Semiconductor device

Details Semiconductor device Semiconductor device

2003-05-30

2004-11-23

Auduong, Gene N. (Department: 2818)

Static information storage and retrieval

Read/write circuit

Bad bit

C365S225700, C365S230060

Reexamination Certificate

active

06822912

ABSTRACT:

CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims priority of Japanese Patent Application No. 2002-190800, filed on Jun. 28, 2002, the contents being incorporated herein by reference.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to a semiconductor device and, more particularly, to a semiconductor device having a macro cell including a plurality of macro cells and a fuse, and a fuse.
(2) Description of the Related Art
For example, with semiconductor devices, such as memories, the following method has been adopted. A cell array is divided into a plurality of blocks. If one block does not work well, another block is used in place of this block. By adopting this method, yields can be raised.
FIG. 14
is a view showing an example of this conventional method.
In
FIG. 14
, a semiconductor device
10
comprises macro cells
10
a
through
10
d
, fuses
10
e
through
10
h
, and connection lines
10
i
through
10
l.
The macro cell
10
a
includes, for example, a cell array divided into a plurality of blocks. One of the blocks is a redundant block and the rest are normal blocks.
All of the fuses
10
e
through
10
h
have the same structure. Description will be given with the fuse
10
e
as an example. As shown in
FIG. 15
, the fuse
10
e
includes a pull-up resistor
20
, a connection section
21
, a fuse element group
22
, and a decoder
23
. If a predetermined normal block included in the macro cell
10
a
does not work well, the normal block to be replaced is specified by fusing a fuse element included in the fuse element group
22
into a predetermined pattern by the use of a laser beam.
Now, operation performed in the above conventional method will be described. Description will be given on the assumption that each of the macro cells
10
a
through
10
d
includes ten normal blocks and one redundant block.
It is assumed that a first normal block in the macro cell
10
a
does not work well, that a third normal block in the macro cell
10
c
does not work well, and that the remaining macro cells
10
b
and
10
d
are normal.
Then a fuse in the fuse
10
e
corresponding to the first normal block in the macro cell
10
a
is fused by the use of a laser beam and a fuse in the fuse
10
g
corresponding to the third normal block in the macro cell
10
c
is fused by the use of a laser beam.
As a result, in the fuse
10
e
output from the fuse fused goes into the “L” state and output from the other fuses goes into the “H” state. The decoder
23
decodes these signals output from the fuse element group
22
and supplies them to the macro cell
10
a.
In the macro cell
10
a
, the first normal block is replaced with a redundant block in response to a signal supplied from the decoder
23
in the fuse
10
e
. As a result, the first normal block is excepted and the redundant block is used instead. The macro cell
10
a
therefore can operate normally.
The same operation will be performed in the fuse
10
g
and macro cell
10
c
, so that the third normal block is replaced with a redundant block. The macro cell
10
c
therefore can operate normally.
The macro cells
10
b
and
10
d
are normal, so replacement will not be made.
By the way, in recent years the process for fabricating semiconductor devices has become minuter, so the size of the macro cells
10
a
through
10
d
tends to reduce. On the other hand, individual fuses in the fuses
10
e
through
10
h
must be located at moderate intervals because they must be fused selectively by the use of a laser beam. Therefore, though the size of the macro cells
10
a
through
10
d
is reduced by adopting a minute process, the size of the fuses
10
e
through
10
h
is not reduced. This is a bottleneck in reducing the entire size of the semiconductor device.
SUMMARY OF THE INVENTION
The present invention was made under the background circumstances as described above. An object of the present invention is to make it possible to reduce the size of a semiconductor device having a plurality of macro blocks and a fuse.
In order to achieve the above object, a semiconductor device comprising a plurality of macro cells each including a plurality of normal blocks each including circuits each having a predetermined function and a redundant block having the same function as the normal blocks have and used, in the case of one of the normal blocks not working well, in place of the normal block and a fuse shared by the plurality of macro cells for holding information for specifying the normal block to be replaced with the redundant block included in the macro cell is provided.
The above and other objects, features and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings which illustrate preferred embodiments of the present invention by way of example.


REFERENCES:
patent: 5208782 (1993-05-01), Sakuta et al.
patent: 6282145 (2001-08-01), Tran et al.
Japanese patent application publication No. 2000-114384, dated Apr. 21, 2000.

Affiliated with

Also associated with

Rating

Semiconductor device 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, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor device will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3297278