This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2012-041830, filed Feb. 28, 2012, the entire contents of which are incorporated herein by reference.
Embodiments described herein relate generally to semiconductor packages.
In the field of semiconductor devices for use in, for example, portable communication apparatuses represented by a mobile phone, there is a demand for suppression of leakage of unnecessary radio waves to the outside of the apparatuses, in order to suppress adverse influence of the waves on the communication characteristics. To satisfy the demand, semiconductor packages having a shielding function have been developed. As the semiconductor packages having the shielding function, those of a structure, in which a shielding layer is provided along the outer surface of a sealing resin layer that seals a semiconductor chip mounted on an interposer substrate, are known.
However, when the semiconductor package is aimed to perform wireless communication with external devices, even the radio waves used for the communication will be shielded, which makes the communication difficult. As a conventional structure developed in view of this, utilizing the fact that the frequency of the unnecessary radio waves is sufficiently lower than that of radio waves used for communication, a structure is known, in which an opening is formed in the shield layer provided on the upper surface of a semiconductor package.
In the conventional structure, however, the distance between the opening for radiating radio waves for communication and a semiconductor chip is short, which reduces the unnecessary radio wave shielding performance. The opening, which is formed in the upper surface of the semiconductor package, is also disadvantageous because lateral communication is hard to perform.
Semiconductor packages, an information processing apparatus and a storage device, according to embodiments, will be described in detail with reference to the accompanying drawings. In the embodiment, like reference numbers denote like elements, and no duplicate explanation will be given. Further, although in the embodiments, a transmission operation is described, a receiving operation can also be performed.
In general, according to the embodiments, a semiconductor package includes a semiconductor chip, a first conductive layer, a second conductive layer, and a power feeder. The semiconductor chip is provided on a substrate, is sealed with a resin, and contains a transmission/reception circuit. The first conductive layer is grounded and covers a first region on a surface of the resin. The second conductive layer is not grounded and covers a second region on the surface of the resin other than the first region. A power feeder electrically connects the semiconductor chip to the second conductive layer.
A semiconductor package 100 according to a first embodiment will be described referring to
In the semiconductor package 100, a semiconductor chip 101 is mounted on a substrate 102 and sealed by a sealing resin 103 as an insulator. The semiconductor chip 101 contains a transmission/reception circuit for transmitting/receiving signals. The sealing resin 103 is covered with a conductive layer 104 formed of a conductor. The conductive layer 104 is electrically connected to a ground layer (not shown) incorporated in the substrate 102, and is therefore grounded. By thus grounding the conductive layer 104, leakage, to the outside of the package, of unnecessary radio waves mainly generated by the semiconductor chip 101 is suppressed.
However, part of the conductive layer 104 is electrically isolated, and is set as a non-grounded conductive layer 105. The non-grounded conductive layer 105 and the semiconductor chip 101 are electrically connected by a power feeder 106, and realize communication with the outside through the non-grounded conductive layer 105.
By thus covering the sealing resin surface of the semiconductor package with a conductive layer, unnecessary radio wave-shielding performance can be imparted. Further, by thus setting part of the conductive layer as a non-grounded region, the part can be used as an antenna.
Referring then to
By thus connecting the semiconductor chip 101 to an antenna by a power feeding line (such as coplanar line), power loss can be suppressed.
Referring then to
By thus providing an antenna (i.e., the non-grounded conductive layer 105) on the package lateral surface, lateral communication can be realized. Although the antenna may reduce the shielding performance due to its conductive layer, adverse influence by the reduction of the shielding performance can be suppressed, since the antenna is distant from the noise source (in the semiconductor chip).
In
Referring then to
In
Referring now to
Two of the four non-grounded conductive layers 105 are supplied with power as shown in
In the above-described first embodiment, a shielding function for blocking unnecessary electromagnetic waves can be imparted to the semiconductor package by coating the sealing resin surface of the package with a conductive layer.
Further, an antenna can be provided by making part of the conductive layer as a non-grounded region, with the result that antenna radiation can be improved to thereby enable communication with a wireless apparatus located, for example, laterally.
A semiconductor package according to a second embodiment differs from that of the first embodiment in that in the former, the conductive line and the non-grounded conductive layer are connected by capacitive coupling.
Referring to
The second embodiment differs from the first embodiment in the shape of the power feeder 106. Specifically, the conductive line 201 is not physically connected to the non-grounded conductive layer 105, but connected thereto via a space. By virtue of this, it is not necessary to keep physical connection between the conductive line 201 and the non-grounded conductive layer 105, which leads to enhancement in the durability of the semiconductor package. Further, by adjusting the shape of the open end of the conductive line 201 and the distance between the line 201 and the non-grounded conductive layer 105, impedance matching can be easily realized.
Although
As described above, the second embodiment, in which the conductive line and the non-grounded conductive layer are connected by capacitive coupling, can provide such advantages, in addition to the advantages of the first embodiment, that impedance matching can be easily matched, and a larger number of options can be presented for the position of the non-grounded conductive layer 105 than in the first embodiment.
A description will now be given of an information processing apparatus and a storage device according to a third embodiment, which are provided with the semiconductor package of the first or second embodiment.
Referring first to
As shown in
The wireless device 100 transmits and receives data from an external device. The wireless device 100 is formed of, for example, the semiconductor package of the first or second embodiment.
The processor (also called a controller) 901 processes data received from and transmitted to the wireless device 100.
The memory 902 stores data received from and transmitted to the processor 901.
Referring then to
In this embodiment, the wireless machine examples are a note-type personal computer (note PC) 1001 and a mobile terminal 1002. The note PC 1001 and the mobile terminal 1002 comprise displays 1003 and 1004 for displaying still and moving images. Each of the note PC 1001 and the mobile terminal 1002 also comprises a central processing unit (CPU) (also called a controller), a memory, etc. Each of the note PC 1001 and the mobile terminal 1002 further comprises an internal or external wireless device 100, through which data communication is performed using a frequency of, for example, a millimeter waveband. In the third embodiment, the note PC 1001 and the mobile terminal 1002 may incorporate the semiconductor package 100 of the first or second embodiment.
Further, if the non-grounded conductive layers 105 of the wireless devices incorporated in the note PC 1001 and the mobile terminal 1002 are arranged so that their directions, in which high directivity is obtained, are opposed to each other, exchange of data therebetween can be performed with high efficiency.
Although
Referring then to
As shown in
In the above-described third embodiment, by installing the semiconductor package in an information processing apparatus or storage device, such as a note PC, a mobile terminal and a memory card, which perform wireless data communication, data transmission and reception can be performed with high efficiency.
In the embodiments described above, a shielding function for blocking unnecessary electromagnetic waves can be imparted to the semiconductor package by coating the sealing resin surface of the package with a conductive layer, and an antenna can be formed by making part of the conductive layer as a non-grounded region, thereby facilitating communication in an arbitrary direction.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiment described herein may be made without departing from the spirit of the invention. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
Number | Date | Country | Kind |
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2012-041830 | Feb 2012 | JP | national |