Electricity: conductors and insulators – Boxes and housings – Hermetic sealed envelope type
Reexamination Certificate
2003-12-03
2004-09-28
Ngo, Hung V. (Department: 2831)
Electricity: conductors and insulators
Boxes and housings
Hermetic sealed envelope type
C174S050510, C174S050510
Reexamination Certificate
active
06797881
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a cross substrate, a method of mounting a semiconductor element, and a semiconductor device, and in particular to a cross substrate which is a mount substrate to which a semiconductor substrate is mounted, and to a method of mounting a semiconductor element to the cross substrate.
2. Description of the Related Art
In a conventional method of manufacturing a semiconductor device in which a semiconductor element is mounted on a mount substrate, as illustrated in
FIG. 10
, a semiconductor element
82
is disposed on a wiring forming surface
80
a
of a mount substrate
80
such that a circuit forming surface
82
a
of the semiconductor element
82
is the upper surface. After the semiconductor element
82
is fixed by an adhesive to the mount substrate
80
, a substrate side electrode
84
and an element side electrode
86
are bonded by a metal wire
88
such as a gold wire, and the structure is sealed and packaged by a sealing resin
81
which is insulative.
As illustrated in
FIG. 10
, the semiconductor device obtained by this method becomes excessively thick by an amount corresponding to the loop height H of the wire
88
and the thickness L of the sealing resin
81
covering the wire
88
. In order to overcome this problem, various mounting methods have been proposed.
In one such method, as illustrated in
FIG. 11
, with the circuit forming surface
82
a
of the semiconductor element
82
and the wiring forming surface
80
a
of the mount substrate
80
opposing one another, the substrate side electrodes of the mount substrate
80
and the element side electrodes of the semiconductor element
82
are joined together by solder bumps
85
. The space between the circuit forming surface
82
a
of the semiconductor element
82
and the wiring forming surface
80
a
of the mount substrate
80
is sealed by the sealing resin
81
which is insulative. As shown in
FIG. 11
, because no wire is used in a semiconductor device obtained by this method, a semiconductor device having a thinner package can be obtained.
In recent years, the demand to shrink products equipped with semiconductor devices has increased even more. However, there are limits to shrinking the dimensions of semiconductor devices. Further, because there are limits to shrinking the mounted volume of semiconductor devices, conventional methods cannot completely satisfy this demand.
Namely, in the case of the structure of the conventional semiconductor device illustrated in FIG.
10
and described above, if the entire length of the wire is increased to a certain extent, there are problems such as the wire may contact the corner portion of the semiconductor element and form a short circuit, or the wire may break resulting in a defective connection, or in the worst case, the wire may be disconnected. Because the length of the wire must be extended to a certain extent, the resin sealing the wire becomes thicker than the wiring substrate, and the semiconductor device package becomes that much thicker. Thus, there are limits to shrinking the overall dimensions of the semiconductor device. Further, load may be applied to the wire during the sealing by the sealing resin, or the wire may contact an adjacent wire and form a short circuit, and there is thus the concern that the wire may be broken.
In the case of the structure illustrated in
FIG. 11
, because no wires are used, the problems associated with wires can be avoided, and the semiconductor device on the whole can be made thinner than the semiconductor device illustrated in FIG.
10
. However, because the solder bumps are provided between the mount substrate and the semiconductor element, the semiconductor device becomes excessively thick by an amount corresponding to the height of the solder bumps.
SUMMARY OF THE INVENTION
In view of the aforementioned, an object of the present invention is to provide a cross substrate on which semiconductor elements can be mounted at a high density, a method of mounting a semiconductor element, and a semiconductor device.
The first aspect of the present invention is a cross substrate including at least one resin sealed layer of a cross member, the at least one resin sealed layer of a cross member having warp threads and weft threads, wherein a portion of at least one of the warp threads and weft threads include a plurality of conductive thread-like wire members disposed substantially parallel to one another, with the wire members electrically insulated from one another, and an electrode portion formed at one region of the thread-like wire members.
In the first aspect of the present invention, the cross member forms a wiring portion of the cross substrate at which a semiconductor element is mounted. In order to electrically connect the semiconductor element and the wires, the electrode portions of the semiconductor element are electrically connected to at least one portion of the thread-like wire members which are the wires. Thus, the position at which the semiconductor element is mounted is not limited by the positions at which the electrode portions of the cross member are formed, and the semiconductor element can be mounted relatively freely. Accordingly, semiconductor elements can be mounted at a high density, and the obtained product has a more compact structure than conventional products.
If the thread-like wire members are used, there is no need to provide the electrodes of the semiconductor element at the periphery as in the case of conventional wire bonding. The positions of the electrodes provided at the semiconductor element can be determined freely. Therefore, the number of degrees of freedom in the arranging and designing of the circuit formed on the semiconductor element increases, and the region for the circuit of the semiconductor element can be utilized effectively. Therefore, the semiconductor element is more compact than conventional semiconductor elements, and as a result, the product can be made more compact.
The cross substrate is used not only for the mounting of a semiconductor element to a structure in which a cross member is sealed by sealing resin in advance, but also can be used when the semiconductor element is sealed and mounted at the time the cross members is sealed by sealing resin, as will be explained later.
Namely, the tenth aspect of the present invention is one method of mounting a semiconductor element in which a semiconductor element is mounted to the cross substrate of the first aspect. This method includes the steps of: (a) providing a cross member having at least one layer of warp threads and weft threads, wherein a portion of at least one of the warp threads and weft threads include a plurality of conductive thread-like wire members disposed substantially parallel to one another, with the wire members electrically insulated from one another, and an electrode portion formed at one region of the thread-like wire members; (b) mounting a semiconductor element having an electrode forming surface with a plurality of electrodes thereat, onto the at least one layer of the cross member such that at least one of the plurality of electrodes of the semiconductor element is electrically connected to at least one of the thread-like wires; and (c) sealing the cross member and the electrode forming surface of the semiconductor element with an insulating resin.
As in a second aspect and an eleventh aspect of the present invention, it is preferable that the thread-like wire members have surfaces covered by an insulating material, other than at the electrode portion. In this way, the occurrence of short circuits and the like can be suppressed.
As in a third aspect and a twelfth aspect of the present invention, thread-like wire members can be provided in plural directions by the following structure: the cross substrate further comprises at least one other layer of a cross member, the at least one other cross member having warp threads and weft threads, wherein a portion of at least one of the warp threads and weft threads incl
Ngo Hung V.
Oki Electric Industry Co. Ltd.
Volentine & Francos, PLLC
LandOfFree
Cross substrate, method of mounting semiconductor element,... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cross substrate, method of mounting semiconductor element,..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cross substrate, method of mounting semiconductor element,... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3211584