Masaya Fujisue

Advanced Alkali Cleaning Solution for Simplification of Semiconductor Cleaning Process

NH 4 OH/H 2 O 2 /H 2 O (called APM or SC–1) cleaning combined with megasonic irradiation is found to feature outstanding removal efficiency for various types of particulate contaminant. The conventional APM cleaning, however, allows metallic impurity in solution to adhere onto substrate surface, and it must be followed by acid cleaning such as HCI/IH 2 O 2 /H 2 O (called HPM or SC–2) cleaning to remove metallic impurity from substrate. The advanced APM cleaning using MC–1 which is alkali cleaning agent containing chelating agent has been developed, and this new cleaning is found capable for preventing various metallic impurities including Al in solution from contaminating substrate surface. Besides, with cleaning conditions optimized, the advanced APM cleaning using MC–1 can also remove metallic impurity from substrate surface. In short, this modified APM cleaning is capable for removing particle and metallic impurity at the same time, which is not possible with the conventional cleaning technology. The cleaning process of semiconductor manufacturing process can be simplified if HPM cleaning is eliminated by introducing the advanced APM cleaning using MC–1. This leads to drastic reduction of cleaning cost and improvement of throughput of the cleaning process.