CMP pressure distribution measurement

02/01/1999

CMP pressure distribution measurement

The I-Scan system uses a paper-thin (<0.08 mm), flexible, grid-based sensor that is composed of conductive and semi-conductive inks. The intersecting points of the grid`s conductive rows and columns form the sensing locations, and by separating the rows and columns with a material that varies its electrical resistance with applied force, each intersection of the sensor becomes a force sensor. The computerized system electronically scans and measures the change in resistance at each sensing cell to determine the timing, force, and location of contacts on its surface. Windows-based I-Scan software allows the user to view the information statically or dynamically in 2-D or 3-D graphically informative displays. Some applications of I-Scan are: taking pressure distribution measurements across the face of the wafer; performing polishing head alignment; measuring and detecting polishing pad wear; performing back pressure balancing; and acting as a quality-control tool for checking rebuilt carriers. Tekscan Inc., South Boston, MA; ph 617/464-4500, fax 617/464-4266, e-mail [email protected].