STI 28nm pitch guided DSA to enable the 450mm tools qualification and transition

One of the options to reduce the cost related to the next generation of devices in the semiconductor industry is the scale up of the wafer size from 300mm to 450mm. The 450mm transition requires the development and qualification of new tools and processes. G450C, a partnership between five international integrated circuit (IC) makers and CNSE (College of Nanoscale Science and Engineering), has been created to lead this transition. Patterned wafers are necessary to test and demonstrate these 450mm tools. The challenge has been to develop and validate a patterning process — capable of producing advanced-node-relevant features — in a timely manner to enable the process and tool demonstrations. Based on the provided and available 450mm processes and tools, a 28nm pitch STI (Shallow Trench Isolation) structure on a 450mm wafer was developed. This feature was made possible using a 193nm immersion lithography DSA (Directed Self Assembly) technique. This paper will update G450C program status and show process results obtained on 450mm wafers using an STI structure.