Semiconductor device and method for determining fuse state

A semiconductor device comprising:

• a semiconductor substrate;
• a fuse which comprises a conductive material and is formed on said semiconductor substrate;
• a contacting target conductor region which is placed around said fuse on said semiconductor substrate and formed so as to make electrical contact with the fuse through the conductive material constituting the fuse when a process for cutting the fuse is carried out;
• and
• a determination unit which detects whether or not said fuse is electrically disconnected, as well as whether or not said contacting target conductor region and said fuse are electrically connected, and determines that said fuse is in a cut state when electrical disconnection of said fuse is detected or electrical connection between said contacting target conductor region and said fuse is detected,
• wherein said determination unit includes:
• a first detection unit which is connected to one end of said fuse and detects whether or not the fuse is electrically disconnected;
• a second detection unit which is connected to said contacting target conductor region and detects whether or not said contacting target conductor region and said fuse are electrically connected;
• and
• an output unit into which an output from said first detecting unit and an output from said second detection unit are inputted, and which outputs a signal indicating that said fuse is in a cut state in the case where electrical disconnection of said fuse is detected by said first detection unit or in the case where electrical connection between said contacting target conductor region and said fuse is detected by said second detection unit, and
• wherein said second detection unit supplies a predetermined first electric potential to said contacting target conductor region in a state where said fuse is grounded so as to detect whether an electric potential at said contacting target conductor region is high or low, and detects that said contacting target conductor region and said fuse are not electrically connected in the case where said potential at said contacting target conductor region is high, and detects that said contacting target conductor region and said fuse are electrically connected in the case where said electric potential at said contacting target conductor region is low.

A method for determining a fuse state in a semiconductor device comprising a fuse which includes a conductive material and is formed on a semiconductor substrate and a contacting target conductor region which is placed around said fuse on said semiconductor substrate and formed so as to be electrically connected to said fuse through the conductive material constituting said fuse when a process for cutting said fuse is carried out, the method for determining said fuse state, comprising:

• detecting whether or not said fuse is electrically disconnected;
• detecting whether or not said contacting target conductor region and said fuse are electrically connected;
• and
• determining that said fuse is in a cut state when electrical disconnection of said fuse is detected or electrical connection between said contacting target conductor region and said fuse is detected,
• wherein in said detecting whether or not said contacting target conductor region and said fuse are electrically connected, a predetermined electric potential is supplied to said contacting target conductor region and it is detected whether an electric potential at the contacting target conductor region is high or low in a state where said fuse is grounded, and in the case where said electric potential is low at the contacting target conductor region, electrical connection between said contacting target conductor region and said fuse is detected, and in the case where said electric potential at the contacting target conductor region is high, electrical disconnection between said contacting target conductor region and said fuse is detected.