Electricity: electrical systems and devices – Housing or mounting assemblies with diverse electrical... – For electronic systems and devices
Reexamination Certificate
2002-07-23
2004-03-23
Gibson, Randy (Department: 2841)
Electricity: electrical systems and devices
Housing or mounting assemblies with diverse electrical...
For electronic systems and devices
C361S785000, C361S777000, C361S803000, C361S820000, C257S713000
Reexamination Certificate
active
06711025
ABSTRACT:
BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to the combination device of the IC connection device and the main board. Especially, the present invention relates to a main board which is suitable to combine one of the pin-style socket and the ball-style socket.
(b) Description of the Prior Arts
For long time in prior art, there are two basic methods to place IC package on main board. One is to solder firmly the IC package on the main board but the IC package is not replaceable. The other method is that the IC package is replaceable, so the IC package can be replaced when necessary. Most of time, the replaceable combination device of the IC connection device and the main board is used when the IC device needs to be upgraded, the IC device itself needs to be replaced or in some cases that need expensive IC device. The replaceable IC device is used when one of the devices on main board is broken or needs to be replaced but the rest of the components on the board still in good condition, the combination device of the main board and the socket of the CPU is a best example.
Please refer to FIG.
1
and
FIG. 2
, which showing a conventional replaceable combination device
10
of the main board and the socket of IC device in prior art. In prior art, an IC device
11
has pins
111
, and the main board
12
has a socket
13
with many pin holes
131
in order to connect each other in better electrical condition. There are two basic methods to seal down the IC device
11
, one is called lead frame and the other is BGA. In recent years, another method called flip chip BGA packaging has been used more often in sealing high-numbered pins IC package.
FIG. 1
shows the basic components which comprising an IC chip
112
placed on one side of the substrate
113
by flip chip method. Several solder balls
114
are placed on the other side of the substrate
113
, which connecting the IC chip
112
and the substrate
113
. The other side of the IC chip
112
has a heat sink
115
. For the pins
111
is not hard enough, and it is easy to be broken during replacing. And for the pins
111
is not easy to connect the solder
114
firmly. So, before being soldered to the solder ball
114
, it has to be placed on an interposer
116
with modeling technology.
In order to provide the function, the pins
111
of the IC device
11
will be placed. The socket
13
in prior art comprises a socket base
132
with a plurality of holes
131
soldered on the main board
12
, a sliding board
133
which can slide linearly and a long levering bar
134
placed aside the socket base
132
to be used to move the sliding board
133
in a micro manner. The electrically conducting pad
137
is placed in every pin hole
131
of the socket
132
. And the solder pad
135
is on the bottom part of the pin holes
131
. The pin holes
131
are extended from the bottom part of the electrically conducting pad
137
in order to form the PTH (Plated Through Hole)
121
in the main board
12
for pins
1371
. The electrically conducting layer
122
is set in the PTH
121
of the main board
12
in order to connect with pins
1371
electrically. The position of the contact pad
1221
and the PTH
121
on the upper surface of the main board
12
can be SMD (solder mask defined) or NSMD (none solder mask defined. The pins
1371
and the electrical connection device
13
are soldered on the main board
12
firmly by the materials
123
and
125
of the soldering. The larger holes on the sliding pad
133
corresponding to the pin holes
13
are set. Rotating the long stick
134
along the axle
136
to be parallel with the socket
132
will make the slider
133
move in micro manner and the pins
111
in IC package
11
be hold tightly in the pin holes
131
. In order to take out the IC package
11
, the long stick
134
can be rotated to be horizontal with the socket
132
, and then the pins
111
can be released from the IC package
11
.
Please refer to
FIG. 3
which is the combination device
10
a
of the main board and the electrical connection device of the replaceable IC package in prior art. Because the IC package
11
and the electrical connection device
13
a
in prior art are similar to the devices in prior art in
FIG. 1
, additional description of the detailed element and the structure is not necessary, but shown in dashed lines. The main difference in
FIG. 3
is that the combination device
10
a
is using several solder balls
138
but not the pin-style structures. Instead of PTH, the solder pad
126
is placed on the main board
12
a
by solder reflow of the solder ball
138
of the electrical connection device
13
a
and the solder pad
126
of the main board
12
a.
We can solder on the solder pad
126
firmly for the solder balls
138
. The disadvantages in prior art are the intensity of the structure of the combination of the solder balls
138
and the solder pad
126
is weaker because the solder balls
138
and the solder pad
126
combine in plane-contact style. The disadvantage will lead to the increase of the defect of the products. Or the department of the solder balls
138
from the solder pad
126
will be possible. And the stability of the electricity and the short-circuit characteristics will happen because the overflow of the solder balls
138
in the solder reflow. In the same time, the co-planarity of the combination of the electrical connection device
13
a
and the main board
12
a
will be bad.
The pin-style electrical connection device in
FIG. 1
in prior art and the ball-style electrical connection device
13
a
in
FIG. 3
in prior art will use the corresponding main board
12
and
12
a
. Because the main board
12
a
in
FIG. 3
will not provide the PTH to apply the usage of the pin-style electrical connection device
13
. The PTH
121
in the main board
12
can apply the usage of the pin-style electrical connection device
13
. The main board
12
with PTH
121
will be in solder reflow with the ball-style electrical connection device
13
a
according to the ratio of the Sn/Pb being 63/37 and the Eutectic temperature of the solder balls being 183 degrees. The working temperature is changed according to the different time period. The highest working temperature is 220 degrees. We can not provide the stable connection of the electricity and the function of the soldering firmly. So we will not find the both functions of the ball-style electrical connection device
13
a
and the pin-style connection device
13
which are applied to the same main board.
SUMMARY OF THE INVENTION
The primary aspect of the present invention is to provide the same combination device of the main board and the IC package connection device. We can apply the combination device to combine with one of the ball-style electrical connection device and the pin-style electrical connection device.
In another aspect of the present invention is to provide the combination device of the main board and the IC package connection device. By the way of changing the ratio of the Sn/Pb in solder balls on the bottom surface of the socket of the ball-style electrical connection device, the Liquidus temperature (totally melting temperature) of the solder balls will be changed to a proper value (higher than the Eutectic temperature). Thesemi-melting state of the solder balls will not be empty in the PTH in the solder reflow of the main board with PTH and the ball-style electrical connection device. A part of the semi-meltingsolder ball will be putted in a part of the PTH in order to make the solder ball be a mushroom-shape structure after the process of solder reflow to provide the good intensity of the structure of the combination, the co-planarity and the yield of the product.
To achieve the purposes described above, one of the embodiment of the present invention comprises a socket and a main board. Said socket includes the inputted assembly on the top surface of the socket being used to connect with the IC package electrically and some solder balls. The solder balls are on the bottom surface and are
Ho Kwun-Yao
Moriss Kung
Bui Hung
Gibson Randy
Via Technologies Inc.
LandOfFree
Combination device of the IC connection device and the main... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Combination device of the IC connection device and the main..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Combination device of the IC connection device and the main... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3273720