Active solid-state devices (e.g. – transistors – solid-state diode – Responsive to non-electrical signal – Electromagnetic or particle radiation
Reexamination Certificate
2002-03-19
2003-10-21
Nelms, David (Department: 2818)
Active solid-state devices (e.g., transistors, solid-state diode
Responsive to non-electrical signal
Electromagnetic or particle radiation
C257S431000, C257S432000, C257S433000
Reexamination Certificate
active
06635941
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor device and its manufacture method, and more particularly to a semiconductor device having photoelectric conversion elements and its manufacture method.
2. Related Background Art
A conventional image pickup module has a semiconductor chip with light reception elements and a substrate having lenses for converging light on the light reception elements. The semiconductor chip and substrate are mounted on both sides of a spacer to be spaced apart by some distance. Light can be converged on a light reception plane of each light reception element so that a real image can be formed.
FIGS. 18A
,
18
B and
18
C are broken perspective views illustrating a conventional image pickup module manufacture method.
FIG. 18A
shows a substrate
917
having lenses for converging light on a light reception element,
FIG. 18B
shows a spacer
901
, and
FIG. 18C
shows a semiconductor chip
503
having light reception elements
100
. According to a conventional image pickup module manufacture method, the substrate
917
and semiconductor chip
503
are bonded on both sides of the spacer
901
to form an image pickup module. If each of a plurality of image pickup modules is manufactured by this method, a number of manufacture processes are required including an alignment process for the semiconductor chip
503
and substrate
917
.
FIGS. 19A
,
19
B and
19
C are schematic cross sectional views illustrating another conventional image pickup module manufacture method.
FIG. 19A
is a schematic cross sectional view of a semiconductor wafer
910
formed with a plurality of semiconductor chips, the wafer having some warp caused by a passivation film or the like formed by a semiconductor device manufacture process. This warp has a height difference of, for example, about 0.2 mm between the highest and lowest positions in the case of an 8-inch wafer. A wafer with a warp has a roll shape, a saddle shape, a bowl shape or the like.
As shown in
FIG. 19B
, the warp of the semiconductor wafer
910
is removed by sucking the bottom surface of the wafer
910
by using a jig
950
.
Next, as shown in
FIG. 19C
, the semiconductor wafer
910
and a substrate
917
are bonded together via a spacer
901
.
Thereafter, suction of the semiconductor wafer
910
is released to dismount the semiconductor wafer
910
and lens substrate
917
from the jig
950
. This assembly of the semiconductor wafer and lens substrate is cut along each semiconductor chip and lens to form an image pickup module. A method of bonding together the semiconductor wafer
910
with semiconductor chips and the substrate
917
by a single alignment process is suitable for the manufacture of a plurality of image pickup modules.
(First Technical Issue)
After the semiconductor wafer
910
is bonded via the spacer
901
to the lens substrate
917
having a plurality of lenses for diverging light on light reception elements, each image pickup module is formed by dicing the substrate along each scribe line between semiconductor chips. During dicing, a force is applied to the substrate
917
from a dicing blade. This force may change the surface shape of a lens and hence a reflectivity thereof, degrading a focussing performance.
It is therefore an object of the invention to efficiently manufacture a semiconductor device such as an image pickup module without changing the surface shape of a lens during dicing.
(Second Technical Issue)
With the manufacture method illustrated in
FIGS. 19A
to
19
C, after suction of the semiconductor wafer
910
is released, the semiconductor wafer
910
tends to recover the original warp state. If the lens substrate
917
is bonded to the semiconductor wafer
910
with a warp on the convex surface side, the semiconductor wafer
910
and lens substrate
917
are likely to be peeled off in the peripheral area of the semiconductor wafer
910
.
Conversely, if the lens substrate
917
is bonded to the semiconductor wafer
910
with a warp on the concave surface side, the semiconductor wafer
910
and lens substrate
917
are likely to be peeled off in the central area of the semiconductor wafer
910
.
If the semiconductor wafer
910
and lens substrate
917
are peeled off at the worst, or if an adhesive layer between the semiconductor wafer
910
and lens substrate
917
is elongated, the distance between the semiconductor wafer
910
and lens substrate
917
changes so that light cannot be converged correctly on the light reception element, disabling desired image pickup in some cases.
It is therefore another object of the invention to manufacture a semiconductor device such as an image pickup module capable of realizing reliable image pickup by considering a warp of a semiconductor substrate such as the semiconductor wafer
910
.
SUMMARY OF THE INVENTION
According to one aspect of the invention, there is provided a semiconductor device formed by cutting a first substrate and a second substrate bonded together by a spacer, wherein: the spacer is disposed at an end of the first substrate after cutting; the second substrate is a semiconductor wafer formed with a light reception element or elements; and the first substrate has an optical element or an optical element set for converging light on the light reception element or elements.
According to another aspect of the present invention, there is provided a semiconductor device manufacture method comprising: a step of bonding a first substrate and a second substrate by using a spacer; and a step of cutting the first and second substrates, wherein the step of cutting the first substrate cuts the first substrate at a position where the spacer is disposed under the first substrate.
According to still another aspect of the present invention, there is provided a semiconductor device manufacture method comprising: a step of holding the semiconductor substrate on a base under a condition that the warp is removed; a step of bonding an opposing substrate to the semiconductor substrates with a size adjusted according to the warp of the semiconductor substrate; and then a step of cutting the opposing substrate.
REFERENCES:
patent: 4375018 (1983-02-01), Petersen
patent: 4729640 (1988-03-01), Sakata
patent: 4824073 (1989-04-01), Zdeblick
patent: 4911968 (1990-03-01), Higasihara et al.
patent: 5146671 (1992-09-01), Ogawa et al.
patent: 5340978 (1994-08-01), Rostoker et al.
patent: 5629787 (1997-05-01), Tsubota et al.
patent: 5751492 (1998-05-01), Meyers
patent: 6122009 (2000-09-01), Ueda
patent: 6304243 (2001-10-01), Kondo et al.
patent: 2002/0062787 (2002-05-01), Hashizume et al.
patent: 1 067 779 (2001-01-01), None
patent: 9-27606 (1997-01-01), None
patent: 11-121653 (1999-04-01), None
patent: 11-142611 (1999-05-01), None
patent: 11-345785 (1999-12-01), None
patent: 2000-61677 (2000-02-01), None
patent: 2001-78213 (2001-03-01), None
patent: 2001-78217 (2001-03-01), None
LandOfFree
Structure of semiconductor device with improved reliability does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Structure of semiconductor device with improved reliability, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Structure of semiconductor device with improved reliability will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3134151