Semiconductor device and method for fabricating the same

A semiconductor device including a memory cell region where a plurality of memory cells are formed, and a fuse circuit region where a fuse circuit for replacing a defective memory cell by a redundant memory cell is formed, the semiconductor device comprising:

• a blocking layer formed in the fuse circuit region;
• an insulation film formed on the blocking layer;
• and
• a fuse formed on the insulation film and formed of the same conducting layer as a conducting layer forming the memory cells or an interconnection layer formed in the memory cell region,
• the blocking layer preventing the substrate from ablating when the fuse is disconnected by laser ablation.

A semiconductor device including a memory cell region where a plurality of memory cells are formed, and a fuse circuit region where a fuse circuit for replacing a defective memory cell by a redundant memory cell is formed, the semiconductor device comprising:

• a base semiconductor substrate;
• a layer or layers formed on the base semiconductor substrate;
• and
• a fuse formed on the layer or the layers in the fuse circuit region and formed of the same conducting layer as a conducting layer forming the memory cells or an interconnection layer formed in the memory cell region and disconnected by laser ablation,
• a thickness of the layer or the layers being much thicker than a thickness of the fuse,
• the layer or the layers preventing the base semiconductor substrate from ablating when the fuse is disconnected by laser ablation.

A laser system for disconnecting by laser ablation a fuse of the semiconductor device including a blocking layer formed on a substrate, an insulation film formed on the blocking layer and the fuse formed on the insulation film, the laser system comprising:

• a laser resonator for oscillating a laser beam having an oscillation wavelength of not more than 500 nm and an energy density sufficient to disconnect the fuse by laser ablation and not to ablate the blocking layer;
• a lens mechanism for condensing the laser beam emitted by the laser resonator into a required spot size;
• and
• an alignment mechanism for irradiating the laser beam outputted by the laser resonator to a required position on the semiconductor device.

A semiconductor device comprising:

• a blocking layer formed on a substrate;
• an insulation film formed on the blocking layer;
• and
• a fuse of a metal material formed on the insulation film,
• the blocking layer preventing the insulation film and/or the substrate from ablating when the fuse is disconnected by laser ablation.

A semiconductor device comprising:

• a blocking layer formed on a substrate, the blocking layer including a tungsten film;
• an insulation film formed on the blocking layer;
• and
• a fuse of a metal material formed on the insulation film,
• the blocking layer preventing the insulation film and/or the substrate from ablating when the fuse is disconnected by laser ablation.

A semiconductor device comprising:

• a first insulation film formed on a substrate;
• a blocking layer formed on the first insulation film, the blocking layer including a tungsten film;
• an second insulation film formed on the blocking layer;
• and
• a fuse of a metal material formed on the second insulation film,
• the blocking layer preventing the second insulation film and/or the substrate from ablating when the fuse is disconnected by laser ablation.