Title: IC chip package
Abstract: An IC chip packaging comprises a carrier having a topside, a bottom side and a passage having an opening on the topside and another opening on the bottom side, a chip mounted on the topside of the carrier and covering the opening on the topside, a plurality of bonding wires each having one end electrically connected to said chip covered on the opening on the topside and an opposite end horizontally electrically connected to the bottom side of the carrier through the opening on the bottom side, and a protective member covering the opening on the bottom side and the opposite ends of the bonding wires. The protective member has a height vertically extended from a bottom side thereof to the carrier within 0.4 mm.
Patent Number: 6,984,896 Issued on 01/10/2006 to Wu
| Inventors:
|
Wu; Cheng-Chiao (No. 114, Chung San Rd., Taichung, TW)
|
| Appl. No.:
|
232695 |
| Filed:
|
September 3, 2002 |
Foreign Application Priority Data
| Nov 01, 2001[TW] | 90127111 A |
| Current U.S. Class: |
257/784 |
| Current Intern'l Class: |
H01L 23/48 (20060101); H01L 23/52 (20060101); H01L 29/40 (20060101) |
| Field of Search: |
257/735,784,787
|
References Cited [Referenced By]
U.S. Patent Documents
Primary Examiner: Zarneke; David A.
Attorney, Agent or Firm: Browdy and Neimark, PLLC
Claims
What the invention claimed is:
1. An IC chip packaging comprising:
a carrier having a topside, a bottom side and a passage having an opening on
the topside and another opening on the bottom side;
a chip mounted on the topside of the carrier and covering the opening on the topside;
a plurality of bonding wires, said bonding wires each having one end electrically
connected to said chip covered on the opening on the topside and an opposite end
horizontally electrically connected to the bottom side of the carrier through the
opening on the bottom side; and
a first protective member is formed at least in part as a thin sheet member which
is flat on both an upper and a bottom side thereof covering the opening on the
bottom side of the carrier and the opposite ends of the bonding wires, said thin
sheet member having a depth vertically extended from a bottom side thereof to said
carrier within 0.4 mm; and wherein said thin sheet member flattens said opposite
ends of said bonding wires toward the bottom side of the carrier when engaged to
the carrier.
2. The IC chip package as claimed in claim 1, wherein the height extended vertically
from the bottom side of said thin sheet member to said carrier is preferably within
0.08~0.125 mm.
3. The IC chip package as claimed in claim 1, wherein said thin sheet member
is bonded to the bottom side of said carrier by a bonding agent and covered over
the opening on the bottom side and the opposite ends of the bonding wires.
4. The IC chip package as claimed in claim 1, wherein said first protective member
is made of one of synthesized resins including epoxy resin and silicon resin and
directly molded on the opening on the bottom side and said opposite ends of said
bonding wires.
5. The IC chip package as claimed in claim 3, further comprising a second protective
member made of one of synthesized resins including epoxy resin and silicon resin
and directly sealed in said passage above said thin sheet member.
6. The IC chip package as claimed in claim 1, further comprising a chip shield
covered on said carrier to encapsulate said chip.
7. The IC chip package as claimed in claim 6, wherein said chip shield is a plate
member made of material selected from a group of materials including opaque plastics,
metal, transparent glass, and transparent plastics, and bonded to said carrier
to protect said chip.
8. The IC chip package as claimed in claim 6, wherein said chip shield is made
of one of synthesized resins including epoxy resin and silicon resin, and directly
molded on said chip.
9. The IC chip package as claimed in claim 6, wherein said chip shield comprises
a plurality of locating rods adapted for holding said carrier in place when bonding
said carrier to an external circuit board.
10. The IC chip package as claimed in claim 1, wherein said carrier further comprises
a conductive circuit pattern on the bottom side adapted for connecting an external
circuit board, the conductive circuit having a plurality of bonding pads electrically
connected to the opposite ends of the bonding wires.
11. The IC chip package as claimed in claim 10, wherein said thin sheet member
covers over the conductive circuit pattern and the bonding pads, the thin sheet
member having at least one through hole corresponding to the conductive circuit
pattern and inserted therein with an electrically conducting glue for enabling
said conductive circuit pattern to be electrically connected to an external circuit board.
12. The IC chip package as claimed in claim 11, further comprising at least one
electrically conducting member embedded in said at least one through hole.
13. The IC chip package as claimed in claim 1, wherein said carrier is a single-layer
circuit board.
14. The IC chip package as claimed in claim 1, wherein said carrier is a laminated
circuit board.
15. The IC chip package as claimed in claim 1, wherein said carrier is comprised
of a plurality of contact leads.
16. The IC chip package as claimed in claim 1, wherein the thin sheet member
is preformed.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an IC chip package and, more specifically, to
a small size IC chip package, which greatly reduces the dimensions of the whole package.
2. Description of the Related Art
Because regular IC chips are fragile, they must be well packaged and protected
against external force. After packaging of an IC chip, the IC chip can be effectively
electrically connected to an external circuit board. Following fast and free development
of high-tech, IC chip packages are made lighter, thinner, shorter, and smaller.
FIG. 1 illustrates an IC chip package
1 according to the prior art. According
to this design, the IC chip package
1 comprises a substrate
3, the
substrate
3 having a passage
3a through the top and bottom
sides thereof, a chip
2 fixedly mounted on the topside of the substrate
3, the chip
2 having a plurality of bonding pads
2a disposed
at one end of the passage
3a, a plurality of bonding wires
4
extended through the passage
3a, the bonding wires
4 each
having one end respectively connected to the bonding pads
2a of the
chip
2 and the other end connected to bonding pads
3b on the
substrate
3, two protective covers
5,
5′ respectively
covered on the chip
2 and the bonding pads
3b and bonding
wires
4 of the substrate
3, a solder mask
7 covered over the
circuits
6 of the substrate
3, and a plurality of solder balls
8
respectively electrically connected to the conductive circuit pattern
6
outside the solder mask
7 and adapted for connecting the conductive circuit
pattern
6 to tin solder paste
9a pre-applied on an external
circuit board
9.
According to the aforesaid package
1, the bottom side of the substrate
3 must leave sufficient space for receiving bonding wires so that the bonding
wires
4 can be extended through the passage
3a and connected
between the bonding pads
2a at the chip
2 and the bonding
pads
3b at the substrate
3. When the protective cover
5′
covered on the whole area of the bonding pads
3b on the substrate
3b and the bonding wires
4, the vertical height H of the protective
cover
5′ between the bottom side of the protective cover
5′
and the substrate
3 is tall. Therefore, a relatively higher interface must
be used for enabling the substrate
3 to be electrically connected to the
external circuit board
9, i.e., the solder balls
6 must be greater
than the vertical height H of the protective cover
5′ for soldering
to the solder paste
9a at the external circuit board
9. According
to this design, the vertical height of the solder balls
6 is about 0.5 mm.
The use of the big solder balls
6 greatly increases the dimensions of the
IC chip package
1.
SUMMARY OF THE INVENTION
The present invention has been accomplished under the circumstances in view.
It is one object of the present invention to provide an IC chip package, which
greatly reduces the dimensions of the whole package.
To achieve the object of the present invention, an IC chip packaging comprises
a carrier having a topside, a bottom side and a passage having an opening on the
topside and another opening on the bottom side, a chip mounted on the topside of
the carrier and covering the opening on the topside, a plurality of bonding wires
each having one end electrically connected to said chip covered on the opening
on the topside and an opposite end horizontally electrically connected to the bottom
side of the carrier through the opening on the bottom side, and a protective member
covering the opening on the bottom side and the opposite ends of the bonding wires.
The protective member has a height vertically extended from a bottom side thereof
to the carrier within 0.4 mm.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing an IC chip package constructed according
to the prior art.
FIG. 2 is an exploded view of an IC chip package constructed according to a
first embodiment of the present invention.
FIG. 3 is a sectional view of the first embodiment of the present invention
showing the IC chip package installed in an external circuit board.
FIG. 4 is a sectional view of an IC chip package constructed according to a
second embodiment of the present invention.
FIG. 5 is a sectional view of an IC chip package constructed according to a
third embodiment of the present invention.
FIG. 6 is a sectional view of an IC chip package constructed according to a
fourth embodiment of the present invention.
FIG. 7 is a sectional view of an alternate form of the IC chip package according
to the fourth embodiment of the present invention.
FIG. 8 is a sectional view of an IC chip package constructed according to a
fifth embodiment of the present invention.
FIG. 9 is a bottom view of the fifth embodiment of the present invention after
removal of the external circuit board.
FIG. 10 is a bottom view of an IC chip package constructed according to a sixth
embodiment of the present invention.
FIG. 11 is a sectional view taken along line 11—11 of FIG. 10.
FIG. 12 is a sectional view of an IC chip package constructed according to a
seventh embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 2 and 3, an IC chip package
10 in accordance
with the present invention is shown comprised of a carrier
11, a chip
12,
bonding wires
13, a chip shield
14, and a protective member
15
in the form of a preformed flat thin sheet member.
The carrier
11 is a PCB (printed circuit board) made of plastics, fiberglass
reinforced plastic material, ceramics, etc., having a bottom side
11a,
a topside
11e opposite to the bottom side
11a, a predetermined
conductive circuit pattern
11b arranged on the bottom side
11a,
a plurality of bonding pads
11c arranged in the bottom side
11a
and respectively connected to the conductive circuit pattern
11b,
a passage
11f cut through the bottom side
11a and the
topside
11e, i.e. the passage has an opening on the topside of the
carrier and another opening on the bottom side of the carrier, and an solder mask
11d covered on the bottom side
11a over the conductive
circuit pattern
11b, leaving a part of the circuit pattern
11b
to be exposed to the outside for connection to external electric conducting
means. The PCB of the carrier
11 can be a single layer PCB or laminated
PCB. For illustration purpose only, the PCB shown in the drawings is a single layer PCB.
The chip
12 (for easy understanding of the present invention, only one
chip is used) is bonded to the topside
11e of the carrier
11
directly by a bonding material
12a, for example, epoxy resin, silicon
resin, glass of low melting point, or double-side glue, covering the opening of
the passage on the topside. The chip has a plurality of bonding pads
12b
corresponding with the passage
11f.
The bonding wires
13 are made of gold or aluminum alloy, each having one
end respectively fastened to the bonding pads
12b of the chip
12
by a bonding tool (not shown) and an opposite end substantially horizontally connected
to the bonding pads
11c on the bottom side
11a of the
carrier
11 through the passage. Because the bonding wires
13 each
have a part horizontally extended outside the passage
11f and respectively
connected to the bonding pads
11c in the bottom side
11aof
the carrier
11, the height of the bonding wires
13 at the bottom
side
11a of the carrier
11 is minimized.
The chip shield
14 can be an opaque cover member made of plastics or metal,
or a transparent cover member made of glass or plastics, having a topside
14a
and a bottom side
14b. The bottom side
14b has
a center area recessed, forming a receiving chamber (not shown). The bottom side
14b is bonded to the topside
11e of the carrier
11
through an adhesive material (not shown), keeping the chip
12 protected
in the receiving chamber in the bottom side
14b of the chip shield
14 against outside force or contamination.
The flat thin sheet member
15 according to this embodiment is a thin sheet
member having a width greater than the distance between the bonding pads
11c
in the bottom side
11a of the carrier
11 at two sides
of the passage
11f. The flat thin sheet member
15 is bonded
to the bottom side
11a of the carrier
11 by a bonding agent
15a, and covered over the bonding pads
11c, the passage
11f and flattens the bonding wires
13 against the bottom side
11a of the carrier
11 (see FIG. 3) . As illustrated in FIG.
3, when installed, the height H′ of the protective member
15 does
not surpass 0.4 mm. Preferably the height H′ of the protective member
15
is within 0.08˜0.125 mm (because the height of tin solder paste is about
0.15 mm, tin soldering paste can be maintained in direct contact with the carrier
without interfering with the protective member if the thickness of the protective
member is maintained within 0.08˜0.125 mm)
Referring to FIG. 3 again, when installing the IC chip package
10
in an external circuit board
16, a conducting glue, for example, tin soldering
paste
16a is applied to the circuit board
16 corresponding
to the exposed part of the conductive circuit pattern
11b. By means
of tin soldering paste
16a, the external circuit board
16
is bonded to the exposed part of the conductive circuit pattern
11b in
the bottom side
11a of the carrier
11 of the IC chip package
10, keeping the bonding wires
13 electrically connected to the external
circuit board
16. Because the cover height of the thin sheet member is smaller
than 0.4 mm (lower than the height 0.5 mm of solder balls), it is not necessary
to use relatively taller solder balls as interface means for electric connection,
and the tin soldering paste
16a directly electrically connects the
external circuit board
16 to the conductive circuit pattern
11b
in the bottom side
11a of the carrier
11 of the IC chip
package
10. Therefore, this design greatly reduces the packaging procedure
and dimensions.
FIG. 4 shows an IC chip package
20 constructed according to the second
embodiment of the present invention. According to this embodiment, the IC chip
package
20 is comprised of a carrier
21, a chip
22, a chip
shield
23, bonding wires
24,and a protective member
25. The
main features of this embodiment are outlined hereinafter.
The carrier
21 is a plate member having a bottom side
211, a topside
212, and a passage
213 cut through the bottom side
211 and
the topside
212.
The chip
22 is directly bonded to the topside
212 of the carrier
21.
The chip shield
23 is made of synthesized resin, for example, epoxy resin
or silicon resin, and directly molded on the chip
22, keeping the chip
22
well protected by the chip shield
23.
The protective member
25 is made of synthesized resin, for example, epoxy
resin or silicon resin, and directly molded on the bonding pads
214 and
the bonding wires
24 in the bottom side
211 of the carrier
21
to seal the passage
213. Because the bonding wires
24 are horizontally
extended outside the passage
213 and respectively connected to the bonding
pads
214 in the bottom side
211 of the carrier
21, the height
of the bonding wires
24 in the bottom side
211 of the carrier
21
is minimized so that the height of the protective member
25 after installation
can be reduced to the level below 0.4 mm.
FIG. 5 shows an IC chip package
30 constructed according to the third
embodiment of the present invention. According to this embodiment, the IC chip
package
30 is comprised of a carrier
31, a chip
32, bonding
wires
34, a chip shield
33, and a protective member
35. The
main features of this embodiment are outlined hereinafter.
The protective member
35 is a thin sheet of plate member.
The passage
314 of the carrier
31 is sealed with a second protective
member
36. The second protective member
36 is made of synthesized
resin, for example, epoxy resin or silicon resin, and directly molded in the passage
314 to protect the bonding pads
321 of the chip
32 and the
bonding pads
315 of the carrier
31.
FIG. 6 shows an IC chip package
40 constructed according to the fourth
embodiment of the present invention. According to this embodiment, the IC chip
package
40 is comprised of a carrier
41, a chip
42, a chip
shield
43, bonding wires
44,and a protective member
45. The
main features of this embodiment are outlined hereinafter.
The protective member
45 is a thin sheet member. The width and area of
the protective member
45 are greater than the combined width and area of
the conductive circuit pattern
412 and the bonding pads
411 in the
carrier
41 so that the protective member
45 covers the conductive
circuit pattern
412 and the bonding pads
411 when installed in the
carrier
41. The protective member
45 has at least one through hole
451 corresponding to a predetermined portion of the conductive circuit pattern.
By means of applying an electrically conducting glue, for example, tin paste
461
in the through hole
451, the conductive circuit pattern
412 are electrically
connected to the external circuit board
46 on which the IC chip package
is installed. Therefore, the protective member
45 protects the bonding pads
411 and conductive circuit pattern
412 of the carrier
41 against
influence or destruction of external force.
As indicated above, the arrangement of the protective member
45 well protects
the conductive circuit pattern
412 against destruction of external force.
Therefore, it is not necessary to employ the conventional solder mask to protect
the conductive circuit pattern
412 of the carrier
41.
Referring to FIGS. 7 and 7A, the protective member
45 is made having
two serial through holes
451′,
452 respectively mounted with
conducting member
47 made of gold, silver, tin, or lead. The conducting
member
47 is bonded to the conductive circuit pattern
412 of the
carrier
41 by soldering, plating, print, etc. The conducting member
47
is embedded in the through holes
451′,
452. During installation
of the IC chip package
40 in the external circuit board
46, tin soldering
paste
461 is applied to the conducting member
47 and the external
circuit board
46, keeping the conductive circuit pattern
412 of the
carrier
41 electrically connected to the external circuit board
46
without increasing the dimensions between the carrier
41 and the external
circuit board
46.
FIGS. 8 and 9 show an IC chip package
50 constructed according to the
fifth embodiment of the present invention. According to this embodiment, the IC
chip package
50 is comprised of a carrier
51, a chip
52, a
chip shield
53, bonding wires
54, and a protective member
55.
The main features of this embodiment are outlined hereinafter.
The carrier
51 is made of metal and formed of a plurality of contact leads
for carrying the chip
52 and electrically connecting the chip
52
to an external circuit board. The protective member
55 is a thin sheet member.
FIGS. 10 and 11 show an IC chip package
60 constructed according to
the sixth embodiment of the present invention. According to this embodiment, the
IC chip package
60 is comprised of a carrier
61, a chip
62,
a chip shield
63, bonding wires
64, and a protective member
65.
The main features of this embodiment are outlined hereinafter.
The chip shield
63 has a plurality of downward locating rods
631
suspended around the periphery of the carrier
61 and downwardly protruded
over the bottom side
611 of the carrier
61 at a distance about 0.4
mm. When bonding the carrier
61 to the external circuit board
66
with a bonding agent
67, the downward locating rods
631 of the chip
shield
63 hold the carrier
61 on the external circuit board
66
for positive positioning, preventing excessive displacement of the carrier
61
relative to the external circuit board
66 due to uneven contraction of the
bonding agent
67 by cold.
FIG. 12 shows an IC chip package
70 constructed according to the seventh
embodiment of the present invention. According to this embodiment, the IC chip
package
70 is comprised of a carrier
71, a chip
72, a chip
shield
73, bonding wires
74, and a protective member
75. The
main features of this embodiment are outlined hereinafter.
The carrier
71 is made of metal and formed of a plurality of contact leads
for carrying the chip
72 and electrically connecting the chip
72
to an external circuit board. The protective member
75 is molded from synthesized
resin, for example, epoxy resin or silicon resin.
*
