Week+of+April+12-16

Week of April 12-16

I went into the lab for a total of 4 and a half hours this week. I have now switched to scanning primarily octanethiol on Au (111) samples...however I have also scanned dibenzoal pentace when an octane thiol sample had not yet been prepared.

Due to the increase in temperature lately the scope has been driftier...however, offsetting some of the driftiness was the fact that I had descent tips some of the time. While I had been intending on posting my images...I have been confused lately as to the images that I have been getting or rather the processing that the program does on its own. When I scan I get an image and its features are clear when they are displayed on the screen, however when we look at these images in the data analysis software they seem to be very dark and you can't see well defined features. When I last uploaded my document with all of my scans these images appeared to be processed and they were just copied from data analysis software. The images I am getting now aren't appearing at all until you go through and process them using matlab, which is a long process. So in short...I am unable to upload images without processing them through matlab.

When I began scanning the on wednesday the tip would not approach the sample. I quickly fixed by changing the tip multiple times and moving the sample so that a different part would be scanned. I was able to scan and shoot the sample with the laser and achieve a large amount of expansion. Not 6000 angstroms, but close due to the fact that my alignment was partially off. I realligned and later tried scanning again. I pulled the tip back from the surface and then shot the laser at the sample to see how far the gold expanded. The single line scan, however, when we take a cross section does not show how far away from the sample the tip was when the scan was begun. I did however note the reading on the z-offset which correlates to a voltage and this correlates to the distance away from the sample...so I can calculate the total expansion. This tip had been pulled back to a reading of -72 from 0 and expanded to around zero when the sample was shot with the laser.

Also I am currently reading the paper Ambient-Pressure Vapor Deposition of Octanethiol Self-Assembled Monolayers.