Masatoshi Terayama

New development system for EUV mask

EUV lithography is one of the approaches to manufacture half-pitch 1x nm devices. It is required high CD mean control, high CD uniformity, and low defect density for EUV mask in common with DUV mask. In addition, backside defect density is drastically tightened to avoid overlay error in EUV scanner. PGSD (Proximity-Gap-Suction-Development), a novel development system we developed, has kept upgrading to satisfy the demand of most-advanced devices, and 3rd-generation PGSD (PGSD Gen. III) which developed for EUV mask will be contributed to achieve required accuracy of EUV mask. In this paper, we propose the concept of PGSD Gen. III and report its performance.

Study of electric-field-induced-development method

Mask development process for 2x nm node devices needs stringent CD uniformity and CD linearity. To evaluate and improve these CD qualities, we proposed to introduce electric-field-induced-development method into proximity gap suction development system (PGSD). It is the way to develop with applying electric potential to the metallic development nozzle to stimulate the movement of hydroxide ions. In this paper, we will report the effect of electric-field-induced-development method on CD uniformity and CD linearity.