# Chateau de la Tobler

## Thursday, May 01, 2008

### Research details

This is for those interested in the finer details of the elements I use and why. Anyone not interested should avoid this post at it will most likely bore you.
I need 2 different metallic films in order to complete the circuit I need to test my nanowires. The first metallic film needs to be added before the sample can go into my ultra-high vacuum chamber. This film needed to make contact with the sample holder and be partially exposed to the area when the second film will be added later. This first film also needs to stay metallic before, during, and after heat cleaning of the sample. The sample will be cleaned at 1200 Celsius.
The second metallic film needed will be added directly to the nanowires. This is the film that I needed to get a nice sharp edge so that I could find nanowires partially covered and partially exposed. I have had success in this area recently.
At first I used gold for the second film. This was because the yellow color would make it easier to find the edge since the background is silvery. We found out that platinum was smoother, atomically speaking, then gold. This meant that the clumps that made up the film were smaller and thus could be packed closer together. As an example, think of making a flat layer of grape fruits as compared to a flat layer of grapes. The grapes will be a lot smoother then the grape fruits.
We thought that we could use platinum for the first film as well. It turns out that platinum does not stay metallic after being exposed to 1200 degrees C. That is why we are trying to use Ta or Mo. I am currently trying to figure out if these films will survive the 1200 degree C temperatures.
Hope this was not as boring as it could be. This would a lot more sense if I could have uploaded the diagram I made. For some reason it is always taking too long and thus it gives up before the picture can be loaded. It's only 26kB. Oh well. Love you all.

<< Home