LabAdviser/Technology Research/Nanoscale characterization of ultra-thin metal films for nanofabrication applications: Difference between revisions
No edit summary |
|||
| Line 19: | Line 19: | ||
The project involved the introduction of the recently developed transmission Kikuchi diffraction (TKD) technique for the characterization of the crystal structure, grain size, and crystallographic texture of polycrystalline thin films. The remarkable potential of TKD for the in-situ analysis of thin films at elevated temperatures was revealed through the in-situ investigation of solid-state dewetting of Au, enabling to observe the start of the dewetting at a temperature as low as 150°C and demonstrating the crucial role of temperature in the modification of the nanostructure of metal thin films during nanofabrication. The data acquired during solid state dewetting were used to qualitatively study the formation and expansion of the holes in the film. A new criterion for the detection of the temperature of formation of the holes in the film was introduced and an in-situ monitoring of the formation and expansion of the holes in the Au film was also performed. This allowed to observe the formation of the holes exclusively in the positions of high surface energy grains and the reduction of the interface energy of the system by the elimination of grain boundaries and by grain coalescence. | The project involved the introduction of the recently developed transmission Kikuchi diffraction (TKD) technique for the characterization of the crystal structure, grain size, and crystallographic texture of polycrystalline thin films. The remarkable potential of TKD for the in-situ analysis of thin films at elevated temperatures was revealed through the in-situ investigation of solid-state dewetting of Au, enabling to observe the start of the dewetting at a temperature as low as 150°C and demonstrating the crucial role of temperature in the modification of the nanostructure of metal thin films during nanofabrication. The data acquired during solid state dewetting were used to qualitatively study the formation and expansion of the holes in the film. A new criterion for the detection of the temperature of formation of the holes in the film was introduced and an in-situ monitoring of the formation and expansion of the holes in the Au film was also performed. This allowed to observe the formation of the holes exclusively in the positions of high surface energy grains and the reduction of the interface energy of the system by the elimination of grain boundaries and by grain coalescence. | ||
The influence that Ti and Cr adhesion layers have on the microscopic and macroscopic properties of Au ultra-thin metal films was investigated at room temperature, with the analysis carried out on both bilayer and multilayer systems in order to obtain a more complete view of the interaction. The obtained results led to the formulation of a revised adhesion model for the Ti/Au and Cr/Au bilayer systems, which gives a description of the adhesion layer-overlayer interaction and can be used by the research community as guide-lines for adhesion layer and thin-film stack engineering. The model was also accompanied by the formulation of recommendations about the use of adhesion layers for different nanofabrication applications. The analysis of Ti/Au/Ti and Cr/Au/Cr multilayer systems allowed to obtain experimental evidence of the type of chemical bonding that leads to the increase of adhesion. | The influence that Ti and Cr adhesion layers have on the microscopic and macroscopic properties of Au ultra-thin metal films was investigated at room temperature, with the analysis carried out on both bilayer and multilayer systems in order to obtain a more complete view of the interaction. The obtained results led to the formulation of a revised adhesion model for the Ti/Au and Cr/Au bilayer systems, which gives a description of the adhesion layer-overlayer interaction and can be used by the research community as guide-lines for adhesion layer and thin-film stack engineering. The model was also accompanied by the formulation of recommendations about the use of adhesion layers for different nanofabrication applications. The analysis of Ti/Au/Ti and Cr/Au/Cr multilayer systems allowed to obtain experimental evidence of the type of chemical bonding that leads to the increase of adhesion. A positive impact of the adhesion layers on the stability of the Au nanostructure at high temperatures was observed with TKD, with Ti and Cr preserving the continuity of the Au layer up to a temperature of 500°C without the observation of dewetting. | ||
A positive impact of the adhesion layers on the stability of the Au nanostructure at high temperatures was observed with TKD, with Ti and Cr preserving the continuity of the Au layer up to a temperature of 500°C without the observation of dewetting. | |||
==Dissemination== | ==Dissemination== | ||