Active solid-state devices (e.g. – transistors – solid-state diode – Responsive to non-electrical signal
Reexamination Certificate
2003-06-25
2004-07-20
Ngô, Ngân V. (Department: 2814)
Active solid-state devices (e.g., transistors, solid-state diode
Responsive to non-electrical signal
C257S672000, C257S676000, C257S680000
Reexamination Certificate
active
06765274
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is base on Japanese priority application No. 2002-201384 filed Jul. 10, 2002, the entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to semiconductor devices and, more particularly, to a semiconductor device having a built-in contact-type sensor such as a fingerprint sensor and a manufacturing method of such a semiconductor device.
While electronic information communication spreads, the demand for individual identification has increased in electric equipment so as to observe the confidentiality of personal information. Although various technologies as means for personal identification have been developed and put into practical use, the technology for distinguishing a fingerprint has attracted attention. A semiconductor device in which a contact-type sensor using electric capacitance is incorporated as a small device for distinguishing a fingerprint has been developed.
2. Description of the Related Art
Generally, a fingerprint sensor referred to as a capacitance-type recognizes a fingerprint based on a change in the capacitance that is generated by bringing a finger tip into direct contact with a sensor surface. The fingerprint sensor called a sweep-type reads a fingerprint image by a sensor surface being swept by a finger. For example, a fingerprint image can be recognized by sensor surface being swept by a finger even if the sensor surface has a width as small as 1 mm. For this reason, the sweep-type fingerprint sensor is a mainline among fingerprint sensors that can be incorporated into portable equipment.
The electric-capacitance sensor used as a fingerprint sensor can be formed on a silicon substrate like a semiconductor element. That is, a fingerprint sensor can be produced as a part of a semiconductor chip that is formed of a silicon substrate.
FIG. 1
is a cross-sectional view of a semiconductor device having a built-in sweep-type fingerprint sensor in a state in which the semiconductor device is incorporated in a housing of an electronic device. In
FIG. 1
, bumps
1
c
of the semiconductor device
1
having a built-in fingerprint sensor is connected to a flexible board
2
through an anisotropically conductive resin
4
.
The semiconductor chip
1
is incorporated in a housing
3
of an electric device in a state in which a fingerprint sensor area
1
b
is exposed on a circuit formation surface
1
a
. That is, the fingerprint sensor area
1
b
is exposed to outside since it is necessary to move a finger while the finger is brought into contact with the fingerprint sensor area
1
b.
Since the fingerprint sensor area
1
b
is generally formed in the circuit formation surface
1
a
of the semiconductor chip
1
, the fingerprint sensor area
1
b
is provided on the same surface as a surface on which the bumps
1
c
, which serve as terminals for mounting the semiconductor chip
1
to the flexible board
2
, are provided. In the case of the example shown in
FIG. 1
, the bumps
1
c
that are protrudingly formed on the circuit formation surface
1
a
of the semiconductor chip
1
are connected and fixed to electrode pads
4
a
formed in the pattern wiring
4
of the flexible board
2
by an anisotropically conductive resin
5
.
In the structure shown in
FIG. 1
, the fingerprint sensor area
1
b
of the semiconductor chip
1
is a part, which is directly contacted by a finger, and must be exposed outside of the housing
3
of the electric device to be incorporated.
As mentioned above, since the fingerprint sensor area
1
b
is a part, which is directly contacted by a finger, there may be a case in which a finger cannot be completely brought into contact with the fingerprint sensor area if the peripheral portion of the exposed part is high. Particularly in the case of a fingerprint sensor device of the sweep-type, the width (X direction of
FIG. 1
) of the fingerprint sensor area
1
b
is as small as about 1 mm, a finger may not contact sufficiently if the peripheral portion is high. Therefore, the end of the flexible board
2
is not covered by the housing
3
, thereby being exposed to outside of the housing
3
.
When the end of the flexible board
2
is exposed, an external force may be exerted on the end of the flexible board
2
. For example, when moving a finger in an opposite direction (a direction opposite to the direction X), a force may be exerted on the end of the flexible board
2
which may cause the end of the flexible board to move upward. The end of the flexible board
2
is the connection portion to which the semiconductor chip
1
is connected, and, thus, if an upward force is exerted on the end of the flexible board
2
, the end of the flexible board
2
may be separated from the semiconductor chip
1
if the bonding force of the anisotropically conductive resin
5
is small. In this case, the electric connection between the semiconductor chip
1
and the flexible board
2
is deteriorated, which may cause a problem that the fingerprint sensor does not function well.
SUMMARY OF THE INVENTION
It is a general object of the present invention to provide an improved and useful semiconductor device having a built-in contact-type sensor in which the above-mentioned problems are eliminated.
A more specific object of the present invention is to provide a semiconductor device having a built-in contact-type sensor in which a connection portion between a semiconductor element and a wiring board is protected.
In order to achieve the above-mentioned invention, there is provided according to one aspect of the present invention a semiconductor device having a built-in contact-type sensor, comprising: a semiconductor element including a built-in contact-type sensor having a sensor area formed on a circuit formation surface and connection terminals provided in an area other than the sensor area; a wiring board connected to the connection terminals of the semiconductor element so that an end surface of the wiring board is positioned on the circuit formation surface; and a protective resin part covering a part extending from the end surface of the wiring board to the circuit formation surface.
According to the present invention, the end of the wiring board is covered by the protective resin part, and is firmly fixed to the circuit formation surface of the semiconductor element. Thereby, the end of the wiring board is prevented from separating from the semiconductor element due to an external force, which prevents failure of the semiconductor device due to separation of the wiring board from the semiconductor element.
Additionally, there is provided according to another aspect of the present invention a semiconductor device having a built-in contact-type sensor, comprising: a semiconductor element including a built-in contact-type sensor having a sensor area formed on a circuit formation surface and connection terminals provided in an area other than the sensor area; a wiring board connected to the connection terminals of the semiconductor element so that an end surface of the wiring board is positioned on the circuit formation surface; and a resin filled between the wiring board and the semiconductor element and covering the end surface of the wiring board.
According to the above-mentioned invention, the end of the wiring board is covered by the resin filled between the wiring board and the semiconductor element, and is firmly fixed to the circuit formation surface of the semiconductor element. Thereby, the end of the wiring board is prevented from separating from the semiconductor element due to an external force, which prevents failure of the semiconductor device due to separation of the wiring board from the semiconductor element.
Additionally, there is provided according to another aspect of the present invention a semiconductor device having a built-in contact-type sensor, comprising: a semiconductor element including a built-in contact-type sensor having a sensor area formed on a circuit formation surfac
Fujitsu Limited
Ngo Ngan V.
Westerman Hattori Daniels & Adrian LLP
LandOfFree
Semiconductor device having a built-in contact-type sensor... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Semiconductor device having a built-in contact-type sensor..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor device having a built-in contact-type sensor... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3198663