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Claims  |
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What is claimed is:
1. A multi-chip semiconductor device with reinforcement and chip parts
comprising a plurality of semiconductor device layers which are stacked,
wherein each of said semiconductor device layers has a tape carrier type
semiconductor module and a frame having electrodes on the both side
thereof and having at least one first hole or depression in which said
tape carrier type semiconductor module is mounted, said electrodes and
said tape carrier type semiconductor module being electrically connected,
said frame further having at least one second hole or depression in which
said chip parts are mounted, said chip parts being comprised of at least
one of a capacitor and resistor, and wherein each of said semiconductor
device layers has through holes for connecting said electrodes of
respective ones of said semiconductor device layers, said electrodes
having the same function with respect to each said tape carrier type
semiconductor module.
2. A multi-chip semiconductor device according to claim 2, wherein said
frame has a structure comprised of a plurality of circuit layers which are
stacked and wherein said circuit layers are electrically connected with
each other through conductor portions to form an electric circuit with
said tape carrier type semiconductor module and said chip parts comprised
of at least one of a capacitor and resistor.
3. A multi-chip semiconductor device according to claim 1, wherein the
types of LSI chips mounted on said semiconductor device layers are of the
same type.
4. A multi-chip semiconductor device according to claim 1, wherein LSI
chips mounted on said semiconductor device layers are of at least two
different types.
5. A multi-chip semiconductor device according to claim 1, wherein at least
one wiring pattern comprised of a thin metal layer on said frames is
enlarged in area with no relation to an electric circuit to improve a heat
release efficiency of said semiconductor module.
6. A multi-chip semiconductor device according to claim 1, wherein said
chip parts mounted in said second holes or on electrodes at said second
depression on said frames are chip capacitors which serve for improving
electric properties at high speed operation of LSIs on said tape carrier
type semiconductor modules connected electrically to said frames.
7. A multi-chip semiconductor device according to claim 1, wherein each of
said frames is comprised of glass-epoxy.
8. A multi-chip semiconductor device according to claim 2, wherein the
types of LSI chips mounted on said semiconductor device layers are of the
same type.
9. A multi-chip semiconductor device according to claim 2, wherein LSI
chips mounted on said semiconductor device layers are of at least two
different types.
10. A multi-chip semiconductor device according to claim 2, wherein at
least one wiring pattern comprised of a thin metal layer on said frames is
enlarged in area no relation to an electric circuit to improve a heat
release efficiency of said semiconductor device.
11. A multi-chip semiconductor device according to claim 2, wherein said
chip parts mounted in said second holes or on depression-shaped electrodes
on said frames are chip capacitors which serve for improving electric
properties at high speed operation of LSIs on said tape carrier type
semiconductor modules connected electrically to said frames.
12. A multi-chip semiconductor device with reinforcement, comprising
frames, flexible circuit layers, chip parts and tape carrier type
semiconductor modules, wherein said semiconductor device is comprised of a
plurality of semiconductor device layers which are stacked and each of
which has a frame having conductive electrodes on both sides thereof, said
frame having at least one hole or depression, and a thin flexible circuit
layer having a specified circuit on a surface thereof, said thin flexible
circuit layer being connected electrically to one surface of said frame,
wherein at least one of said chip parts comprised of at least one of a
capacitor and a resistor is mounted in said at least one hole or
depression on said frame or is mounted on said flexible circuit layer in
each of said semiconductor device layers, wherein each of said tape
carrier type semiconductor modules is mounted on and connected
electrically to a surface of said frame on a side thereof opposite to the
side which said flexible circuit layer is connected, and wherein each of
said semiconductor device layers has through-holes for connecting said
electrodes of respective ones of said semiconductor device layers, said
electrodes having the same function with respect to each of said tape
carrier type semiconductor modules.
13. A multi-chip semiconductor device according to claim 12, wherein said
frame has a structure comprised of a plurality of circuit layers which are
stacked and wherein said circuit layers are electrically connected with
each other through conductor portions to form an electric circuit with
said flexible circuit layer.
14. A multi-chip semiconductor device according to claim 12, wherein the
types of LSI chips mounted on said semiconductor device layers are of the
same type.
15. A multi-chip semiconductor device according to claim 12, wherein LSI
chips mounted on said semiconductor device layers are of at least two
different types.
16. A multi-chip semiconductor device according to claim 12, wherein at
least one wiring pattern comprised of a thin metal layer on each of said
frames is enlarged in area with no relation to an electric circuit to
improve a heat release efficiency of said semiconductor device.
17. A multi-chip semiconductor device according to claim 12, wherein at
least one metal foil pattern for heat release is provided on said flexible
circuit layers, said metal foil pattern being enlarged in area with no
relation to an electric circuit to improve a heat release efficiency of
said semiconductor device.
18. A multi-chip semiconductor device according to claim 12, wherein said
chip parts are mounted in said holes or on depression-shaped electrodes on
said frames are chip capacitors which serve for improving electric
properties at high speed operation of LSIs on said tape carrier type
semiconductor modules connected electrically to said frames.
19. A multi-chip semiconductor device according to claim 12, wherein said
semiconductor device layers are stacked so that said flexible circuit
layer of each of said semiconductor device layers is located between a
lower surface of the frame of said semiconductor device layer which said
flexible circuit layer is a part of and an upper surface of the frame of
said semiconductor device layer which is below the semiconductor device
layer which said flexible circuit layer is a part of.
20. A multi-chip semiconductor device according to claim 12, wherein each
of said frames is comprised of glass-epoxy.
21. A multi-chip semiconductor device according to claim 12, wherein each
of said semiconductor device layers is formed so that an upper surface of
the frame of the semiconductor device layer has an opening, wherein said
flexible circuit layer of said semiconductor device layer is mounted on
the bottom surface of the frame and forms a bottom for the opening, and
wherein the tape carrier type semiconductor module of the semiconductor
device layer is located within the opening, with lead electrodes of said
tape carrier type semiconductor module being connected to the upper
surface of the frame.
22. A multi-chip semiconductor device according to claim 13, wherein at
least one metal foil pattern for heat release is provided on said flexible
circuit layers, said metal foil pattern being enlarged in area with no
relation to an electric circuit to improve a heat release efficiency of
said semiconductor module.
23. A multi-chip semiconductor device according to claim 13, wherein at
least one thin metal layer on said frames and at least one metal layer on
said flexible circuit layers there are provided patterns for heat release
enlarging the area of said patterns with no relation to an electric
circuit to improve a heat release efficiency of said semiconductor module.
24. A multi-chip semiconductor device according to claim 13, wherein said
chip parts mounted on said flexible circuit layers are chip capacitors
which serve for improving electric properties at high speed operation of
LSIs on said tape carrier type semiconductor modules connected
electrically to said frames.
25. A multi-chip semiconductor device according to claim 13, wherein said
chip parts are mounted on flexible circuit layers other than said flexible
circuit layers formed on said frames.
26. A multi-chip semiconductor device according to claim 19, wherein each
of said frames is comprised of glass-epoxy.
27. A circuit substrate comprising at least one multi-chip semiconductor
device located on a first main surface of said substrate, wherein said
multi-chip semiconductor device comprises a plurality of semiconductor
device layers which are stacked, wherein each of said semiconductor device
layers has a tape carrier type semiconductor module and a frame having
electrodes on the both sides thereof and having at least one first hole or
depression in which said tape carrier type semiconductor module is
mounted, said electrodes and said tape carrier type semiconductor module
being electrically connected, said frame further having at least one
second hole or depression in which said chip parts are mounted, said chip
parts being comprised of at least one of a capacitor and resistor, and
wherein each of said semiconductor device layers has through holes for
connecting said electrodes of respective ones of said semiconductor device
layers, said electrodes having the same function with respect to each said
tape carrier type semiconductor module.
28. A circuit substrate comprising at least one multi-chip semiconductor
device located on a first main surface of said substrate, wherein said
multi-chip semiconductor device comprises frames, flexible circuit layers,
chip parts and tape carrier type semiconductor modules, wherein said
semiconductor device is comprised of a plurality of semiconductor device
layers which are stacked and each of which has a frame having conductive
electrodes on both sides thereof, said frame having at least one hole or
depression, and a thin flexible circuit layer having a specified circuit
on a surface thereof, said thin flexible circuit layer being connected
electrically to one surface of said frame, wherein at least one of said
chip parts comprised of at least one of a capacitor and a resistor is
mounted in said at least one hole or depression on said frame or is
mounted on said flexible circuit layer in each of said semiconductor
device layers, wherein each of said tape carrier type semiconductor
modules is mounted on and connected electrically to a surface of said
frame on a side thereof opposite to the side which said flexible circuit
layer is connected, and wherein each of said semiconductor device layers
has through-holes for connecting said electrodes of respective ones of
said semiconductor device layers, said electrodes having the same function
with respect to each of said tape carrier type semiconductor modules.
29. A stacked semiconductor device comprising a plurality of semiconductor
device layers stacked on one another, wherein each of said semiconductor
device layers comprises:
a frame having an upper surface and a lower surface, wherein said frame has
electrodes on said upper surface and said lower surface, and further
wherein said frame has a first opening extending from the upper surface to
the lower surface;
a flexible circuit layer having a predetermined circuit formed on a surface
thereof, wherein said flexible circuit layer is mounted on said lower
surface of said frame to form a bottom for the first opening of said
frame; and
a tape carrier type semiconductor module located in said first opening, and
including lead electrodes extending from said tape carrier type
semiconductor module and connected to electrodes on said upper surface of
said frame,
wherein said frame further includes a second opening in said upper surface
of the frame, and wherein a chip part selected from a group consisting of
a capacitor and a resistor is located within said second opening.
30. A stacked semiconductor device according to claim 29, wherein each of
said semiconductor device layers further includes through-holes extending
through said frames for connecting electrodes of respective ones of said
semiconductor device layers to one another.
31. A stacked semiconductor device according to claim 29, wherein each of
said frames is comprised of glass-epoxy.
32. A stacked semiconductor device comprising a plurality of semiconductor
device layers stacked on one another, wherein each of said semiconductor
device layers comprises:
a frame having an upper surface and a lower surface, wherein said frame has
electrodes on said upper surface and said lower surface, and further
wherein said frame has a first opening extending from the upper surface to
the lower surface;
a flexible circuit layer having a predetermined circuit formed on a surface
thereof, wherein said flexible circuit layer is mounted on said lower
surface of said frame to form a bottom for the first opening of said
frame; and
a tape carrier type semiconductor module located in said first opening, and
including lead electrodes extending from said tape carrier type
semiconductor module and connected to electrodes on said upper surface of
said frame,
wherein said semiconductor device layer further comprises a chip part
selected from a group consisting of a capacitor and a resistor, wherein
said chip part is mounted on said flexible circuit layer.
33. A stacked semiconductor device according to claim 32, wherein each of
said semiconductor device layers further includes through-holes extending
through said frames for connecting electrodes of respective ones of said
semiconductor device layers to one another.
34. A stacked semiconductor device according to claim 32, wherein each of
said frames is comprised of glass-epoxy. |
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Claims |
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Description |
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BACKGROUND OF THE INVENTION
The present invention relates to electronic apparatuses which are mounted
with many LSI parts and required to be miniaturized, and, more
particularly, to a hyperfunctioned semiconductor device which can be made
extremely dense.
A semiconductor device wherein a plurality of tape carrier type
semiconductor modules which are connected electrically to frames are
prepared and connected and stacked to each other via electrodes on the
frames is indicated in Japanese Patent Laid-Open No. 2-198148. The U.S.
patent application Ser. No. 07/631154 also shows a similar technique, and
is pending now. In this shape, mounting in high density by stacking only
LSIs is realized. However, mounting in high density of functional parts
including chip parts which are necessary to improve the function of the
structural circuit is not taken into account. Therefore, it is required to
mount those function improving parts in the neighboring area of the
stacking type semiconductor device by soldering them later in the
conventional way and the entire function circuit unit is not always as
dense as desired.
As to parts which are mounted on products such as personal computers and
work stations which have been increasingly downsized, lightened, and
hyperfunctioned, the parts are requested to be miniaturized,
hyperfunctioned, and highly densified. When mounting LSIs which are used
for those apparatuses, tape carrier type semiconductor modules which are
characterized by being thin are frequently used at present.
Chip parts such as capacitors for improving characteristics of a
semiconductor device during high speed operation and for protecting the
semiconductor device from power noise are mounted in the neighboring area
of the semiconductor device. Therefore, even if the semiconductor device
and parts are miniaturized as far as possible, an increase in the mounting
area corresponding to a semiconductor device cannot be ignored due to the
wiring area of the chip parts in the neighboring area of the device.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a semiconductor device,
which is free from the problem inherent in the aforementioned prior art,
and wherein the wiring around the semiconductor device when parts are
mounted on a substrate is simplified, and the number of input and output
terminals is reduced, and the variety of terminal position setting is
increased. Another object of the present invention is to provide the
structure of a semiconductor device for modularizing the semiconductor
device in the highly hyperfunctioned and densified state, reducing the
mounting area, and improving the performance. A further object of the
present invention is to provide a semiconductor device having a tape
carrier type semiconductor module wherein the performance is
hyperfunctioned and the mounting density is increased.
To accomplish the above objects, the semiconductor device of the present
invention is a semiconductor device with reinforcement having at least a
semiconductor module and frame such as, for example, a tape carrier type
semiconductor device with reinforcement, wherein circuit lines and
electrodes are formed in a section other than the semiconductor module of
the semiconductor device with reinforcement, and wherein chip parts such
as capacitors are mounted in that section. The frame can be a single layer
or multi-layer. When the thickness of the frame ranges from 0.6 mm to 1
mm, generally at most six wiring layers may be formed in the frame.
However, there is no need to restrict it.
The section where circuit lines and electrodes are formed and chip parts
are mounted is a part of a single layer or multi-layer frame or a section
on a thin substrate, which is newly connected to the frame, such as a
flexible circuit. The flexible circuit may be a known substrate, which is
generally 75 .mu.m to 125 .mu.m in thickness and made of polyimide.
However, the thickness is a problem of design and there is no need to
restrict it.
The frames are generally made of glass-epoxy, though the frame may be made
of ceramics. The frame thickness is often about 1.3 times of the chip
thickness of a semiconductor module. However, there is no need to restrict
it.
When, for example, a semiconductor chip mounted on a carrier tape is a DRAM
(an abbreviation for dynamic random access memory), a capacitor having a
capacitance of about 0.1 to 1 .mu.F is used generally for two memory chips
so as to reduce power noise and to improve the high frequency
characteristics during high speed operation.
When these chip parts 3 are mounted on a substrate 17 around a
semiconductor device as shown in FIG. 11, the mounting area in the section
other than where the parts are mounted is spread. However, when the
structure of the present invention is used, chip parts are built in a
composite of semiconductor module and reinforcement frame or circuit lines
of a flexible circuit, so that the circuit lines on the mother board can
be simplified. Since the entire mounting structure is arranged
three-dimensionally, the mounting area can be reduced substantially.
According to the basic structure that a tape carrier type semiconductor
module 1 and frame 2 are electrically connected, it is possible to stack a
plurality of layers by making the best use of the thin structure, to
improve the performance, and to increase the mounting density. Also in
this case, the chip parts 3 such as capacitors in the necessary number
corresponding to the number of semiconductor chips incorporated in the
device are soldered and mounted later in the conventional way. In the case
of an SOJ (an abbreviation for small outline J-lead package) package
having no stacking structure, by using the space between another device
and the substrate, chip type parts can be mounted in the gap right under
the device. However, as to a semiconductor device using a tape carrier
type semiconductor module which is characterized by being thin, it is
necessary to mount it without a gap being provided on the substrate so as
to reduce the thickness of the entire circuit substrate when it is
mounted. A special method for mounting chip parts in a depression which is
formed in the substrate right under the semiconductor device may be used,
though the cost is increased.
According to the structure of the present invention, the chip parts 3 for
improving characteristics can be built in a semiconductor device (for
example, a tape carrier type semiconductor device) in the
three-dimensional shape, so that, for example, an extra increase in the
mounting area other than the tape carrier type semiconductor module 1 and
frame 2 can be stopped. In addition, circuit lines are built in the
semiconductor device, so that the circuit lines on the substrate can be
simplified and the number of input and output terminals for each
semiconductor device can be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic perspective view for explaining the basis structure
of a semiconductor device of an embodiment of the present invention;
FIG. 2 is a schematic perspective view showing the structure of a
multi-layered frame of an embodiment of the present invention;
FIGS. 3a and 3b are partially enlarged perspective views showing a tape
carrier type semiconductor device having a multi-layered frame of an
embodiment of the present invention;
FIG. 4 is a perspective view of a frame having a heat radiation pattern on
the surface of an embodiment of the present invention;
FIG. 5 schematic exploded perspective view showing a tape carrier type
semiconductor device using a flexible circuit for internal circuit lines
of another embodiment of the present invention;
FIG. 6 is an enlarged perspective view for explaining the connection parts
of a frame, flexible circuit, and tape carrier type semiconductor module
of another embodiment of the present invention;
FIG. 7 is a schematic perspective view showing the bonding status of a
frame and flexible circuit by thermosetting resin of another embodiment of
the present invention;
FIG. 8 is a perspective view showing an embodiment of a tape carrier type
semiconductor device wherein chip parts are mounted on a flexible circuit;
FIGS. 9a and 9b are perspective views showing an embodiment of a tape
carrier type semiconductor device wherein a flexible circuit is used as a
heat radiation
FIG. 10 is a schematic perspective view showing the structure of a stacked
tape carrier type multi-chip semiconductor device of a further embodiment
of the present invention; and
FIG. 11 is a schematic perspective view of an electronic circuit device of
a further different embodiment of the present invention wherein a
plurality of tape carrier type semiconductor devices are mounted on a
substrate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiment 1
The basic structure of the present invention using a tape carrier type
semiconductor module 1 and frame 2 for reinforcing it, which is made of
glass-epoxy, are shown in FIG. 1. The TAB (an abbreviation for tape
automated bonding) technique, which is conventionally used, is used for
bonding the tape carrier to the semiconductor chip. Epoxy resin is coated
on the electrodes of the semiconductor chip and tape carrier which are
bonded by the TAB technique and the neighboring area by potting or molding
so as to protect the electrodes and connected part. To protect the tape
carrier type semiconductor module 1 and frame 2 from interference in
shape, the tape carrier type semiconductor module 1 is bonded electrically
to the frame 2 which has a device hole 18 formed therein.
For bonding the frame 2 to the tape carrier type semiconductor module 1, a
method is used wherein electrodes, which are formed on the frame by
etching the coated conductor layer or electroless copper plating are
plated with solder, and lead electrodes 4 with solder plating on the tape
carrier type semiconductor module are positioned and reflow-soldered to
the frame electrodes. In FIG. 1, numeral 21 indicates a tape carrier which
is made of polyimide resin. The tape carrier is used to support the lead
electrodes 4 of the semiconductor chip.
Instead of a conventional frame, wherein electrodes which are used to
electrically bond the tape carrier type semiconductor module and frame and
foot patterns which are used to mount the semiconductor device on the
substrate 17 are provided on the top and bottom surfaces and through holes
for connecting the electrodes and foot patterns are formed, by using a
multi-layer wiring frame 22 having four wiring layers including the top
and bottom surfaces of the frame and two inner wiring layers as shown in
FIG. 2, circuit lines 7 and electrodes 19 can be formed within the frame.
According to this method, the degree of freedom of the circuit lines in the
frame can be increased, so that each electrode can be moved to an optional
location. By miniaturizing through holes for electrically shorting each
layer when a multi-layered substrate is used by using landless through
holes 8 having no land 9', as shown in FIG. 3a, the external size of the
frame can be minimized and the electrode pitch of the tape carrier frame
can be reduced. FIG. 3b shows through holes 9 having lands.
Chip parts are bonded beforehand to the mounting electrodes 19 shown in
FIG. 2 with Pb-Sn solder with a melting point of 250.degree. C. The reason
is to carry out hierarchical soldering which can sufficiently withstand
210.degree. C. at which the tape carrier type semiconductor module 1 and
frame 2 are reflow-soldered.
Depressions are formed in the neighboring area of the electrodes 19, shown
in FIG. 2, on the frame 2 whereon the chip parts 3 are mounted by the
fabricating operation shown in FIGS. 3a and 3b and the chip parts 3 are
prevented from protrusion from the frame, so that the external size can be
minimized. The electrodes 19 for mounting the chip parts are positioned so
that they do not interfere with the electrodes of the tape carrier type
semiconductor module 1 and frame 2.
To increase the effect of a capacitor so as to remove noise and to improve
the high frequency characteristics, it is necessary to connect the
capacitor in the neighborhood of the target semiconductor part at a short
wiring distance as far as possible so as to reduce the line impedance. By
mounting the capacitor via the circuit line on the frame, the effect can
be improved. The thickness of the tape carrier type semiconductor module
depends on the resin thickness on the chip surface and the thickness of
the semiconductor chip. However, the thickness of the semiconductor chip
can be thinned to about 0.2 to 0.3 mm by grinding, so that the thickness
of the entire device can be made thinner than that of a resin mold type
package such as an SOP (small outline package) with a height of about 3
mm. Resin is adhered by potting and the thickness is generally at most 80
.mu.m. According to this embodiment, the thickness is about 45 .mu.m. The
frame thickness is about 1.3 times of the chip thickness.
As a material of the frame, when a semiconductor chip with high power
consumption is mounted, ceramics with high thermal conductivity such as
silicon nitride or alumina to take into consideration the heat radiation
from the parts and heat resistance. In such a case, the ceramic material
is used as a heat radiation member or heat conduction path to the
substrate. Furthermore, a part of the circuit lines on the frame surface
may be spread and used as a heat radiation pattern 10.
Embodiment 2
A structure example that the tape carrier type semiconductor module 1 and
frame 2 shown in Embodiment 2 are used as a basic structure unit and a
flexible circuit 11 which has no device hole and can be wired is used is
shown in FIG. 5. The flexible circuit 11 is a polyimide film with a
thickness of about 125 .mu.m and circuit lines are formed on both sides
thereof using copper foil. According to this method, there are no
restrictions on the circuit line dimensions due to the device hole 18 at
the mounting location of the tape carrier type semiconductor module and to
the through holes 8 of the frame 2, so that the circuit line width can be
spread or the circuit line scale can be increased. Furthermore, the
electric characteristics can be improved (for example, reduction of
electromagnetic noise) due to increase in the circuit line width and
thickness. In this case, in addition to electrodes 6 which are used to
connect the tape carrier type semiconductor module 1, electrodes 7' which
are used to electrically connect the flexible circuit 11 are formed on the
frame 2 as shown in FIG. 6. In FIG. 6, a tape carrier type semiconductor
module wherein lead electrodes 4 are extended from the four sides is used
as a tape carrier type semiconductor module 1. To connect the tape carrier
type semiconductor module 1 and frame 2, a method that they are positioned
and connected against the frame surface in a batch and a method that as to
the frame 2 and flexible circuit 11 shown in FIG. 7, the frame 2 is bonded
to the flexible circuit 11 with heat resistant resin 15 such as polyimide
resin and the electrical continuity between the tape carrier type
semiconductor module and flexible circuit is ensured by the copper-plated
through holes 8 formed so as to pass through the frame from the flexible
circuit are used.
According to a structure example that a circuit line 12 is formed on the
above flexible circuit 11, it is necessary only to form through holes,
which are used to connect the electrodes on the top and bottom surfaces of
the frame for the tape carrier type semiconductor module and the
electrodes for mounting the substrate, on the frame 2. Therefore, the cost
can be decreased by simplifying the frame wiring and the number of
electrode pins for the tape carrier type semiconductor module can be
increased.
The electrodes for mounting the substrate may be formed on the flexible
circuit or at a part where the frame and flexible circuit are integrated.
The chip parts 3 for improving the electric characteristics may be mounted
to the electrodes on the frame as shown in FIG. 5 or to the electrodes on
the flexible circuit 11 for leading the circuit lines as shown in FIG. 8.
According to this embodiment, the chip parts are mounted on the flexible
circuit. In either case, to prevent an increase in size due to the chip
parts and to protect interference with the neighboring part, depressions
are formed in the neighboring area of the electrodes for mounting the chip
parts in accordance with the shape of the chip parts 3.
When ceramics such as silicon nitride with high thermal conductivity are
used as a frame material, the frame ensures a heat radiation path when LSI
with high power consumption and a high calorific value are mounted and can
be used as a heat radiation fin.
For example, a copper foil heat radiation pattern 16 which is not related
to the circuit lines may be formed directly on the end face of the
flexible circuit as shown in FIGS. 9a and 9b so as to use a heat radiation
fin.
Numeral 5 shown in FIG. 5 and others indicates a depression, and numeral 14
shown in FIG. 6 and others indicates an electrode for connecting the
flexible circuit and frame, and numeral 13 indicates an electrode for
connecting the semiconductor device of the present invention to the
substrate 17.
Embodiment 3
By stacking semiconductor devices wherein the tape carrier type
semiconductor module 1 and frame 2 shown in Embodiments 1 and 2, flexible
circuit 11, and chip parts 3 connected on the frame 2 constitute a basic
structure using an adhesive, for example, such as epoxy resin as shown in
FIG. 10, the equipment can be highly densified and hyperfunctioned
furthermore. In this case, when a DRAM is mounted as an LSI, one capacitor
or so is used per two memory chips so as to reduce the power noise and to
improve the characteristics during high speed operation. The power circuit
between the power unit and capacitor for each chip and the chip select
circuit for determining the layer where the chip operates can be wired
inside the semiconductor device, so that the wiring electrodes on the
substrate where the semiconductor device is mounted, particularly in the
neighboring area of the semiconductor device can be simplified.
For example, when a flexible circuit 11 wherein multi-layer circuit lines
are formed is used, the restriction on the number of electrodes caused by
interference between the through holes and foot print and the restriction
on the arrangement thereof can be removed by changing the location of each
electrode. Since the chip parts 3 are mounted in the device
three-dimensionally, no mounting area for the chip parts is required for
the part mounting substrate. Even if the number of stacking chips is
increased and the number of accessory parts is increased, the mounting
area can be reduced and parts can be mounted in high density.
Embodiment 4
An application example of a semiconductor device including stacked devices
having the tape carrier type semiconductor module 1, frame 2, flexible
circuit 11, and chip parts 3 of the present invention, described in
Embodiment 3, which are basic elements and electrically connected so as to
form a circuit, wherein mounted LSIs are used as memories and the memory
capacity of each device is increased by times of the number of layers
without the mounting area being changed is shown. The structure is the
same as that shown in FIG. 10. When the memory LSIs in the device operate
at high speed, noise is generated in the power unit and ground layer by
the circuit line impedance in the device. Therefore, chip capacitors with
a capacity of 0.1 to 1 .mu.F are used as chip parts 3 so as to reduce it.
Using the structure of the present invention, chip parts in the number
corresponding to the number of memory LSIs in the device are built in. A
chip select circuit for selecting the chip operation is also built in the
flexible circuit 11.
According to the structure containing no chip parts 3 indicated in Japanese
Patent Laid-Open No. 2-198148, although depending on the power consumption
of each LSI, when a heat radiation pattern using copper foil with a
thickness of 35 .mu.m is mounted on the surface of a 4-MB DRAM with power
consumption of at most 0.5 W, and the thermal conductivity of the
substrate is improved, and heat is effectively radiated in the atmosphere,
the DRAM can operate simultaneously with at most about four stacked layers
(2 W for each semiconductor device). In this case, the chip capacitors are
mounted outside the layers. When stacking LSIs having a calorific value
higher than it, it is necessary to use a material with high thermal
conductivity such as ceramics as a substrate and to use the substrate
positively as a heat radiation fin. A material with high thermal
conductivity is also used as a material of the frame 2 so as to reduce the
thermal resistance between the parts and substrate. The heat radiation of
the equipment mentioned above, which is indicated in Japanese Patent
Laid-Open No. 2-198148, is the same as that of the semiconductor device
with reinforcement of the present invention. According to the tape carrier
type semiconductor device with built-in chip capacitors of this
embodiment, a device having, for example, memory LSIs and logic LSIs such
as micro-processors or address decoders which are mixed and stacked has a
function which is the same as that of the current on-board type memory
module and a semiconductor device with external dimensions which are
similar to those of an SOJ type device can be formed.
Embodiment 5
A device is formed by stacking four layers in the state that a tape carrier
type DRAM 1M words by 4 bits long is used and ceramic capacitors 3 with a
capacity of 0.1 to 1 .mu.F for improving characteristics are mounted on
the frame 2, and 8 devices are mounted on a substrate 17 for a 72-pin SIMM
(single in-line memory module) under the IEEE specification, and a 16-MB
memory module is formed. The shape of three devices which are mounted is
shown in FIG. 11. In the case of a conventional TSOP (thin small outline
package), although depending on the mounting pitch, at most about 9 LSIs
can be mounted. However, according to the structure of the present
invention, when a mounting area which is similar to that of a TSOP can be
ensured, four times of LSIs can be mounted. Several LSI layers mounted on
a tape carrier type package are used as an address decoder and parts for
improving characteristics are mounted and stacked on the frame 2. By
mounting devices on both the top and bottom surfaces of the substrate 17,
the device mounting pitch can be spread as far as possible and a free area
can be formed between neighboring devices, so that even if the substrate
is changed to a one with high thermal conductivity due to changing of the
material, the heat radiation efficiency from each device into the
atmosphere can be increased and LSIs with high power consumption can be
mounted on it.
For example, to improve the thermal conductivity of the substrate, a
substrate wherein the inner copper foil content is increased can be used.
As obvious from the above embodiments, according to the semiconductor
device with reinforcement of the present invention, there is no need to
solder capacitors for improving high frequency characteristics later and
devices can be mounted in high density in a small mounting area, so that
it is suitable to semiconductor devices used in personal computers and
work stations and the entire device can be miniaturized and
hyperfunctioned.
In the aforementioned drawings, each same numeral indicates the same part.
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