JPH04215224A - Circuit breaking fuse for ic chip with redundant circuit - Google Patents

Abstract

PURPOSE:To cut a fuse or the like securely even if some error is generated in an irradiation position of a laser beam or the like by bending a circuit breaking fuse in an irradiation position of the laser beam. CONSTITUTION:A fuse 2a or 2b is bent, and a laser beam or the like is irradiated to the bent position 3a or 3b, and a failure circuit is replaced with a redundant circuit electrically to relieve the circuit. With this structure, even if an error is generated in the irradiation position of the laser beam or the like to the fuse in any one of the longitudinal direction or the cross direction, the fuse is cut securely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a circuit-breaking fuse provided in an IC chip for relieving a defective IC chip with a redundant circuit.

[Prior Art] Fig. 2 is a plan view showing a conventional circuit-breaking fuse provided in an IC chip to relieve a defect in an IC chip with a redundant circuit, and Fig. 3 is a cross-sectional view of the fuse. be.

In these figures, 1 is an IC chip with a redundant circuit (hereinafter simply referred to as an IC chip), 2a' and 2b' are fuses for circuit interruption, 3a and 3b are irradiation positions of laser beams, etc.
4 is an IC board.

Next, the operation will be explained.

If there is a defective circuit in the IC chip 1 that can be salvaged by replacing it with a redundant circuit, the fuse 2a' or fuse 2b' is cut by irradiating the irradiation positions 3a and 3b with a laser beam, etc., and the defective circuit is replaced with a redundant circuit. Relieve the problem by replacing the circuit electrically. Although not shown, the fuses 2a', 2b', etc. are connected to the IC chip 1.
electrically connected to the production circuit or redundant circuit.

[Problems to be Solved by the Invention] Since the conventional circuit-breaking fuse has the above-mentioned configuration, the irradiation positions 3a and 3b of the laser beam, etc. that should be irradiated to the fuse 2a' or the fuse 2b', etc. are the fuses. The problem is that even if an error occurs in either the vertical or horizontal direction with respect to fuse 2a' or fuse 2b', the fuse 2a' or fuse 2b', etc. cannot be reliably cut, and it may not be possible to replace it with a redundant circuit. There was a point.

This invention was made to solve the above-mentioned problems, and even if there is a slight error in the irradiation position of the laser beam, etc. that should be irradiated to the fuse, it is possible to reliably cut the fuse. The purpose of this invention is to obtain a circuit-breaking fuse for an IC chip with a redundant circuit.

[Means for Solving the Problems] A circuit-breaking fuse of an IC chip with a redundant circuit according to the present invention is provided by bending the circuit-breaking fuse at the irradiation position of a laser beam irradiated to cut the circuit-breaking fuse. The shape is similar to that of the original.

[Function] The circuit-breaking fuse of the present invention has a bent shape that reliably catches the laser beam that should be irradiated to the fuse, so that even if there is some error in the irradiation position of the laser beam, the fuse will not work. definitely cut.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing a circuit-breaking fuse of an IC chip with a redundant circuit. In this figure, 2a and 2b are fuses for circuit breakage, and in this embodiment, even if the irradiation positions 3a and 3b of the laser beam etc. shift due to an error in either the vertical or horizontal direction, this can be detected reliably. The figure shows an example of a bent shape, for example, a shape bent at a right angle.

Note that the other details are the same as in FIGS. 2 and 3.

Next, the operation will be explained.

If there is a defective circuit in IC chip 1 that can be repaired by replacing it with a redundant circuit, fuse 2a or fuse 2
b by irradiating the irradiation positions 3a, 3b with a laser beam or the like to cut the defective circuit and electrically replace the defective circuit with a redundant circuit to save the defective circuit.

As shown in FIG. 1, fuse 2a or fuse 2b
By making the shape curved so that it can reliably catch a laser beam, etc., the success rate of cutting a fuse by irradiation with a laser beam, etc. is greatly improved.

Note that in the above embodiment, the fuse 2a or the fuse 2b
The case where one irradiation position 3a, 3b for irradiating the laser beam, etc. to the fuse 2a or 2b, etc. is shown, but these may be set separately in the vertical or horizontal straight parts of the fuse 2a or 2b, etc. .

[Effects of the Invention] As explained above, according to the present invention, the shape of the circuit-breaking fuse is bent at the irradiation position of the laser beam, so that the irradiation position of the fuse, such as the laser beam, is vertical or horizontal. Even if an error occurs in either direction, the fuse can be reliably blown and appropriate measures can be taken.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a circuit-breaking fuse for an IC chip with a redundant circuit according to an embodiment of the present invention, FIG. 2 is a plan view of a conventional fuse, and FIG. 3 is an enlarged sectional view of the fuse. In the figure, 1 is an IC chip with a redundant circuit, 2a and 2b are fuses for circuit interruption, 3a and 3b are irradiation positions for laser beams, etc., and 4 is an IC board. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Masuo Oiwa (2 others)

Claims (1)

[Claims] A circuit-breaking fuse provided in an IC chip for relieving a defect in an IC chip with a redundant circuit, characterized in that the circuit-breaking fuse has a shape bent at a laser beam irradiation position. Fuse for interrupting IC chip circuits.