Scanning thermal lithography for nanopatterning of polymers. Transient heat transport and thermal chemical functionalization across the length scales
Promotion date: 11. February 2011
Promotor: Prof. dr. G.J. Julius Vancso
Assistant Promotor: Dr. Holger Schönherr
An alternative nanotechnology tool for scanning probe lithography is developed: scanning thermal lithography (SThL). Heated atomic force microscopy (AFM) cantilevers are used as spatially controlled, highly localized, heat sources for the thermochemical surface functionalization of tert-butyl (meth)acrylate based polymer film platforms.
The surface exposed esters are known to be thermally cleavable at temperatures varying from 150 to 280 degree Celsius.
The highest achieved resolution obtained with SThL was approximately 20 nm, which is below the radius of curvature of the used probes.
Was there a special moment during the thesis project that was of decisive importance?
There were some stages I went through, so to say. In the beginning of the project, I studied the heat flow from heated cantilevers to a polymer substrate. The experiments using the heated cantilever in contact with the polymer film, were relatively simple to conduct. Nevertheless, they turned out to be of significant importance.
After this I studied various polymer films, and discovered the reaction mechanisms did vary unexpectedly, at different time scales. We reached the critical length scale of about one hundred nanometers and below, after thorough reconsideration of the used polymer platforms.
What kind of researcher are you?
I am an experimentalist, without a doubt. I like to spend hours and hours in the lab, experimenting in the fume hood or with the AFM. Trying all kinds of new things, I achieve a good feeling and understanding of the matter underhand, in a limited amount of time. From the data points found, I can skip to theoretical translation quite easily.
In the last part of the thesis project, however, I learned that in depth reflection can lead to unthought-of experimental results as well.
Did your work lead to some nice publications?
In the first year, I published my findings in Langmuir. After this ACS Nano and Advanced Functional Materials followed. Now, four more publications are still on their way.
What are your future plans?
Right now, I am working with an innovative start-up company, Aerotech Development BV, in Heteren. Within the university, we are looking for new processes to develop high performance thermal isolation materials. Three master students are working on aspects of this research. The aim is to start a spin-off company, based on this research.
I am challenged by the entrepreneur part of this job. When the company starts to grow, I grow along with it. I hope to contribute in a decisive way and perhaps make a future job out of it.
What, in your opinion, is important for Mesa+ to stay successful in the future?
The facilities and expert networks are there. When working within Mesa+, one can have all the knowledge and expertise needed, because of the open atmosphere existing there. Mesa+ is a multidisciplinary and multicultural organisation.
I feel some apparatus equipment can be shared more efficiently, by sharing more knowledge between different groups, simply by knowing exactly what is available (including the experience) on the different floors.