December+6-7

December 6th:

Today I annealed a piece of Au(III) and proceeded to scan it. The plan was to scan the sample, and then give it to Becky so she could expose it to the Polonium-210 overnight. I am still using the portable AFM, and it still has problems getting a perfectly clear image. Towards the end of the day, Becky suggested adjusting the amount of weight on the vibration isolation table and finely adjusting it. The images are coming out well, except for the parallel lines and occasional spike.



December 7th:

On Dr. Loughran's suggestion, I turned the microscope on, still the portable AFM, and let it sit for a little while. It was about 30 minutes. I did not change the tip, but the images were some of the best in weeks. The sample is the same from yesterday, Becky took it after I finished yesterday and exposed it on the Polonium-210 with half of it covered. We thought of possible reasons for the interference, which is not present anymore. It may have been the wrong calibration on the vibration isolation table, which I adjusted. It may have been outside interference we can't control. I hope that whatever the source was, it has either been fixed or just left. There was one odd event with some of the scans, specifically the last three. For some reason, the line scan, showing the horizontal topography of the surface, was not smooth, it was stepped. It started for no apparent reason; i tried adjusting the gains and possible nearby interferences, but to no avail. However, this disturbance does not disturb the scan very much, as it is still accurate. Finally, the scans twice dropped off for no apparent reason- there may have been a large crater or an edge, but it was only on a couple images. This has happened before, and the standard procedure is to just move the scan area.



These are the images with the strange line graph. If the problem had shown up earlier, then I would have had more time to fix it.