Semiconductor device manufacturing: process – Packaging or treatment of packaged semiconductor – Including adhesive bonding step
Reexamination Certificate
2000-06-02
2003-05-13
Cuneo, Kamand (Department: 2829)
Semiconductor device manufacturing: process
Packaging or treatment of packaged semiconductor
Including adhesive bonding step
C438S106000
Reexamination Certificate
active
06562659
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a method for packaging an external circuit of a substrate provided with an amorphous semiconductor layer, for example, a two-dimensional image detector for detecting an electromagnetic wave image including radiation such as an X-ray, a visible ray, and an infrared ray, and the present invention further concerns a thermocompression bonding apparatus used for the method.
BACKGROUND OF THE INVENTION
Conventionally, a two-dimensional image detector for radiation has been known, in which semiconductor sensors for generating electrical charge (electron-hole pair) by detecting an X-ray, namely, semiconductor sensors constituted by semiconductor layers, pixel electrodes and others with photoconductivity are two-dimensionally disposed (row and column directions), each pixel electrode is provided with a switching element, the switching elements are successively turned on for each row, and electrical charge of the sensors is read for each column.
A specific construction and principle of such a two-dimensional image detector are described in “D. L. Lee, et al., ‘A New Digital Detector for Projection Radiography’, SPIE, 2432, pp. 237-249, 1995”, “L. S. Jeromin, et al., ‘Application of a-Si Active-Matrix Technology in a X-ray Detector Panel’, SID 97 DIGEST, pp. 91-94, 1997”, and Japanese Laid-Open Patent Publication No. 342098/1994 (Tokukaihei 6-342098, published on Dec. 13, 1994).
The following explanation discusses the construction and principle of a conventional two-dimensional image detector for radiation.
FIG. 11
is a schematic diagram showing the construction of the conventional two-dimensional image detector for radiation. Further,
FIG. 12
is a schematic diagram showing a sectional structure for one pixel of the two-dimensional image detector for radiation.
As shown in
FIGS. 11 and 12
, the two-dimensional image detector for radiation is provided with an active-matrix substrate
56
. Electrode wires (a gate electrode group
64
composed of gate electrodes G
1
, G
2
, G
3
, . . . , Gn, and a source electrode group
65
composed of source electrodes S
1
, S
2
, S
3
, . . . , Sn) in an XY matrix form, a TFT (thin film transistor)
69
, and a storage capacitor(Cs)
70
, and others are formed on virtually the entire surface of the active-matrix substrate
56
. Input/output terminals are formed on a surrounding part (not shown) of the active-matrix substrate
56
. Further, a photoconductive film
52
, a dielectric layer
68
, and an upper electrode
66
are formed on virtually the entire surface of the active-matrix substrate
56
.
The storage capacitor
70
has a construction in which a Cs electrode
74
is opposed via an insulating film
73
to a pixel electrode
72
connected to a drain electrode of the TFT
69
.
As the photoconductive film
52
(amorphous semiconductor layer), a semiconducting material is used, which generates electrical charge (electron-hole pair) by exposure to radiation such as an X-ray. According to the aforementioned literatures, it is possible to adopt an organic substance such as a photoconductive polymer, which exerts photoconductivity by adding an X-ray absorbing compound, as well as amorphous-selenium (hereinafter, referred to as a-Se), lead monoxide, cadmium sulfide, and mercuric iodide. The photoconductive film
52
is formed with, for example, a thickness of 300 to 600 &mgr;m by using a vacuum evaporation method.
Further, an active-matrix substrate formed in a manufacturing process of a liquid crystal display device can be applicable as the active-matrix substrate
56
. For example, the active-matrix substrate used for an active-matrix liquid crystal display device (AMLCD: Active Matrix LCD) is provided with a TFT made of a material such as amorphous silicon(a-Si) and polysilicon(p-Si), an XY matrix electrode, and a storage capacitor. Therefore, only a few changes in arrangement allows the active-matrix substrate to be adopted for the two-dimensional image detector for radiation.
The following explanation describes a principle of operations of the two-dimensional image detector for radiation having the above construction.
When radiation is emitted to the photoconductive film
52
, electrical charge (electron-hole pair) is generated in the photoconductive film
52
. As shown
FIGS. 11 and 12
, the photoconductive film
52
and the storage capacitors
70
are electrically connected in series. Thus, when voltage is applied between the upper electrode
66
and the Cs electrode
74
in the two-dimensional image detector for radiation, electrical charge (electron-hole pair) generated in the photoconductive film
52
moves to a positive electrode side and a negative electrode side. As a result, the storage capacitors
70
store electrical charge. Further, a carrier blocking layer
71
composed of a thin insulating layer is formed between the photoconductive film
52
and the storage capacitors
70
. The carrier blocking layer
71
prevents electrical charge from being injected from only one of the photoconductive film
52
and the storage capacitors
70
.
With the above-mentioned effect, the TFTs
69
come into an open state in response to input signals of gate electrodes G
1
, G
2
, G
3
, . . . , Gn, so that the electrical charge stored in the storage capacitors
70
can be applied from the source electrodes S
1
, S
2
, S
3
, . . . , Sn to the outside. The electrode group
64
including the gate electrodes G
1
, G
2
, G
3
, . . . , Gn, the source electrode group
65
including the source electrodes S
1
, S
2
, S
3
, . . . , Sn, the TFTs
69
, and the storage capacitors
70
and others are formed in a XY matrix form. Therefore, it is possible to obtain two-dimensional image information of an X-ray by successively scanning signals inputted to gate electrodes G
1
, G
2
, G
3
, . . . , Gn, for each of the gate electrodes.
The above two-dimensional image detector is provided with a “driving circuit” (driving IC) for supplying driving voltage of a switching element (TFT) to the gate electrode group
64
and the source electrode group
65
, and a “reading circuit” (reading IC) for reading image information, on the surrounding part of the active-matrix substrate
56
. These circuits are packaged mainly in line with TCP (Tape Carrier Package) method and COG (Chip on Glass) method.
FIG.
13
(
a
) shows an example of a conventional packaging according to TCP method. In TCP method, a wiring pattern made of aluminum foil is formed on a TCP substrate
59
including a base film made of a material such as polyimide, one end of an external circuit, on which electrical members such as a driving IC
60
and an IC
61
are mounted, is connected to a surrounding area of the active-matrix substrate
56
constituting the two-dimensional image detector for radiation, and the other end of the circuit is connected to an external circuit substrate (PWB: Printed Wiring Board)
62
.
Further, FIG.
13
(
b
) shows an example of a conventional packaging according to COG method. In COG method, the driving IC
60
and the reading IC
61
are mounted and connected as external circuits directly to the input/output terminals of the active-matrix substrate
56
constituting the two-dimensional image detector for radiation. Here, power supply and the input and output of signals are carried out by an FPC (Flexible Printed Circuit) substrate
67
. One end of the FPC substrate
67
is connected to the input/output terminals (not shown) of the surrounding part on the active-matrix substrate
56
constituting the two-dimensional image detector, the end is electrically connected to the driving IC
60
and the reading IC
61
via the gate electrodes G
1
, G
2
, G
3
, . . . , Gn (gate electrode group
64
) and the source electrodes S
1
, S
2
, S
3
, . . . , Sn (source electrode group
65
) of the active-matrix substrate
56
, and the other end of the FPC substrate
67
is connected to the external circuit substrate
62
. As a variation of COG method, the driving IC
60
and the reading IC
61
can be formed in a monolithic manner upon manufacturing
Izumi Yoshihiro
Teranuma Osamu
Cuneo Kamand
Geyer Scott B.
Nixon & Vanderhye PC
Sharp Kabushiki Kaisha
LandOfFree
External circuit packaging method and thermocompression... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with External circuit packaging method and thermocompression..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and External circuit packaging method and thermocompression... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3023744