1) in which the millimeter wave semiconductor element 3 (see FIG. 2) is thermocompression bonded by the flip chip bonding method. Show. A back surface ground potential pattern 5 is formed on the entire surface of the dielectric circuit board 2 opposite to the main surface. The ground potential pattern 4b and the back surface ground potential pattern 5 are electrically connected by a via hole 6 filled with a tungsten paste as a conductor. Since the via holes 6 are arranged not on a straight line as described above, in FIG.
The cross-sectional shape of each is different.

(High Frequency Characteristics) FIG. 4 is a schematic diagram showing the high frequency characteristics of the millimeter wave semiconductor device 1 according to the present embodiment. In the millimeter wave semiconductor device 1 according to the present embodiment, as with the conventional millimeter wave semiconductor device 1, there is a tendency that the frequency wave gradually deteriorates as the frequency increases. But,
The appearance of the local deterioration frequency is significantly different from the conventional one. That is, the number of local deterioration frequencies is increased to eight from F6 to F13 as shown in FIG. 4, but the degree of deterioration of each is small. As a result, the number of local deterioration frequencies below the lowest usable level T1 in the used frequency band is one as shown in FIG. 15 in the past, but in the present embodiment, there is one as shown in FIG. do not do.

(Operation / Effect) In the millimeter wave semiconductor device 1 according to the present embodiment, the distance L1 between the via holes 6 arranged adjacent to each other in the via hole array 60.
However, since the distance is less than ½ of the effective wavelength, electromagnetic isolation between the portion surrounded by the via hole 6 and the outside thereof is effectively performed.

Millimeter-wave semiconductor device 1 according to the present embodiment
In the above, since the arrangement of the via holes 6 is not on a straight line on each side as described above, the positional relationship between the via holes 6 is confused and diversified. Therefore, the resonance frequency is different for each part. Although the probability of resonance increases and the number of local deterioration frequencies tends to increase by having different resonance frequencies for each part, it is unlikely that the conventional via holes 6 are arranged at regular intervals in the millimeter wave semiconductor device 1. In addition, the phenomenon that many other parts resonate in response to the resonance of a certain frequency, and are amplified and propagated is unlikely to occur. As a result, the degree of deterioration at each local deterioration frequency becomes small, and it does not fall below the lowest usable level T1 within the used frequency band.

In the present embodiment, the via holes 6 are not arranged in a straight line on each side. However, even if the via holes 6 are linear on each side, they are arranged at unequal intervals. , The same effect can be obtained.

It should be noted that the via hole train 60 may be used in combination with other means for electromagnetically shielding to realize electromagnetic shielding, but the via hole train 60 is substantially closed. By arranging so as to form a region, the via hole row 60 itself can almost completely electromagnetically shield the inside and the outside of the region.

(Embodiment 2) (Structure) FIG. 5 is a plan view of the dielectric circuit board 2. The distance L2 between the via holes 6 arranged adjacent to each other in the via hole array 60 is 3/8 or less of the effective wavelength. Dielectric circuit board 2 and millimeter wave semiconductor device 1
The other parts of the configuration are the same as those in the first embodiment.

(Operation / Effect) The distance L2 between the via holes 6 arranged adjacent to each other in the via hole array 60.
However, since the distance is equal to or shorter than 3/8 of the effective wavelength, electromagnetic isolation between the portion surrounded by the via hole 6 and the outside thereof is further strengthened and effectively performed.

Although the distance L2 was examined for other values, it was found that a particularly effective effect was obtained when the distance L2 was 3/8 or less.

According to the present embodiment, even when it is necessary to use the millimeter wave semiconductor element 3 which generates a strong electromagnetic field,
Sufficiently electromagnetically shielded.

(Third Embodiment) Furthermore, from the result of a series of examinations in the present invention, the arrangement for adding randomness to the positional relationship between the via holes 6 is not limited to the examples of the first and second embodiments, and geometrical It became clear that there are several factors. That is, an effective structure has been clarified for via holes which are relatively close to each other and for shapes formed by some via holes.

(Structure) FIG. 6 schematically shows a part of the via hole array 60 of the dielectric circuit board 2 in the present embodiment. The via holes 6 (6a to 6e) are arranged so as not to be aligned, but one arbitrary via hole 6
From the two via holes 6 adjacent to each other, the distance to one of the two via holes 6 is different from the distance to the other.

For example, focusing on the via hole 6c,
The distance to the via hole 6b is L3.
The distance to d is L4, both L3 and L4 are less than 1/2 of the effective wavelength, and L3 and L4 are different distances.

The structures of the other parts of the dielectric circuit board 2 and the millimeter wave semiconductor device 1 are the same as those in the first embodiment.

(Operation / Effect) Since the distance between the via holes 6b and 6c is different from that between the via holes 6c and 6d,
There is a high probability that the resonance frequency between the via holes 6b and 6c and the resonance frequency between the via holes 6c and 6d are different, so that amplification and propagation are easily suppressed.
This is not limited to between two adjacent via holes 6, and the same applies to two via holes 6 separated by one, two or more via holes 6. However, practically, if the condition that the distance from one via hole 6 to one of the two via holes 6 adjacent to both sides of the via hole 6 and the distance to the other is different is arranged to be an arbitrary via hole 6, The degree of occurrence of resonance can be suppressed sufficiently small.

(Fourth Embodiment) (Structure) FIG. 7 schematically shows a part of the via hole array 60 of the dielectric circuit board 2 in the present embodiment. The via holes 6 (6f to 6s) are arranged so as not to be aligned. For convenience of description, one via hole 6 arbitrarily selected from these via holes 6 is referred to as a “central via hole”, and an effective wavelength of 1 from the central via hole.
Within the range of the distance of / 2 or less, the number of other via holes 6 which are substantially equal to each other from the central via hole is arranged to be 3 or less.

For example, paying attention to the via hole 6l, and considering it as the central via hole, the via holes 6g to 6s (6l) existing inside the circle having the radius R1 corresponding to 1/2 of the effective wavelength as the center with the center of the via hole 6l as the center. , Except that) becomes a problem. Each via hole 6g-6s
Considering each distance from (excluding 6l) to the via hole 6l, as a combination in which the distances are substantially equal to each other, for example, the via holes 6s and 6r have the same distance R1 and the via holes 6i, 6o and 6p are the same. Are equal in distance R2. There is no other example in which four or more via holes 6 are arranged at the same distance. Therefore, within the range of the distance from the via hole 6l, which is the central via hole, to 1/2 or less of the effective wavelength, the maximum value of the number of other via holes 6 that are substantially equal to each other from the central via hole is the via holes 6i, 6o at the distance R2. , 6
It is the number of p, that is, 3.

The structures of the other parts of the dielectric circuit board 2 and the millimeter wave semiconductor device 1 are the same as those in the first embodiment.

(Function / Effect) From a certain central via hole,
The condition that the number of other via holes 6 at substantially equal distances is 3 or less is established regardless of which via hole 6 is the central via hole, and amplification and propagation of resonance due to the distance can be suppressed.

It should be noted that the occurrence of resonance can be reduced by reducing the maximum value such as "2 or less" or "1 or less" instead of "3 or less" under the conditions of the present invention. However, practically, if it is 3 or less, the degree of occurrence of resonance can be suppressed sufficiently small.

Also, the effect of suppressing the occurrence of resonance by reducing the number of other via holes that are substantially equidistant from the central via hole is reduced when the distance of the central via hole is too long. Therefore, practically, it is sufficient to consider the radius from the central via hole to be within a range of 1/2 or less of the effective wavelength.

(Fifth Embodiment) (Structure) FIG. 8 schematically shows a part of a via hole array 60 of a dielectric circuit board 2 according to the present embodiment. The via holes 6 (6t to 6z) are arranged so as not to be on a straight line, but from the midpoint of a line segment formed by connecting the centers of two arbitrarily selected via holes 6 adjacent to each other,
Within the range of a distance of 1/2 or less of the effective wavelength, the number of other via holes 6 intersecting a straight line formed by extending this line segment is 2 or less.

For example, paying attention to the via holes 6v and 6w as two arbitrarily selected adjacent via holes 6, the effective wavelength is 1 with the midpoint of the line segment connecting the centers of the via holes 6v and 6w as the center. Via holes 6t existing inside a circle having a radius R3 corresponding to 1/2
6y (excluding 6v and 6w) becomes a problem. this house,
There are two via holes 6t and 6y as other via holes 6 that intersect a straight line III-III formed by extending a line segment that connects the centers of the via holes 6v and 6w.

The structures of the other parts of the dielectric circuit board 2 and the millimeter wave semiconductor device 1 are the same as those in the first embodiment.

(Operation / Effect) At frequencies in the millimeter wave band, the propagation of resonance tends to proceed straight. Therefore, the resonance related to the via holes 6v and 6w is the via holes 6v and 6w.
Propagation can be suppressed by reducing the arrangement of the other via holes 6 on the straight line III-III passing through the centers of.

The smaller the number of other via holes 6 arranged on the straight line III-III, and the more the compliance with this condition over a wide range, the more effective the propagation is suppressed. However, practically, for two arbitrarily selected via holes 6 adjacent to each other, from the midpoint of the line segment connecting the centers of these via holes 6 to 1/2 of the effective wavelength.
If the number of other via holes 6 intersecting with a straight line formed by extending this line segment is set to 2 or less within the following distance range, the degree of resonance can be sufficiently suppressed.

(Sixth Embodiment) (Structure) FIG. 9 is a plan view showing a dielectric circuit board 2 in the present embodiment. However, in FIG. 9, the dielectric portion 20 of the dielectric circuit board 2 is omitted. The via holes 6 forming the via hole row 60 are arranged so as not to be aligned on each side.
Includes a substantially arc-shaped portion 13 composed of four or more via holes 6 arranged in a substantially arc shape. Furthermore, the major axis of the arc of each substantially arc-shaped portion 13 is less than 1/2 of the effective wavelength. For example, in FIG. 9, the major axis R4 is less than 1/2 of the effective wavelength.

The structures of the other parts of the dielectric circuit board 2 and the millimeter wave semiconductor device 1 are the same as those in the first embodiment.

(Operation / Effect) Since the major axis of the arc of each substantially arc-shaped portion 13 is less than 1/2 of the effective wavelength, the frequency of resonance generated in each substantially arc-shaped portion 13 can be made relatively high. it can. Therefore, even if the high frequency characteristic is deteriorated by resonance, the resonance frequency is F shown in FIG.
The frequency may be higher than 2, and it is possible to avoid falling below the usable level in the used frequency band.

(Embodiment 7) (Structure) FIG. 10 is a plan view showing a dielectric circuit board 2 in the present embodiment. However, in FIG. 10, the dielectric portion 20 of the dielectric circuit board 2 is omitted. The via holes 6 forming the via hole row 60 are arranged so as not to be aligned on each side, and the via hole row 60 includes a substantially rectangular portion 14 composed of four or more via holes 6 arranged in a substantially rectangular shape. There is. Furthermore, the length of the rectangular long side of each substantially rectangular portion 14 is less than 1/2 of the effective wavelength. For example, in FIG. 10, the major axis R5 is less than 1/2 of the effective wavelength.

The structures of the other parts of the dielectric circuit board 2 and the millimeter wave semiconductor device 1 are the same as those in the first embodiment.

(Operation / Effect) Since the length of the rectangular long side of each substantially rectangular portion 14 is less than 1/2 of the effective wavelength,
The frequency of resonance generated in each substantially rectangular portion 14 can be relatively increased. Therefore, even if the high-frequency characteristics deteriorate due to resonance, the resonance frequency can be set to a frequency higher than F2 shown in FIG. 4, and it can be avoided that the resonance frequency falls below the usable level in the use frequency band.

(Embodiment 8) (Structure) FIG. 11 schematically shows a part of the parallel via hole array 62 included in the dielectric circuit board 2 according to the present embodiment. The “parallel via hole array 62” is an array of via holes 60 arranged along a plurality of substantially parallel straight lines. In the parallel via hole array 62 according to the present embodiment, the via holes 6 are arrayed along the straight line at unequal intervals.

The structures of the other parts of the dielectric circuit board 2 and the millimeter wave semiconductor device 1 are the same as those in the first embodiment.

(Operation / Effect) With this arrangement, the resonance frequency can be made relatively high. Therefore, even if the high-frequency characteristics deteriorate due to resonance, the resonance frequency can be set to a frequency higher than F2 shown in FIG. 4, and it can be avoided that the resonance frequency falls below the usable level in the use frequency band.

It should be noted that the above-described embodiment disclosed this time is illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description but by the scope of the claims, and includes meaning equivalent to the scope of the claims and all modifications within the scope.

[0074]

According to the dielectric circuit board of the present invention,
Since the via holes arranged to shield electromagnetic waves are arranged so that they do not lie on a straight line on each side or are arranged at unequal intervals, randomness is added to the positional relationship between the via holes and diversified, The resonance frequency is different for each part. As a result, the phenomenon that many other parts resonate in response to the resonance of a certain frequency, and are amplified and propagated is unlikely to occur. Further, by setting the distance between the via holes arranged adjacent to each other to be less than 1/2 of the effective wavelength, preferably 3/8 or less, the electromagnetic wave between the portion surrounded by the via holes and the outside thereof is reduced. Blocking is further strengthened and effectively performed.

Further, since the via hole array includes the substantially arcuate portion and the substantially rectangular portion, the resonance frequency can be relatively increased, and as a result, the high frequency characteristic is lower than the usable level in the usable frequency band. Can be avoided.

[Brief description of drawings]

FIG. 1 is a plan view of a dielectric circuit board according to a first embodiment of the present invention.

FIG. 2 is a plan view of the structure of the millimeter-wave semiconductor device according to the first embodiment of the present invention seen through from above.

FIG. 3 is a cross-sectional view of the millimeter wave semiconductor device according to the first embodiment of the present invention taken along the line I-I of FIGS. 1 and 2.

FIG. 4 is a schematic diagram showing a high frequency characteristic of the millimeter wave semiconductor device according to the first embodiment of the present invention.

FIG. 5 is a plan view of a dielectric circuit board according to a second embodiment of the present invention.

FIG. 6 is a schematic view of a part of a via hole row of a dielectric circuit board according to a third embodiment of the present invention.

FIG. 7 is a schematic view of a part of a via hole row of a dielectric circuit board according to a fourth embodiment of the present invention.

FIG. 8 is a schematic view of a part of a via hole row of a dielectric circuit board according to a fifth embodiment of the present invention.

FIG. 9 is a plan view of a dielectric circuit board according to a sixth embodiment of the present invention.

FIG. 10 is a plan view of a dielectric circuit board according to a seventh embodiment of the present invention.

FIG. 11 is a schematic diagram of a part of a parallel via hole array of a dielectric circuit board according to an eighth embodiment of the present invention.

FIG. 12 is a plan view of a dielectric circuit board based on a conventional technique.

FIG. 13 is a plan view showing a millimeter wave semiconductor device according to a conventional technique.

FIG. 14 is a cross-sectional view taken along the line II-II of FIGS. 12 and 13 showing a millimeter wave semiconductor device based on a conventional technique.

FIG. 15 is a schematic diagram showing an example of high-frequency characteristics of a millimeter-wave semiconductor device based on a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 millimeter wave semiconductor device, 2 dielectric circuit board, 3 millimeter wave semiconductor element, 4 millimeter wave semiconductor element mounting circuit pattern, 4a signal input / output pattern, 4b ground potential pattern, 5 back surface ground potential pattern, 6, 6a, 6b , 6
c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6
k, 6l, 6m, 6n, 6o, 6p, 6q, 6r, 6
s, 6t, 6u, 6v, 6w, 6x, 6y, 6z via hole, 7 millimeter wave semiconductor element mounting part, 9 bonding pad, 10 bump electrode, 11 transmission line, 12 input / output terminal, 13 approximately arc-shaped part, 14 approximately quadrangle Shape part, 2
0 dielectric part, 60 via hole row, 62 parallel via hole array.

Claims (11)

(57) [Claims] 1. A formable dielectric circuit board millimeter wave semiconductor device by implementing a millimeter-wave semiconductor device, a via hole rows arranged in correspondence with the respective sides of the mounting region of the millimeter wave semiconductor devices The dielectric circuit board, wherein the via hole array is such that via holes including a grounded conductor therein are arranged so as not to be aligned. 2. A formable dielectric circuit board millimeter wave semiconductor device by implementing a millimeter-wave semiconductor device, a via hole rows arranged in correspondence with the respective sides of the mounting region of the millimeter wave semiconductor devices The dielectric circuit board is characterized in that the via hole array is such that via holes including a grounded conductor therein are arranged such that a distance between adjacent via holes is not constant. 3. The dielectric circuit board according to claim 1, wherein the distance between any two via holes arranged adjacent to each other is less than 1/2 of the effective wavelength on the substrate surface. 4. The arrangement according to claim 1, wherein the distance from any one of the via holes to one of the two adjacent via holes on both sides of the via hole is different from the distance to the other. The dielectric circuit board according to any one of the claims. 5. The distance from the central via hole is substantially equal to each other within a distance of 1/2 or less of an effective wavelength on the substrate surface from a central via hole which is one via hole arbitrarily selected from the via holes. The dielectric circuit board according to claim 1, wherein the number of other via holes is 3 or less. 6. A range of a distance of 1/2 or less of an effective wavelength on a substrate surface from a midpoint of a line segment formed by connecting centers of two adjacent via holes arbitrarily selected from the via holes. The number of other via holes that intersect the straight line formed by extending the line segment is 2
The dielectric circuit board according to any one of claims 1 to 5, which is as follows. 7. A formable dielectric circuit board millimeter wave semiconductor device by implementing a millimeter wave semiconductor devices, has a via hole column that is sequence, the via hole row,
Via holes including a grounded conductor inside are arranged, the via hole row includes a substantially arc-shaped portion composed of four or more via holes arranged in a substantially arc shape, and a major axis of an arc of each of the substantially arc-shaped portions is 1 / effective wavelength on the substrate surface
A dielectric circuit board that is less than 2. 8. A formable dielectric circuit board millimeter wave semiconductor device by implementing a millimeter wave semiconductor devices, has a via hole column that is sequence, the via hole row,
Via holes including a grounded conductor inside are arranged, and the via hole row includes a substantially rectangular portion composed of four or more via holes arranged in a substantially rectangular shape, and a rectangular length of each rectangular portion. A dielectric circuit board having a side length of less than half the effective wavelength on the surface of the board. 9. The via hole row includes a parallel via hole array along a plurality of substantially parallel straight lines, and the via holes arranged along each straight line of the parallel via hole array are arranged at unequal intervals. The dielectric circuit board according to claim 1. 10. A millimeter wave semiconductor device including the dielectric circuit board according to claim 1, which is mounted with a millimeter wave semiconductor element. 11. A millimeter wave semiconductor device in which a millimeter wave semiconductor element whose outer edge portion is surrounded by a row of projecting electrodes including a plurality of projecting electrodes arranged in a straight line is mounted on a dielectric circuit board. The body circuit board has a row of via holes in the vicinity of each of the protruding electrode rows, and the via hole row includes a via hole containing a grounded conductor inside thereof in parallel with the corresponding protruding electrode row. Millimeter-wave semiconductor devices are arranged so that they do not lie on a straight line.