The experimental study on relationship between shape of diamond and micro scratches

Chemical Mechanical Polishing (CMP) is very important process in integrated circuit fabrication. The most advantage of CMP is the scalability and it will shrink the pattern size of all kinds of IC devices. As the design rule shrinks in Semiconductor Devices, the need of reducing micro scratch level in the CMP Process is unavoidable. In the process of mechanical polishing, micro scratch is one of several side effects. Since the number of CMP Process steps have been increased in IC devices, the needs of reducing micro scratch in polishing processes is getting higher. There are many kinds of reasons to generate micro scratches in the CMP Process. While a pad is worn away by diamond disk, pad debris is generated incidentally. The pad debris is critical source to make micro scratches. It is discovered as various sizes according to diamond disk. Experiments were composed of samples of several grade of diamond on disk. We found out that the shape of diamond on disk affect to the size of pad debris. It was also closely related to the cause to occur micro scratch in CMP process closely. In this work, we are going to introduce some characteristics of some grades of diamonds and the results of our fabrication test.