Title of Invention

METHOD FOR PACKAGING FLASH MEMORY CARDS AND STRUCTURE FOR THE SAME

Abstract A method for packaging flash memory cards, comprising the steps of: (a) placing a circuit board (4) of said flash memory card over a concave housing (211) of a bottom plate (2); (a) placing a top plate (3) on top of said bottom plate (2) to cover said circuit board (4) with only exposing electrical connection parts of said circuit board (4); and (c) forming a cover layer of same material with said bottom plate(2) on the circumference of said bottom plate (2) and said top plate(3) to form final shape of said flash memory card.
Full Text FIELD OF THE INVENTION
The present invention generally relates to a structure and a packaging method
for flash memory cards, and more specifically to a structure and a packaging method for
flash memory cards using insert molding.
BACKGROUND OF THE INVENTION
As the digital products, such as digital camera, mobile phones, PDA, aie
becoming popular, the consumer demands on the flash memory cards increase. The
current types of the flash memory cards include compact flash (CF), card, smart media
card (SMC), multimedia card (MMC), secure digital (SD) card, memory stick (MS) card,
and an even newer xD-picture card. As the capacity of the memory cards increases, the
cost of the loss also increases if the memory card is broken or damaged and the precious
data is lost. Therefore, the manufacturers aim to improve the structure of the memory
cards so that not only the capacity of the memory cards is improved, but also the strength
of the structure and the water-proof effect.
Conventional memory cards are packed in a two-piece structure. That is, two
pieces of thin plates sandwich the circuit board, and a high-frequency melting technique
is then used to glue the two plates together to form a memory card structure. The
drawback of this structure is that it is prone to breakage at the glued seam or creating
small leakage gaps for humidity damaging the enclosed circuit board after a large number
of repetitive insertions and ejections of the memory cards from the electronic devices. A
number of techniques, such as U.S. Patent Application No. 11/146,545, are proposed for

enhancing the structure. For further improvement, the present invention provides a
structure and a method for packaging memory cards.
While the application and the cited reference are both pertaining to flash
memory card packaging, the present application uses a bottom plate, a circuit
board and a top plate, and seals the top plates and the bottom plates, while the cited
case uses a circuit substrate and a case cover.
Because the elements used in forming the flash memory cards are different
in both cases, the method of forming the structure are also different even though
the final shape of the packaged flash memory cards may look alike.
An insert molding process is used to form the covering layer (i.e., the
sealing) in the present application, while the cited reference uses an injection
molding process to form the case.
SUMMARY OF THE INVENTION
The present invention has been made to overcome the aforementioned
drawback of conventional structure and packaging methods. The primary object of
the present invention is to provide a packaging structure that is cost-effective and
has high yield rate, and a method of forming the same. The structure includes a
covering layer that is made of a material used in the final insert molding to
uniformly form a thin layer encompassing the outer structure of the memory card.
This covering layer avoids the impact of the material on the circuit board during
the insert molding so that yield rate is high. In case of the defect, the structure can
be disassembled, and the circuit board can be re-used to reduce the cost.
Another object of the present invention is to provide a packaging structure
that is water-proof, and a method of forming of forming the same. As the covering
layer of the structure is formed by insert molding, the sealing effect is good and the
final structure is water-proof.
Yet another object of the present invention is to provide a structure that is
applicable to a wide range of memory cards, and a method of forming the same.
The structure of the present invention is applicable to any memory cards that
include a two-plate structure sandwiching a circuit board.

To achieve the above object, the present invention provides a method for
packaging flash memory cards, comprising the steps of: (a) placing a circuit board
(4) of said flash memory card over a concave housing (211) of a bottom plate (2);
placing a top plate on top of said bottom plate (2) to cover said circuit board (4)
with only exposing electrical connection parts of said circuit board; and forming a
cover layer of same material with said bottom plate (2) on the circumference of
said bottom plate (2) and said top plate (3) to form final shape of said flash
memory card.
Furthermore according to the present invention it is provided a structure for
flash memory cards, comprising: a bottom plate(2), with a concave housing; a
circuit board (4), placed inside said concave housing of said bottom plate(2); a top
plate(3), for covering said bottom plate(2) and said circuit board (4) with only
exposing electrical connection parts of said circuit board (4); and a covering layer,
made of same material as said bottom plate(2) and said top plate(3) on
circumference of said bottom plate(2) and said top plate(3), areas surrounding said
electrical connection parts, and seam between said circuit board (4) and said
bottom plate(2) and said top plate(3).
The foregoing and other objects, feature, aspects and advantages of the
present invention will become better understood from a careful reading of a
detailed description provided herein below with appropriate reference to the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention can be understood in more detail by reading the subsequent
detailed description in conjunction with the examples and reference made to the
accompanying drawings, wherein:
FIG. 1 shows a flowchart of a packaging method of the present invention;
FIG.2 shows a schematic view of an embodiment of packaging an SD memory card
according to the present invention;
FIG.3A shows a schematic view of the circuit board being sandwiched by the bottom
plate and the top plate before covering layer according to the present invention;
FIG.3B shows a cross-sectional view of FIG.3A

FIG. 4A shows a schematic view of the circuit board being sandwiched by the bottom
plate and the top plate after the covering layer according to the present invention;
FIG. 4B shows a cross-sectional view of FIG. 4A;
FIG. 5 shows a schematic view of another embodiment of the present invention;
FIG. 6A shows a schematic view of the circuit board being sandwiched by the bottom
plate and the top plate before the covering layer of FIG. 5;
FIG. 6B shows a schematic view of the circuit board being sandwiched by the bottom
plate and the top plate after the covering layer of FIG. 5; and
FIG. 7 shows a schematic view of yet another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a flowchart of the present invention, including the following
steps. Step 11 is to place a circuit board onto a bottom plate. The bottom plate includes a
concave to house the circuit board. The electrical connection part of the circuit board is
exposed for further electrical connection. Step 12 is to place a top plate on the circuit
board to cover the circuit board except the exposed electrical connection part. Finally,
step 13 is to use insert molding to form a covering layer to encompassing the seam where
the bottom plate meets the top plate, the surrounding area of the electrical connection part
of the circuit board while exposing the electrical connection part. The hardening of the
molding material will slightly melt and glue the top and bottom plates tightly to form a
water-proof seal and the final structure will have a monolithic appearance of a memory

card with the electrical connection part exposed for electrical connection.
FIG. 2 shows an embodiment of packaging an SD card according to the
present invention. However, the present invention is not limited to the application of SD
cards. Any other equivalent types of memory cards are also within the scope of the
present invention. As shown in FIG. 2, a bottom plate 2 and the top plate 3 are formed
with an injection molding process in advance. The top surface of bottom plate 2 includes
a concave 21. The shape of concave 21 matches the shape of a circuit board 4. Concave
21 further includes at least a deep housing cave 211 a plurality of shallow housing caves
212. Deep housing cave 211 is for housing a memory chip 41 on circuit board 4, and
shallow housing caves 212 are for housing other smaller chips 42 and solder points 43, 44
of circuit board 4. The shape of each shallow housing cave 212 should accommodate the
corresponding elements on circuit board 4. When circuit board 4 is placed onto bottom
plate 2, the circuitry and the solder points on circuit board 4 are not interfered. The other
side of circuit board 4 includes a plurality of electrical connection parts 45, so-called
gold-fingers, as shown in FIG. 3A. The total thickness of bottom plate 2 and top plate 3
is equal to the standard thickness of an SD card. As a covering layer is formed with the
material during the insert molding process to cover the seam of bottom plate 2 and top
plate 3, the size of bottom plate 2 should be slightly smaller than the standard size of SD
cards. Furthermore, the circumference of bottom plate 2 should include a slanted slope
22 on at least two sides, and the circumference of top plate 3 should include a slanted
slope 31 on at least two sides to increase the attachment during the gluing process. Top
plate 3 is shorter than bottom plate 2, so that when placed on bottom plate 2, electrical
connection parts 45 of circuit board 4 are exposed.

FIGS. 3A and 3B show a schematic view of the circuit board being
sandwiched by the bottom plate and the top plate before the covering layer according to
the present invention, which corresponds to the view after step 12 of FIG. 1. As shown in
FIGS. 3A and 3B, circuit board 4 has only the electrical connection parts exposed, and
top plate 3 covers both circuit board 4 and bottom plate 2. The purpose of top plate 3 is
to shoulder the pressure on circuit board 4 during the insert molding process to prevent
the damage to circuit board 4.
FIGS. 4A and 4B show a schematic view of the circuit board being
sandwiched by the bottom plate and the top plate after the covering layer according to the
present invention, which correspond to the view after step 13 of FIG. 1. As shown in
FIGS. 4A and 4B, a covering layer A is made of the same material used for bottom plate
2 and top plate 3. Therefore, after covering layer A is hardened, covering layer A will
form a tight seal with bottom plate 2 and top plate 3 In addition, slanted slopes 22 on
bottom plate 2 and slanted slopes 31 on top plate 3 also increase the strength of the
bonding. As shown, covering layer A covers the circumferences of bottom plate 2 and
top plate 3, and the surrounding of exposed electrical connection parts 45 of circuit board
4. The final appearance after forming covering layer A (step 13 of FIG. 1) is a complete
seal memory card with electrical connection parts exposed. Because an insert molding
process is used to form covering layer A, the seal at the seam of bottom plate 2 and top
plate 3 is water-proof.
In summary of the aforementioned embodiment, the structure of the present
invention includes a bottom plate, a circuit board, a top plate and a covering layer. The
bottom plate includes a concave for housing the circuit board, and the top plate covers the

bottom plate and the most of the circuit board so that only the electrical connection part
of the circuit board is exposed. Both the bottom plate and the top plate have a slanted
slope on at least two sides of their circumference. The covering layer is made of the
material used in the insert molding process to form a thin layer to cover both the bottom
plate and the top plate and the seam between the two plates. The covering layer covers
the slanted slopes of both plates to enhance the water-proof seal. The covering layer
gives the final structure a monolithic appearance so that the sealing is water-proof.
FIG. 5 shows a schematic view of another embodiment of the present
invention, in this embodiment, the shape of top plate 3 includes a protruding block 32.
The shape of protruding block 32 corresponds to the shape of concave 21 of bottom plate.
As shown in FIG. 6A, protruding block 32 of top plate 3 is inside concave 21 of bottom
plate 2 when top plate 3 is placed into bottom plate 2. The purpose of having protruding
block 3 fitting inside concave 21 is to ensure that top plate will not shift due to the impact
of material during the insert molding process. In addition, protruding block can also
prevent the leakage of the molding material into the seam of bottom plate 2 and top plate
3. This will improve the yield rate. FIG. 6B shows a cross-sectionaj view of the final
structure.
FIG. 7 shows a schematic view of yet another embodiment of the present
invention. In this embodiment, one side of bottom plate 2 is attached to one side of top
plate 3. The thickness of this attachment is very thin so that when top plate 3 covers
bottom plate 2, an insert molding process can still be applied to form a covering layer on
the attachment to form a memory card. The advantage of this embodiment is that bottom
plate 2 and top plate 3 are monolithic and the subsequent packaging process is easier and

Although the present invention has been described with reference to the
preferred embodiments, it will be understood that the invention is not limited to the
details described thereof. Various substitutions and modifications have been suggested in
the foregoing description, and others will occur to those of ordinary skill in the art.
Therefore, all such substitutions and modifications are intended to be embraced within
the scope of the invention as defined in the appended claims.

I CLAIM:
1. A method for packaging flash memory cards, comprising the steps
of:
(a) placing a circuit board (4) of said flash memory card over a concave
housing (211) of a bottom plate (2);
(b) placing a top plate (3) on top of said bottom plate (2) to cover said
circuit board (4) with only exposing electrical connection parts of said
circuit board (4); and
(c) forming a cover layer of same material with said bottom plate (2) on the
circumference of said bottom plate (2) and said top plate (3) to form
final shape of said flash memory card.
2. The method as claimed in claim 1, wherein said covering layer of said
step (c) covers circumference of said bottom plate (2) and said top plate
(3), area surrounding said electrical connection parts, and seam between
said circuit board (4) and said bottom plate (2) and top plate (3).
3. A packaging structure for flash memory cards, comprising:
a bottom plate (2), with a conclave housing;
a circuit board (4), place inside said concave housing of said bottom
plate (2);
a top plate (3), for covering said bottom plate (2) and said top plate (3)
on circumference of said bottom plate (2) and said top plate (3), area
surrounding said electrical connection parts, and seam between said
circuit board (4) and said bottom plate (2) and said top plate (3).
4. The packaging structure as claimed in claim 3, wherein said covering
layer is formed by an insert molding process.
5. The packaging structure as claimed in claim 3, wherein said concave
housing further comprises at least a large deep concave area and a
plurality of small shallow concave areas for matching shape of said
circuit board and housing said circuit board (4).
6. The packaging structure as claimed in claim 3, wherein said bottom .
plate (2) has a slanted slop on at least two sides of said circumference.

7. The packaging structure as claimed in claim 3, wherein said top plate
(3) has a slanted slop on at least two sides of said circumference.
8. The packaging structure as claimed in claim 3, wherein said top plate
(3) further comprises a protruding block to fit in said concave housing
of said bottom plate (2).
9. The packaging structure as claimed in claim 3, wherein one side bottom
plate (2) is attached to one side of said top plate (3), and said top plate
(3) covers said bottom plate (2) when folded along said attached side.

Documents:

01081-kol-2006 abstract.pdf

01081-kol-2006 claims.pdf

01081-kol-2006 correspondence others.pdf

01081-kol-2006 description(complete).pdf

01081-kol-2006 drawings.pdf

01081-kol-2006 form-1.pdf

01081-kol-2006 form-2.pdf

01081-kol-2006 form-3.pdf

01081-kol-2006 form-5.pdf

01081-kol-2006 g.p.a.pdf

01081-kol-2006 priority documents.pdf

01081-kol-2006-correspondence-1.1.pdf

01081-kol-2006-priority document-1.1.pdf

1081-KOL-2006-ABSTRACT 1.1.pdf

1081-KOL-2006-AMANDED CLAIMS.pdf

1081-KOL-2006-CANCELLED PAGES.pdf

1081-KOL-2006-CLAIMS 1.1.pdf

1081-KOL-2006-CORRESPONDENCE 1.1.pdf

1081-KOL-2006-CORRESPONDENCE 1.2.pdf

1081-kol-2006-correspondence-1.3.pdf

1081-KOL-2006-DESCRIPTION (COMPLETE) 1.1.pdf

1081-KOL-2006-DESCRIPTION (COMPLETE) 1.2.pdf

1081-KOL-2006-DRAWINGS 1.1.pdf

1081-kol-2006-examination report.pdf

1081-KOL-2006-FORM 1.1.1.pdf

1081-kol-2006-form 18.pdf

1081-KOL-2006-FORM 2 1.2.pdf

1081-KOL-2006-FORM 2.1.1.pdf

1081-KOL-2006-FORM 3 1.1.pdf

1081-kol-2006-form 3-1.2.pdf

1081-KOL-2006-FORM 5 1.1.pdf

1081-kol-2006-form 5-1.2.pdf

1081-kol-2006-granted-abstract.pdf

1081-kol-2006-granted-claims.pdf

1081-kol-2006-granted-description (complete).pdf

1081-kol-2006-granted-drawings.pdf

1081-kol-2006-granted-form 1.pdf

1081-kol-2006-granted-form 2.pdf

1081-kol-2006-granted-specification.pdf

1081-KOL-2006-OTHERS 1.1.pdf

1081-KOL-2006-OTHERS.pdf

1081-kol-2006-pa-1.1.pdf

1081-KOL-2006-PA.pdf

1081-kol-2006-priority document.pdf

1081-kol-2006-reply to examination report.pdf

1081-kol-2006-translated copy of priority document.pdf

abstract-01081-kol-2006.jpg


Patent Number 248085
Indian Patent Application Number 1081/KOL/2006
PG Journal Number 24/2011
Publication Date 17-Jun-2011
Grant Date 15-Jun-2011
Date of Filing 17-Oct-2006
Name of Patentee LIU, CHIN-TONG
Applicant Address NO. 20, LANE 496, NOUPU SOUTH ROAD, HSINCHU
Inventors:
# Inventor's Name Inventor's Address
1 LIU, CHIN-TONG NO. 20, LANE 496, NOUPU SOUTH ROAD, HSINCHU
PCT International Classification Number G06K 9/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 094146117 2005-12-23 Taiwan