JPH0223599A - Redundancy system for semiconductor device - Google Patents

Abstract

PURPOSE:To make the distance between a fault bit and normal bit larger by relieving the adjacent bit line pairs of the bit line pair in which the faulty bit occurs. CONSTITUTION:When a faulty point A occurs in a bit line pair B and the inverse of B connected with a sense amplifier, the adjacent bit line pairs B and the inverse of B on both sides of the faulty bit line pairs B and the inverse of B in which the faulty point A occurs are relived together with the faulty bit line pairs B and the inverse of B. Therefore, the distances between the faulty bit line B and the inverse of B and normal bit line pairs B and the inverse of B become larger and adverse influences from the faulty bit line pair B and the inverse of B to the normal bit line pairs B and the inverse of B can be reduced.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a redundancy system for semiconductor devices.

[Conventional technology]

FIG. 2 is a diagram showing a conventional redundancy system for semiconductor devices.

Point A in this figure, so to speak, when a failure occurs in a certain bit line pair, only that bit line pair is repaired.

[Problem to be solved by the invention]

As mentioned above, in order to repair only 9 bit line pairs due to failure in the conventional redundancy system, especially in highly integrated semiconductor devices (the distance between bit lines is short),
The influence of defective bits on normal bits can no longer be ignored.

A specific example is shown in FIG. If a leak occurs in a certain bit line (the point shown by the person in the figure), even if the defective bit line pair is redundant, the adjacent bit line will be affected. As a result, the pattern dependence changes as shown in Figure 1. If a leak occurs at point A (Bs) and what should be a high level changes to a low level, BS will help the low level of 101, and the effect on the high level B3 will be more severe than before. In this way, in the conventional semiconductor device redundancy system,
It is quite conceivable that the pattern dependence will change.

In order to solve this problem, the present invention employs a redundancy method that also replaces the bit line pairs on either side of the defective bit line pair, thereby reducing the distance between the defective bit ring and the normal bit line next to it. [Means for Solving the Problem] The redundancy method according to the present invention is designed to provide a redundancy system for semiconductor devices that can ignore such effects.
The bit a pair on both sides of the pair is also rescued.

[Effect]

In this invention, the distance between the defective bit and the normal bit can be increased by changing the weight of the bit line pairs on either side of the nine bit line pair when a defect occurs.

The influence of defective bits on normal bits can now be ignored.

C Implementation Column] FIG. 1 is a diagram showing the redundancy system of the present invention. In the diagram, is there a defect at point A? In this case, by repairing both bit line pairs, the distance to the normal bit is increased and the distance from the defective bit is reduced.

〔Effect of the invention〕

As explained above, this invention can also repair bit lines on either side of a defective bit line pair.
The influence of defective bits on normal bits can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a redundancy system of a semiconductor device according to an embodiment of the present invention, FIG. 2 is a diagram showing a conventional redundancy system of a semiconductor device, and FIG. 8 is a diagram showing problems of the conventional redundancy system of a semiconductor device. FIG.

Claims (1)

[Claims] A redundancy system for a semiconductor device characterized by repairing bit lines on both sides of a bit line pair in which a defect has occurred.