Overcoming mask etch challenges for 45 nm and beyond

Increasingly complex RET techniques need to be used in the sub wavelength regime which will drive up the mask costs, as well as the design costs. Some of the RET techniques used involves the use of OPC, PSM and hard mask. In order to reduce the costs it is desirable to have uniform performance on shuttle masks, which can help to reduce manufacturing costs. The micro loading and macro loading are of concern to mask makers because of the varying loads being etched within the mask. It is critical to have a mask etcher that provides excellent CD uniformity, CD bias, CD linearity and etch profile in order to have image fidelity of the OPC structures as well as sustainable yields. This paper discusses micro and macro loading challenges on BIM and APSM masks and the advantages of using the Applied Materials' next generation mask etcher.