Introduction to Microlithography: Chemistry, Materials and Processing

Level: Introductory Length: 4 hours Format: Online Intended Audience: Process engineers, technicians, scientists, and managers new to the field of microlithography, and those who want to understand the physical and chemical principles that are the basis for resist function. Description: This course provides an overview of the chemistry that is responsible for generation of differential solubility in resists and the effects of processing variables on the final relief image. While optical exposure is the major focus of this course, electron beam and x-ray exposure are also addressed. The course provides an overview description of the chemical basis for various resist designs, ranging from the older DNQ/novolak resists to chemically amplified resists for 248nm, 194 nm dry and immersion, and EUV. It provides a discussion of methods for pitch multiplication such as Multiple Patterning, Self Aligned Patterning, DSA, etc. The course also includes a discussion of the influence of material and process variables on the tradeoffs between resolution, line edge roughness and throughput. Learning Outcomes: This course will enable you to: paraphrase Moore’s Law explain the role of photolithography in enabling Moore’s Law explain why mass production requires mask-using, not serial processes describe Rayleigh’s criteria and why they show that continued shrink requires moving to shorter wavelength explain cyclized rubber resists and why they were placed by DNQ/novolaks describe the chemistry of DNQ materials and their interaction with novolak resins summarize how modifying molecular weight distribution of novolaks improves resist performance discuss the chemical amplification concept for photoresists summarize the need for transparent resins drives the design of polymers for the different wavelengths discuss the tools for immersion lithography and how they drive materials needs describe double patterning explain limitations of EUV lithography arising from low photon numbers and high photon energy discuss the different kinds of EUV photoresists describe EUV resist performance metrics and the RLS figure of merit describe the concepts behind Directed Self Assembly (DSA) interpret DSA’s Strengths and imitations explain how EUV and DSA can be complementary technologies explain that continued shrink is approaching physical and economic limits summarize how moving to 3D structures will continue to allow transistor density increases interpret what this will mean for different device types explain that with EUV, the race for the next wavelength has ended explain that Moore’s Law is changing but will continue in a new form (Moore’s Law 2.0) Instructor(s): Ralph R. Dammel has been actively involved in x-ray, e-beam, 157 nm, 193 nm, DUV, i- and g-line resist research since 1986. Beyond photoresists, his research interests include anti-reflective coatings and other performance enhancing materials, Directed Self Assembly, novel carbon materials, and other performance materials. He is currently employed as Technology Fellow for the Performance Materials Division of Merck KGaA, Darmstadt, and is based in Philadelphia, PA. SPIE online courses are on-demand and self-paced, with access for one year. For more information visit: spie.org/education/online-courses