Novel Approaches to Control Surface Reactions in Plasma Etching of Electronic Materials

dc.contributor.advisorOehrlein, Gottlieb Sen_US
dc.contributor.authorLi, Chenen_US
dc.contributor.publisherDigital Repository at the University of Marylanden_US
dc.contributor.publisherUniversity of Maryland (College Park, Md.)en_US
dc.description.abstractAdvanced semiconductor manufacturing requires precise plasma etching control for patterning complex semiconductor device structures. Pattern transfer into dielectric materials is one of the most frequently performed operation and traditionally done using continuous wave (CW) plasma etching processes based on fluorocarbon (FC) chemistries. Such etching methods are facing challenges when the critical dimension (CD) approach 10 nm. Issues include low materials etching selectivity, surface damage, roughness, and poor etching profile control. In this work, various aspects of low temperature plasma-based etching approaches are tailored for optimal plasma etching performance, including novel gaseous precursors for better control of gas phase and surface processes, tailoring the relative importance of radicals and ion bombardment at surface by sequential processes, and a new way to input energy to surfaces to stimulate etching reactions. We systematically studied the impact of molecular structure parameters of hydrofluorocarbon (HFC) precursors on plasma deposition of fluorocarbon (FC) and material etching performance. The HFC chemical composition and molecular structure such as ring structure, C=C, C≡C, C-O, C-H and degree of unsaturation have dramatic impacts on FC surface polymerization and material etching performance. Further, we report a new atomic layer etching (ALE) technique which temporally separates chemical reactant supply to a surface from ion bombardment induced etching. By this ALE method, the ion bombardment energy can be reduced to ensure low substrate damage and extremely high etching selectivity of two materials. Finally, we developed a hollow cathode electron beam etching system to reduce the energy and momentum input on the material surface by utilizing an electron-radical synergy effect. This present work has unveiled highly promising elements of a new roadmap of next generation semiconductor etching approaches and is expected to impact multiple areas of nanoscience and technology, including plasma etching of post-silicon materials. The use of specially selected gaseous precursor chemistry, temporal separation of radical exposure and energy-induced etching, and finally using electron bombardment for activation of surface etching, challenge our current understanding of semiconductor plasma processing and presents an important step forward in terms of the further industrial development of these approaches.en_US
dc.subject.pqcontrolledPlasma physicsen_US
dc.subject.pqcontrolledMaterials Scienceen_US
dc.subject.pquncontrolledAtomic Layer Etchingen_US
dc.subject.pquncontrolledthin filmen_US
dc.subject.pquncontrolledElectron beam plasmaen_US
dc.subject.pquncontrolledLangmuir probeen_US
dc.subject.pquncontrolledplasma etchingen_US
dc.subject.pquncontrolleddry etchen_US
dc.subject.pquncontrolledreactive ion etchen_US
dc.subject.pquncontrolledremote plasmaen_US
dc.subject.pquncontrolledsilicon oxideen_US
dc.subject.pquncontrolledSilicon nitrideen_US
dc.titleNovel Approaches to Control Surface Reactions in Plasma Etching of Electronic Materialsen_US


Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
2.46 MB
Adobe Portable Document Format