JP4490832B2 - Semiconductor package - Google Patents

Description

  The present invention relates to a structure of a semiconductor package.

  FIG. 2 is a cross-sectional view of a conventional semiconductor module configured by covering a semiconductor package base portion on which a semiconductor chip and a dielectric substrate such as alumina or ceramic are mounted with a semiconductor package lid (not related to a known invention) ).

  The dielectric substrate 4, the dielectric substrate 5, and the semiconductor chip 3 are mounted on the semiconductor package base 1, the input terminal 8 and the dielectric substrate 4 are connected, and the dielectric substrate 4 and the semiconductor chip 3 are connected by the bonding wires 6. The semiconductor chip 3 and the dielectric substrate 5 are connected by the bonding wire 7, the dielectric substrate 5 and the output terminal 9 are connected, and the semiconductor package lid 2 is placed on the semiconductor package base 1 to constitute a semiconductor module.

  In this configuration, when the semiconductor chip 3 constitutes an amplifier having a high output and a high gain, the oscillation state is likely to occur. Actually, when the operating frequency band was in the range of 55 GHz to 65 GHz, no signal was input and the transmission state was set.

  In order to prevent this, the position of one radio wave absorber 12 is adjusted to the semiconductor package lid 2 by trial and error, and is attached to the inner side surface of the semiconductor package lid 2 so that the output side of the semiconductor chip 3 is connected to the input side. The oscillation is stopped by attenuating the positive feedback loop of the electromagnetic wave propagating through the space.

  In addition, Patent Literature 1, Patent Literature 2, and the like can be cited as patent literature in which one radio wave absorber is attached to the inner surface of the semiconductor package.

Japanese Patent Laid-Open No. 2004-22685 Japanese Patent Laid-Open No. 2003-31988

  In the configuration of the prior art described above, it is necessary to adjust the position of one radio wave absorber attached to the semiconductor package lid to a position where the positive feedback loop of the electromagnetic wave propagating through the space can be attenuated, It takes time and effort.

  In Patent Document 1 and Patent Document 2 described above, in contrast to the conventional technique described above, since one radio wave absorber is pasted over the entire inner surface of the semiconductor package 2, radio wave absorption The body itself is large and therefore takes time and effort to apply. Patent Document 1 and Patent Document 2 do not mention anything about dividing the positive feedback loop of electromagnetic waves propagating in space.

  An object of the present invention is to provide a semiconductor package in which it is easy to effectively attenuate a positive feedback loop of electromagnetic waves propagating in space from the output side to the input side of a semiconductor chip.

  The present invention relates to a semiconductor package comprising a semiconductor package base on which a semiconductor chip is mounted and a semiconductor package lid that covers the semiconductor package base so as to seal the semiconductor chip, and the semiconductor package lid has a plurality of radio wave absorbers. A semiconductor package characterized in that a piece is affixed.

  According to the present invention, in the semiconductor package described above, the plurality of radio wave absorber pieces are attached to an inner surface of the semiconductor package lid.

  According to the present invention, in the semiconductor package described above, the plurality of radio wave absorber pieces are affixed at an interval of substantially one wavelength in the operating frequency band of the semiconductor chip.

  According to the present invention, it is possible to obtain a semiconductor package in which it is easy to effectively attenuate the positive feedback loop of the electromagnetic wave propagating through the space from the output side to the input side of the semiconductor chip.

  In the best mode for carrying out the invention, a first radio wave absorber is affixed to the inner surface of the semiconductor package lid, just above the front end of the semiconductor chip constituting the amplifier inside the semiconductor package, and the output side Attenuates the positive feedback loop in which the electric field of the electromagnetic wave propagating through the space becomes maximum at the input end of the semiconductor chip constituting the amplifier inside the semiconductor package.

  Furthermore, by attaching a second electromagnetic wave absorber inside a position substantially one wavelength away from the first electromagnetic wave absorber in free space of the oscillation frequency, the inside of the semiconductor package among the electromagnetic waves propagating through the space from the output side Attenuates the positive feedback loop that maximizes the electric field at the input end of the semiconductor chip constituting the amplifier.

  Also, by providing a gap between the first wave absorber and the second wave absorber, the reverse phase-shifting loop where the electric field of the electromagnetic wave becomes strong at a position that is substantially half the wavelength is not attenuated and is input from the output side. The space is propagated to the side, and the positive feedback loop that becomes the oscillation state is divided.

  FIG. 1 is a cross-sectional view of a semiconductor package according to an embodiment of the present invention.

  The dielectric substrate 4, the dielectric substrate 5, and the semiconductor chip 3 are mounted on the semiconductor package base 1, the input terminal 8 and the dielectric substrate 4 are connected, and the dielectric substrate 4 and the semiconductor chip 3 are connected by the bonding wires 6. Semiconductor in which semiconductor chip 3 and dielectric substrate 5 are connected by bonding wire 7, dielectric substrate 5 and output terminal 9 are connected, and first radio wave absorber 10 and second radio wave absorber 11 are attached to the inner side surface. By covering the package lid 2 on the semiconductor package base 1, a semiconductor module is configured.

  In this configuration, when the first radio wave absorber 10 and the second radio wave absorber 11 are not attached to the inner surface, when the semiconductor chip 3 constitutes a high output and high gain amplifier, the oscillation state is established. easy. Actually, when the semiconductor chip 3 with high output and high gain whose operating frequency is in the range of 55 GHz to 65 GHz is used, no oscillation is generated when no signal is input in the operating frequency range of 55 GHz to 65 GHz.

  On the other hand, in the embodiment of the present invention, as shown in FIG. 1, the first radio wave absorber 10 and the second radio wave absorber 11 are attached to the inner surface of the semiconductor package lid 2. The first radio wave absorber 10 has its input side end positioned directly above the tip of the semiconductor chip 3 on the signal input side, and is attached toward the signal output side. The second radio wave absorber 11 has a signal input at a position inside the position where the output side end is separated from the input side end of the first radio wave absorber 10 by substantially one wavelength in the operating frequency band of the semiconductor chip 3. It is stuck to the side.

  In FIG. 1, the interval A is the interval from the input-side tip of the semiconductor chip 3 to the first radio wave absorber 10, the width B is the width of the first radio wave absorber 10, and the interval C is the first radio wave absorber 10. And the width D of the second wave absorber 11 indicates the width of the second wave absorber 12. The interval A is a positive value in the direction of signal flow.

  FIG. 3 is a diagram showing values of the interval A, the width B, the interval C, and the width D of the radio wave absorber that has been stopped in FIG. In FIG. 1, when the first radio wave absorber 10 and the second radio wave absorber 11 are not attached to the inner surface of the semiconductor package lid 2, a high output and high gain with an operating frequency in the range of 55 GHz to 65 GHz. When the semiconductor chip 3 was used, an oscillation state was generated when no signal was input in the above-mentioned operating frequency range of 55 GHz to 65 GHz.

  On the other hand, the first radio wave absorber 10 and the second radio wave absorber 11 are affixed to the inner surface of the semiconductor package lid 2 according to the values of interval A, width B, interval C, and width D shown in FIG. However, the oscillation stopped. Oscillation stopped in any of samples 1, 2, and 3.

  From the interval A in FIG. 3, the first wave absorber 10 has an input side end in a range of −0.16 [mm] to 0.24 [mm] from the signal input side tip of the semiconductor chip 3, That is, it can be said that the semiconductor chip 3 is affixed to the semiconductor package lid 2 so as to be located immediately above the same position as the tip of the signal input side.

  FIG. 4 is a diagram showing a total value of the width B, the interval C, and the width D shown in FIG. One wavelength in the free space of 65 GHz, which is the highest frequency among the above-mentioned operating frequencies of 55 GHz to 65 GHz, can be calculated as 4.6 [mm], but the value in FIG. 4 is from 4.26 [mm] to 4.GHz. Since it is a range of 48 [mm], which is substantially one wavelength, it can be said that the first radio wave absorber 10 and the second radio wave absorber 11 are affixed to the inside of a position at a distance of substantially one wavelength.

  As described above, in the embodiment of the present invention, the first radio wave absorber 10 with the input side end located is pasted substantially directly above the input side tip of the semiconductor chip 3, and in the operating frequency band of the semiconductor chip 3. Since the second radio wave absorber 11 is affixed to the inside of a position that is substantially spaced apart by one wavelength, the affixing positions of the first radio wave absorber 10 and the second radio wave absorber 11 are determined in advance. It is easy to effectively attenuate and divide the positive feedback loop of the electromagnetic wave propagating through the space from the output side to the input side of the semiconductor chip, and to reduce the time and labor required for adjustment to stop the oscillation state it can.

It is sectional drawing of the semiconductor package of embodiment of this invention. It is sectional drawing of the conventional semiconductor package. It is a figure which shows the value of the space | interval A, the width | variety B, the space | interval C, and the width | variety D of the electromagnetic wave absorber which implemented in FIG. It is a figure which shows the value which totaled the width B, the space | interval C, and the width | variety D which were shown in FIG.

Explanation of symbols

  1: semiconductor package base, 2: semiconductor package lid, 3: semiconductor chip, 4: dielectric substrate, 5: dielectric substrate, 6: bonding wire, 7: bonding wire, 8: input terminal, 9: output terminal, 10 : First radio wave absorber, 11: second radio wave absorber, 12: radio wave absorber.

Claims (1)

In a semiconductor package comprising a semiconductor package base on which a semiconductor chip is mounted and a semiconductor package lid that covers the semiconductor package base so as to seal the semiconductor chip, a first radio wave absorber piece and a second second Rutotomoni affixed wave absorber piece, the first wave absorber pieces, the disposed so as to be positioned substantially directly above the signal input side of the semiconductor chip, the second wave absorber piece, The width of the first radio wave absorber piece, the width of the second radio wave absorber piece, and the total distance between them are arranged in a range of one wavelength at the operating frequency of the semiconductor chip, Semiconductor package.

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