There was a 10% test which was 30 minutes long. One question was explaining the different models for an electric double layer and the other was explaining possible synthesis methods for 2 different structures. Note that a combination of methods can be used so do gain a good understanding of the process flow of each method. On alternate weeks, there will be a 1 hour lab session for us to synthesise some nanoparticles. This is for the 20% pairwork project, where we had to characterise the nanoparticles using SEM and XRD as well as identify the synthesis method used.
The second half taught by A/P van Kan focused on a top-down approach of nanosynthesis, with a large part emphasising on different beams (photons, electrons, ions) and their interactions with different types of photoresists. Rutherford backscattering is introduced as well as its spectra. Finally, fringe topics such as 3d printing, nanoimprinting (hot embossing, step and flash lithography) and etching conclude
the course. Tutorials were basically simulation labs which were done in the class itself (no traditional pen and paper questions basically) and had to be used for the simulation assignments
There was a 15% test which was 50 minutes long. The questions involved drawing the resist profile after exposure under a mask with a certain dose, fabricating a certain structure, some factual questions regarding ion beams and describing different lithography methods to fabricate greyscale microlenses. A good understanding of the advantages and disadvantages of each lithography technique was needed to identify what could or could not be done in practice. The other two simulation assignments were 7.5% each and took up a huge amount of time. The first assignment involved fabricating structures and characterising them using electron and proton beams. SRIM and CASINO were the software used for this. The second assignment involved fitting an RBS spectrum and hence deducing the thickness, stoichiometry and other parameters. Be prepared to spend a huge amount of time if you want to get a near perfect fit for the spectrum because of the sheer number of variables to be tuned. For me I did not bother much about the fit because I didn’t have the time.
The 40% finals took most of us by shock, mainly because of the extremely “trivia” based questions in the second half such as which plane in silicon etches fastest and to draw an RBS detector system. This was radically different from past year papers which had more “unseen” questions like identifying the RBS spectrum when the ion beam was not aligned to the substrate at normal incidence.
A different kind of difficulty emphasising more on the details I would say. The questions from the first half were still alright and similar to those in past year papers.
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