Active solid-state devices (e.g. – transistors – solid-state diode – Lead frame – With structure for mounting semiconductor chip to lead frame
Reexamination Certificate
1997-10-22
2001-03-06
Chaudhuri, Olik (Department: 2814)
Active solid-state devices (e.g., transistors, solid-state diode
Lead frame
With structure for mounting semiconductor chip to lead frame
C257S673000, C257S680000, C257S686000, C257S696000, C257S730000, C257S773000
Reexamination Certificate
active
06198160
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor device, an appliance on which the semiconductor device is mounted, and a method of producing the semiconductor device.
The demand for minimizing the size or thickness of semiconductor devices, including semiconductor integrated circuit chips, has sharply increased, particularly in IC packaging. A chip scale package technique (CSP) is known for producing IC packages, namely semiconductor packaged IC chips for use as memories, which are reduced to a size almost equal to the size of an IC element. One such CSP technique is disclosed in Japanese Patent Laid-open Publication No. H8-125066.
FIG. 8
is a cross-sectional view of a conventional chip scale package, in which a semiconductor element
1
has pads
2
mounted on a center region of the lower side thereof. A connector lead frame
4
is located and bonded by an electrically insulating adhesive
3
to the lower side of the semiconductor element
1
. The connector lead frame
4
is connected by wires
5
to the pads
2
of the semiconductor element
1
. The connector lead frame
4
has projections formed by e.g. etching. The entire assembly is sealed with a resin material
6
, except for the projections of the lead frame
4
, which must be exposed. The exposed projections of the connector lead frame
4
are coated with doses of solder paste which serve as external electrodes
7
. The chip scale package is now completed.
However, such a conventional semiconductor device has some disadvantages. For example, forming of the connector lead frame by etching is an intricate task which is difficult to implement by a common pressing technique such as stamping as would serve to bring costs down. Also, sealing with resin is difficult since a particular region has to be exposed. This leads to deficiencies in technical quality.
SUMMARY OF THE INVENTION
The present invention is directed towards overcoming the above disadvantages attributed to conventional technology, and its primary object is to provide a novel, improved semiconductor device of surface-mount type which is simple in structure and capable of high-density mounting, to provide an appliance on which the semiconductor device is mounted, and to provide a method of producing the semiconductor device.
It is another object of the present invention to provide a novel, improved semiconductor device of surface-mount type in which patterns are formed on a circuit strip by a printed circuit board technique, thus to have a circuitry arrangement of higher accuracy and elaborateness and contributing to the ability to provide high-density mounting, an appliance on which the semiconductor device is mounted, and a method of producing the semiconductor device.
It is a further object of the present invention to provide a novel, improved semiconductor device of surface-mount type in which a circuit strip is equipped with ribs which serve as barriers to prevent overflow of a fluid resin material, thus permitting the procedure to be minimized and avoiding deflection of a region of the circuit strip provided for bonding to a semiconductor element, thereby to give a higher bonding strength, and also to provide an appliance on which the semiconductor device is mounted and a method of producing the semiconductor device.
It is a still further object of the present invention to provide a novel, improved semiconductor device of surface-mount type, an appliance on which the semiconductor device is mounted, and a method of producing the semiconductor device, wherein the semiconductor element is wrapped with both side ends of a circuit strip, thus increasing the mechanical strength even after mounted on a circuit board and ensuring a higher reliability, and in addition, with the circuit strip that wraps around the semiconductor element being made of a metallic material, obtaining a shielding effect, thus improving the electrical characteristics.
It is a still further object of the present invention to provide a novel, improved semiconductor device of surface-mount type which is matched to reflow conditions required for mounting on a circuit board and allows patterns on a circuit strip to be used for inspecting the electrical conduction after completed or mounted, an appliance on which the semiconductor device is mounted, and a method of producing the semiconductor device.
It is a still further object of the present invention to provide a novel, improved semiconductor device of surface-mount type which is tailored for providing a “towering arrangement, ” that is an arrangement in which two or more devices are mounted one over the other, thus permitting their processing capability to be optimized without increasing the mounting area on a circuit board, an appliance on which the semiconductor devices are mounted, and a method of producing the semiconductor devices.
For achievement of these objects, a semiconductor device or a method of producing the same embodying a first feature of the present invention is characterized by a circuit strip tailored to have its patterns projected, a semiconductor element fixedly joined to the circuit strip, and pads on the semiconductor element electrically connected by respective wires to the corresponding patterns on the circuit strip and sealed with a resin material.
A semiconductor device mounted appliance embodying a second feature of the present invention is designed in which the semiconductor device of the first feature is mounted on a circuit board.
A semiconductor device embodying a third feature of the present invention is characterized by a semiconductor element having electrodes provided on one side thereof, a circuit strip having conductive patterns provided on one side thereof, the other side of which being bonded to the semiconductor element, for corresponding to the electrodes which are exposed, wires respectively electrically joining between the electrodes and the conductive patterns, and a sealing material sealing the electrodes and the wires.
REFERENCES:
patent: 3930115 (1975-12-01), Uden et al.
patent: 4147889 (1979-04-01), Andrews et al.
patent: 4155615 (1979-05-01), Zimmerman, Jr. et al.
patent: 4398235 (1983-08-01), Lutz et al.
patent: 4673967 (1987-06-01), Hingorany
patent: 4996587 (1991-02-01), Hinrichmeyer et al.
patent: 5053852 (1991-10-01), Biswas et al.
patent: 5157475 (1992-10-01), Yamaguchi
patent: 5200364 (1993-04-01), Loh
patent: 5293068 (1994-03-01), Kohno et al.
patent: 5347159 (1994-09-01), Khandros et al.
patent: 5349501 (1994-09-01), Kawakami
patent: 5350947 (1994-09-01), Takekawa et al.
patent: 5359224 (1994-10-01), Heinen et al.
patent: 5375041 (1994-12-01), McMahon
patent: 5466888 (1995-11-01), Beng et al.
patent: 5583375 (1996-12-01), Tsubosaki et al.
patent: 5594275 (1997-01-01), Kwon et al.
patent: 5600179 (1997-02-01), Suzuki
patent: 5639990 (1997-06-01), Nishihara et al.
patent: 5674785 (1997-10-01), Akram et al.
patent: 5708293 (1998-01-01), Ochi et al.
patent: 5714405 (1998-02-01), Tsubosaki et al.
patent: 5747874 (1998-05-01), Seki et al.
patent: 5763829 (1998-06-01), Tomita et al.
patent: 5783857 (1998-07-01), Ziegner et al.
patent: 5801439 (1998-09-01), Fujisawa et al.
patent: 94 17 734 (1995-03-01), None
patent: 6-14219A1 (1994-09-01), None
patent: 8-125066 (1996-05-01), None
Chambliss Alonzo
Chaudhuri Olik
OKI Electric Industry Co., Ltd.
Rabin & Champagne, P.C.
LandOfFree
Surface mounted type semiconductor device with wrap-around... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Surface mounted type semiconductor device with wrap-around..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Surface mounted type semiconductor device with wrap-around... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2451787