U.S. patent application number 09/465755 was filed with the patent office on 2001-08-16 for ball-grid-array semiconductor with protruding terminals.
Invention is credited to ABE, MASAAKI.
Application Number | 20010013639 09/465755 |
Document ID | / |
Family ID | 18479614 |
Filed Date | 2001-08-16 |
United States Patent
Application |
20010013639 |
Kind Code |
A1 |
ABE, MASAAKI |
August 16, 2001 |
BALL-GRID-ARRAY SEMICONDUCTOR WITH PROTRUDING TERMINALS
Abstract
There is provided a ball-grid-array semiconductor device. The
semiconductor device has a semiconductor element sealed with a
resin material. In addition, a lead frame is connected to the
semiconductor element in the resin material. The lead frame is
provided with terminal portions that protrude through the surface
of the resin material.
Inventors: |
ABE, MASAAKI; (KUMAMOTO,
JP) |
Correspondence
Address: |
MCGINN & GIBB PC
1701 CLARENDON BOULEVARD
SUITE 100
ARLINGTON
VA
22209
|
Family ID: |
18479614 |
Appl. No.: |
09/465755 |
Filed: |
December 17, 1999 |
Current U.S.
Class: |
257/666 ;
257/675; 257/676; 257/684; 257/690; 257/692; 257/693; 257/694;
257/696; 257/698; 257/E21.528; 257/E21.53; 257/E23.039 |
Current CPC
Class: |
H01L 24/48 20130101;
H01L 23/4951 20130101; H01L 2224/73265 20130101; H01L 22/26
20130101; H01L 2224/48247 20130101; H01L 2924/00014 20130101; H01L
2924/01078 20130101; H01L 2924/15311 20130101; H01L 2224/16
20130101; H01L 2924/12042 20130101; H01L 2924/14 20130101; H01L
22/12 20130101; H01L 2224/32014 20130101; H01L 2224/05599 20130101;
H01L 2224/48095 20130101; H01L 2924/181 20130101; H01L 2224/85399
20130101; H01L 2224/48095 20130101; H01L 2924/00014 20130101; H01L
2924/12042 20130101; H01L 2924/00 20130101; H01L 2924/181 20130101;
H01L 2924/00012 20130101; H01L 2224/85399 20130101; H01L 2924/00014
20130101; H01L 2224/05599 20130101; H01L 2924/00014 20130101; H01L
2924/00014 20130101; H01L 2224/45015 20130101; H01L 2924/207
20130101; H01L 2924/00014 20130101; H01L 2224/45099 20130101; H01L
2924/14 20130101; H01L 2924/00 20130101; H01L 2224/73265 20130101;
H01L 2224/32245 20130101; H01L 2224/48247 20130101; H01L 2924/00012
20130101 |
Class at
Publication: |
257/666 ;
257/684; 257/675; 257/676; 257/693; 257/696; 257/690; 257/692;
257/694; 257/698 |
International
Class: |
H01L 023/495; H01L
023/06; H01L 023/48; H01L 023/52; H01L 023/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 21, 1998 |
JP |
10-363557 |
Claims
What is claimed is:
1. A ball-grid-array semiconductor device comprising: a
semiconductor element; a resin material which seals said
semiconductor element; and a lead frame connected to said
semiconductor element in said resin material, said lead frame
having a terminal portion that protrudes through a surface of said
resin material.
2. The ball-grid-array semiconductor device according to claim 1,
which further comprising a solder layer formed on an edge surface
of said terminal portion.
3. The ball-grid-array semiconductor device according to claim 1,
which further comprising a bonding wire which connects said
semiconductor element to said lead frame.
4. The ball-grid-array semiconductor device according to claim 1,
wherein said terminal portion is formed by etching a sheet of
metal, a material of said lead frame, substantially half of the
thickness thereof.
5. A method for manufacturing a ball-grid-array semiconductor
device, comprising the steps of: forming a lead frame having a
terminal portion that protrudes in the direction of thickness
thereof; mounting a semiconductor element on said lead frame;
connecting an electrode provided on said semiconductor device to
the lead frame by means of a bonding wire; and sealing said
semiconductor element with a resin material, said terminal portion
protruding through a surface of said resin material.
6. The method for manufacturing a ball-grid-array semiconductor
device according to claim 5, which further comprising the step of
forming a solder layer on an edge surface of said terminal
portions.
7. The method for manufacturing a ball-grid-array semiconductor
device according to claim 5, wherein the step of forming said lead
frame comprises the step of etching a sheet of metal substantially
half of the thickness thereof.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a ball-grid-array
semiconductor device and a manufacturing method therefor, and more
particularly, to a ball-grid-array semiconductor device having a
lead frame with terminal portions formed to protrude by etching,
and its manufacturing method.
[0003] 2. Description of the Related Art
[0004] A package including a lead frame is available as one of
semiconductor device packages that have been manufactured to meet
the requirements for semiconductor devices such as
higher-integration, miniaturization, decreasing in thickness, and
higher pin count. A technique relating to a method for
manufacturing lead frames that is applicable to ball-grid-array
semiconductor devices is described in Japanese Patent Application
Laid-Open No. Sho 60 (1985)-52050. FIG. 1 is a cross-sectional view
showing a conventional semiconductor device having a lead frame
described in Japanese Patent Application Laid-Open No. Sho 60
(1985)-52050.
[0005] According to the prior art described in this publication, in
a process where a sheet of metal is etched to form a lead frame,
approximately a half of one side of the metal sheet is etched. This
allows for forming projected portions 110a for use as external
terminals on the side, which protrude in the direction of thickness
of the metal sheet. Subsequently, an integrated circuit 114 is
attached with a bonding portion 112 to the other side where the
projected portions 110a of the lead frame 110 have not been formed.
Then, these are sealed with resin 118. At this time, edges of the
projected portions 110a and part of the sides of the resin 118 are
coplanar. For the conventional semiconductor devices, such method
was employed to manufacture the lead frame 110 having terminals for
external connection in one process.
[0006] However, this presents a problem that it is difficult to
clean flux residues remaining between a package and a substrate
after the package has been mounted onto the substrate. This happens
because the edges of the projected portions 110a, or external
terminals, and part of sides of the resin 118 are coplanar.
[0007] A method of mounting solder balls onto the projected
portions 110a is available to solve this problem, however, this
method also presents a problem that material and manufacturing
costs are hardly reduced.
SUMMARY OF THE INVENTION
[0008] An object of the present invention is to provide a
ball-grid-array semiconductor device and manufacturing method
therefor, which facilitates cleaning flux residues remaining in
between the package and the substrate after having been mounted
onto the substrate, and which provides drastically reduced material
and manufacturing costs.
[0009] According to one aspect of the present invention, a
ball-grid-array semiconductor device comprises: a semiconductor
element; a resin material which seals the semiconductor element;
and a lead frame connected to the semiconductor element in the
resin material. The lead frame has a terminal portion that
protrudes through a surface of the resin material.
[0010] According to another aspect of the present invention, a
method for manufacturing a ball-grid-array semiconductor device
comprises the steps of: forming a lead frame having a terminal
portion that protrudes in the direction of thickness thereof;
mounting a semiconductor element on the lead frame; connecting an
electrode provided on the semiconductor device to the lead frame by
means of a bonding wire; and sealing the semiconductor element with
a resin material. The terminal portion protrudes through a surface
of the resin material.
[0011] The present invention allows the terminal portions to
protrude through the surface of the resin material. Thus, the
terminal portions can used as connecting terminals, as they are, to
be mounted directly to the substrate, and cleaning of flux residues
after mounting can be readily carried out. Therefore, conventional
ball-grid-array semiconductor devices have required solder balls to
be mounted on packages to facilitate cleaning flux residues,
whereas the present invention requires no such necessity, allowing
for providing remarkably reduced material and manufacturing
costs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a cross-sectional view showing a conventional
semiconductor device having a lead frame described in Japanese
Patent Application Laid-Open No. Sho 60 (1985)-52050.
[0013] FIG. 2 is a cross-sectional view showing the structure of a
ball-grid-array semiconductor device according to an embodiment of
the present invention.
[0014] FIG. 3 is a bottom view showing the structure of the
ball-grid-array semiconductor device according to the embodiment of
the present invention.
[0015] FIG. 4 is a view showing the method for manufacturing the
ball-grid-array semiconductor device according to the embodiment of
the present invention, illustrating the step where the device is
sealed with resin.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] The embodiment of the present invention is to be explained
specifically with reference to the accompanying drawings. FIG. 2 is
a cross-sectional view showing the structure of a ball-grid-array
semiconductor device according to the embodiment of the present
invention. FIG. 3 is a bottom view showing the structure of the
ball-grid-array semiconductor device similarly according to the
embodiment of the present invention.
[0017] A ball-grid-array semiconductor device 1 according to this
embodiment allows a semiconductor element 14 to be mounted with an
adhesive tape 12 on a lead frame 10 provided with terminal portions
10a which protrude in the direction of thickness thereof. The lead
frame 10 is formed, for example, by etching a sheet of metal
approximately a half of the thickness thereof.
[0018] Moreover, bonding wires 16 connect the lead frame 10 to
electrodes provided on the semiconductor element 14. Then, they are
sealed with a resin material 18 to be formed in a predetermined
package shape. Incidentally, the terminal portions 10a protrude
through the substrate mount surface of the resin material 18.
Moreover, a solder layer 19 is formed on the edges of the terminal
portions 10a.
[0019] The ball-grid-array semiconductor device 1 of this
embodiment constructed as such allows the terminal portions 10a, on
which the solder layer 19 is formed, to be used as terminals as
they are for being mounted on a substrate.
[0020] Incidentally, the terminal portions 10a can be etched into a
variety of shapes such as a cylinder or a rectangular column.
However, a cylindrical shape is desirable in which stress is
unlikely to occur, when considering the heat-cycle resisting
performance thereof after having been mounted on the substrate.
[0021] In addition, the terminal portions 10a have desirably a
height ranging from 0.1 to 0.3 mm from the substrate mount surface,
when considering the easiness of cleaning flux residues after
having been mounted.
[0022] Furthermore, the solder layer 19 to be formed on the edges
of terminal portions 10a is desirably about 5 to 10 .mu.m in
thickness, which is equivalent in thickness to a solder layer to be
applied to outer leads of resin-sealed semiconductor devices,
typified by conventional QFP (Quad Flat Pack) semiconductor
devices.
[0023] Next, a method for manufacturing the aforementioned
semiconductor device of this embodiment is to be explained. FIG. 4
is a cross-sectional view showing the method for manufacturing the
ball-grid-array semiconductor device according to the embodiment of
the present invention, illustrating the step where the device is
sealed with resin.
[0024] First, a sheet of metal is etched approximately by half the
thickness thereof to form a lead frame 10 having the terminal
portions 10a that protrude in the direction of thickness.
Subsequently, a semiconductor element 14 is mounted onto the lead
frame 10 with an adhesive tape. Then, the electrodes provided on
the semiconductor element 14 are connected to the lead frame 10 by
means of bonding wires 16.
[0025] Subsequently, as shown in FIG. 4, the lead frame 10, the
semiconductor element 14 and the like are sandwiched in between an
upper metal mold 22 having a cavity 22a of a predetermined shape
and a lower metal mold 20 having recessed portions 20a as a cavity
for accommodating the terminal portions 10a. Then, resin is allowed
to flow in from an injection portion (not shown) which is in
connection with the cavities 20a and 22a, thereby sealing the lead
frame 10 and the semiconductor element 14 with the resin.
[0026] After the encapsulation with the resin has been completed,
there will exist thin fins on the edges of the terminal portions
10a. Thus, those thin fins are removed by laser honing, sand
blasting, water jet honing or the like in order to allow the
terminal portions 10a of the lead frame 10 to be exposed.
Thereafter, a solder layer 19 is formed on the edges of the
terminal portions 10a.
[0027] Such method as mentioned above allows the terminal portions
10a of the lead frame 10 to protrude through the substrate mount
surface of the resin material 18.
[0028] As described above, this embodiment allows the terminal
portions 10a to protrude through the substrate mount surface of the
package and the solder layer 19 to be formed on the edges thereof.
Therefore, the terminal portions 10a can be used as connecting
terminals, as they are, for being mounted directly to the
substrate, and the cleaning of flux residues after the portions
have been mounted can be readily carried out. Therefore,
conventional ball-grid-array semiconductor devices have required
solder balls to be mounted on packages to facilitate cleaning flux
residues, whereas this embodiment requires no such necessity,
allowing for providing remarkably reduced material and
manufacturing costs.
* * * * *