New generation electron beam resists: a review

The semiconductor industry has already entered the sub-10 nm region, which has led to the development of cutting-edge fabrication tools. However, there are other factors that hinder the best outcome of these tools, such as the substrate and resist materials, pre- and postfabrication processes, etc. Among the lithography techniques, electron beam lithography (EBL) is the prime choice when a job requires dimensions lower than 10–20 nm, since it can easily achieve such critical dimensions in reasonable time and effort. When obtaining pattern features in single nanometer regime, the resist material properties play an important role in determining the size. With this agenda in mind, many resists have been developed over the years suitable for attaining required resolution in lesser EBL writing time. This review article addresses the recent advancements made in EBL resists technology. It first describes the different lithography processes briefly and then progresses on to the parameters affecting the EBL fabrications processes. EBL resists are then bifurcated into their “family types” depending on their chemical composition. Each family describes one or two examples of the new resists, and their chemical formulation, contrast-sensitivity values, and highest resolution are described. The review finally gives an account of various alternate next-generation lithography techniques, promising dimensions in the nanometer range

The history of nanoscience and nanotechnology: From chemical-physical applications to nanomedicine

Nanoscience breakthroughs in almost every field of science and nanotechnologies make life easier in this era. Nanoscience and nanotechnology represent an expanding research area, which involves structures, devices, and systems with novel properties and functions due to the arrangement of their atoms on the 1-100 nm scale. The field was subject to a growing public awareness and controversy in the early 2000s, and in turn, the beginnings of commercial applications of nanotechnology. Nanotechnologies contribute to almost every field of science, including physics, materials science, chemistry, biology, computer science, and engineering. Notably, in recent years nanotechnologies have been applied to human health with promising results, especially in the field of cancer treatment. To understand the nature of nanotechnology, it is helpful to review the timeline of discoveries that brought us to the current understanding of this science. This review illustrates the progress and main principles of nanoscience and nanotechnology and represents the pre-modern as well as modern timeline era of discoveries and milestones in these fields

CHEMICALLY AMPLIFIED RESISTS FOR ELECTRON BEAM LITHOGRAPHY

This thesis describes the development of chemically amplified resists for electron beam lithography. The techniques and concepts oflithography are discussed and the motivations for the development of chemically amplified resists are examined. The experimental techniques used in this work are then described. Two groups of resists, derivatives of fullerene and derivatives of triphenylene, were tested for chemical amplification and the results obtained from the research are presented. A systematic study of the response of several methanofullerenes and polysubstituted triphenylene derivatives before and after chemical amplification is presented. Films of the compounds were prepared by dissolving the resists in solvents such as chloroform and adding to the solution various concentrations of certain photoacid generators and crosslinkers, and spin coating the mixture on hydrogen terminated silicon wafers. The films were irradiated using 20 keY electrons. Post exposure bakes between 90 to 120 'C for 30 to 180 s were applied to the resists before development with non-polar solvents such as monochlorobenzene. Most of the chemically amplified resists showed sensitivity enhancement compared to their pure counterparts. Fullerene derivative, 3' H-cyclopropa [I, 9, 5, 6] fullerene-C60-Ih - 3', 3'- carboxylic [ 2-2-(2-hydroxyethoxy) ethoxyl ethyl] ester (a mixture of adducts) demonstrated the highest sensitivity enhancement with the incorporation of an epoxy novolac crosslinker and bis[4-di(phenylsulfonio) phenyl]sulfide bis(hexafluorophoshate) as photoacid generator with a sensitivity of -8 ~Clem' and a resolution of -24 nm. The polysubstituted triphenylene derivative, 2,6,10-trihydroxy-3,7,11- tri(pentyloxy) triphenylene, showed a sensitivity of -5 ~Clem' when the crosslinker hexamethoxymethylmelamine and the photoacid generator triphenylsulfonium triflate were added to the compound. However, fine patterning in the resist was not very successful due to acid diffusion. An alternative triphenylene derivative similar to 2,6, 1 0-trihydroxy-3,7, 11- tri(pentyloxy) triphenylene, with epoxides incorporated into the structure showed better results with the photoinitiator bis[ 4-di(pheny lsulfonio) phenyl]sulfide bis(hexa fluorophoshate). The chemically amplified C51epoxide demonstrated a sensitivity of ~9 f..!C/cm2 and a resolution of 40 nm. The etch durabilities of these chemically amplified resists for dry plasma etching with SF6 are reasonably high, comparable to a conventional high durability novolac resist

Contributions of DOE Weapons Labs and NIST to Semiconductor Technology

This report examines how NIST and DOE weapons laboratories could contribute to advances in semiconductor technology aimed specifically at civilian applications. Semiconductor technology was chosen as an example of a technology focus for a civilian technology initiative, primarily because the industry had already developed a set of comprehensive technology roadmaps and the federal labs had substantial expertise in the area

Assessing the Success of Dual Use Programs: The Case of DARPA\u27s Relationship with SEMATECH—Quiet Contributions to Success, Silenced Partner, or Both

This dissertation investigates a major change in U.S. Government research and development policy away from its traditional mission-based model, toward a distinctly commercially-oriented research approach. The SEMATECH project is offered as an example of a Government Industry Partnership (GIP) dedicated to the development of dual-use programs (DUP) with the stated purpose of regaining technological superiority and market dominance in the production of a technology that had significant implications to national economic and military security. The study, builds upon the previous research of Horrigan, 1996; Porter, 1990; Geisler, 1993, 1997, 2003; Fong, 2000; Harlen 2008, 2010; and Brown, 2010. The study utilizes the process tracing methodology, and structured interviews to make some level of commentary concerning the effectiveness of the SEMATECH model and whether or not this model enabled the government and its primary sponsor, the Defense Advanced Research Projects Agency (DARPA) to acquire any tangible technological benefits (equities) for the funds invested. This study also endeavors to ascertain under what conditions DARPA contributed to the success of this project, and if the government served a distinct and necessary purpose in advancing competitiveness. The study presents unexpected findings concerning the government equities that should have emerged from SEMATECH. The unexpected findings reveal that the government did not receive any tangible return on its investment in SEMATECH in part because it did, or could not focus its efforts on repeatedly emphasized government research agendas. This inability to advance its research interest is a direct result of how SEMATECH was formed, and how it was funded. In spite of the severe limitations associated with the U.S. government\u27s abdication of direction setting prerogatives, DARPA still managed to make contributions that were necessary to the success of SEMATECH\u27s commercial and competitive objectives. Conclusions include indications that policy structured using SEMATECH as a model may not be the best model upon which to build future GIPs which focus on DUPs