报告题目：Block Copolymer Healing of Nano-scale Defects in Lithographic Patterns

报告人：Prof. Andrew K. Whittaker

Australian Institute for Bioengineering and Nanotechnology, Centre for Advanced Imaging,              The University of Queensland, Australia.

报告时间: 2015年9月23日上午9：00（星期三）

报告地点: 无机-超分子楼二楼圆形报告厅

报告摘要:

         Extreme ultraviolet lithography (EUVL) is arguably the leading candidate to replace 193 nm immersion double pattering for the high volume manufacture of semiconductor devices at the 32 nm node and below. This platform is attractive due to the use of a short wavelength (λ = 13.4 nm) photon source, which allows for single patterning steps and mask layouts. However, in addition to challenges with EUV source power, a critical issue preventing implementation of this technology is line edge roughness (LER), which arises predominantly from shot noise and diffusion of photoacid in chemically-amplified resists. As these processes are stochastic and inherently not able to be compensated for, the industry has resolved to apply post-exposure processing steps to help remediate the roughness so generated.

In this presentation I will initially describe the state of the art in photolithography, then the development of several promising approaches, based on control of deposition of block copolymers, to “repairing” line edge roughness.1-6 In the first approach, we exploit the directed self-assembly of lamellar-forming polystyrene-b-poly(D-lactide) block copolymers that when deposited and annealed below the glass temperature of the resist can form a single sacrificial domain capable of being selectively removed by an etching process (in our case reactive ion etching). The self-assembled domain creates smoother surfaces with respect to the resist sidewall and hence can be used to reduce the LER of patterned resist features. In the second approach we deposit partially-charged diblock copolymers of dimethylaminoethyl methacrylate and t-butyl methacrylate in the form of vesicles into the pattern and exploit electrostatic interactions to achieve a significant reduction in roughness. The presentation will present the theory and application of block copolymer self-assembly to lithography.