Structure and method for determining a defect in integrated circuit manufacturing process
The present invention discloses a structure and a method for determining a defect in integrated circuit manufacturing process. Test keys are designed for the structure to be the interlaced arrays of grounded and floating conductive cylinders, and the microscopic image can be predicted to be an interlaced pattern of bright voltage contrast (BVC) and dark voltage contrast (DVC) signals for a charged particle beam imaging system. The system can detect the defects by comparing patterns of the detected VC signals and the predicted VC signals.
1. A test structure for determining a defect of a semiconductor device, comprising:
a plurality first cylindrical conductors, each of said first cylindrical conductors being grounded wherein said first cylindrical conductor is grounded through at least one first conductive plug and an active area wherein said first conductive plug and said active area are under said first cylindrical conductor; and
a plurality of second cylindrical conductors, each of said second cylindrical conductors being floated, said first and second cylindrical conductors being interlaced and vertical to a upper surface of said test structure wherein said second cylindrical conductor is floated through at least one second conductive plug and an isolation member,
wherein said defect is determined by monitoring the voltage contrast from a charged particle microscope image of said first and second cylindrical conductors.
2. The test structure for determining a defect of a semiconductor device of claim 1 , wherein said defect comprises a piping defect between said first and second conductive plugs.
3. The test structure for determining a defect of a semiconductor device of claim 1 , wherein said defect comprises an electrical short between said first and second cylindrical conductors.
4. The test structure for determining a defect of a semiconductor device of claim 1 , wherein said defect is determined by monitoring a bright voltage contrast of said first and second cylindrical conductors.