Study on Defect Reduction and Yield Improvement of MIM Al Deposition Process

MIM is the three words of metal insulator metal. This structure is always designed into IC device and act as a big capacitor to keep the stable working voltage. In MIM loop, the upper capacitor board is made of thin Al film. Because of this character, the defect on upper capacitor board is difficult to control and even lead yield loss. In this paper, defect of MIM Al layer is introduced and the mechanism is studied. Through DOE test, MIM defect such as arcing and tiny defect can be reduced to a low level and yield can be improved.